Exemplo n.º 1
0
def rare_standalone(
    init_gpa=False,  # Starts the gpa
    nScans=1,  # NEX
    larmorFreq=3.08,  # MHz, Larmor frequency
    rfExAmp=0.3,  # a.u., rf excitation pulse amplitude
    rfReAmp=0.3,  # a.u., rf refocusing pulse amplitude
    rfExTime=35,  # us, rf excitation pulse time
    rfReTime=70,  # us, rf refocusing pulse time
    echoSpacing=10,  # ms, time between echoes
    preExTime=0.,  # ms, Time from preexcitation pulse to inversion pulse
    inversionTime=0.,  # ms, Inversion recovery time
    repetitionTime=200.,  # ms, TR
    fov=np.array([140., 150., 180.]),  # mm, FOV along readout, phase and slice
    dfov=np.array([0., 0., 0.]),  # mm, displacement of fov center
    nPoints=np.array([140, 80,
                      10]),  # Number of points along readout, phase and slice
    etl=10,  # Echo train length
    acqTime=4,  # ms, acquisition time
    axes=np.array([2, 1, 0]),  # 0->x, 1->y and 2->z defined as [rd,ph,sl]
    axesEnable=np.array([1, 1, 1]),  # 1-> Enable, 0-> Disable
    sweepMode=1,  # 0->k2k (T2),  1->02k (T1),  2->k20 (T2), 3->Niquist modulated (T2)
    rdGradTime=5,  # ms, readout gradient time
    rdDephTime=2,  # ms, readout dephasing time
    phGradTime=1,  # ms, phase and slice dephasing time
    rdPreemphasis=1.00,  # readout dephasing gradient is multiplied by this factor
    drfPhase=0,  # degrees, phase of the excitation pulse
    dummyPulses=1,  # number of dummy pulses for T1 stabilization
    shimming=np.array([-70, -90.,
                       10]),  # a.u.*1e4, shimming along the X,Y and Z axes
    parFourierFraction=1.0  # fraction of acquired k-space along phase direction
):

    freqCal = 1

    # rawData fields
    rawData = {}

    # Conversion of variables to non-multiplied units
    larmorFreq = larmorFreq * 1e6
    rfExTime = rfExTime * 1e-6
    rfReTime = rfReTime * 1e-6
    fov = np.array(fov) * 1e-3
    dfov = np.array(dfov) * 1e-3
    echoSpacing = echoSpacing * 1e-3
    acqTime = acqTime * 1e-3
    shimming = shimming * 1e-4
    repetitionTime = repetitionTime * 1e-3
    preExTime = preExTime * 1e-3
    inversionTime = inversionTime * 1e-3
    rdGradTime = rdGradTime * 1e-3
    rdDephTime = rdDephTime * 1e-3
    phGradTime = phGradTime * 1e-3

    # Inputs for rawData
    rawData['seqName'] = 'RareBatches_Standalone'
    rawData['nScans'] = nScans
    rawData['larmorFreq'] = larmorFreq  # Larmor frequency
    rawData['rfExAmp'] = rfExAmp  # rf excitation pulse amplitude
    rawData['rfReAmp'] = rfReAmp  # rf refocusing pulse amplitude
    rawData['rfExTime'] = rfExTime  # rf excitation pulse time
    rawData['rfReTime'] = rfReTime  # rf refocusing pulse time
    rawData['echoSpacing'] = echoSpacing  # time between echoes
    rawData['preExTime'] = preExTime
    rawData['inversionTime'] = inversionTime  # Inversion recovery time
    rawData['repetitionTime'] = repetitionTime  # TR
    rawData['fov'] = fov  # FOV along readout, phase and slice
    rawData['dfov'] = dfov  # Displacement of fov center
    rawData[
        'nPoints'] = nPoints  # Number of points along readout, phase and slice
    rawData['etl'] = etl  # Echo train length
    rawData['acqTime'] = acqTime  # Acquisition time
    rawData[
        'axesOrientation'] = axes  # 0->x, 1->y and 2->z defined as [rd,ph,sl]
    rawData['axesEnable'] = axesEnable  # 1-> Enable, 0-> Disable
    rawData[
        'sweepMode'] = sweepMode  # 0->k2k (T2),  1->02k (T1),  2->k20 (T2), 3->Niquist modulated (T2)
    rawData['rdPreemphasis'] = rdPreemphasis
    rawData['drfPhase'] = drfPhase
    rawData['dummyPulses'] = dummyPulses  # Dummy pulses for T1 stabilization
    rawData['parFourierFraction'] = parFourierFraction
    rawData['rdDephTime'] = rdDephTime
    rawData['shimming'] = shimming

    # Miscellaneous
    larmorFreq = larmorFreq * 1e-6
    gradRiseTime = 400e-6  # Estimated gradient rise time
    gSteps = int(gradRiseTime * 1e6 / 5) * 0 + 1
    addRdPoints = 10  # Initial rd points to avoid artifact at the begining of rd
    randFactor = 0e-3  # Random amplitude to add to the phase gradients
    if rfReAmp == 0:
        rfReAmp = rfExAmp
    if rfReTime == 0:
        rfReTime = 2 * rfExTime
    resolution = fov / nPoints
    rawData['resolution'] = resolution
    rawData['gradRiseTime'] = gradRiseTime
    rawData['randFactor'] = randFactor
    rawData['addRdPoints'] = addRdPoints

    # Matrix size
    nRD = nPoints[0] + 2 * addRdPoints
    nPH = nPoints[1] * axesEnable[1] + (1 - axesEnable[1])
    nSL = nPoints[2] * axesEnable[2] + (1 - axesEnable[2])

    # ETL if nPH = 1
    if etl > nPH:
        etl = nPH

    # parAcqLines in case parAcqLines = 0
    parAcqLines = int(int(nPoints[2] * parFourierFraction) - nPoints[2] / 2)
    rawData['partialAcquisition'] = parAcqLines

    # BW
    BW = nPoints[0] / acqTime * 1e-6
    BWov = BW * hw.oversamplingFactor
    samplingPeriod = 1 / BWov
    rawData['bw'] = BW
    rawData['samplingPeriod'] = samplingPeriod

    # Readout gradient time
    if rdGradTime > 0 and rdGradTime < acqTime:
        rdGradTime = acqTime
    rawData['rdGradTime'] = rdGradTime

    # Phase and slice de- and re-phasing time
    if phGradTime == 0 or phGradTime > echoSpacing / 2 - rfExTime / 2 - rfReTime / 2 - 2 * gradRiseTime:
        phGradTime = echoSpacing / 2 - rfExTime / 2 - rfReTime / 2 - 2 * gradRiseTime
    rawData['phGradTime'] = phGradTime

    # Max gradient amplitude
    rdGradAmplitude = nPoints[0] / (hw.gammaB * fov[0] *
                                    acqTime) * axesEnable[0]
    phGradAmplitude = nPH / (2 * hw.gammaB * fov[1] *
                             (phGradTime + gradRiseTime)) * axesEnable[1]
    slGradAmplitude = nSL / (2 * hw.gammaB * fov[2] *
                             (phGradTime + gradRiseTime)) * axesEnable[2]
    rawData['rdGradAmplitude'] = rdGradAmplitude
    rawData['phGradAmplitude'] = phGradAmplitude
    rawData['slGradAmplitude'] = slGradAmplitude

    # Readout dephasing amplitude
    rdDephAmplitude = 0.5 * rdGradAmplitude * (gradRiseTime + rdGradTime) / (
        gradRiseTime + rdDephTime)
    rawData['rdDephAmplitude'] = rdDephAmplitude

    # Phase and slice gradient vector
    phGradients = np.linspace(-phGradAmplitude,
                              phGradAmplitude,
                              num=nPH,
                              endpoint=False)
    slGradients = np.linspace(-slGradAmplitude,
                              slGradAmplitude,
                              num=nSL,
                              endpoint=False)

    # Now fix the number of slices to partailly acquired k-space
    nSL = (int(nPoints[2] / 2) + parAcqLines) * axesEnable[2] + (1 -
                                                                 axesEnable[2])

    # Add random displacemnt to phase encoding lines
    for ii in range(nPH):
        if ii < np.ceil(nPH / 2 - nPH / 20) or ii > np.ceil(nPH / 2 +
                                                            nPH / 20):
            phGradients[ii] = phGradients[ii] + randFactor * np.random.randn()
    kPH = hw.gammaB * phGradients * (gradRiseTime + phGradTime)
    rawData['phGradients'] = phGradients
    rawData['slGradients'] = slGradients

    # Set phase vector to given sweep mode
    ind = mri.getIndex(etl, nPH, sweepMode)
    rawData['sweepOrder'] = ind
    phGradients = phGradients[ind]

    def createSequence():
        phIndex = 0
        nRepetitions = int(nPH / etl + dummyPulses)
        scanTime = 20e3 + nRepetitions * repetitionTime
        rawData['batchTime'] = scanTime * 1e-6
        if rdGradTime == 0:  # Check if readout gradient is dc or pulsed
            dc = True
        else:
            dc = False
        # Set shimming
        mri.iniSequence(expt, 20, shimming)
        for repeIndex in range(nRepetitions):
            # Initialize time
            tEx = 20e3 + repetitionTime * repeIndex + inversionTime + preExTime

            # First I do a noise measurement.
            if repeIndex == 0:
                t0 = tEx - preExTime - inversionTime - 4 * acqTime
                mri.rxGate(expt, t0, acqTime + 2 * addRdPoints / BW)

            # Pre-excitation pulse
            if repeIndex >= dummyPulses and preExTime != 0:
                t0 = tEx - preExTime - inversionTime - rfExTime / 2 - hw.blkTime
                mri.rfRecPulse(expt, t0, rfExTime, rfExAmp / 90 * 90, 0)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             preExTime * 0.5, -0.005, gSteps, axes[0],
                             shimming)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             preExTime * 0.5, -0.005, gSteps, axes[1],
                             shimming)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             preExTime * 0.5, -0.005, gSteps, axes[2],
                             shimming)

            # Inversion pulse
            if repeIndex >= dummyPulses and inversionTime != 0:
                t0 = tEx - inversionTime - rfReTime / 2 - hw.blkTime
                mri.rfRecPulse(expt, t0, rfReTime, rfReAmp / 180 * 180, 0)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             inversionTime * 0.5, 0.005, gSteps, axes[0],
                             shimming)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             inversionTime * 0.5, 0.005, gSteps, axes[1],
                             shimming)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             inversionTime * 0.5, 0.005, gSteps, axes[2],
                             shimming)

            # DC gradient if desired
            if (repeIndex == 0 or repeIndex >= dummyPulses) and dc == True:
                t0 = tEx - 10e3
                mri.gradTrap(expt, t0, gradRiseTime,
                             10e3 + echoSpacing * (etl + 1), rdGradAmplitude,
                             gSteps, axes[0], shimming)

            # Excitation pulse
            t0 = tEx - hw.blkTime - rfExTime / 2
            mri.rfRecPulse(expt, t0, rfExTime, rfExAmp, drfPhase)

            # Dephasing readout
            t0 = tEx + rfExTime / 2 - hw.gradDelay
            if (repeIndex == 0 or repeIndex >= dummyPulses) and dc == False:
                mri.gradTrap(expt, t0, gradRiseTime, rdDephTime,
                             rdDephAmplitude * rdPreemphasis, gSteps, axes[0],
                             shimming)

            # Echo train
            for echoIndex in range(etl):
                tEcho = tEx + echoSpacing * (echoIndex + 1)

                # Refocusing pulse
                t0 = tEcho - echoSpacing / 2 - rfReTime / 2 - hw.blkTime
                mri.rfRecPulse(expt, t0, rfReTime, rfReAmp,
                               drfPhase + np.pi / 2)

                # Dephasing phase and slice gradients
                if repeIndex >= dummyPulses:  # This is to account for dummy pulses
                    t0 = tEcho - echoSpacing / 2 + rfReTime / 2 - hw.gradDelay
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 phGradients[phIndex], gSteps, axes[1],
                                 shimming)
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 slGradients[slIndex], gSteps, axes[2],
                                 shimming)

                # Readout gradient
                if (repeIndex == 0 or repeIndex >= dummyPulses
                    ) and dc == False:  # This is to account for dummy pulses
                    t0 = tEcho - rdGradTime / 2 - gradRiseTime - hw.gradDelay
                    mri.gradTrap(expt, t0, gradRiseTime, rdGradTime,
                                 rdGradAmplitude, gSteps, axes[0], shimming)

                # Rx gate
                if (repeIndex == 0 or repeIndex >= dummyPulses):
                    t0 = tEcho - acqTime / 2 - addRdPoints / BW
                    mri.rxGate(expt, t0, acqTime + 2 * addRdPoints / BW)

                # Rephasing phase and slice gradients
                t0 = tEcho + acqTime / 2 + addRdPoints / BW - hw.gradDelay
                if (echoIndex < etl - 1 and repeIndex >= dummyPulses):
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 -phGradients[phIndex], gSteps, axes[1],
                                 shimming)
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 -slGradients[slIndex], gSteps, axes[2],
                                 shimming)
                elif (echoIndex == etl - 1 and repeIndex >= dummyPulses):
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 +phGradients[phIndex], gSteps, axes[1],
                                 shimming)
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 +slGradients[slIndex], gSteps, axes[2],
                                 shimming)

                # Update the phase and slice gradient
                if repeIndex >= dummyPulses:
                    phIndex += 1

            if repeIndex == nRepetitions - 1:
                mri.endSequence(expt, scanTime)

    # Changing time parameters to us
    rfExTime = rfExTime * 1e6
    rfReTime = rfReTime * 1e6
    echoSpacing = echoSpacing * 1e6
    repetitionTime = repetitionTime * 1e6
    gradRiseTime = gradRiseTime * 1e6
    phGradTime = phGradTime * 1e6
    rdGradTime = rdGradTime * 1e6
    rdDephTime = rdDephTime * 1e6
    inversionTime = inversionTime * 1e6
    preExTime = preExTime * 1e6

    # Calibrate frequency
    if freqCal == 1:
        mri.freqCalibration(rawData, bw=0.05)
        mri.freqCalibration(rawData, bw=0.005)
        larmorFreq = rawData['larmorFreq'] * 1e-6
        drfPhase = rawData['drfPhase']

