class FieldSwitchingExperiment(Experiment):
""" Field Switching Experimen: measure resistance on Keithley while sweeping AMI430 field
"""
field = FloatParameter(default=0.0, unit="T")
measure_current = FloatParameter(default=3e-6, unit="A")
resistance = OutputConnector(unit="Ohm")
mag = AMI430("192.168.5.109")
keith = Keithley2400("GPIB0::25::INSTR")
def init_instruments(self):
self.keith.triad()
self.keith.conf_meas_res(NPLC=10, res_range=1e5)
self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
self.keith.current = self.measure_current.value
self.mag.ramp()
self.measure_current.assign_method(self.keith.set_current)
self.field.assign_method(self.mag.set_field)
self.field.add_post_push_hook(
lambda: time.sleep(0.1)) # Field set delay
async def run(self):
"""This is run for each step in a sweep."""
await self.resistance.push(self.keith.resistance)
logger.debug("Stream has filled {} of {} points".format(
self.resistance.points_taken, self.resistance.num_points()))
await asyncio.sleep(0.02) # Give the filters some time to catch up?
def shutdown_instruments(self):
self.keith.current = 0.0e-5
self.mag.zero()
class SweptTestExperimentMetadata(Experiment):
"""Here the run loop merely spews data until it fills up the stream. """
# Parameters
field = FloatParameter(unit="Oe")
freq = FloatParameter(unit="Hz")
dur = FloatParameter(default=5,unit="ns")
# DataStreams
voltage = OutputConnector()
current = OutputConnector()
# Constants
samples = 5
time_val = 0
def init_instruments(self):
self.field.assign_method(lambda x: logger.debug("Field got value " + str(x)))
self.freq.assign_method(lambda x: logger.debug("Freq got value " + str(x)))
self.dur.assign_method(lambda x: logger.debug("Duration got value " + str(x)))
def init_streams(self):
# Add a "base" data axis: say we are averaging 5 samples per trigger
self.voltage.add_axis(DataAxis("samples", np.array([0,1,2,np.nan,np.nan]), metadata=["data", "data", "data", "0", "1"]))
def __repr__(self):
return "<SweptTestExperimentMetadata>"
async def run(self):
time_step = 0.1
await asyncio.sleep(0.002)
data_row = np.sin(2*np.pi*self.time_val)*np.ones(self.samples) + 0.1*np.random.random(self.samples)
self.time_val += time_step
await self.voltage.push(data_row)
await self.current.push(np.sin(2*np.pi*self.time_val) + 0.1*np.random.random(1))
class SweptTestExperiment(Experiment):
"""Here the run loop merely spews data until it fills up the stream. """
# Parameters
field = FloatParameter(unit="Oe")
freq = FloatParameter(unit="Hz")
dur = FloatParameter(default=5, unit="ns")
# DataStreams
voltage = OutputConnector()
current = OutputConnector()
# Constants
samples = 5
time_val = 0
# Complex?
is_complex = False
def init_instruments(self):
self.field.assign_method(
lambda x: logger.debug("Field got value " + str(x)))
self.freq.assign_method(
lambda x: logger.debug("Freq got value " + str(x)))
self.dur.assign_method(
lambda x: logger.debug("Duration got value " + str(x)))
def init_streams(self):
# Add a "base" data axis: say we are averaging 5 samples per trigger
descrip = DataStreamDescriptor()
descrip.data_name = 'voltage'
if self.is_complex:
descrip.dtype = np.complex128
descrip.add_axis(DataAxis("samples", list(range(self.samples))))
self.voltage.set_descriptor(descrip)
def __repr__(self):
return "<SweptTestExperiment>"
async def run(self):
# logger.debug("Data taker running (inner loop)")
time_step = 0.1
await asyncio.sleep(0.001)
data_row = np.sin(2 * np.pi * self.time_val) * np.ones(
self.samples) + 0.1 * np.random.random(self.samples)
self.time_val += time_step
if self.is_complex:
await self.voltage.push(
np.array(data_row + 0.5j * data_row, dtype=np.complex128))
await self.current.push(
np.array(np.sin(2 * np.pi * self.time_val) +
0.1 * np.random.random(1) +
0.5j * np.random.random(1),
dtype=np.complex128))
else:
await self.voltage.push(data_row)
await self.current.push(
np.sin(2 * np.pi * self.time_val) + 0.1 * np.random.random(1))
class FieldSwitchingLockinExperiment(Experiment):
""" Field Switching Experimen: measure resistance on Keithley while sweeping AMI430 field
"""
field = FloatParameter(default=0.0, unit="T")
# measure_current = FloatParameter(default=3e-6, unit="A")
resistance = OutputConnector(unit="Ohm")
res_reference = 1e3
vsource = 10e-3
mag = AMI430("192.168.5.109")
# keith = Keithley2400("GPIB0::25::INSTR")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
def init_instruments(self):
# Initialize lockin
self.lock.amp = self.vsource
self.lock.tc = 3
self.mag.ramp()
self.delay = self.lock.measure_delay()
self.field.assign_method(self.mag.set_field)
self.field.add_post_push_hook(
lambda: time.sleep(0.1)) # Field set delay
time.sleep(self.delay)
async def run(self):
"""This is run for each step in a sweep."""
