def GetHamK3(N=1000):
"""GetHamK3: Get modulation and demodulation functions for the coding scheme
HamK3 - Sq16Sq50.
Args:
N (int): N
Returns:
modFs: NxK matrix
demodFs: NxK matrix
"""
#### Set some parameters
K = 3
maxInstantPowerFactor = 6.
dt = float(TauDefault) / float(N)
#### Allocate modulation and demodulation vectors
modFs = np.zeros((N, K))
demodFs = np.zeros((N, K))
#### Prepare modulation functions
modDuty = 1. / maxInstantPowerFactor
for i in range(0, K):
modFs[0:math.floor(modDuty * N),
i] = maxInstantPowerFactor * AveragePowerDefault
#### Prepare demodulation functions
## Make shape of function
demodDuty = 1. / 2.
for i in range(0, K):
demodFs[0:math.floor(demodDuty * N), i] = 1.
## Apply necessary phase shift
shifts = [0, (1. / 3.) * N, (2. / 3.) * N]
demodFs = Utils.ApplyKPhaseShifts(demodFs, shifts)
return (modFs, demodFs)
def GetSquare(N=1000, K=3, tau=TauDefault, totalEnergy=TotalEnergyDefault):
"""GetCosCos: Get modulation and demodulation functions for sinusoid coding scheme. The shift
between each demod function is 2*pi/k where k can be [3,4,5...]
Args:
N (int): N - Number of Samples
k (int): k - Number of coding function
freqFactor (float): Multiplicative factor to the fundamental frequency we want to use.
Returns:
np.array: modFs
np.array: demodFs
"""
#### Allocate modulation and demodulation vectors
modFs = np.zeros((N, K))
demodFs = np.zeros((N, K))
t = np.linspace(0, 2 * np.pi, N)
dt = float(tau) / float(N)
#### Declare base square function
squareF = (np.cos(t)) >= 0
#### Set each mod/demod pair to its base function and scale modulations
for i in range(0, K):
## No need to apply phase shift to modF
modFs[:, i] = squareF
## Scale modF so that area matches the total energy
modFs[:, i] = Utils.ScaleAreaUnderCurve(modFs[:, i],
dx=dt,
desiredArea=totalEnergy)
## Apply phase shift to demodF
demodFs[:, i] = squareF
#### Apply phase shifts to demodF
shifts = np.arange(0, K) * (float(N) / float(K))
demodFs = Utils.ApplyKPhaseShifts(demodFs, shifts)
#### Return coding scheme
return (modFs, demodFs)
def GetSqSq(N=1000, K=4):
"""GetSqSq: Get modulation and demodulation functions for square coding scheme. The shift
between each demod function is 2*pi/k where k can be [3,4,5...].
Args:
N (int): Number of discrete points in the scheme
k (int): Number of mod/demod function pairs
0.5
Returns:
np.array: modFs
np.array: demodFs
"""
#### Allocate modulation and demodulation vectors
modFs = np.zeros((N, K))
demodFs = np.zeros((N, K))
t = np.linspace(0, 2 * np.pi, N)
dt = float(TauDefault) / float(N)
#### Declare base sin function
sqF = (0.5 * signal.square(t, duty=0.5)) + 0.5
#### Set each mod/demod pair to its base function and scale modulations
for i in range(0, K):
## No need to apply phase shift to modF
modFs[:, i] = sqF
## Scale modF so that area matches the total energy
modFs[:, i] = Utils.ScaleAreaUnderCurve(modFs[:, i],
dx=dt,
desiredArea=TotalEnergyDefault)
## Apply phase shift to demodF
demodFs[:, i] = sqF
#### Apply phase shifts to demodF
shifts = np.arange(0, K) * (float(N) / float(K))
demodFs = Utils.ApplyKPhaseShifts(demodFs, shifts)
#### Return coding scheme
return (modFs, demodFs)
def GetHamK5(N=1000):
"""GetHamK5: Get modulation and demodulation functions for the coding scheme HamK5.
Args:
N (int): N
Returns:
modFs: NxK matrix
demodFs: NxK matrix
"""
#### Set some parameters
K = 5
maxInstantPowerFactor = 30.
dt = float(TauDefault) / float(N)
#### Allocate modulation and demodulation vectors
modFs = np.zeros((N, K))
demodFs = np.zeros((N, K))
#### Prepare modulation functions
modDuty = 1. / maxInstantPowerFactor
for i in range(0, K):
modFs[0:math.floor(modDuty * N),
i] = maxInstantPowerFactor * AveragePowerDefault
#### Prepare demodulation functions
## Make shape of function
demodDuty1 = np.array([15. / 30., 15. / 30.])
shift1 = 15. / 30.
demodDuty2 = np.array([15. / 30., 15. / 30.])
shift2 = 7. / 30.
demodDuty3 = np.array([8. / 30., 8. / 30., 7. / 30., 7. / 30.])
shift3 = 3. / 30.
demodDuty4 = np.array([
4. / 30., 4. / 30., 4. / 30., 4. / 30., 3. / 30., 4. / 30., 4. / 30.,
3. / 30.
])
shift4 = 1. / 30.
demodDuty5 = np.array([
2. / 30., 2. / 30., 2. / 30., 2. / 30., 2. / 30., 2. / 30., 2. / 30.,
3. / 30., 2. / 30., 2. / 30., 2. / 30., 2. / 30., 3. / 30., 2. / 30
])
shift5 = 4. / 30.
shifts = [shift1 * N, shift2 * N, shift3 * N, shift4 * N, shift5 * N]
demodDutys = [demodDuty1, demodDuty2, demodDuty3, demodDuty4, demodDuty5]
for i in range(0, K):
demodDuty = demodDutys[i]
startIndeces = np.floor((np.cumsum(demodDuty) - demodDuty) * N)
endIndeces = startIndeces + np.floor(demodDuty * N) - 1
for j in range(len(demodDuty)):
if ((j % 2) == 0):
demodFs[int(startIndeces[j]):int(endIndeces[j]), i] = 1.
## Apply necessary phase shift
demodFs = Utils.ApplyKPhaseShifts(demodFs, shifts)
return (modFs, demodFs)