    # Run the experiment
    dataFull = []
    dummyData = []
    overData = []
    noise = []
    for slIndex in range(nSL):
        expt = ex.Experiment(lo_freq=larmorFreq,
                             rx_t=samplingPeriod,
                             init_gpa=init_gpa,
                             gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
        samplingPeriod = expt.get_rx_ts()[0]
        BW = 1 / samplingPeriod / hw.oversamplingFactor
        acqTime = nPoints[0] / BW  # us
        createSequence()
        for ii in range(nScans):
            print("Scan %s, slice %s ..." % (ii + 1, slIndex + 1))
            rxd, msgs = expt.run()
            rxd['rx0'] = rxd[
                'rx0'] * 13.788  # Here I normalize to get the result in mV
            # Get noise data
            noise = np.concatenate(
                (noise, rxd['rx0'][0:nRD * hw.oversamplingFactor]), axis=0)
            rxd['rx0'] = rxd['rx0'][nRD * hw.oversamplingFactor::]
            # Get data
            if dummyPulses > 0:
                dummyData = np.concatenate(
                    (dummyData,
                     rxd['rx0'][0:nRD * etl * hw.oversamplingFactor]),
                    axis=0)
                overData = np.concatenate(
                    (overData,
                     rxd['rx0'][nRD * etl * hw.oversamplingFactor::]),
                    axis=0)
            else:
                overData = np.concatenate((overData, rxd['rx0']), axis=0)
        expt.__del__()
    print('Scans done!')
    rawData['noiseData'] = noise
    rawData['overData'] = overData

    # Fix the echo position using oversampled data
    if dummyPulses > 0:
        dummyData = np.reshape(
            dummyData, (nSL * nScans, etl, nRD * hw.oversamplingFactor))
        dummyData = np.average(dummyData, axis=0)
        rawData['dummyData'] = dummyData
        overData = np.reshape(
            overData,
            (nScans * nSL, int(nPH / etl), etl, nRD * hw.oversamplingFactor))
        for ii in range(nScans * nSL):
            overData[ii, :, :, :] = mri.fixEchoPosition(
                dummyData, overData[ii, :, :, :])
        overData = np.squeeze(
            np.reshape(overData,
                       (1, nRD * hw.oversamplingFactor * nPH * nSL * nScans)))

    # Generate dataFull
    dataFull = sig.decimate(overData,
                            hw.oversamplingFactor,
                            ftype='fir',
                            zero_phase=True)

    # Get index for krd = 0
    # Average data
    dataProv = np.reshape(dataFull, (nSL, nScans, nRD * nPH))
    dataProv = np.average(dataProv, axis=1)
    # Reorganize the data acording to sweep mode
    dataProv = np.reshape(dataProv, (nSL, nPH, nRD))
    dataTemp = dataProv * 0
    for ii in range(nPH):
        dataTemp[:, ind[ii], :] = dataProv[:, ii, :]
    dataProv = dataTemp
    # Check where is krd = 0
    dataProv = dataProv[int(nPoints[2] / 2), int(nPH / 2), :]
    indkrd0 = np.argmax(np.abs(dataProv))
    if indkrd0 < nRD / 2 - addRdPoints or indkrd0 > nRD / 2 + addRdPoints:
        indkrd0 = int(nRD / 2)
#    indkrd0 = int(nRD/2)

# Get individual images
    dataFull = np.reshape(dataFull, (nSL, nScans, nPH, nRD))
    dataFull = dataFull[:, :, :, indkrd0 - int(nPoints[0] / 2):indkrd0 +
                        int(nPoints[0] / 2)]
    dataTemp = dataFull * 0
    for ii in range(nPH):
        dataTemp[:, :, ind[ii], :] = dataFull[:, :, ii, :]
    dataFull = dataTemp
    imgFull = dataFull * 0
    for ii in range(nScans):
        imgFull[:, ii, :, :] = np.fft.ifftshift(
            np.fft.ifftn(np.fft.ifftshift(np.squeeze(dataFull[:, ii, :, :]))))
    rawData['dataFull'] = dataFull
    rawData['imgFull'] = imgFull

    # Average data
    data = np.average(dataFull, axis=1)

    # Do zero padding
    dataTemp = np.zeros((nPoints[2], nPoints[1], nPoints[0]))
    dataTemp = dataTemp + 1j * dataTemp
    dataTemp[0:nSL, :, :] = data
    data = np.reshape(dataTemp, (1, nPoints[0] * nPoints[1] * nPoints[2]))

    # Fix the position of the sample according to dfov
    kMax = np.array(nPoints) / (2 * np.array(fov)) * np.array(axesEnable)
    kRD = np.linspace(-kMax[0], kMax[0], num=nPoints[0], endpoint=False)
    #        kPH = np.linspace(-kMax[1],kMax[1],num=nPoints[1],endpoint=False)
    kSL = np.linspace(-kMax[2], kMax[2], num=nPoints[2], endpoint=False)
    kPH = kPH[::-1]
    kPH, kSL, kRD = np.meshgrid(kPH, kSL, kRD)
    kRD = np.reshape(kRD, (1, nPoints[0] * nPoints[1] * nPoints[2]))
    kPH = np.reshape(kPH, (1, nPoints[0] * nPoints[1] * nPoints[2]))
    kSL = np.reshape(kSL, (1, nPoints[0] * nPoints[1] * nPoints[2]))
    dPhase = np.exp(-2 * np.pi * 1j *
                    (dfov[0] * kRD + dfov[1] * kPH + dfov[2] * kSL))
    data = np.reshape(data * dPhase, (nPoints[2], nPoints[1], nPoints[0]))
    rawData['kSpace3D'] = data
    img = np.fft.ifftshift(np.fft.ifftn(np.fft.ifftshift(data)))
    rawData['image3D'] = img
    data = np.reshape(data, (1, nPoints[0] * nPoints[1] * nPoints[2]))

    # Create sampled data
    kRD = np.reshape(kRD, (nPoints[0] * nPoints[1] * nPoints[2], 1))
    kPH = np.reshape(kPH, (nPoints[0] * nPoints[1] * nPoints[2], 1))
    kSL = np.reshape(kSL, (nPoints[0] * nPoints[1] * nPoints[2], 1))
    data = np.reshape(data, (nPoints[0] * nPoints[1] * nPoints[2], 1))
    rawData['kMax'] = kMax
    rawData['sampled'] = np.concatenate((kRD, kPH, kSL, data), axis=1)
    data = np.reshape(data, (nPoints[2], nPoints[1], nPoints[0]))

    # Save data
    mri.saveRawData(rawData)

    # Plot data for 1D case
    if (nPH == 1 and nSL == 1):
        # Plot k-space
        plt.figure(3)
        dataPlot = data[0, 0, :]
        plt.subplot(1, 2, 1)
        if axesEnable[0] == 0:
            tVector = np.linspace(
                -acqTime / 2, acqTime / 2, num=nPoints[0],
                endpoint=False) * 1e-3
            sMax = np.max(np.abs(dataPlot))
            indMax = np.argmax(np.abs(dataPlot))
            timeMax = tVector[indMax]
            sMax3 = sMax / 3
            dataPlot3 = np.abs(np.abs(dataPlot) - sMax3)
            indMin = np.argmin(dataPlot3)
            timeMin = tVector[indMin]
            T2 = np.abs(timeMax - timeMin)
            plt.plot(tVector, np.abs(dataPlot))
            plt.plot(tVector, np.real(dataPlot))
            plt.plot(tVector, np.imag(dataPlot))
            plt.xlabel('t (ms)')
            plt.ylabel('Signal (mV)')
            print("T2 = %s us" % (T2))
            plt.title(rawData['fileName'])
            plt.legend(['Abs', 'Real', 'Imag'])
        else:
            plt.plot(kRD[:, 0], np.abs(dataPlot))
            plt.yscale('log')
            plt.xlabel('krd (mm^-1)')
            plt.ylabel('Signal (mV)')
            echoTime = np.argmax(np.abs(dataPlot))
            echoTime = kRD[echoTime, 0]
            print("Echo position = %s mm^{-1}" % round(echoTime, 1))
            plt.title(rawData['fileName'])

        # Plot image
        plt.subplot(122)
        img = img[0, 0, :]
        if axesEnable[0] == 0:
            xAxis = np.linspace(
                -BW / 2, BW / 2, num=nPoints[0], endpoint=False) * 1e3
            plt.plot(xAxis, np.abs(img), '.')
            plt.xlabel('Frequency (kHz)')
            plt.ylabel('Density (a.u.)')
            print("Smax = %s mV" % (np.max(np.abs(img))))
            plt.title(rawData['fileName'])
        else:
            xAxis = np.linspace(-fov[0] / 2 * 1e2,
                                fov[0] / 2 * 1e2,
                                num=nPoints[0],
                                endpoint=False)
            plt.plot(xAxis, np.abs(img))
            plt.xlabel('Position RD (cm)')
            plt.ylabel('Density (a.u.)')
            plt.title(rawData['fileName'])
    else:
        # Plot k-space
        plt.figure(3)
        dataPlot = data[round(nSL / 2), :, :]
        plt.subplot(131)
        plt.imshow(np.log(np.abs(dataPlot)), cmap='gray')
        plt.axis('off')
        # Plot image
        if sweepMode == 3:
            imgPlot = img[round(nSL / 2), round(nPH / 4):round(3 * nPH / 4), :]
        else:
            imgPlot = img[round(nSL / 2), :, :]
        plt.subplot(132)
        plt.imshow(np.abs(imgPlot), cmap='gray')
        plt.axis('off')
        plt.title(rawData['fileName'])
        plt.subplot(133)
        plt.imshow(np.angle(imgPlot), cmap='gray')
        plt.axis('off')

    # plot full image
    if nSL > 1:
        plt.figure(4)
        img2d = np.zeros((nPoints[1], nPoints[0] * nPoints[2]))
        img2d = img2d + 1j * img2d
        for ii in range(nPoints[2]):
            img2d[:, ii * nPoints[0]:(ii + 1) * nPoints[0]] = img[ii, :, :]
        plt.imshow(np.abs(img2d), cmap='gray')
        plt.axis('off')
        plt.title(rawData['fileName'])

    plt.show()
Exemplo n.º 2
0
def rabiflopStandalone(
    init_gpa=False,
    larmorFreq=3.07953,
    rfExAmp=0.4,
    rfExPhase=0,
    rfExTimeIni=6,
    rfExTimeEnd=60,
    nExTime=20,
    nReadout=100,
    tAdq=4 * 1e3,
    tEcho=40 * 1e3,
    tRepetition=500 * 1e3,
    plotSeq=0,
    pulseShape='Rec',  # 'Rec' for square pulse shape, 'Sinc' for sinc pulse shape
    method='Time',  # 'Amp' -> rfReAmp=2*rfExAmp, 'Time' -> rfReTime=2*rfReTime
    shimming=[-70, -90, 10]):

    # Miscellaneous
    deadTime = 400  # us, time between excitation and first acquisition
    shimming = np.array(shimming) * 1e-4

    # Inputs for rawData
    rawData = {}
    rawData['seqName'] = 'RabiFlops'
    rawData['larmorFreq'] = larmorFreq  # Larmor frequency
    rawData['rfExAmp'] = rfExAmp  # rf excitation pulse amplitude
    rawData['rfExTimeIni'] = rfExTimeIni  # rf excitation pulse time
    rawData['rfExTimeEnd'] = rfExTimeEnd  # rf refocusing pulse time
    rawData['nExTime'] = nExTime
    rawData['echoSpacing'] = tEcho  # time between echoes
    rawData['repetitionTime'] = tRepetition  # TR
    rawData['nReadout'] = nReadout
    rawData['tAdq'] = tAdq
    rawData['pulseShape'] = pulseShape
    rawData['shimming'] = shimming
    rawData['deadTime'] = deadTime * 1e-6

    # Excitation times
    rfExTime = np.linspace(rfExTimeIni, rfExTimeEnd, nExTime, endpoint=True)

    # Refocusing amplitude and time
    if method == 'Time':
        rfReAmp = rfExAmp
        rfReTime = 2 * rfExTime
    elif method == 'Amp':
        rfReAmp = 2 * rfExAmp
        rfReTime = rfExTime
    rawData['rfReAmp'] = rfReAmp
    rawData['rfReTime'] = rfReTime

    #  SPECIFIC FUNCTIONS   ####################################################################################
    def plotData(data, rfExTime, tAdqReal):
        plt.figure(1)
        colors = cm.rainbow(np.linspace(0, 0.8, len(rfExTime)))
        for indexExTime in range(nExTime):
            tPlot = np.linspace(
                -tAdqReal / 2, tAdqReal / 2, nReadout, endpoint='True') * 1e-3
            leg = 'Time = ' + str(np.round(rfExTime[indexExTime])) + 'us'
            plt.plot(tPlot[5:],
                     np.abs(data[indexExTime, 5:]),
                     label=leg,
                     color=colors[indexExTime])
#            plt.plot(tPlot[5:], np.real(data[indexExTime, 5:]))
#            plt.plot(tPlot[5:], np.imag(data[indexExTime, 5:]))
        plt.xlabel('t(ms)')
        plt.ylabel('A(mV)')
        plt.legend()

    def getRabiFlopData(data, rfExTime, tAdqReal):
        for indexExTime in range(nExTime):
            if indexExTime == 0:
                maxEchoes = np.max(np.abs(data[indexExTime, 5:]))
            else:
                maxEchoes = np.append(maxEchoes,
                                      np.max(np.abs(data[indexExTime, 5:])))
        rabiFlopData = np.transpose(np.array([rfExTime, maxEchoes]))
        return rabiFlopData

    def plotRabiFlop(rabiFlopData, name):
        plt.figure(2)
        plt.plot(rabiFlopData[:, 0], rabiFlopData[:, 1])
        plt.xlabel('t(us)')
        plt.ylabel('A(mV)')
        titleRF = 'RF Amp = ' + str(np.real(rfExAmp)) + ';  ' + name
        plt.title(titleRF)
        return rabiFlopData

    #  SEQUENCE  ############################################################################################
    def createSequence():
        # Set shimming
        mri.iniSequence(expt, 20, shimming)