await asyncio.sleep(self.delay)
await self.resistance.push(self.res_reference /
((self.lock.amp / self.lock.mag) - 1.0))
def shutdown_instruments(self):
self.mag.zero()
self.lock.amp = 0
class FieldSwitchingLockinExperiment(Experiment):
""" Field Switching Experimen: measure resistance on Keithley while sweeping AMI430 field
"""
field = FloatParameter(default=0.0, unit="T")
resistance = OutputConnector(unit="Ohm")
# Default values for lockin measurement. These will need to be changed in a notebook to match the MR and switching current of the sample being measured
res_reference = 1e3
measure_current = 10e-6
fdB = 18
tc = 100e-3
mag = AMI430("192.168.5.109")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
def init_instruments(self):
# Initialize lockin
self.lock.amp = self.res_reference*self.measure_current
self.lock.tc = self.tc
self.lock.filter_slope = self.fdB
self.mag.ramp()
self.delay = self.lock.measure_delay()
self.field.assign_method(self.mag.set_field)
self.field.add_post_push_hook(lambda: time.sleep(0.1)) # Field set delay
time.sleep(self.delay)
async def run(self):
"""This is run for each step in a sweep."""
await asyncio.sleep(self.delay)
await self.resistance.push(self.res_reference/((self.lock.amp/self.lock.mag)-1.0))
def shutdown_instruments(self):
self.mag.zero()
self.lock.amp = 0
class SweptTestExperiment(Experiment):
"""Here the run loop merely spews data until it fills up the stream. """
# Parameters
field = FloatParameter(unit="Oe")
freq = FloatParameter(unit="Hz")
dur = FloatParameter(default=5,unit="ns")
# DataStreams
voltage = OutputConnector()
current = OutputConnector()
# Constants
samples = 5
time_val = 0
# Complex Values?
complex_data = False
def init_instruments(self):
self.field.assign_method(lambda x: logger.debug("Field got value " + str(x)))
self.freq.assign_method(lambda x: logger.debug("Freq got value " + str(x)))
self.dur.assign_method(lambda x: logger.debug("Duration got value " + str(x)))
def init_streams(self):
# Add a "base" data axis: say we are averaging 5 samples per trigger
self.voltage.add_axis(DataAxis("samples", list(range(self.samples))))
self.current.add_axis(DataAxis("samples", list(range(self.samples))))
def __repr__(self):
return "<SweptTestExperiment>"
def run(self):
logger.debug("Data taker running (inner loop)")
time_step = 0.1
time.sleep(0.002)
if self.complex_data:
data_row = np.sin(2*np.pi*self.time_val)*np.ones(5) + 2.0j*np.sin(2*np.pi*self.time_val)*np.ones(5)
else:
data_row = np.sin(2*np.pi*self.time_val)*np.ones(5) + 0.1*np.random.random(5)
self.time_val += time_step
self.voltage.push(data_row)
self.current.push(data_row*2.0)
logger.debug("Stream pushed points {}.".format(data_row))
logger.debug("Stream has filled {} of {} points".format(self.voltage.points_taken, self.voltage.num_points() ))
class TestExperiment(Experiment):
# Create instances of instruments
fake_instr_1 = TestInstrument1("FAKE::RESOURE::NAME")
fake_instr_2 = TestInstrument2("FAKE::RESOURE::NAME")
fake_instr_3 = TestInstrument3("FAKE::RESOURE::NAME")
# Parameters
freq_1 = FloatParameter(unit="Hz")
freq_2 = FloatParameter(unit="Hz")
# DataStreams
chan1 = OutputConnector()
chan2 = OutputConnector()
# Constants
samples = 3
num_trials = 5
time_val = 0.0
def init_instruments(self):
self.freq_1.assign_method(lambda x: logger.debug("Set: {}".format(x)))
self.freq_2.assign_method(lambda x: logger.debug("Set: {}".format(x)))
def init_streams(self):
# Add "base" data axes
self.chan1.add_axis(DataAxis("samples", list(range(self.samples))))
self.chan2.add_axis(DataAxis("trials", list(range(self.num_trials))))
async def run(self):
logger.debug("Data taker running (inner loop)")
time_step = 0.1
await asyncio.sleep(0.002)
data_row = np.sin(2 * np.pi * self.time_val) * np.ones(
self.samples) + 0.1 * np.random.random(self.samples)
self.time_val += time_step
await self.chan1.push(data_row)
data_row = np.sin(2 * np.pi * self.time_val) * np.ones(
self.num_trials) + 0.1 * np.random.random(self.num_trials)
await self.chan2.push(data_row)
logger.debug("Stream pushed points {}.".format(data_row))
logger.debug("Stream has filled {} of {} points".format(
self.chan1.points_taken, self.chan1.num_points()))
class IcLockinExperiment(Experiment):
""" Nano-wire Ic measurement using Lockin with DC offset
"""
source = FloatParameter(default=0.0, unit="V")
voltage = OutputConnector(unit="V")
current = OutputConnector(unit="A")
resistance = OutputConnector(unit="Ohm")
R_ref = 1e3
sense = 5e-6
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
def init_instruments(self):
# self.keith.triad()
# self.keith.conf_meas_res(NPLC=10, res_range=1e5)
# self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
# self.keith.current = self.measure_current.value
# Initialize lockin
self.lock.amp = self.sense*self.R_ref
#self.lock.tc = self.integration_time
self.delay = self.lock.measure_delay()
# Define source method
self.source.assign_method(self.set_source)
#self.source.add_post_push_hook(lambda: time.sleep(2*self.integration_time))
def set_source(self,source):
self.lock.dc = source
time.sleep(self.lock.measure_delay())
async def run(self):
"""This is run for each step in a sweep."""
await asyncio.sleep(self.delay)
R_load = self.lock.mag/(self.sense - self.lock.mag)*self.R_ref
await self.resistance.push(R_load)
await self.current.push(self.lock.dc/(self.R_ref+R_load))
await self.voltage.push(self.lock.dc*R_load/(self.R_ref+R_load))
logger.debug("Stream has filled {} of {} points".format(self.resistance.points_taken,
self.resistance.num_points() ))
#await asyncio.sleep(2*self.integration_time) # Give the filters some time to catch up?