        # Initialize time
        tEx = 20e3

        # Excitation pulse
        t0 = tEx - hw.blkTime - rfExTime[indexExTime] / 2
        if pulseShape == 'Rec':
            mri.rfRecPulse(expt, t0, rfExTime[indexExTime], rfExAmp,
                           rfExPhase * np.pi / 180)
        elif pulseShape == 'Sinc':
            mri.rfSincPulse(expt, t0, rfExTime[indexExTime], 7, rfExAmp,
                            rfExPhase * np.pi / 180)

        # First acquisition
        t0 = tEx + rfExTime[indexExTime] / 2 + deadTime
        mri.rxGate(expt, t0, tAcq)

        # Refocusing pulse
        t0 = tEx + tEcho / 2 - rfReTime[indexExTime] / 2 - hw.blkTime
        if pulseShape == 'Rec':
            mri.rfRecPulse(expt, t0, rfReTime[indexExTime], rfReAmp, np.pi / 2)
        elif pulseShape == 'Sinc':
            mri.rfSincPulse(expt, t0, rfReTime[indexExTime], 7, rfReAmp,
                            np.pi / 2)

        # Second acquisition
        t0 = tEx + tEcho - tAcq / 2
        mri.rxGate(expt, t0, tAcq)

        # End sequence
        mri.endSequence(expt, tRepetition)

    # INIT EXPERIMENT
    dataAll = []
    for indexExTime in range(nExTime):
        BW = nReadout / tAdq
        BWov = BW * hw.oversamplingFactor
        samplingPeriod = 1 / BWov
        expt = ex.Experiment(lo_freq=larmorFreq,
                             rx_t=samplingPeriod,
                             init_gpa=init_gpa,
                             gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
        samplingPeriod = expt.get_rx_ts()[0]
        BW = 1 / samplingPeriod / hw.oversamplingFactor
        tAcq = nReadout / BW
        rawData['bw'] = BW
        createSequence()
        if plotSeq == 0:
            print(indexExTime, '.- Running...')
            rxd, msgs = expt.run()
            expt.__del__()
            print('   End')
            data = sig.decimate(rxd['rx0'] * 13.788,
                                hw.oversamplingFactor,
                                ftype='fir',
                                zero_phase=True)
            dataAll = np.concatenate((dataAll, data), axis=0)
            rawData['dataFull'] = dataAll
        elif plotSeq == 1:
            expt.plot_sequence()
            plt.show()
            expt.__del__()

    if plotSeq == 1:
        expt.plot_sequence()
        plt.show()
        expt.__del__()
    elif plotSeq == 0:
        data = np.reshape(dataAll, (nExTime, 2, nReadout))
        dataFID = np.squeeze(data[:, 0, :])
        dataEcho = np.squeeze(data[:, 1, :])
        plotData(dataEcho, rfExTime, tAcq)
        rabiFlopData = getRabiFlopData(dataEcho, rfExTime, tAcq)
        rawData['rabiFlopData'] = rabiFlopData
        mri.saveRawData(rawData)
        plotRabiFlop(rabiFlopData, rawData['fileName'])
        plt.show()
Exemplo n.º 3
0
def fasttrStandalone(
    init_gpa= False,
    larmorFreq = 3.07968,  # MHz 
    rfExAmp = 0.3,
    rfReAmp = 0.6, 
    rfExTime = 30, # us 
    rfReTime = 60, # us
    acqTime = 4,  # ms
    echoTime = 20, # ms
    repetitionTime =0.8, # s
    nRepetitions = 2, # number of samples
    nRD=50, 
    plotSeq =0,
    shimming=[-70, -90, 10]):                
    
    shimming = np.array(shimming)*1e-4
    
    if rfReTime is None:
        rfReTime = 2*rfExTime
    
    rfExTime = rfExTime*1e-6
    rfReTime = rfReTime*1e-6
    acqTime = acqTime*1e-3
    echoTime = echoTime*1e-3
    
    rawData = {}
    rawData['seqName'] = 'fastTR'
    rawData['larmorFreq'] = larmorFreq*1e6
    rawData['rfExAmp'] = rfExAmp
    rawData['rfReAmp'] = rfReAmp
    rawData['rfExTime'] = rfExTime
    rawData['rfRetime'] = rfReTime
    rawData['repetitionTime'] = repetitionTime
    rawData['nRepetitions'] = nRepetitions
    rawData['acqTime'] = acqTime
    rawData['nRD'] = nRD
    rawData['echoTime'] = echoTime
    
    # Miscellaneous
    gradRiseTime = 200 # us
    crusherTime = 1000 # us
    gSteps = int(gradRiseTime/5)
    axes = np.array([0, 1, 2])
    rawData['gradRiseTime'] = gradRiseTime
    rawData['gSteps'] = gSteps
    
    # Bandwidth and sampling rate
    bw = nRD/acqTime*1e-6 # MHz
    bwov = bw*hw.oversamplingFactor
    samplingPeriod = 1/bwov

    def createSequence():
        # Set shimming
        mri.iniSequence(expt, 20, shimming)
        
        for repeIndex in range(nRepetitions):
            # Initialize time
            tEx = 20e3+repetitionTime*repeIndex
            
            # Excitation pulse
            t0 = tEx-hw.blkTime-rfExTime/2
            mri.rfRecPulse(expt, t0, rfExTime, rfExAmp, 0)
            
#            # Rx gating
#            t0 = tEx+rfExTime/2+hw.deadTime
#            mri.rxGate(expt, t0, acqTime)
            
            # Crusher gradient
            t0 = tEx+echoTime/2-crusherTime/2-gradRiseTime-hw.gradDelay-43
            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps, axes[0], shimming)
            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps, axes[1], shimming)
            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps, axes[2], shimming)
            
            # Refocusing pulse
            t0 = tEx+echoTime/2-rfReTime/2-hw.blkTime
            mri.rfRecPulse(expt, t0, rfReTime, rfReAmp, np.pi/2)
            
            # Rx gating
            t0 = tEx+echoTime-acqTime/2
            mri.rxGate(expt, t0, acqTime)
        
        # End sequence
        mri.endSequence(expt, scanTime)
    
    # Time variables in us
    rfExTime *= 1e6
    rfReTime *= 1e6
    repetitionTime *= 1e6
    echoTime *= 1e6
    scanTime = nRepetitions*repetitionTime # us
    
    expt = ex.Experiment(lo_freq=larmorFreq, rx_t=samplingPeriod, init_gpa=init_gpa, gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
    samplingPeriod = expt.get_rx_ts()[0] # us
    bw = 1/samplingPeriod/hw.oversamplingFactor # MHz
    acqTime = nRD/bw # us
    rawData['samplingPeriod'] = samplingPeriod*1e-6
    rawData['bw'] = bw*1e6
    createSequence()
    
    # Representar Secuencia o tomar los datos.
    data = []
    nn = 1
    if plotSeq==1:                
        expt.plot_sequence()
        plt.show()
        expt.__del__()
    elif plotSeq==0:
        print('Running...')
        for repe in range(nn):
            rxd, msgs = expt.run()
            data = np.concatenate((data, rxd['rx0']*13.788), axis=0)
            if nn>1: time.sleep(20)
        expt.__del__()
        print('Ready!')
        data = sig.decimate(data, hw.oversamplingFactor, ftype='fir', zero_phase=True)
        data = np.reshape(data, (nn, nRD*2))
        data = np.average(data, axis=0)
        rawData['fullData'] = data
        dataIndiv = np.reshape(np.abs(data),  (nRepetitions, nRD))
        print('End')
        
        # Save data
        mri.saveRawData(rawData)
        
        # Plots
        plt.figure(1)
        plt.plot(dataIndiv[0, :])
        plt.plot(dataIndiv[1, :])
        plt.xlabel('Time (a.u.)')
        plt.ylabel('Signal (mV)')
        plt.legend('First echo', 'Second echo')
        plt.title(rawData['fileName'])
        
        ratio = dataIndiv[0, int(nRD/2)]/dataIndiv[1, int(nRD/2)]
        print('Signal ratio = ', ratio)
        
        plt.show()
Exemplo n.º 4
0
def haste(self, plotSeq):
    init_gpa = False  # Starts the gpa
    nScans = self.nScans  # NEX
    larmorFreq = self.larmorFreq  # MHz, Larmor frequency
    rfExAmp = self.rfExAmp  # a.u., rf excitation pulse amplitude
    rfReAmp = self.rfReAmp  # a.u., rf refocusing pulse amplitude
    rfExTime = self.rfExTime  # us, rf excitation pulse time
    rfReTime = self.rfReTime  # us, rf refocusing pulse time
    rfEnvelope = self.rfEnvelope  # 'Rec' -> square pulse, 'Sinc' -> sinc pulse
    echoSpacing = self.echoSpacing  # ms, time between echoes
    inversionTime = self.inversionTime  # ms, Inversion recovery time
    repetitionTime = self.repetitionTime  # ms, TR
    fov = np.array(self.fov)  # mm, FOV along readout, phase and slice
    dfov = np.array(self.dfov)  # mm, displacement of fov center
    nPoints = np.array(
        self.nPoints)  # Number of points along readout, phase and slice
    acqTime = self.acqTime  # ms, acquisition time
    axes = np.array(self.axes)  # 0->x, 1->y and 2->z defined as [rd,ph,sl]
    axesEnable = self.axesEnable  # 1-> Enable, 0-> Disable
    sweepMode = self.sweepMode  # 0->k2k (T2),  1->02k (T1),  2->k20 (T2), 3->Niquist modulated (T2)
    rdGradTime = self.rdGradTime  # ms, readout gradient time
    rdDephTime = self.rdDephTime  # ms, readout dephasing time
    phGradTime = self.phGradTime  # ms, phase and slice dephasing time
    rdPreemphasis = self.rdPreemphasis  # readout dephasing gradient is multiplied by this factor
    ssPreemphasis = self.ssPreemphasis  # slice rephasing gradient is multiplied by this factor
    crusherDelay = self.crusherDelay  # delay of the crusher gradient
    drfPhase = self.drfPhase  # degrees, phase of the excitation pulse
    dummyPulses = self.dummyPulses  # number of dummy pulses for T1 stabilization
    shimming = self.shimming  # a.u.*1e4, shimming along the X,Y and Z axes
    parFourierFraction = self.parFourierFraction  # fraction of acquired k-space along phase direction

    freqCal = True
    demo = False

    # rawData fields
    rawData = {}

    # Conversion of variables to non-multiplied units
    larmorFreq = larmorFreq * 1e6
    rfExTime = rfExTime * 1e-6
    rfReTime = rfReTime * 1e-6
    fov = np.array(fov) * 1e-3
    dfov = np.array(dfov) * 1e-3
    echoSpacing = echoSpacing * 1e-3
    acqTime = acqTime * 1e-3
    shimming = np.array(shimming) * 1e-4
    repetitionTime = repetitionTime * 1e-3
    inversionTime = inversionTime * 1e-3
    rdGradTime = rdGradTime * 1e-3
    rdDephTime = rdDephTime * 1e-3
    phGradTime = phGradTime * 1e-3
    crusherDelay = crusherDelay * 1e-6

    # Inputs for rawData
    rawData['seqName'] = 'HASTE'
    rawData['nScans'] = nScans
    rawData['larmorFreq'] = larmorFreq  # Larmor frequency
    rawData['rfExAmp'] = rfExAmp  # rf excitation pulse amplitude
    rawData['rfReAmp'] = rfReAmp  # rf refocusing pulse amplitude
    rawData['rfExTime'] = rfExTime  # rf excitation pulse time
    rawData['rfReTime'] = rfReTime  # rf refocusing pulse time
    rawData['rfEnvelope'] = rfEnvelope
    rawData['echoSpacing'] = echoSpacing  # time between echoes
    rawData['inversionTime'] = inversionTime  # Inversion recovery time
    rawData['repetitionTime'] = repetitionTime  # TR
    rawData['fov'] = fov  # FOV along readout, phase and slice
    rawData['dfov'] = dfov  # Displacement of fov center
    rawData[
        'nPoints'] = nPoints  # Number of points along readout, phase and slice
    rawData['acqTime'] = acqTime  # Acquisition time
    rawData[
        'axesOrientation'] = axes  # 0->x, 1->y and 2->z defined as [rd,ph,sl]
    rawData['axesEnable'] = axesEnable  # 1-> Enable, 0-> Disable
    rawData[
        'sweepMode'] = sweepMode  # 0->k2k (T2),  1->02k (T1),  2->k20 (T2), 3->Niquist modulated (T2)
    rawData['rdPreemphasis'] = rdPreemphasis
    rawData['ssPreemphasis'] = ssPreemphasis
    rawData['drfPhase'] = drfPhase
    rawData['dummyPulses'] = dummyPulses  # Dummy pulses for T1 stabilization
    rawData['partialFourierFraction'] = parFourierFraction
    rawData['rdDephTime'] = rdDephTime
    rawData['crusherDelay'] = crusherDelay
    rawData['shimming'] = shimming

    # Miscellaneous
    slThickness = fov[2]
    rfSincLobes = 7  # Number of lobes for sinc rf excitation, BW = rfSincLobes/rfTime
    larmorFreq = larmorFreq * 1e-6
    gradRiseTime = 200e-6  # Estimated gradient rise time
    gSteps = int(gradRiseTime * 1e6 / 5)
    addRdPoints = 10  # Initial rd points to avoid artifact at the begining of rd
    if rfReAmp == 0:
        rfReAmp = 2 * rfExAmp
    if rfReTime == 0:
        rfReTime = rfExTime
    resolution = fov / nPoints
    rawData['resolution'] = resolution
    rawData['gradRiseTime'] = gradRiseTime
    rawData['addRdPoints'] = addRdPoints

    # Matrix size
    nRD = nPoints[0] + 2 * addRdPoints
    nPH = nPoints[1] * axesEnable[1] + (1 - axesEnable[1])

    # parAcqLines
    nPHreal = int(nPoints[1] * parFourierFraction)
    parAcqLines = int(nPHreal - nPoints[1] / 2)
    rawData['parAcqLines'] = parAcqLines
    print(parAcqLines)
    del nPHreal

    # BW
    BW = nPoints[0] / acqTime * 1e-6
    BWov = BW * hw.oversamplingFactor
    samplingPeriod = 1 / BWov
    rawData['samplingPeriod'] = samplingPeriod

    # Readout gradient time
    if rdGradTime < acqTime:
        rdGradTime = acqTime
    rawData['rdGradTime'] = rdGradTime

    # Phase de- and re-phasing time
    if phGradTime == 0 or phGradTime > echoSpacing / 2 - rfExTime / 2 - rfReTime / 2 - 2 * gradRiseTime:
        phGradTime = echoSpacing / 2 - rfExTime / 2 - rfReTime / 2 - 2 * gradRiseTime
    rawData['phGradTime'] = phGradTime

    # Slice selection dephasing gradient time
    ssDephGradTime = (rfExTime - gradRiseTime) / 2
    rawData['ssDephGradTime'] = ssDephGradTime

    # Max redaout and phase gradient amplitude
    rdGradAmplitude = nPoints[0] / (hw.gammaB * fov[0] *
                                    acqTime) * axesEnable[0]
    phGradAmplitude = nPH / (2 * hw.gammaB * fov[1] *
                             (phGradTime + gradRiseTime)) * axesEnable[1]
    rawData['rdGradAmplitude'] = rdGradAmplitude
    rawData['phGradAmplitude'] = phGradAmplitude

    # Slice selection gradient
    if rfEnvelope == 'Sinc':
        ssGradAmplitude = rfSincLobes / (hw.gammaB * slThickness *
                                         rfExTime) * axesEnable[2]
    elif rfEnvelope == 'Rec':
        ssGradAmplitude = 1 / (hw.gammaB * slThickness *
                               rfExTime) * axesEnable[2]
    rawData['ssGradAmplitude'] = ssGradAmplitude

    # Readout dephasing amplitude
    rdDephAmplitude = 0.5 * rdGradAmplitude * (gradRiseTime + rdGradTime) / (
        gradRiseTime + rdDephTime)
    rawData['rdDephAmplitude'] = rdDephAmplitude

    # Phase gradient vector
    phGradients = np.linspace(-phGradAmplitude,
                              phGradAmplitude,
                              num=nPH,
                              endpoint=False)

    # Get phase indexes for the given sweep mode
    ind = mri.getIndex(2 * parAcqLines, 2 * parAcqLines, sweepMode)
    ind = ind - parAcqLines + int(nPH / 2)
    ind = np.int32(
        np.concatenate((ind,
                        np.linspace(int(nPH / 2) - parAcqLines - 1,
                                    -1,
                                    num=int(nPH / 2) - parAcqLines,
                                    endpoint=False)),
                       axis=0))
    rawData['sweepOrder'] = ind

    # Now fix the number of phases to partailly acquired k-space
    nPH = (int(nPoints[1] / 2) + parAcqLines) * axesEnable[1] + (1 -
                                                                 axesEnable[1])
    phGradients = phGradients[0:nPH]
    phGradients = phGradients[ind]
    rawData['phGradients'] = phGradients

    def createSequenceDemo():
        nRepetitions = int(1 + dummyPulses)
        scanTime = 20e3 + nRepetitions * repetitionTime
        rawData['scanTime'] = scanTime * 1e-6
        acqPoints = 0
        data = []
        for repeIndex in range(nRepetitions):
            for echoIndex in range(nPH):
                if (repeIndex == 0 or repeIndex >= dummyPulses):
                    acqPoints += nRD * hw.oversamplingFactor
                    data = np.concatenate(
                        (data, np.random.randn(nRD * hw.oversamplingFactor) +
                         1j * np.random.randn(nRD * hw.oversamplingFactor)),
                        axis=0)
        return data, acqPoints

    def createSequence():
        nRepetitions = int(1 + dummyPulses)
        scanTime = 20e3 + nRepetitions * repetitionTime
        rawData['scanTime'] = scanTime * 1e-6
        print('Scan Time = ', (scanTime * 1e-6), 's')
        if rdGradTime == 0:  # Check if readout gradient is dc or pulsed
            dc = True
        else:
            dc = False

        # Set shimming
        mri.iniSequence(expt, 20, shimming)
        for repeIndex in range(nRepetitions):
            # Initialize time
            tEx = 20e3 + repetitionTime * repeIndex + inversionTime

            # Inversion pulse
            if repeIndex >= dummyPulses and inversionTime != 0:
                t0 = tEx - inversionTime - rfReTime / 2 - hw.blkTime
                mri.rfRecPulse(expt, t0, rfReTime, rfReAmp / 180 * 180, 0)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             inversionTime * 0.5, 0.005, gSteps, axes[0],
                             shimming)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             inversionTime * 0.5, 0.005, gSteps, axes[1],
                             shimming)
                mri.gradTrap(expt, t0 + hw.blkTime + rfReTime, gradRiseTime,
                             inversionTime * 0.5, 0.005, gSteps, axes[2],
                             shimming)

            # DC radout gradient if desired
            if (repeIndex == 0 or repeIndex >= dummyPulses) and dc == True:
                t0 = tEx - rfExTime / 2 - gradRiseTime - hw.gradDelay
                mri.gradTrap(expt, t0, echoSpacing * (nPH + 1),
                             rdGradAmplitude, axes[0])

            # Slice selection gradient dephasing
            if (slThickness != 0 and repeIndex >= dummyPulses):
                t0 = tEx - rfExTime / 2 - gradRiseTime - hw.gradDelay
                mri.gradTrap(expt, t0, gradRiseTime, rfExTime, ssGradAmplitude,
                             gSteps, axes[2], shimming)

            # Excitation pulse
            t0 = tEx - hw.blkTime - rfExTime / 2
            if rfEnvelope == 'Rec':
                mri.rfRecPulse(expt, t0, rfExTime, rfExAmp,
                               drfPhase * np.pi / 180)
            elif rfEnvelope == 'Sinc':
                mri.rfSincPulse(expt, t0, rfExTime, rfSincLobes, rfExAmp,
                                drfPhase * np.pi / 180)

            # Slice selection gradient rephasing
            if (slThickness != 0 and repeIndex >= dummyPulses):
                t0 = tEx + rfExTime / 2 + gradRiseTime - hw.gradDelay
                if rfEnvelope == 'Rec':
                    mri.gradTrap(expt, t0, gradRiseTime, 0.,
                                 -ssGradAmplitude * ssPreemphasis, gSteps,
                                 axes[2], shimming)
                elif rfEnvelope == 'Sinc':
                    mri.gradTrap(expt, t0, gradRiseTime, ssDephGradTime,
                                 -ssGradAmplitude * ssPreemphasis, gSteps,
                                 axes[2], shimming)

            # Dephasing readout
            t0 = tEx + rfExTime / 2 - hw.gradDelay
            if (repeIndex == 0 or repeIndex >= dummyPulses) and dc == False:
                mri.gradTrap(expt, t0, gradRiseTime, rdDephTime,
                             rdDephAmplitude * rdPreemphasis, gSteps, axes[0],
                             shimming)

            # Echo train
            for echoIndex in range(nPH):
                tEcho = tEx + echoSpacing * (echoIndex + 1)

                # Crusher gradient
                if repeIndex >= dummyPulses:
                    t0 = tEcho - echoSpacing / 2 - rfReTime / 2 - gradRiseTime - hw.gradDelay - crusherDelay
                    mri.gradTrap(expt, t0, gradRiseTime,
                                 rfReTime + 2 * crusherDelay, ssGradAmplitude,
                                 gSteps, axes[2], shimming)

                # Refocusing pulse
                t0 = tEcho - echoSpacing / 2 - rfReTime / 2 - hw.blkTime
                if rfEnvelope == 'Rec':
                    mri.rfRecPulse(expt, t0, rfReTime, rfReAmp,
                                   np.pi / 2 + drfPhase * np.pi / 180)
                if rfEnvelope == 'Sinc':
                    mri.rfSincPulse(expt, t0, rfReTime, rfSincLobes, rfReAmp,
                                    np.pi / 2 + drfPhase * np.pi / 180)

                # Dephasing phase gradient
                t0 = tEcho - echoSpacing / 2 + rfReTime / 2 - hw.gradDelay
                if repeIndex >= dummyPulses:  # This is to account for dummy pulses
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 phGradients[echoIndex], gSteps, axes[1],
                                 shimming)

                # Readout gradient
                t0 = tEcho - rdGradTime / 2 - gradRiseTime - hw.gradDelay
                if (repeIndex == 0 or repeIndex >= dummyPulses
                    ) and dc == False:  # This is to account for dummy pulses
                    mri.gradTrap(expt, t0, gradRiseTime, rdGradTime,
                                 rdGradAmplitude, gSteps, axes[0], shimming)

                # Rx gate
                if (repeIndex == 0 or repeIndex >= dummyPulses):
                    t0 = tEcho - acqTime / 2 - addRdPoints / BW
                    mri.rxGate(expt, t0, acqTime + 2 * addRdPoints / BW)

                # Rephasing phase and slice gradients
                t0 = tEcho + acqTime / 2 + addRdPoints / BW - hw.gradDelay
                if (echoIndex < nPH - 1 and repeIndex >= dummyPulses):
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 -phGradients[echoIndex], gSteps, axes[1],
                                 shimming)
                elif (echoIndex == nPH - 1 and repeIndex >= dummyPulses):
                    mri.gradTrap(expt, t0, gradRiseTime, phGradTime,
                                 +phGradients[echoIndex], gSteps, axes[1],
                                 shimming)

            if repeIndex == nRepetitions - 1:
                mri.endSequence(expt, scanTime)

    # Changing time parameters to us
    rfExTime = rfExTime * 1e6
    rfReTime = rfReTime * 1e6
    echoSpacing = echoSpacing * 1e6
    repetitionTime = repetitionTime * 1e6
    gradRiseTime = gradRiseTime * 1e6
    phGradTime = phGradTime * 1e6
    rdGradTime = rdGradTime * 1e6
    rdDephTime = rdDephTime * 1e6
    inversionTime = inversionTime * 1e6
    crusherDelay = crusherDelay * 1e6
    ssDephGradTime = ssDephGradTime * 1e6

    # Calibrate frequency
    if not demo and freqCal and (not plotSeq):
        mri.freqCalibration(rawData, bw=0.05)
        mri.freqCalibration(rawData, bw=0.005)
        larmorFreq = rawData['larmorFreq'] * 1e-6

    # Create full sequence
    if not demo:
        expt = ex.Experiment(lo_freq=larmorFreq,
                             rx_t=samplingPeriod,
                             init_gpa=init_gpa,
                             gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
        samplingPeriod = expt.get_rx_ts()[0]
        BW = 1 / samplingPeriod / hw.oversamplingFactor
        acqTime = nPoints[0] / BW  # us
        createSequence()

    # Run the experiment
    dataFull = []
    dummyData = []
    overData = []

    for ii in range(nScans):
        if plotSeq:
            expt.plot_sequence()
            plt.show()
            break
        else:
            print("Scan %s ..." % (ii + 1))
            if not demo:
                rxd, msgs = expt.run()
                rxd['rx0'] = rxd[
                    'rx0'] * 13.788  # Here I normalize to get the result in mV
            else:
                data, acqPoints = createSequenceDemo()
            # Get data
            if not demo:
                if dummyPulses > 0:
                    dummyData = np.concatenate(
                        (dummyData,
                         rxd['rx0'][0:nRD * nPH * hw.oversamplingFactor]),
                        axis=0)
                    overData = np.concatenate(
                        (overData,
                         rxd['rx0'][nRD * nPH * hw.oversamplingFactor::]),
                        axis=0)
                else:
                    overData = np.concatenate((overData, rxd['rx0']), axis=0)
            else:
                if dummyPulses > 0:
                    dummyData = np.concatenate(
                        (dummyData, data[0:nRD * nPH * hw.oversamplingFactor]),
                        axis=0)
                    overData = np.concatenate(
                        (overData, data[nRD * nPH * hw.oversamplingFactor::]),
                        axis=0)
                else:
                    overData = np.concatenate((overData, data), axis=0)
    if not demo: expt.__del__()
    print('Scans done!')
    rawData['overData'] = overData

    # Fix the echo position using oversampled data
    if dummyPulses > 0:
        dummyData = np.reshape(dummyData,
                               (nScans, nPH, nRD * hw.oversamplingFactor))
        dummyData = np.average(dummyData, axis=0)
        rawData['dummyData'] = dummyData
        overData = np.reshape(overData,
                              (nScans, 1, nPH, nRD * hw.oversamplingFactor))
        for ii in range(nScans):
            overData[ii, :, :, :] = mri.fixEchoPosition(
                dummyData, overData[ii, :, :, :])

    # Generate dataFull
    overData = np.squeeze(
        np.reshape(overData, (1, nRD * hw.oversamplingFactor * nPH * nScans)))
    dataFull = sig.decimate(overData,
                            hw.oversamplingFactor,
                            ftype='fir',
                            zero_phase=True)

    # Get index for krd = 0
    # Average data
    dataProv = np.reshape(dataFull, (nScans, nRD * nPH))
    dataProv = np.average(dataProv, axis=0)
    # Reorganize the data acording to sweep mode
    dataProv = np.reshape(dataProv, (nPH, nRD))
    dataTemp = dataProv * 0
    for ii in range(nPH):
        dataTemp[ind[ii], :] = dataProv[ii, :]
    dataProv = dataTemp
    # Check where is krd = 0
    dataProv = dataProv[int(nPoints[1] / 2), :]
    indkrd0 = np.argmax(np.abs(dataProv))
    if indkrd0 < nRD / 2 - addRdPoints or indkrd0 > nRD / 2 + addRdPoints:
        indkrd0 = int(nRD / 2)

    # Get individual images
    dataFull = np.reshape(dataFull, (nScans, nPH, nRD))
    dataFull = dataFull[:, :, indkrd0 - int(nPoints[0] / 2):indkrd0 +
                        int(nPoints[0] / 2)]
    dataTemp = dataFull * 0
    for ii in range(nPH):
        dataTemp[:, ind[ii], :] = dataFull[:, ii, :]
    dataFull = dataTemp
    imgFull = dataFull * 0
    for ii in range(nScans):
        imgFull[ii, :, :] = np.fft.ifftshift(
            np.fft.ifftn(np.fft.ifftshift(dataFull[ii, :, :])))
    rawData['dataFull'] = dataFull
    rawData['imgFull'] = imgFull