def shutdown_instruments(self):
self.lock.dc = 0
self.lock.amp = 0
class TestExperiment(Experiment):
# Parameters
freq_1 = FloatParameter(unit="Hz")
freq_2 = FloatParameter(unit="Hz")
# DataStreams
chan1 = OutputConnector()
chan2 = OutputConnector()
# Constants
samples = 3
num_trials = 5
time_val = 0.0
def init_instruments(self):
self.freq_1.assign_method(lambda x: logger.debug("Set: {}".format(x)))
self.freq_2.assign_method(lambda x: logger.debug("Set: {}".format(x)))
def init_streams(self):
self.chan1.add_axis(DataAxis("samples", list(range(self.samples))))
self.chan1.add_axis(DataAxis("trials", list(range(self.num_trials))))
self.chan2.add_axis(DataAxis("samples", list(range(self.samples))))
self.chan2.add_axis(DataAxis("trials", list(range(self.num_trials))))
def run(self):
logger.debug("Data taker running (inner loop)")
time_step = 0.1
time.sleep(0.002)
data_row = np.ones(
self.samples * self.num_trials) + 0.1 * np.random.random(
self.samples * self.num_trials)
self.time_val += time_step
# logger.info(f"IN RUN METHOD PUSHING: {data_row} {data_row.size} {data_row.shape}")
self.chan1.push(data_row)
logger.debug("Stream pushed points {}.".format(data_row))
logger.debug("Stream has filled {} of {} points".format(
self.chan1.points_taken, self.chan1.num_points()))
def set(self, instrs_to_set=[]):
meta_file = compile_to_hardware(self.sequence(),
fileName=self.filename,
axis_descriptor=self.axis_descriptor)
self.exp = QubitExpFactory.create(meta_file=meta_file,
calibration=True,
cw_mode=self.cw_mode)
if self.plot:
# Add the manual plotter and the update method to the experiment
self.exp.add_manual_plotter(self.plot)
self.exp.connect_instruments()
#set instruments for calibration
for instr_to_set in instrs_to_set:
par = FloatParameter()
par.assign_method(
getattr(self.exp._instruments[instr_to_set['instr']],
instr_to_set['method']))
# Either sweep or set single value
if 'sweep_values' in instr_to_set.keys():
par.value = instr_to_set['sweep_values'][0]
self.exp.add_sweep(par, instr_to_set['sweep_values'])
else:
par.value = instr_to_set['value']
par.push()
class SweptTestExperiment(Experiment):
"""Here the run loop merely spews data until it fills up the stream. """
# Parameters
temperature = FloatParameter(unit="K")
# DataStreams
resistance = OutputConnector()
# Constants
samples = 5
time_val = 0
def __repr__(self):
return "<SweptTestExperiment>"
async def run(self):
logger.debug("Data taker running (inner loop)")
await asyncio.sleep(0.002)
def ideal_tc(t, tc=9.0, k=20.0):
return t*1.0/(1.0 + np.exp(-k*(t-tc)))
await self.resistance.push(ideal_tc(self.temperature.value))
class SWERExperiment(Experiment):
""" Experiment class for Switching probability measurment
Determine switching probability for V << V0
with varying V (and durations?)
"""
field = FloatParameter(default=0.0, unit="T")
pulse_duration = FloatParameter(default=1.0e-9, unit="s")
pulse_voltage = FloatParameter(default=0.1, unit="V")
repeats = IntParameter(default = 1) # Dummy parameter for repeating
voltage = OutputConnector()
attempts = 1 << 12
settle_delay = 100e-6
measure_current = 3.0e-6
samps_per_trig = 5
polarity = 1
min_daq_voltage = 0.0
max_daq_voltage = 0.4
reset_amplitude = 0.1
reset_duration = 5.0e-9
mag = AMI430("192.168.5.109")
lock = SR865("USB0::0xB506::0x2000::002638::INSTR")
# pspl = Picosecond10070A("GPIB0::24::INSTR")
arb = KeysightM8190A("192.168.5.108")
keith = Keithley2400("GPIB0::25::INSTR")
def init_streams(self):
# Baked in data axes
descrip = DataStreamDescriptor()
descrip.add_axis(DataAxis("sample", range(self.samps_per_trig)))
descrip.add_axis(DataAxis("state", range(2)))
descrip.add_axis(DataAxis("attempt", range(self.attempts)))
self.voltage.set_descriptor(descrip)
def init_instruments(self):
# ===================
# Setup the Keithley
# ===================
self.keith.triad()
self.keith.conf_meas_res(res_range=1e5)
self.keith.conf_src_curr(comp_voltage=0.5, curr_range=1.0e-5)
self.keith.current = self.measure_current
self.mag.ramp()
# ===================
# Setup the AWG
# ===================
self.arb.set_output(True, channel=1)
self.arb.set_output(False, channel=2)
self.arb.sample_freq = 12.0e9
self.arb.waveform_output_mode = "WSPEED"
self.arb.set_output_route("DC", channel=1)
self.arb.voltage_amplitude = 1.0
self.arb.set_marker_level_low(0.0, channel=1, marker_type="sync")
self.arb.set_marker_level_high(1.5, channel=1, marker_type="sync")
self.arb.continuous_mode = False
self.arb.gate_mode = False
self.setup_arb(self.pulse_voltage.value)
# ===================
# Setup the NIDAQ
# ===================
self.analog_input = Task()
self.read = int32()
self.buf_points = 2*self.samps_per_trig*self.attempts
self.analog_input.CreateAIVoltageChan("Dev1/ai1", "", DAQmx_Val_Diff,
self.min_daq_voltage, self.max_daq_voltage, DAQmx_Val_Volts, None)
self.analog_input.CfgSampClkTiming("", 1e6, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps , self.samps_per_trig)
self.analog_input.CfgInputBuffer(self.buf_points)