    # Average data
    data = np.average(dataFull, axis=0)
    data = np.reshape(data, (nPH, nPoints[0]))

    # Do zero padding
    dataTemp = np.zeros((nPoints[1], nPoints[0]))
    dataTemp = dataTemp + 1j * dataTemp
    dataTemp[0:nPH, :] = data
    data = np.reshape(dataTemp, (1, nPoints[0] * nPoints[1]))

    # Fix the position of the sample according to dfov
    kMax = np.array(nPoints) / (2 * np.array(fov)) * np.array(axesEnable)
    kRD = np.linspace(-kMax[0], kMax[0], num=nPoints[0], endpoint=False)
    kPH = np.linspace(-kMax[1], kMax[1], num=nPoints[1], endpoint=False)
    kPH, kRD = np.meshgrid(kPH, kRD)
    kRD = np.reshape(kRD, (1, nPoints[0] * nPoints[1]))
    kPH = np.reshape(kPH, (1, nPoints[0] * nPoints[1]))
    dPhase = np.exp(-2 * np.pi * 1j * (dfov[0] * kRD + dfov[1] * kPH))
    data = np.reshape(data * dPhase, (nPoints[1], nPoints[0]))
    rawData['kSpace3D'] = data
    img = np.fft.ifftshift(np.fft.ifftn(np.fft.ifftshift(data)))
    rawData['image3D'] = img
    data = np.reshape(data, (1, nPoints[0] * nPoints[1]))

    # Create sampled data
    kRD = np.reshape(kRD, (nPoints[0] * nPoints[1], 1))
    kPH = np.reshape(kPH, (nPoints[0] * nPoints[1], 1))
    data = np.reshape(data, (nPoints[0] * nPoints[1], 1))
    rawData['kMax'] = kMax
    rawData['sampled'] = np.concatenate((kRD, kPH, data), axis=1)
    data = np.reshape(data, -1)

    # Save data
    mri.saveRawData(rawData)

    return rawData, msgs, data, BW
Exemplo n.º 5
0
def rabiflopStandalone(
    init_gpa= False,                 
    larmorFreq = 3.0806, # MHz
    rfExAmp = 0.4, # a.u.
    rfReAmp = 0.8, # a.u.
    rfExTime = 22, # us
    rfReTime = 22, # us 
    nPoints = 100,
    acqTime = 18, # ms
    echoTime = 20, # ms
    repetitionTime = 1000, # ms
    plotSeq = 0, # 0 to run sequence, 1 to plot sequence
    pulseShape = 'Rec',  # 'Rec' for square pulse shape, 'Sinc' for sinc pulse shape
    shimming0 = [-77.5, -70, 7.5], 
    nShimming = 10, # number of samples to sweep in each gradient direction
    dShimming = [2.5, 2.5, 2.5] # shimming step in each direction
    ):
    
    freqCal = 0
    plt.ion()

    # Miscellaneous
    deadTime = 400 # us, time between excitation and first acquisition
    shimming0 = np.array(shimming0)*1e-4
    
    # Varibales to fundamental units
    larmorFreq *= 1e6
    rfExTime *= 1e-6
    rfReTime *= 1e-6
    acqTime *= 1e-3
    echoTime *= 1e-3
    repetitionTime *= 1e-3
    
    # Inputs for rawData
    rawData={}
    rawData['seqName'] = 'ShimmingCal'
    rawData['larmorFreq'] = larmorFreq      # Larmor frequency
    rawData['rfExAmp'] = rfExAmp             # rf excitation pulse amplitude
    rawData['rfReAmp'] = rfReAmp
    rawData['rfExTime'] = rfExTime
    rawData['rfReTime'] = rfReTime
    rawData['nPoints'] = nPoints
    rawData['acqTime'] = acqTime
    rawData['echoTime'] = echoTime
    rawData['repetitionTime'] = repetitionTime
    rawData['pulseShape'] = pulseShape
    rawData['deadTime'] = deadTime*1e-6
    rawData['shimming0'] = shimming0
    rawData['nShimming'] = nShimming
    rawData['dShimming'] = dShimming
    rawData['shimming'] = shimming0
    rawData['addRdPoints'] = 10
    
    # Shimming vectors
    dsx = nShimming*dShimming[0]*1e-4
    dsy = nShimming*dShimming[1]*1e-4
    dsz = nShimming*dShimming[2]*1e-4
    sxVector = np.linspace(shimming0[0]-dsx/2, shimming0[0]+dsx/2, num=nShimming, endpoint=False)
    syVector = np.linspace(shimming0[1]-dsy/2, shimming0[1]+dsy/2, num=nShimming, endpoint=False)
    szVector = np.linspace(shimming0[2]-dsz/2, shimming0[2]+dsz/2, num=nShimming, endpoint=False)
    
    # Bandwidth 
    bw = nPoints/acqTime*1e-6 # MHz
    bwov = bw*hw.oversamplingFactor # MHz
    samplingPeriod = 1/bwov # us
    rawData['bw'] = bw
    rawData['samplingPeriod'] = samplingPeriod
    fVector = np.linspace(-bw/2, bw/2, num=nPoints, endpoint=False)
    
    # Time variables in us and MHz
    larmorFreq *=1e-6
    rfExTime *=1e6
    rfReTime *=1e6
    echoTime *=1e6
    repetitionTime *=1e6
    acqTime *=1e6
    
    #  SEQUENCE  ############################################################################################
    def createSequence(shimming):
        # Set shimming
        mri.iniSequence(expt, 20, shimming)
        
        # Initialize time
        tEx = 20e3
            
        # Excitation pulse
        t0 = tEx-hw.blkTime-rfExTime/2
        if pulseShape=='Rec':
            mri.rfRecPulse(expt, t0, rfExTime, rfExAmp, 0)
        elif pulseShape=='Sinc':
            mri.rfSincPulse(expt, t0, rfExTime, 7, rfExAmp, 0)
        
        # Refocusing pulse
        t0 = tEx+echoTime/2-rfReTime/2-hw.blkTime
        if pulseShape=='Rec':
            mri.rfRecPulse(expt, t0, rfReTime, rfReAmp, np.pi/2)
        elif pulseShape=='Sinc':
            mri.rfSincPulse(expt, t0, rfReTime, 7, rfReAmp, np.pi/2)
        
        # Acquisition window
        t0 = tEx+echoTime-acqTime/2
        mri.rxGate(expt, t0, acqTime)
        
        # End sequence
        mri.endSequence(expt, repetitionTime)
        
        
    
    # Calibrate frequency
    if freqCal==1: 
        mri.freqCalibration(rawData, bw=0.05)
        mri.freqCalibration(rawData, bw=0.005)
        larmorFreq = rawData['larmorFreq']*1e-6
        
    # INIT EXPERIMENT
    dataAll = []
    gx = []
    gy = []
    gz = []
    ppmx = []
    ppmy = []
    ppmz = []
    
    # shimming for Gx
    for sx in sxVector:
        shimming = np.array([sx, shimming0[1], shimming0[2]])
        expt = ex.Experiment(lo_freq=larmorFreq, rx_t=samplingPeriod, init_gpa=init_gpa, gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
        samplingPeriod = expt.get_rx_ts()[0]
        bw = 1/samplingPeriod/hw.oversamplingFactor
        acqTime = nPoints/bw
        rawData['bw'] = bw
        createSequence(shimming)
        if plotSeq==1:
            expt.plot_sequence()
            plt.show(block=False)
            expt.__del__()
        elif plotSeq==0:
            print(shimming*1e4,  '.- Running...')
            rxd, msgs = expt.run()
            expt.__del__()
            data = sig.decimate(rxd['rx0']*13.788, hw.oversamplingFactor, ftype='fir', zero_phase=True)
            fwhm, max = getPeakProperties(fVector, data)
            gx = np.concatenate((gx, np.array([max])), axis=0)
            ppmx = np.concatenate((ppmx, np.array([fwhm/larmorFreq*1e6])), axis=0)
            dataAll = np.concatenate((dataAll, data), axis=0)
            # Plots
            plt.figure(1)
            plt.plot(sx*1e4, max, 'b.')
            plt.figure(2)
            plt.plot(sx*1e4, fwhm/larmorFreq*1e6, 'b.')
            plt.show(block=False)
            plt.pause(0.05)
    idx = np.argmax(gx)
    sxOpt = sxVector[idx]
    
    # shimming for Gy
    for sy in syVector:
        shimming = np.array([sxOpt, sy, shimming0[2]])
        expt = ex.Experiment(lo_freq=larmorFreq, rx_t=samplingPeriod, init_gpa=init_gpa, gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
        samplingPeriod = expt.get_rx_ts()[0]
        bw = 1/samplingPeriod/hw.oversamplingFactor
        acqTime = nPoints/bw
        rawData['bw'] = bw
        createSequence(shimming)
        if plotSeq==1:
            expt.plot_sequence()
            plt.show(block=False)
            expt.__del__()
        elif plotSeq==0:
            print(shimming*1e4,  '.- Running...')
            rxd, msgs = expt.run()
            expt.__del__()
            data = sig.decimate(rxd['rx0']*13.788, hw.oversamplingFactor, ftype='fir', zero_phase=True)
            fwhm, max = getPeakProperties(fVector, data)
            gy = np.concatenate((gy, np.array([max])), axis=0)
            ppmy = np.concatenate((ppmy, np.array([fwhm/larmorFreq*1e6])), axis=0)
            dataAll = np.concatenate((dataAll, data), axis=0)
            plt.figure(1)
            plt.plot(sy*1e4, max, 'g.')
            plt.figure(2)
            plt.plot(sy*1e4, fwhm/larmorFreq*1e6, 'g.')
            plt.show(block=False)
            plt.pause(0.05)
    idx = np.argmax(gy)
    syOpt = syVector[idx]
    
    # shimming for Gz
    for sz in szVector:
        shimming = np.array([sxOpt, syOpt, sz])
        expt = ex.Experiment(lo_freq=larmorFreq, rx_t=samplingPeriod, init_gpa=init_gpa, gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
        samplingPeriod = expt.get_rx_ts()[0]
        bw = 1/samplingPeriod/hw.oversamplingFactor
        acqTime = nPoints/bw
        rawData['bw'] = bw
        createSequence(shimming)
        if plotSeq==1:
            expt.plot_sequence()
            plt.show(block=False)
            expt.__del__()
        elif plotSeq==0:
            print(shimming*1e4,  '.- Running...')
            rxd, msgs = expt.run()
            expt.__del__()
            data = sig.decimate(rxd['rx0']*13.788, hw.oversamplingFactor, ftype='fir', zero_phase=True)
            fwhm, max = getPeakProperties(fVector, data)
            gz = np.concatenate((gz, np.array([max])), axis=0)
            ppmz = np.concatenate((ppmz, np.array([fwhm/larmorFreq*1e6])), axis=0)
            dataAll = np.concatenate((dataAll, data), axis=0)
            plt.figure(1)
            plt.plot(sz*1e4, max, 'r.')
            plt.figure(2)
            plt.plot(sz*1e4, fwhm/larmorFreq*1e6, 'r.')
            plt.show(block=False)
            plt.pause(0.05)
    idx = np.argmax(gz)
    szOpt = szVector[idx]
    rawData['shimming'] = np.array([sxOpt, syOpt, szOpt])
    
    # Get the values for the optimal case
    shimming = np.array([sxOpt, syOpt, szOpt])
#    expt = ex.Experiment(lo_freq=larmorFreq, rx_t=samplingPeriod, init_gpa=init_gpa, gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
#    samplingPeriod = expt.get_rx_ts()[0]
#    bw = 1/samplingPeriod/hw.oversamplingFactor
#    acqTime = nPoints/bw
#    rawData['bw'] = bw
#    createSequence(shimming)
#    if plotSeq==1:
#        expt.plot_sequence()
#        plt.show(block=False)
#        expt.__del__()
#    elif plotSeq==0:
#        print(shimming*1e4,  '.- Running...')
#        rxd, msgs = expt.run()
#        expt.__del__()
#        data = sig.decimate(rxd['rx0']*13.788, hw.oversamplingFactor, ftype='fir', zero_phase=True)
#        fwhm, max = getPeakProperties(fVector, data)
#        plt.figure(1)
#        plt.plot(0, max, 'k.')
#        plt.figure(2)
#        plt.plot(0, fwhm/larmorFreq*1e6, 'k.')
#        plt.show(block=False)
#        plt.pause(0.05)

    # Save data
    mri.saveRawData(rawData)
    plt.figure(3)
    plt.plot(sxVector*1e4, gx, 'b.', 
        syVector*1e4, gy, 'g.', 
        szVector*1e4, gz, 'r.')
    plt.title(rawData['fileName'])
    plt.xlabel('Shimming (a.u.)')
    plt.ylabel('FFT peak amplitude (a.u.)')
    plt.legend(['x Axis', 'y Axis', 'z Axis'])
    
    plt.figure(4)
    plt.plot(sxVector*1e4, ppmx, 'b.', 
        syVector*1e4, ppmy, 'g.', 
        szVector*1e4, ppmz, 'r.')
    plt.title(rawData['fileName'])
    plt.xlabel('Shimming (a.u.)')
    plt.ylabel('Homogeneity (ppm)')
    plt.legend(['x Axis', 'y Axis', 'z Axis'])
    
    print('Best shimming = ', shimming*1e4)
    
    plt.show(block=True)
Exemplo n.º 6
0
def saturationrecoveryStandalone(
        init_gpa=False,
        larmorFreq=3.077,  # MHz 
        rfExAmp=0.4,
        rfReAmp=0.4,
        rfExTime=20,  # us 
        rfReTime=20,  # us
        acqTime=4,  # ms
        echoTime=20,  # ms
        repetitionTime=5,  # s
        tSatIni=0.01,  # s
        tSatFin=0.9,  # s
        nRepetitions=1,  # number of samples
        nRD=100,
        plotSeq=0,
        shimming=[-70, -90, 10]):

    shimming = np.array(shimming) * 1e-4

    if rfReTime is None:
        rfReTime = 2 * rfExTime

    rfExTime = rfExTime * 1e-6
    rfReTime = rfReTime * 1e-6
    acqTime = acqTime * 1e-3
    echoTime = echoTime * 1e-3

    rawData = {}
    rawData['seqName'] = 'inversionRecovery'
    rawData['larmorFreq'] = larmorFreq * 1e6
    rawData['rfExAmp'] = rfExAmp
    rawData['rfReAmp'] = rfReAmp
    rawData['rfExTime'] = rfExTime
    rawData['rfRetime'] = rfReTime
    rawData['repetitionTime'] = repetitionTime
    rawData['tSatIni'] = tSatIni
    rawData['tSatFin'] = tSatFin
    rawData['nRepetitions'] = nRepetitions
    rawData['acqTime'] = acqTime
    rawData['nRD'] = nRD
    rawData['echoTime'] = echoTime