self.analog_input.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
self.analog_input.SetStartTrigRetriggerable(1)
self.analog_input.StartTask()
# Assign methods
self.field.assign_method(self.mag.set_field)
self.pulse_voltage.assign_method(self.setup_arb)
def setup_arb(self,volt):
def arb_pulse(amplitude, duration, sample_rate=12e9):
arb_voltage = arb_voltage_lookup()
pulse_points = int(duration*sample_rate)
if pulse_points < 320:
wf = np.zeros(320)
else:
wf = np.zeros(64*np.ceil(pulse_points/64.0))
wf[:pulse_points] = np.sign(amplitude)*arb_voltage(abs(amplitude))
return wf
self.arb.abort()
self.arb.delete_all_waveforms()
self.arb.reset_sequence_table()
# Reset waveform
reset_wf = arb_pulse(-self.polarity*self.reset_amplitude, self.reset_duration)
wf_data = KeysightM8190A.create_binary_wf_data(reset_wf)
rst_segment_id = self.arb.define_waveform(len(wf_data))
self.arb.upload_waveform(wf_data, rst_segment_id)
# Switching waveform
switch_wf = arb_pulse(self.polarity*volt, self.pulse_duration.value)
wf_data = KeysightM8190A.create_binary_wf_data(switch_wf)
sw_segment_id = self.arb.define_waveform(len(wf_data))
self.arb.upload_waveform(wf_data, sw_segment_id)
# NIDAQ trigger waveform
nidaq_trig_wf = KeysightM8190A.create_binary_wf_data(np.zeros(3200), sync_mkr=1)
nidaq_trig_segment_id = self.arb.define_waveform(len(nidaq_trig_wf))
self.arb.upload_waveform(nidaq_trig_wf, nidaq_trig_segment_id)
settle_pts = int(640*np.ceil(self.settle_delay * 12e9 / 640))
scenario = Scenario()
seq = Sequence(sequence_loop_ct=int(self.attempts))
#First try with reset flipping pulse
seq.add_waveform(rst_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
seq.add_waveform(sw_segment_id)
seq.add_idle(settle_pts, 0.0)
seq.add_waveform(nidaq_trig_segment_id)
seq.add_idle(1 << 16, 0.0) # bonus non-contiguous memory delay
scenario.sequences.append(seq)
self.arb.upload_scenario(scenario, start_idx=0)
self.arb.sequence_mode = "SCENARIO"
self.arb.scenario_advance_mode = "REPEAT"
self.arb.scenario_start_index = 0
self.arb.run()
async def run(self):
# Keep track of the previous values
logger.debug("Waiting for filters.")
await asyncio.sleep(1.0)
self.arb.advance()
self.arb.trigger()
buf = np.empty(self.buf_points)
self.analog_input.ReadAnalogF64(self.buf_points, -1, DAQmx_Val_GroupByChannel,
buf, self.buf_points, byref(self.read), None)
await self.voltage.push(buf)
# Seemingly we need to give the filters some time to catch up here...
await asyncio.sleep(0.002)
logger.debug("Stream has filled {} of {} points".format(self.voltage.points_taken, self.voltage.num_points() ))
def shutdown_instruments(self):
self.keith.current = 0.0e-5
# self.mag.zero()
self.arb.stop()
try:
self.analog_input.StopTask()
except Exception as e:
print("Warning: failed to stop task (this normally happens with no consequences when taking multiple samples per trigger).")
pass
class KernelIntegrator(Filter):
sink = InputConnector()
source = OutputConnector()
kernel = Parameter()
bias = FloatParameter(default=0.0)
simple_kernel = BoolParameter(default=True)
box_car_start = FloatParameter(default=0.0)
box_car_stop = FloatParameter(default=100e-9)
frequency = FloatParameter(default=0.0)
"""Integrate with a given kernel. Kernel will be padded/truncated to match record length"""
def __init__(self, **kwargs):
super(KernelIntegrator, self).__init__(**kwargs)
self.pre_int_op = None
self.post_int_op = None
for k, v in kwargs.items():
if hasattr(self, k) and isinstance(getattr(self, k), Parameter):
getattr(self, k).value = v
if "pre_integration_operation" in kwargs:
self.pre_int_op = kwargs["pre_integration_operation"]
if "post_integration_operation" in kwargs:
self.post_int_op = kwargs["post_integration_operation"]
self.quince_parameters = [
self.simple_kernel, self.frequency, self.box_car_start,
self.box_car_stop
]
def update_descriptors(self):
if not self.simple_kernel and self.kernel.value is None:
raise ValueError("Integrator was passed kernel None")
logger.debug(
'Updating KernelIntegrator "%s" descriptors based on input descriptor: %s.',
self.name, self.sink.descriptor)
record_length = self.sink.descriptor.axes[-1].num_points()
if self.simple_kernel.value:
time_pts = self.sink.descriptor.axes[-1].points
time_step = time_pts[1] - time_pts[0]
kernel = np.zeros(record_length, dtype=np.complex128)
sample_start = int(self.box_car_start.value / time_step)
sample_stop = int(self.box_car_stop.value / time_step) + 1
kernel[sample_start:sample_stop] = 1.0
# add modulation
kernel *= np.exp(2j * np.pi * self.frequency.value * time_step *
time_pts)
else:
kernel = eval(self.kernel.value.encode('unicode_escape'))
# pad or truncate the kernel to match the record length
if kernel.size < record_length:
self.aligned_kernel = np.append(
kernel,
np.zeros(record_length - kernel.size, dtype=np.complex128))
else:
self.aligned_kernel = np.resize(kernel, record_length)
# Integrator reduces and removes axis on output stream
# update output descriptors
output_descriptor = DataStreamDescriptor()
# TODO: handle reduction to single point
output_descriptor.axes = self.sink.descriptor.axes[:-1]
output_descriptor._exp_src = self.sink.descriptor._exp_src
output_descriptor.dtype = np.complex128
for os in self.source.output_streams:
os.set_descriptor(output_descriptor)
os.end_connector.update_descriptors()
async def process_data(self, data):
# TODO: handle variable partial records
if self.pre_int_op:
data = self.pre_int_op(data)
filtered = np.inner(np.reshape(data, (-1, len(self.aligned_kernel))),
self.aligned_kernel)
if self.post_int_op:
filtered = self.post_int_op(filtered)
# push to ouptut connectors
for os in self.source.output_streams:
await os.push(filtered)
class KernelIntegrator(Filter):
sink = InputConnector()
source = OutputConnector()
kernel = Parameter()
bias = FloatParameter(default=0.0)
simple_kernel = BoolParameter(default=True)
box_car_start = FloatParameter(default=0.0)
box_car_stop = FloatParameter(default=100e-9)
demod_frequency = FloatParameter(default=0.0)
"""Integrate with a given kernel. Kernel will be padded/truncated to match record length"""
def __init__(self, **kwargs):
super(KernelIntegrator, self).__init__(**kwargs)
self.pre_int_op = None
self.post_int_op = None
for k, v in kwargs.items():
if hasattr(self, k) and isinstance(getattr(self, k), Parameter):
getattr(self, k).value = v
if "pre_integration_operation" in kwargs:
self.pre_int_op = kwargs["pre_integration_operation"]
if "post_integration_operation" in kwargs:
self.post_int_op = kwargs["post_integration_operation"]
# self.quince_parameters = [self.simple_kernel, self.demod_frequency, self.box_car_start, self.box_car_stop]
def update_descriptors(self):
if not self.simple_kernel and self.kernel.value is None:
raise ValueError("Integrator was passed kernel None")
logger.debug(
'Updating KernelIntegrator "%s" descriptors based on input descriptor: %s.',
self.filter_name, self.sink.descriptor)
record_length = self.sink.descriptor.axes[-1].num_points()
if self.kernel.value:
if os.path.exists(
os.path.join(config.KernelDir,
self.kernel.value + '.txt')):
kernel = np.loadtxt(
os.path.join(config.KernelDir, self.kernel.value + '.txt'),
dtype=complex,
converters={
0: lambda s: complex(s.decode().replace('+-', '-'))
})
else:
try:
kernel = eval(self.kernel.value.encode('unicode_escape'))
except:
raise ValueError(
'Kernel invalid. Provide a file name or an expression to evaluate'
)
if self.simple_kernel.value:
logger.warning(
"Using specified kernel. To use a box car filter instead, clear kernel.value"
)
elif self.simple_kernel.value:
time_pts = self.sink.descriptor.axes[-1].points
time_step = time_pts[1] - time_pts[0]
kernel = np.zeros(record_length, dtype=np.complex128)
sample_start = int(self.box_car_start.value / time_step)
sample_stop = int(self.box_car_stop.value / time_step) + 1
kernel[sample_start:sample_stop] = 1.0
# add modulation
kernel *= np.exp(2j * np.pi * self.demod_frequency.value *
time_pts)
else:
raise ValueError(
'Kernel invalid. Either provide a file name or an expression to evaluate or set simple_kernel.value to true'
)
# pad or truncate the kernel to match the record length
if kernel.size < record_length:
self.aligned_kernel = np.append(
kernel,
np.zeros(record_length - kernel.size, dtype=np.complex128))
else:
self.aligned_kernel = np.resize(kernel, record_length)
# Integrator reduces and removes axis on output stream
# update output descriptors
output_descriptor = DataStreamDescriptor()
# TODO: handle reduction to single point
output_descriptor.axes = self.sink.descriptor.axes[:-1]
output_descriptor._exp_src = self.sink.descriptor._exp_src
output_descriptor.dtype = np.complex128
for ost in self.source.output_streams:
ost.set_descriptor(output_descriptor)
ost.end_connector.update_descriptors()
def process_data(self, data):
# TODO: handle variable partial records
if self.pre_int_op:
data = self.pre_int_op(data)
filtered = np.inner(np.reshape(data, (-1, len(self.aligned_kernel))),
self.aligned_kernel)
if self.post_int_op:
filtered = self.post_int_op(filtered)
# push to ouptut connectors
for os in self.source.output_streams:
os.push(filtered)
class Channelizer(Filter):
"""Digital demodulation and filtering to select a particular frequency multiplexed channel"""
sink = InputConnector()
source = OutputConnector()
decimation_factor = IntParameter(value_range=(1, 100), default=2, snap=1)
frequency = FloatParameter(value_range=(-5e9, 5e9),
increment=1.0e6,
default=-9e6)
bandwidth = FloatParameter(value_range=(0.00, 100e6),
increment=0.1e6,
default=5e6)
def __init__(self,
frequency=None,
bandwidth=None,
decimation_factor=None,
**kwargs):
super(Channelizer, self).__init__(**kwargs)
if frequency:
self.frequency.value = frequency
if bandwidth:
self.bandwidth.value = bandwidth
if decimation_factor:
self.decimation_factor.value = decimation_factor
self.quince_parameters = [
self.decimation_factor, self.frequency, self.bandwidth
]
def update_descriptors(self):
logger.debug(