    # Miscellaneous
    gradRiseTime = 200  # us
    crusherTime = 1000  # us
    gSteps = int(gradRiseTime / 5)
    axes = np.array([0, 1, 2])
    rawData['gradRiseTime'] = gradRiseTime
    rawData['gSteps'] = gSteps

    # Bandwidth and sampling rate
    bw = nRD / acqTime * 1e-6  # MHz
    bwov = bw * hw.oversamplingFactor
    samplingPeriod = 1 / bwov

    tSat = np.geomspace(tSatIni, tSatFin, nRepetitions)
    rawData['tSat'] = tSat

    def createSequence():
        # Set shimming
        mri.iniSequence(expt, 20, shimming)

        for repeIndex in range(nRepetitions):
            # Initialize time
            tEx = 20e3 + np.max(tSat) + repetitionTime * repeIndex

            # Inversion time for current iteration
            inversionTime = tSat[repeIndex]

            # Crusher gradient for inversion rf pulse
            #            t0 = tEx-inversionTime-crusherTime/2-gradRiseTime-hw.gradDelay-50
            #            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps, axes[0], shimming)
            #            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps, axes[1], shimming)
            #            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps, axes[2], shimming)

            # Saturation pulse
            t0 = tEx - inversionTime - hw.blkTime - rfReTime / 2
            mri.rfRecPulse(expt, t0, rfReTime, rfReAmp, 0)

            # Spoiler gradients to destroy residual transversal signal detected for ultrashort inversion times
            #            mri.gradTrap(expt, t0+hw.blkTime+rfReTime, gradRiseTime, inversionTime*0.5, 0.005, gSteps, axes[0], shimming)
            #            mri.gradTrap(expt, t0+hw.blkTime+rfReTime, gradRiseTime, inversionTime*0.5, 0.005, gSteps, axes[1], shimming)
            #            mri.gradTrap(expt, t0+hw.blkTime+rfReTime, gradRiseTime, inversionTime*0.5, 0.005, gSteps, axes[2], shimming)

            # Excitation pulse
            t0 = tEx - hw.blkTime - rfExTime / 2
            mri.rfRecPulse(expt, t0, rfExTime, rfExAmp, 0)

            #            # Rx gating
            #            t0 = tEx+rfExTime/2+hw.deadTime
            #            mri.rxGate(expt, t0, acqTime)

            # Crusher gradient
            t0 = tEx + echoTime / 2 - crusherTime / 2 - gradRiseTime - hw.gradDelay - 50
            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps,
                         axes[0], shimming)
            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps,
                         axes[1], shimming)
            mri.gradTrap(expt, t0, gradRiseTime, crusherTime, 0.005, gSteps,
                         axes[2], shimming)

            # Refocusing pulse
            t0 = tEx + echoTime / 2 - rfReTime / 2 - hw.blkTime
            mri.rfRecPulse(expt, t0, rfReTime, rfReAmp, np.pi / 2)

            # Rx gating
            t0 = tEx + echoTime - acqTime / 2
            mri.rxGate(expt, t0, acqTime)

        # End sequence
        mri.endSequence(expt, scanTime)

    # Time variables in us
    rfExTime *= 1e6
    rfReTime *= 1e6
    repetitionTime *= 1e6
    echoTime *= 1e6
    tSat *= 1e6
    scanTime = nRepetitions * repetitionTime  # us

    expt = ex.Experiment(lo_freq=larmorFreq,
                         rx_t=samplingPeriod,
                         init_gpa=init_gpa,
                         gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
    samplingPeriod = expt.get_rx_ts()[0]  # us
    bw = 1 / samplingPeriod / hw.oversamplingFactor  # MHz
    acqTime = nRD / bw  # us
    rawData['samplingPeriod'] = samplingPeriod * 1e-6
    rawData['bw'] = bw * 1e6
    createSequence()

    # Representar Secuencia o tomar los datos.
    tSat1 = np.geomspace(tSatIni, tSatFin, nRepetitions)
    tSat2 = np.geomspace(tSatIni, tSatFin, 10 * nRepetitions)
    if plotSeq == 1:
        expt.plot_sequence()
        plt.show()
        expt.__del__()
    elif plotSeq == 0:
        print('Running...')
        rxd, msgs = expt.run()
        print('End')
        data = rxd['rx0'] * 13.788
        expt.__del__()
        data = sig.decimate(data,
                            hw.oversamplingFactor,
                            ftype='fir',
                            zero_phase=True)
        rawData['fullData'] = data
        dataIndiv = np.reshape(data, (nRepetitions, nRD))
        dataIndiv = np.real(
            dataIndiv[:, int(nRD / 2)] *
            np.exp(-1j * (np.angle(dataIndiv[0, int(nRD / 2)]) + np.pi)))
        results = np.transpose(np.array([tSat1,
                                         dataIndiv / np.max(dataIndiv)]))
        #        results = np.transpose(np.array([tSat1, dataIndiv]))
        rawData['signalVsTime'] = results

        plt.figure(1)
        plt.plot(np.abs(data))
        plt.show()

        # For 1 component
        fitData1, xxx = curve_fit(func1, results[:, 0], results[:, 1])
        print('For one component:')
        print('mA', round(fitData1[0], 1))
        print('T1', round(fitData1[1] * 1e3), ' ms')
        rawData['T11'] = fitData1[1] * 1e3
        rawData['M1'] = fitData1[0]

        # For 2 components
        fitData2, xxx = curve_fit(func2,
                                  results[:, 0],
                                  results[:, 1],
                                  p0=(1, 0.1, 0.5, 0.05),
                                  bounds=(0., 5.))
        print('For two components:')
        print('Ma', round(fitData2[0], 1))
        print('Mb', round(fitData2[2], 1))
        print('T1a', round(fitData2[1] * 1e3), ' ms')
        print('T1b', round(fitData2[3] * 1e3), ' ms')
        rawData['T12'] = [fitData2[1], fitData2[3]]
        rawData['M2'] = [fitData2[0], fitData2[2]]

        # For 3 components
        fitData3, xxx = curve_fit(func3,
                                  results[:, 0],
                                  results[:, 1],
                                  p0=(1, 0.1, 0.5, 0.05, 1, 0.01),
                                  bounds=(0., 5.))
        print('For three components:')
        print('Ma', round(fitData3[0], 1), ' ms')
        print('Mb', round(fitData3[2], 1), ' ms')
        print('Mc', round(fitData3[4], 1), ' ms')
        print('T1a', round(fitData3[1] * 1e3), ' ms')
        print('T1b', round(fitData3[3] * 1e3), ' ms')
        print('T1c', round(fitData3[5] * 1e3), ' ms')
        rawData['T13'] = [fitData3[1], fitData3[3], fitData3[5]]
        rawData['M3'] = [fitData3[0], fitData3[2], fitData3[4]]

        # Save data
        mri.saveRawData(rawData)

        # Plots
        plt.figure(2, figsize=(5, 5))
        plt.plot(results[:, 0], results[:, 1], 'o')
        plt.plot(tSat2, func1(tSat2, *fitData1))
        plt.plot(tSat2, func2(tSat2, *fitData2))
        plt.plot(tSat2, func3(tSat2, *fitData3))
        plt.title(rawData['fileName'])
        plt.xscale('log')
        plt.xlabel('t(s)')
        plt.ylabel('Signal (mV)')
        plt.legend([
            'Experimental', 'Fitting 1 component', 'Fitting 2 components',
            'Fitting 3 components'
        ])
        plt.title(rawData['fileName'])
        plt.show()
def rabiflopStandalone(
    init_gpa=False,
    larmorFreq=3.0806,  # MHz
    rfExAmp=0.4,  # a.u.
    rfReAmp=0.8,  # a.u.
    rfExTime=22,  # us
    rfReTime=22,  # us 
    nPoints=100,
    acqTime=18,  # ms
    echoTime=20,  # ms
    repetitionTime=1000,  # ms
    plotSeq=0,  # 0 to run sequence, 1 to plot sequence
    pulseShape='Rec',  # 'Rec' for square pulse shape, 'Sinc' for sinc pulse shape
    shimming0=[-0, -0, 0],
    nShimming=10,  # number of samples to sweep in each gradient direction
    dShimming=[10, 10, 10]  # shimming step in each direction
):

    freqCal = 1
    plt.ion()

    # Miscellaneous
    deadTime = 400  # us, time between excitation and first acquisition
    shimming0 = np.array(shimming0) * 1e-4
    dShimming = np.array(dShimming) * 1e-4

    # Varibales to fundamental units
    larmorFreq *= 1e6
    rfExTime *= 1e-6
    rfReTime *= 1e-6
    acqTime *= 1e-3
    echoTime *= 1e-3
    repetitionTime *= 1e-3

    # Inputs for rawData
    rawData = {}
    rawData['seqName'] = 'ShimmingCal'
    rawData['larmorFreq'] = larmorFreq  # Larmor frequency
    rawData['rfExAmp'] = rfExAmp  # rf excitation pulse amplitude
    rawData['rfReAmp'] = rfReAmp
    rawData['rfExTime'] = rfExTime
    rawData['rfReTime'] = rfReTime
    rawData['nPoints'] = nPoints
    rawData['acqTime'] = acqTime
    rawData['echoTime'] = echoTime
    rawData['repetitionTime'] = repetitionTime
    rawData['pulseShape'] = pulseShape
    rawData['deadTime'] = deadTime * 1e-6
    rawData['shimming0'] = shimming0
    rawData['nShimming'] = nShimming
    rawData['dShimming'] = dShimming
    rawData['shimming'] = shimming0
    rawData['addRdPoints'] = 10

    # Bandwidth
    bw = nPoints / acqTime * 1e-6  # MHz
    bwov = bw * hw.oversamplingFactor  # MHz
    samplingPeriod = 1 / bwov  # us
    rawData['bw'] = bw
    rawData['samplingPeriod'] = samplingPeriod
    fVector = np.linspace(-bw / 2, bw / 2, num=nPoints, endpoint=False)

    # Time variables in us and MHz
    larmorFreq *= 1e-6
    rfExTime *= 1e6
    rfReTime *= 1e6
    echoTime *= 1e6
    repetitionTime *= 1e6
    acqTime *= 1e6

    #  SEQUENCE  ############################################################################################
    def createSequence(expt, shimming):
        # Set shimming
        mri.iniSequence(expt, 20, shimming)

        # Initialize time
        tEx = 20e3

        # Excitation pulse
        t0 = tEx - hw.blkTime - rfExTime / 2
        if pulseShape == 'Rec':
            mri.rfRecPulse(expt, t0, rfExTime, rfExAmp, 0)
        elif pulseShape == 'Sinc':
            mri.rfSincPulse(expt, t0, rfExTime, 7, rfExAmp, 0)

        # Refocusing pulse
        t0 = tEx + echoTime / 2 - rfReTime / 2 - hw.blkTime
        if pulseShape == 'Rec':
            mri.rfRecPulse(expt, t0, rfReTime, rfReAmp, np.pi / 2)
        elif pulseShape == 'Sinc':
            mri.rfSincPulse(expt, t0, rfReTime, 7, rfReAmp, np.pi / 2)

        # Acquisition window
        t0 = tEx + echoTime - acqTime / 2
        mri.rxGate(expt, t0, acqTime)

        # End sequence
        mri.endSequence(expt, repetitionTime)

    def runExperiment(shimmingExp, samplingRate):
        expt = ex.Experiment(lo_freq=larmorFreq,
                             rx_t=samplingRate,
                             init_gpa=init_gpa,
                             gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
        samplingPeriod = expt.get_rx_ts()[0]
        bw = 1 / samplingPeriod / hw.oversamplingFactor
        acqTime = nPoints / bw
        rawData['acqTime'] = acqTime
        rawData['bw'] = bw
        createSequence(expt, shimmingExp)
        print(shimmingExp * 1e4, '.- Running...')
        rxd, msgs = expt.run()
        expt.__del__()
        data = sig.decimate(rxd['rx0'] * 13.788,
                            hw.oversamplingFactor,
                            ftype='fir',
                            zero_phase=True)
        return (data)

    def sweepAxis(axis):
        # First two samples to determine the sweep direction
        shimmingA = shimming0 * 1
        shimmingB = shimming0 * 1
        shimmingB[axis] = shimming0[axis] + dShimming[axis]
        dataA = runExperiment(shimmingA, samplingPeriod)
        fwhmA, maxA = getPeakProperties(fVector, dataA)
        print('Peak amplitude = ', maxA)
        print('Homogeneity = ', fwhmA / larmorFreq * 1e6, ' ppm \n')
        dataB = runExperiment(shimmingB, samplingPeriod)
        fwhmB, maxB = getPeakProperties(fVector, dataB)
        print('Peak amplitude = ', maxB)
        print('Homogeneity = ', fwhmB / larmorFreq * 1e6, ' ppm \n')
        if maxB < maxA:
            dShimming[axis] = -dShimming[axis]
            maxP = maxB
            maxB = maxA
            maxA = maxP
            shimmingP = shimmingB
            shimmingB = shimmingA
            shimmingA = shimmingP
            del maxP, shimmingP

        # Sweep axis until the max start to goes down
        while maxB > maxA:
            fwhmA = fwhmB
            maxA = maxB
            shimmingA = shimmingB * 1
            shimmingB[axis] += dShimming[axis]
            dataB = runExperiment(shimmingB, samplingPeriod)
            fwhmB, maxB = getPeakProperties(fVector, dataB)
            print('Peak amplitude = ', maxB)
            print('Homogeneity = ', fwhmB / larmorFreq * 1e6, ' ppm \n˘')

        print('Axis ', axis, ' optimized!')