'Updating Channelizer "%s" descriptors based on input descriptor: %s.',
self.name, self.sink.descriptor)
# extract record time sampling
time_pts = self.sink.descriptor.axes[-1].points
self.record_length = len(time_pts)
self.time_step = time_pts[1] - time_pts[0]
logger.debug("Channelizer time_step = {}".format(self.time_step))
# convert bandwidth normalized to Nyquist interval
n_bandwidth = self.bandwidth.value * self.time_step * 2
n_frequency = self.frequency.value * self.time_step * 2
# arbitrarily decide on three stage filter pipeline
# 1. first stage decimating filter on real data
# 2. second stage decimating filter on mixed product to boost n_bandwidth
# 3. final channel selecting filter at n_bandwidth/2
# anecdotally don't decimate more than a factor of eight for stability
self.decim_factors = [1] * 3
self.filters = [None] * 3
# first stage decimating filter
# maximize first stage decimation:
# * minimize subsequent stages time taken
# * filter and decimate while signal is still real
# * first stage decimation cannot be too large or then 2omega signal from mixing will alias
d1 = 1
while (d1 < 8) and (2 * n_frequency <=
0.8 / d1) and (d1 < self.decimation_factor.value):
d1 *= 2
n_bandwidth *= 2
n_frequency *= 2
if d1 > 1:
# create an anti-aliasing filter
# pass-band to 0.8 * decimation factor; anecdotally single precision needs order <= 4 for stability
b, a = scipy.signal.cheby1(4, 3, 0.8 / d1)
b = np.float32(b)
a = np.float32(a)
self.decim_factors[0] = d1
self.filters[0] = (b, a)
# store decimated reference for mix down
ref = np.exp(2j * np.pi * self.frequency.value * time_pts[::d1],
dtype=np.complex64)
self.reference_r = np.real(ref)
self.reference_i = np.imag(ref)
# second stage filter to bring n_bandwidth/2 up
# decimation cannot be too large or will impinge on channel bandwidth (keep n_bandwidth/2 <= 0.8)
d2 = 1
while (d2 < 8) and ((d1 * d2) < self.decimation_factor.value) and (
n_bandwidth / 2 <= 0.8):
d2 *= 2
n_bandwidth *= 2
n_frequency *= 2
if d2 > 1:
# create an anti-aliasing filter
# pass-band to 0.8 * decimation factor; anecdotally single precision needs order <= 4 for stability
b, a = scipy.signal.cheby1(4, 3, 0.8 / d2)
b = np.float32(b)
a = np.float32(a)
self.decim_factors[1] = d2
self.filters[1] = (b, a)
# final channel selection filter
if n_bandwidth < 0.1:
raise ValueError(
"Insufficient decimation to achieve stable filter")
b, a = scipy.signal.cheby1(4, 3, n_bandwidth / 2)
b = np.float32(b)
a = np.float32(a)
self.decim_factors[2] = self.decimation_factor.value // (d1 * d2)
self.filters[2] = (b, a)
# update output descriptors
decimated_descriptor = DataStreamDescriptor()
decimated_descriptor.axes = self.sink.descriptor.axes[:]
decimated_descriptor.axes[-1] = deepcopy(self.sink.descriptor.axes[-1])
decimated_descriptor.axes[-1].points = self.sink.descriptor.axes[
-1].points[self.decimation_factor.value -
1::self.decimation_factor.value]
decimated_descriptor.axes[
-1].original_points = decimated_descriptor.axes[-1].points
decimated_descriptor.exp_src = self.sink.descriptor.exp_src
decimated_descriptor.dtype = np.complex64
for os in self.source.output_streams:
os.set_descriptor(decimated_descriptor)
if os.end_connector is not None:
os.end_connector.update_descriptors()
async def process_data(self, data):
# Assume for now we get a integer number of records at a time
# TODO: handle partial records
num_records = data.size // self.record_length
reshaped_data = np.reshape(data, (num_records, self.record_length),
order="C")
# first stage decimating filter
if self.filters[0] is not None:
stacked_coeffs = np.concatenate(self.filters[0])
# filter
filtered = np.empty_like(reshaped_data)
libipp.filter_records_iir(stacked_coeffs,
self.filters[0][0].size - 1,
reshaped_data, self.record_length,
num_records, filtered)
# decimate
if self.decim_factors[0] > 1:
filtered = filtered[:, ::self.decim_factors[0]]
# mix with reference
# keep real and imaginary separate for filtering below
filtered_r = self.reference_r * filtered
filtered_i = self.reference_i * filtered
# channel selection filters
for ct in [1, 2]:
if self.filters[ct] == None:
continue
coeffs = self.filters[ct]
stacked_coeffs = np.concatenate(self.filters[ct])
out_r = np.empty_like(filtered_r)
out_i = np.empty_like(filtered_i)
libipp.filter_records_iir(stacked_coeffs,
self.filters[ct][0].size - 1, filtered_r,
filtered_r.shape[-1], num_records, out_r)
libipp.filter_records_iir(stacked_coeffs,
self.filters[ct][0].size - 1, filtered_i,
filtered_i.shape[-1], num_records, out_i)
# decimate
if self.decim_factors[ct] > 1:
filtered_r = np.copy(out_r[:, ::self.decim_factors[ct]],
order="C")
filtered_i = np.copy(out_i[:, ::self.decim_factors[ct]],
order="C")
else:
filtered_r = out_r
filtered_i = out_i
filtered = filtered_r + 1j * filtered_i
# recover gain from selecting single sideband
filtered *= 2
# push to ouptut connectors
for os in self.source.output_streams:
await os.push(filtered)
class Averager(Filter):
"""Takes data and collapses along the specified axis."""
sink = InputConnector()
partial_average = OutputConnector()
source = OutputConnector()
final_variance = OutputConnector()
final_counts = OutputConnector()
axis = Parameter()
threshold = FloatParameter()
def __init__(self, axis=None, threshold=0.5, **kwargs):
super(Averager, self).__init__(**kwargs)
self.axis.value = axis
self.threshold.value = threshold
self.points_before_final_average = None
self.points_before_partial_average = None
self.sum_so_far = None
self.num_averages = None
self.passthrough = False
# Rate limiting for partial averages
self.last_update = time.time()
self.update_interval = 0.5
def update_descriptors(self):
logger.debug(
'Updating averager "%s" descriptors based on input descriptor: %s.',
self.filter_name, self.sink.descriptor)
descriptor_in = self.sink.descriptor
names = [a.name for a in descriptor_in.axes]
self.axis.allowed_values = names
if self.axis.value is None:
self.axis.value = descriptor_in.axes[0].name
# Convert named axes to an index
if self.axis.value not in names:
raise ValueError(
"Could not find axis {} within the DataStreamDescriptor {}".
format(self.axis.value, descriptor_in))
self.axis_num = descriptor_in.axis_num(self.axis.value)
logger.debug("Averaging over axis #%d: %s", self.axis_num,
self.axis.value)
self.data_dims = descriptor_in.data_dims()
# If we only have a single point along this axis, then just pass the data straight through
if self.data_dims[self.axis_num] == 1:
logger.debug("Averaging over a singleton axis")
self.passthrough = True
if self.axis_num == len(descriptor_in.axes) - 1:
logger.debug("Performing scalar average!")
self.points_before_partial_average = 1
self.avg_dims = [1]
else:
self.points_before_partial_average = descriptor_in.num_points_through_axis(
self.axis_num + 1)
self.avg_dims = self.data_dims[self.axis_num + 1:]
# If we get multiple final average simultaneously
self.reshape_dims = self.data_dims[self.axis_num:]
if self.axis_num > 0:
self.reshape_dims = [-1] + self.reshape_dims
self.mean_axis = self.axis_num - len(self.data_dims)
self.points_before_final_average = descriptor_in.num_points_through_axis(
self.axis_num)
logger.debug("Points before partial average: %s.",
self.points_before_partial_average)
logger.debug("Points before final average: %s.",
self.points_before_final_average)
logger.debug("Data dimensions are %s", self.data_dims)
logger.debug("Averaging dimensions are %s", self.avg_dims)
# Define final axis descriptor
descriptor = descriptor_in.copy()
self.num_averages = descriptor.pop_axis(self.axis.value).num_points()
logger.debug("Number of partial averages is %d", self.num_averages)
if len(descriptor.axes) == 0:
# We will be left with only a single point here!
descriptor.add_axis(DataAxis("result", [0]))
self.sum_so_far = np.zeros(self.avg_dims, dtype=descriptor.dtype)
self.current_avg_frame = np.zeros(self.points_before_final_average,
dtype=descriptor.dtype)
self.partial_average.descriptor = descriptor
self.source.descriptor = descriptor
self.excited_counts = np.zeros(self.data_dims, dtype=np.int64)
# We can update the visited_tuples upfront if none
# of the sweeps are adaptive...
desc_out_dtype = descriptor_in.axis_data_type(
with_metadata=True, excluding_axis=self.axis.value)
if not descriptor_in.is_adaptive():
vals = [
a.points_with_metadata() for a in descriptor_in.axes
if a.name != self.axis.value
]
nested_list = list(itertools.product(*vals))
flattened_list = [
tuple((val for sublist in line for val in sublist))
for line in nested_list
]
descriptor.visited_tuples = np.core.records.fromrecords(
flattened_list, dtype=desc_out_dtype)
else:
descriptor.visited_tuples = np.empty((0), dtype=desc_out_dtype)
for stream in self.partial_average.output_streams:
stream.set_descriptor(descriptor)
stream.descriptor.buffer_mult_factor = 20
stream.end_connector.update_descriptors()
for stream in self.source.output_streams:
stream.set_descriptor(descriptor)
stream.end_connector.update_descriptors()
# Define variance axis descriptor
descriptor_var = descriptor_in.copy()
descriptor_var.data_name = "Variance"
descriptor_var.pop_axis(self.axis.value)
if descriptor_var.unit:
descriptor_var.unit = descriptor_var.unit + "^2"
descriptor_var.metadata["num_averages"] = self.num_averages
self.final_variance.descriptor = descriptor_var
# Define counts axis descriptor
descriptor_count = descriptor_in.copy()
descriptor_count.data_name = "Counts"
descriptor_count.dtype = np.float64
descriptor_count.pop_axis(self.axis.value)
descriptor_count.add_axis(DataAxis("state", [0, 1]), position=0)
if descriptor_count.unit:
descriptor_count.unit = "counts"
descriptor_count.metadata["num_counts"] = self.num_averages
self.final_counts.descriptor = descriptor_count
if not descriptor_in.is_adaptive():
descriptor_var.visited_tuples = np.core.records.fromrecords(
flattened_list, dtype=desc_out_dtype)
else:
descriptor_var.visited_tuples = np.empty((0), dtype=desc_out_dtype)
for stream in self.final_variance.output_streams:
stream.set_descriptor(descriptor_var)
stream.end_connector.update_descriptors()
for stream in self.final_counts.output_streams:
stream.set_descriptor(descriptor_count)
stream.end_connector.update_descriptors()
def final_init(self):
if self.points_before_final_average is None:
raise Exception(
"Average has not been initialized. Run 'update_descriptors'")