        # Return fwhm and max values
        return (fwhmA, maxA, shimmingA)

    # Calibrate frequency
    if freqCal == 1:
        mri.freqCalibration(rawData, bw=0.05)
        mri.freqCalibration(rawData, bw=0.005)
        larmorFreq = rawData['larmorFreq'] * 1e-6

    for nSweep in range(3):
        for axis in range(3):
            fwhmOpt, maxOpt, shimmingOpt = sweepAxis(axis)
            shimming0 = shimmingOpt
        dShimming /= 2

    # Save data
    mri.saveRawData(rawData)
    #    plt.figure(3)
    #    plt.plot(sxVector*1e4, gx, 'b.',
    #        syVector*1e4, gy, 'g.',
    #        szVector*1e4, gz, 'r.')
    #    plt.title(rawData['fileName'])
    #    plt.xlabel('Shimming (a.u.)')
    #    plt.ylabel('FFT peak amplitude (a.u.)')
    #    plt.legend(['x Axis', 'y Axis', 'z Axis'])

    #    plt.figure(4)
    #    plt.plot(sxVector*1e4, ppmx, 'b.',
    #        syVector*1e4, ppmy, 'g.',
    #        szVector*1e4, ppmz, 'r.')
    #    plt.title(rawData['fileName'])
    #    plt.xlabel('Shimming (a.u.)')
    #    plt.ylabel('Homogeneity (ppm)')
    #    plt.legend(['x Axis', 'y Axis', 'z Axis'])

    print('Best shimming = ', shimming0 * 1e4)

    plt.show(block=True)
Exemplo n.º 8
0
def gre3d(self, plotSeq):
    init_gpa = False,  # Starts the gpa
    nScans = self.nScans  # NEX
    larmorFreq = self.larmorFreq  # MHz, Larmor frequency
    rfExAmp = self.rfExAmp  # a.u. rf excitation pulse amplitude
    rfExTime = self.rfExTime  # us, rf excitation pulse time
    echoTime = self.echoTime  # ms, TE
    repetitionTime = self.repetitionTime  # ms, TR
    fov = self.fov  # mm, FOV along readout, phase and slice
    dfov = self.dfov  # mm, Displacement of fov center
    nPoints = self.nPoints  # Number of points along readout, phase and slice
    acqTime = self.acqTime  # ms, Acquisition time
    axes = self.axes  # 0->x, 1->y and 2->z defined as [rd,ph,sl]
    rdGradTime = self.rdGradTime  # ms, readout rephasing gradient time
    dephGradTime = self.dephGradTime  # ms, Phase and slice dephasing time
    dummyPulses = self.dummyPulses  # Dummy pulses for T1 stabilization
    shimming = self.shimming  # a.u.*1e4, Shimming along the X,Y and Z axes
    parFourierFraction = self.parFourierFractionSl  # fraction of acquired k-space along phase direction
    spoiler = self.spoiler  # set 1 or 0 if you want or do not want to apply spoiler gradients

    freqCal = False
    demo = False

    # rawData fields
    rawData = {}

    # Conversion of variables to non-multiplied units
    larmorFreq = larmorFreq * 1e6
    rfExTime = rfExTime * 1e-6
    fov = np.array(fov) * 1e-3
    dfov = np.array(dfov) * 1e-3
    echoTime = echoTime * 1e-3
    acqTime = acqTime * 1e-3
    shimming = np.array(shimming) * 1e-4
    nPoints = np.array(nPoints)
    repetitionTime = repetitionTime * 1e-3
    rdGradTime = rdGradTime * 1e-3
    dephGradTime = dephGradTime * 1e-3

    # Inputs for rawData
    rawData['seqName'] = self.seq
    rawData['nScans'] = nScans
    rawData['larmorFreq'] = larmorFreq  # Larmor frequency
    rawData['rfExAmp'] = rfExAmp  # rf excitation pulse amplitude
    rawData['rfExTime'] = rfExTime  # rf excitation pulse time
    rawData['echoTime'] = echoTime  # time between echoes
    rawData['repetitionTime'] = repetitionTime  # TR
    rawData['fov'] = fov  # FOV along readout, phase and slice
    rawData['dfov'] = dfov  # Displacement of fov center
    rawData[
        'nPoints'] = nPoints  # Number of points along readout, phase and slice
    rawData['acqTime'] = acqTime  # Acquisition time
    rawData[
        'axesOrientation'] = axes  # 0->x, 1->y and 2->z defined as [rd,ph,sl]
    rawData['rdGradTime'] = rdGradTime
    rawData['dephGradTime'] = dephGradTime
    rawData['dummyPulses'] = dummyPulses  # Dummy pulses for T1 stabilization
    rawData['shimming'] = shimming
    rawData['partialFourierFraction'] = parFourierFraction
    rawData['spoiler'] = spoiler

    # Miscellaneous
    larmorFreq = larmorFreq * 1e-6
    gradRiseTime = 100e-6  # Estimated gradient rise time
    gSteps = int(gradRiseTime * 1e6 / 5) * 0 + 1
    addRdPoints = 5  # Initial rd points to avoid artifact at the begining of rd
    resolution = fov / nPoints
    randFactor = 0.
    axesEnable = np.array([1, 1, 1])
    for ii in range(3):
        if nPoints[ii] == 1: axesEnable[ii] = 0
    if fov[0] > 1 and nPoints[1] == 1: axesEnable[0] = 0
    rawData['randFactor'] = randFactor
    rawData['resolution'] = resolution
    rawData['gradRiseTime'] = gradRiseTime
    rawData['addRdPoints'] = addRdPoints

    # Matrix size
    nRD = nPoints[0] + 2 * addRdPoints
    nPH = nPoints[1]
    nSL = nPoints[2]

    # parAcqLines
    nSLreal = int(nPoints[2] * parFourierFraction)
    parAcqLines = int(nSLreal - nPoints[2] / 2)
    rawData['parAcqLines'] = parAcqLines
    del nSLreal

    # BW
    BW = nPoints[0] / acqTime * 1e-6
    BWov = BW * hw.oversamplingFactor
    samplingPeriod = 1 / BWov
    rawData['samplingPeriod'] = samplingPeriod

    # Check if dephasing grad time is ok
    maxDephGradTime = echoTime - (rfExTime + rdGradTime) - 3 * gradRiseTime
    if dephGradTime == 0 or dephGradTime > maxDephGradTime:
        dephGradTime = maxDephGradTime

    # Max gradient amplitude
    rdGradAmplitude = nPoints[0] / (hw.gammaB * fov[0] * acqTime)
    rdDephAmplitude = -rdGradAmplitude * (rdGradTime + gradRiseTime) / (
        2 * (dephGradTime + gradRiseTime))
    phGradAmplitude = nPH / (2 * hw.gammaB * fov[1] *
                             (dephGradTime + gradRiseTime)) * axesEnable[1]
    slGradAmplitude = nSL / (2 * hw.gammaB * fov[2] *
                             (dephGradTime + gradRiseTime)) * axesEnable[2]
    rawData['rdGradAmplitude'] = rdGradAmplitude
    rawData['rdDephAmplitude'] = rdDephAmplitude
    rawData['phGradAmplitude'] = phGradAmplitude
    rawData['slGradAmplitude'] = slGradAmplitude

    # Phase and slice gradient vector
    phGradients = np.linspace(-phGradAmplitude,
                              phGradAmplitude,
                              num=nPH,
                              endpoint=False)
    slGradients = np.linspace(-slGradAmplitude,
                              slGradAmplitude,
                              num=nSL,
                              endpoint=False)

    # Now fix the number of slices to partailly acquired k-space
    if nPoints[2] == 1:
        nSL = 1
    else:
        nSL = int(nPoints[2] / 2) + parAcqLines
    nRepetitions = nPH * nSL

    # Add random displacemnt to phase encoding lines
    for ii in range(nPH):
        if ii < np.ceil(nPH / 2 - nPH / 20) or ii > np.ceil(nPH / 2 +
                                                            nPH / 20):
            phGradients[ii] = phGradients[ii] + randFactor * np.random.randn()
    kPH = hw.gammaB * phGradients * (gradRiseTime + dephGradTime)
    rawData['phGradients'] = phGradients
    rawData['slGradients'] = slGradients

    # Changing time parameters to us
    rfExTime = rfExTime * 1e6
    echoTime = echoTime * 1e6
    repetitionTime = repetitionTime * 1e6
    gradRiseTime = gradRiseTime * 1e6
    dephGradTime = dephGradTime * 1e6
    rdGradTime = rdGradTime * 1e6
    scanTime = nRepetitions * repetitionTime
    rawData['scanTime'] = scanTime * nSL * 1e-6

    # Create demo
    def createSequenceDemo(phIndex=0, slIndex=0, repeIndexGlobal=0):
        repeIndex = 0
        acqPoints = 0
        orders = 0
        data = []

        if (dummyPulses > 0 and nRD * 3 > hw.maxRdPoints) or (
                dummyPulses == 0 and nRD * 2 > hw.maxRdPoints):
            print(
                'ERROR: Too many acquired points or orders to the red pitaya.')
            return ()

        while acqPoints + nRD <= hw.maxRdPoints and orders <= hw.maxOrders and repeIndexGlobal < nRepetitions:
            # First I do a noise measurement
            if repeIndex == 0:
                acqPoints += nRD
                data = np.concatenate(
                    (data, np.random.randn(nRD * hw.oversamplingFactor)),
                    axis=0)

            # Dephasing readout, phase and slice
            if (repeIndex == 0 or repeIndex >= dummyPulses):
                orders = orders + gSteps * 2
            if repeIndex >= dummyPulses:
                orders = orders + gSteps * 4

            # Rephasing readout gradient
            if (repeIndex == 0 or repeIndex >= dummyPulses):
                orders = orders + gSteps * 2

            # Rx gate
            if (repeIndex == 0 or repeIndex >= dummyPulses):
                acqPoints += nRD
                data = np.concatenate(
                    (data, np.random.randn(nRD * hw.oversamplingFactor)),
                    axis=0)

            # Spoiler
            if (repeIndex == 0 or repeIndex >= dummyPulses):
                orders = orders + gSteps * 2
            if repeIndex >= dummyPulses:
                orders = orders + gSteps * 4

            # Update the phase and slice gradient
            if repeIndex >= dummyPulses:
                if phIndex == nPH - 1:
                    phIndex = 0
                    slIndex += 1
                else:
                    phIndex += 1

            if repeIndex >= dummyPulses:
                repeIndexGlobal += 1  # Update the global repeIndex
            repeIndex += 1  # Update the repeIndex after the ETL

        # Return the output variables
        return (phIndex, slIndex, repeIndexGlobal, acqPoints, data)

    # Create sequence instructions
    def createSequence(phIndex=0, slIndex=0, repeIndexGlobal=0, rewrite=True):
        repeIndex = 0
        acqPoints = 0
        orders = 0

        # check in case of dummy pulse filling the cache
        if (dummyPulses > 0 and nRD * 3 > hw.maxRdPoints) or (
                dummyPulses == 0 and nRD * 2 > hw.maxRdPoints):
            print(
                'ERROR: Too many acquired points or orders to the red pitaya.')
            return ()

        # Set shimming
        mri.iniSequence(expt, 20, shimming, rewrite=rewrite)

        # Run sequence batch
        while acqPoints + nRD <= hw.maxRdPoints and orders <= hw.maxOrders and repeIndexGlobal < nRepetitions:
            # Initialize time
            tEx = 20e3 + repetitionTime * repeIndex

            # First I do a noise measurement
            if repeIndex == 0:
                t0 = tEx - 4 * acqTime
                mri.rxGate(expt, t0, acqTime + 2 * addRdPoints / BW)
                acqPoints += nRD

            # Excitation pulse
            t0 = tEx - hw.blkTime - rfExTime / 2
            mri.rfRecPulse(expt, t0, rfExTime, rfExAmp, 0.)

            # Dephasing readout, phase and slice
            if (repeIndex == 0 or repeIndex >= dummyPulses):
                t0 = tEx + rfExTime / 2 - hw.gradDelay
                mri.gradTrap(expt, t0, gradRiseTime, dephGradTime,
                             rdDephAmplitude, gSteps, axes[0], shimming)
                orders = orders + gSteps * 2
            if repeIndex >= dummyPulses:
                t0 = tEx + rfExTime / 2 - hw.gradDelay
                mri.gradTrap(expt, t0, gradRiseTime, dephGradTime,
                             phGradients[phIndex], gSteps, axes[1], shimming)
                mri.gradTrap(expt, t0, gradRiseTime, dephGradTime,
                             slGradients[slIndex], gSteps, axes[2], shimming)
                orders = orders + gSteps * 4

            # Rephasing readout gradient
            if (repeIndex == 0 or repeIndex >= dummyPulses):
                t0 = tEx + echoTime - rdGradTime / 2 - gradRiseTime - hw.gradDelay
                mri.gradTrap(expt, t0, gradRiseTime, rdGradTime,
                             rdGradAmplitude, gSteps, axes[0], shimming)
                orders = orders + gSteps * 2

            # Rx gate
            if (repeIndex == 0 or repeIndex >= dummyPulses):
                t0 = tEx + echoTime - acqTime / 2 - addRdPoints / BW
                mri.rxGate(expt, t0, acqTime + 2 * addRdPoints / BW)
                acqPoints += nRD

            # Spoiler
            if spoiler:
                t0 = tEx + echoTime + rdGradTime / 2 + gradRiseTime - hw.gradDelay
                mri.gradTrap(expt, t0, gradRiseTime, dephGradTime,
                             -rdDephAmplitude, gSteps, axes[0], shimming)
                orders = orders + gSteps * 2

            # Update the phase and slice gradient
            if repeIndex >= dummyPulses:
                if phIndex == nPH - 1:
                    phIndex = 0
                    slIndex += 1
                else:
                    phIndex += 1

            if repeIndex >= dummyPulses:
                repeIndexGlobal += 1  # Update the global repeIndex
            repeIndex += 1  # Update the repeIndex after the ETL

        # Turn off the gradients after the end of the batch
        mri.endSequence(expt, repeIndex * repetitionTime)

        # Return the output variables
        return (phIndex, slIndex, repeIndexGlobal, acqPoints)

    # Calibrate frequency
    if (not demo) and freqCal and (not plotSeq):
        mri.freqCalibration(rawData, bw=0.05)
        mri.freqCalibration(rawData, bw=0.005)
        larmorFreq = rawData['larmorFreq'] * 1e-6
        drfPhase = rawData['drfPhase']

    # Initialize the experiment
    dataFull = []
    dummyData = []
    overData = []
    noise = []
    nBatches = 0
    repeIndexArray = np.array([0])
    repeIndexGlobal = repeIndexArray[0]
    phIndex = 0
    slIndex = 0
    acqPointsPerBatch = []
    while repeIndexGlobal < nRepetitions:
        nBatches += 1
        if not demo:
            expt = ex.Experiment(lo_freq=larmorFreq,
                                 rx_t=samplingPeriod,
                                 init_gpa=init_gpa,
                                 gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
            samplingPeriod = expt.get_rx_ts()[0]
            BW = 1 / samplingPeriod / hw.oversamplingFactor
            acqTime = nPoints[0] / BW  # us
            phIndex, slIndex, repeIndexGlobal, aa = createSequence(
                phIndex=phIndex,
                slIndex=slIndex,
                repeIndexGlobal=repeIndexGlobal,
                rewrite=False)
            repeIndexArray = np.concatenate(
                (repeIndexArray, np.array([repeIndexGlobal - 1])), axis=0)
            acqPointsPerBatch.append(aa)
            expt.plot_sequence()
        else:
            phIndex, slIndex, repeIndexGlobal, aa, dataA = createSequenceDemo(
                phIndex=phIndex,
                slIndex=slIndex,
                repeIndexGlobal=repeIndexGlobal)
            repeIndexArray = np.concatenate(
                (repeIndexArray, np.array([repeIndexGlobal - 1])), axis=0)
            acqPointsPerBatch.append(aa)

        for ii in range(nScans):
            print('Batch ', nBatches, ', Scan ', ii, ' runing...')
            if not demo:
                if plotSeq == 1:  # What is the meaning of plotSeq??
                    print('Ploting sequence...')
                    expt.plot_sequence()
                    plt.show()
                    expt.__del__()
                    break
                else:
                    rxd, msgs = expt.run()
                    rxd['rx0'] = rxd[
                        'rx0'] * 13.788  # Here I normalize to get the result in mV
                    # Get noise data
                    noise = np.concatenate(
                        (noise, rxd['rx0'][0:nRD * hw.oversamplingFactor]),
                        axis=0)
                    rxd['rx0'] = rxd['rx0'][nRD * hw.oversamplingFactor::]
                    # Get data
                    if dummyPulses > 0:
                        dummyData = np.concatenate(
                            (dummyData,
                             rxd['rx0'][0:nRD * hw.oversamplingFactor]),
                            axis=0)
                        overData = np.concatenate(
                            (overData,
                             rxd['rx0'][nRD * hw.oversamplingFactor::]),
                            axis=0)
                    else:
                        overData = np.concatenate((overData, rxd['rx0']),
                                                  axis=0)
            else:
                data = dataA
                noise = np.concatenate(
                    (noise, data[0:nRD * hw.oversamplingFactor]), axis=0)
                data = data[nRD * hw.oversamplingFactor::]
                # Get data
                if dummyPulses > 0:
                    dummyData = np.concatenate(
                        (dummyData, data[0:nRD * hw.oversamplingFactor]),
                        axis=0)
                    overData = np.concatenate(
                        (overData, data[nRD * hw.oversamplingFactor::]),
                        axis=0)
                else:
                    overData = np.concatenate((overData, data), axis=0)

        if not demo: expt.__del__()
        if plotSeq == 1:
            break
    del aa

    if not plotSeq:
        acqPointsPerBatch = (acqPointsPerBatch - nRD *
                             (dummyPulses > 0) - nRD) * nScans
        print('Scans done!')
        rawData['noiseData'] = noise
        rawData['overData'] = overData

        # Fix the echo position using oversampled data
        if dummyPulses > 0:
            dummyData = np.reshape(
                dummyData, (nBatches * nScans, 1, nRD * hw.oversamplingFactor))
            dummyData = np.average(dummyData, axis=0)
            rawData['dummyData'] = dummyData
            overData = np.reshape(overData,
                                  (-1, 1, nRD * hw.oversamplingFactor))
            overData = mri.fixEchoPosition(dummyData, overData)
            overData = np.reshape(overData, -1)

        # Generate dataFull
        dataFull = sig.decimate(overData,
                                hw.oversamplingFactor,
                                ftype='fir',
                                zero_phase=True)
        if nBatches > 1:
            dataFullA = dataFull[0:sum(acqPointsPerBatch[0:-1])]
            dataFullB = dataFull[sum(acqPointsPerBatch[0:-1])::]

        # Reorganize dataFull
        dataProv = np.zeros([nScans, nSL * nPH * nRD])
        dataProv = dataProv + 1j * dataProv
        dataFull = np.reshape(dataFull, (nBatches, nScans, -1, nRD))
        if nBatches > 1:
            dataFullA = np.reshape(dataFullA, (nBatches - 1, nScans, -1, nRD))
            dataFullB = np.reshape(dataFullB, (1, nScans, -1, nRD))
        for scan in range(nScans):
            if nBatches > 1:
                dataProv[ii, :] = np.concatenate(
                    (np.reshape(dataFullA[:, ii, :, :],
                                -1), np.reshape(dataFullB[:, ii, :, :], -1)),
                    axis=0)
            else:
                dataProv[ii, :] = np.reshape(dataFull[:, ii, :, :], -1)
        dataFull = np.reshape(dataProv, -1)

        # Get index for krd = 0
        # Average data
        dataProv = np.reshape(dataFull, (nScans, nRD * nPH * nSL))
        dataProv = np.average(dataProv, axis=0)
        dataProv = np.reshape(dataProv, (nSL, nPH, nRD))
        # Check where is krd = 0
        dataProv = dataProv[int(nPoints[2] / 2), int(nPH / 2), :]
        indkrd0 = np.argmax(np.abs(dataProv))
        if indkrd0 < nRD / 2 - addRdPoints or indkrd0 > nRD / 2 + addRdPoints:
            indkrd0 = int(nRD / 2)

        # Get individual images
        dataFull = np.reshape(dataFull, (nScans, nSL, nPH, nRD))
        dataFull = dataFull[:, :, :, indkrd0 - int(nPoints[0] / 2):indkrd0 +
                            int(nPoints[0] / 2)]
        imgFull = dataFull * 0
        for ii in range(nScans):
            imgFull[ii, :, :, :] = np.fft.ifftshift(
                np.fft.ifftn(np.fft.ifftshift(dataFull[ii, :, :, :])))
        rawData['dataFull'] = dataFull
        rawData['imgFull'] = imgFull

        # Average data
        data = np.average(dataFull, axis=0)
        data = np.reshape(data, (nSL, nPH, nPoints[0]))

        # Do zero padding
        dataTemp = np.zeros((nPoints[2], nPoints[1], nPoints[0]))
        dataTemp = dataTemp + 1j * dataTemp
        dataTemp[0:nSL, :, :] = data
        data = np.reshape(dataTemp, (1, nPoints[0] * nPoints[1] * nPoints[2]))

        # Fix the position of the sample according to dfov
        kMax = np.array(nPoints) / (2 * np.array(fov)) * np.array(axesEnable)
        kRD = np.linspace(-kMax[0], kMax[0], num=nPoints[0], endpoint=False)
        #        kPH = np.linspace(-kMax[1],kMax[1],num=nPoints[1],endpoint=False)
        kSL = np.linspace(-kMax[2], kMax[2], num=nPoints[2], endpoint=False)
        kPH = kPH[::-1]
        kPH, kSL, kRD = np.meshgrid(kPH, kSL, kRD)
        kRD = np.reshape(kRD, (1, nPoints[0] * nPoints[1] * nPoints[2]))
        kPH = np.reshape(kPH, (1, nPoints[0] * nPoints[1] * nPoints[2]))
        kSL = np.reshape(kSL, (1, nPoints[0] * nPoints[1] * nPoints[2]))
        dPhase = np.exp(-2 * np.pi * 1j *
                        (dfov[0] * kRD + dfov[1] * kPH + dfov[2] * kSL))
        data = np.reshape(data * dPhase, (nPoints[2], nPoints[1], nPoints[0]))
        rawData['kSpace3D'] = data
        img = np.fft.ifftshift(np.fft.ifftn(np.fft.ifftshift(data)))
        rawData['image3D'] = img
        data = np.reshape(data, (1, nPoints[0] * nPoints[1] * nPoints[2]))

        # Create sampled data
        kRD = np.reshape(kRD, (nPoints[0] * nPoints[1] * nPoints[2], 1))
        kPH = np.reshape(kPH, (nPoints[0] * nPoints[1] * nPoints[2], 1))
        kSL = np.reshape(kSL, (nPoints[0] * nPoints[1] * nPoints[2], 1))
        data = np.reshape(data, (nPoints[0] * nPoints[1] * nPoints[2], 1))
        rawData['kMax'] = kMax
        rawData['sampled'] = np.concatenate((kRD, kPH, kSL, data), axis=1)
        data = np.reshape(data, (nPoints[2], nPoints[1], nPoints[0]))

        # Save data
        mri.saveRawData(rawData)

        # Reshape to 0 dimensional
        data = np.reshape(data, -1)

        return rawData, msgs, data, BW
Exemplo n.º 9
0
def fasttrStandalone(
        init_gpa=False,
        larmorFreq=3.07,  # MHz 
        # rfExAmp = 0.2, # RF amplitude in a.u.
    rfExAmp=0.2,
        rfExTime=10000,  # us 
        repetitionTime=0.1,  # s
        nRepetitions=1):  # number of samples

    # Inputs in fundamental units
    rfExTime = rfExTime * 1e-6

    rawData = {}
    rawData['seqName'] = 'autoTuning'
    rawData['larmorFreq'] = larmorFreq * 1e6
    rawData['rfExAmp'] = rfExAmp
    rawData['rfExTime'] = rfExTime
    rawData['repetitionTime'] = repetitionTime
    rawData['nRepetitions'] = nRepetitions

    # Miscellaneous
    shimming = np.array([0, 0, 0])
    plt.ion()

    # Bandwidth and sampling rate
    bw = 0.06  # MHz
    bwov = bw * hw.oversamplingFactor
    samplingPeriod = 1 / bwov

    #*******************************************************
    def createSequence():
        # Set shimming
        mri.iniSequence(expt, 20, shimming)
        t0 = 20
        mri.rfRecPulse(expt, t0, rfExTime, rfExAmp, 0)

        # End sequence
        mri.endSequence(expt, rfExTime + 40)

    #*******************************************************

    #*******************************************************
    def ardToVolt(x):
        # Convert arduino inputs (in ascii format) to voltage (0 to 5 V)
        y = 0
        for ii in range(len(x) - 2):
            y = y + (x[-3 - ii] - 48) * 10**ii
        return np.double(y / 1023 * 5)

    #*******************************************************

    # Time variables in us
    rfExTime *= 1e6

    # Create all possible states
    states = np.array([0, 1])
    nCapacitors = 10
    nStates = 2**nCapacitors
    c2, c1, c3, c4, c5, c6, c7, c8, c9, c10 = np.meshgrid(
        states, states, states, states, states, states, states, states, states,
        states)
    c1 = np.reshape(c1, (nStates, 1))
    c2 = np.reshape(c2, (nStates, 1))
    c3 = np.reshape(c3, (nStates, 1))
    c4 = np.reshape(c4, (nStates, 1))
    c5 = np.reshape(c5, (nStates, 1))
    c6 = np.reshape(c6, (nStates, 1))
    c7 = np.reshape(c7, (nStates, 1))
    c8 = np.reshape(c8, (nStates, 1))
    c9 = np.reshape(c9, (nStates, 1))
    c10 = np.reshape(c10, (nStates, 1))
    states = np.concatenate((c1, c2, c3, c4, c5, c6, c7, c8, c9, c10), axis=1)

    # Convert states to strings
    strStates = []
    for ii in range(nStates):
        currentState = ""
        for jj in range(nCapacitors):
            currentState = currentState + str(states[ii, jj])
        strStates.append(currentState)

    # Create experiment
    arduino = serial.Serial(port='/dev/ttyACM1', baudrate=9600, timeout=1.5)
    expt = ex.Experiment(lo_freq=larmorFreq,
                         rx_t=samplingPeriod,
                         init_gpa=init_gpa,
                         gpa_fhdo_offset_time=(1 / 0.2 / 3.1))
    samplingPeriod = expt.get_rx_ts()[0]  # us
    bw = 1 / samplingPeriod / hw.oversamplingFactor  # MHz
    createSequence()
    voltage = []

    # Initialize the experiment with a few runs
    arduino.write(bytes(strStates[0], 'utf-8'))
    expt.run()
    data = arduino.readline()
    arduino.write(bytes(strStates[0], 'utf-8'))
    expt.run()
    data = arduino.readline()

    # Initialize figure
    plt.figure(1)
    plt.plot(0, 0, 'b.')
    plt.ylabel('Voltage (V)')
    plt.xlabel('Iteration')
    plt.xlim([0, nStates])
    plt.show(block=False)
    plt.pause(0.01)

    # Sweep all states
    count = 0
    t0 = time.time()
    for state in strStates:
        arduino.write(bytes(
            state,
            'utf-8'))  # Send current state through serial port to arduino.
        time.sleep(0.02)
        expt.run()  # Run experiment
        data = arduino.readline(
        )  # After experiment is finished, read data stored in serial port
        voltage.append(
            ardToVolt(data))  # Convert data from (0-1023) to (0-5 V)
        print('Progress: %.2f %%, Voltage = %.3f V' %
              (count / nStates * 100, voltage[-1]))
        # Plots
        plt.plot(count, voltage[-1], 'b.')
        plt.show(block=False)
        plt.pause(0.01)
        # Delay to next repetition (Current version of RFPA needs 10% duty cycle)
        time.sleep(repetitionTime)
        count += 1
    t1 = time.time()
    expt.__del__()
    print('Ready!')
    rawData['voltage'] = voltage
    rawData['states'] = strStates
    print('Elapsed time: %.0f s' % (t1 - t0))

    # Get best state
    idx = np.argmin(voltage)
    arduino.write(bytes(strStates[idx], 'utf-8'))
    print('Best state: ', strStates[idx])
    rawData['optState'] = strStates[idx]
    plt.plot(idx, voltage[idx], 'r.')

    # Save data
    mri.saveRawData(rawData)
    plt.title(rawData['fileName'])

    # Plots
    plt.show(block=True)