self.completed_averages = 0
self.idx_frame = 0
self.idx_global = 0
# We only need to accumulate up to the averaging axis
# BUT we may get something longer at any given time!
self.carry = np.zeros(0, dtype=self.source.descriptor.dtype)
def process_data(self, data):
if self.passthrough:
for os in self.source.output_streams:
os.push(data)
for os in self.final_variance.output_streams:
os.push(data * 0.0)
for os in self.partial_average.output_streams:
os.push(data)
return
# TODO: handle unflattened data separately
if len(data.shape) > 1:
data = data.flatten()
#handle single points
elif not isinstance(data, np.ndarray) and (data.size == 1):
data = np.array([data])
if self.carry.size > 0:
data = np.concatenate((self.carry, data))
self.carry = np.zeros(0, dtype=self.source.descriptor.dtype)
idx = 0
while idx < data.size:
#check whether we have enough data to fill an averaging frame
if data.size - idx >= self.points_before_final_average:
#logger.debug("Have {} points, enough for final avg.".format(data.size))
# How many chunks can we process at once?
num_chunks = int(
(data.size - idx) / self.points_before_final_average)
new_points = num_chunks * self.points_before_final_average
reshaped = data[idx:idx + new_points].reshape(
self.reshape_dims)
averaged = reshaped.mean(axis=self.mean_axis)
idx += new_points
# do state assignment
excited_states = (np.real(reshaped) >
self.threshold.value).sum(
axis=self.mean_axis)
ground_states = self.num_averages - excited_states
if self.sink.descriptor.is_adaptive():
new_tuples = self.sink.descriptor.tuples(
)[self.idx_global:self.idx_global + new_points]
new_tuples_stripped = remove_fields(
new_tuples, self.axis.value)
take_axis = -1 if self.axis_num > 0 else 0
reduced_tuples = new_tuples_stripped.reshape(
self.reshape_dims).take((0, ), axis=take_axis)
self.idx_global += new_points
# Add to Visited tuples
if self.sink.descriptor.is_adaptive():
for os in self.source.output_streams + self.final_variance.output_streams + self.partial_average.output_streams:
os.descriptor.visited_tuples = np.append(
os.descriptor.visited_tuples, reduced_tuples)
for os in self.source.output_streams:
os.push(averaged)
for os in self.final_variance.output_streams:
os.push(reshaped.var(axis=self.mean_axis,
ddof=1)) # N-1 in the denominator
for os in self.partial_average.output_streams:
os.push(averaged)
for os in self.final_counts.output_streams:
os.push(ground_states)
os.push(excited_states)
# Maybe we can fill a partial frame
elif data.size - idx >= self.points_before_partial_average:
# logger.info("Have {} points, enough for partial avg.".format(data.size))
# How many chunks can we process at once?
num_chunks = int(
(data.size - idx) / self.points_before_partial_average)
new_points = num_chunks * self.points_before_partial_average
# Find the appropriate dimensions for the partial
partial_reshape_dims = self.reshape_dims[:]
partial_reshape_dims[self.mean_axis] = -1
partial_reshape_dims = partial_reshape_dims[self.mean_axis:]
reshaped = data[idx:idx +
new_points].reshape(partial_reshape_dims)
summed = reshaped.sum(axis=self.mean_axis)
self.sum_so_far += summed
self.current_avg_frame[self.idx_frame:self.idx_frame +
new_points] = data[idx:idx + new_points]
idx += new_points
self.idx_frame += new_points
self.completed_averages += num_chunks
# If we now have enoough for the final average, push to both partial and final...
if self.completed_averages == self.num_averages:
reshaped = self.current_avg_frame.reshape(
partial_reshape_dims)
for os in self.source.output_streams + self.partial_average.output_streams:
os.push(reshaped.mean(axis=self.mean_axis))
for os in self.final_variance.output_streams:
os.push(
np.real(reshaped).var(axis=self.mean_axis,
ddof=1) + 1j *
np.imag(reshaped).var(axis=self.mean_axis, ddof=1)
) # N-1 in the denominator
# do state assignment
excited_states = (np.real(reshaped) <
self.threshold.value).sum(
axis=self.mean_axis)
ground_states = self.num_averages - excited_states
for os in self.final_counts.output_streams:
os.push(ground_states)
os.push(excited_states)
self.sum_so_far[:] = 0.0
self.current_avg_frame[:] = 0.0
self.completed_averages = 0
self.idx_frame = 0
else:
# Emit a partial average since we've accumulated enough data
if (time.time() - self.last_update >=
self.update_interval):
for os in self.partial_average.output_streams:
os.push(self.sum_so_far / self.completed_averages)
self.last_update = time.time()
# otherwise just add it to the carry
else:
self.carry = data[idx:]
break
class WindowIntegrator(Filter):
"""
Allow a kernel from the set {'chebwin', 'blackman', 'slepian',
'boxcar'} to be set for the duration of the start and stop values.
YAML parameters are:
type: WindowIntegrator
source: Demod-q1
kernel_type: 'chebwin'
start: 5.0e-07
stop: 9.0e-07
See: https://docs.scipy.org/doc/scipy/reference/signal.html for more
details on the filters specifics.
"""
sink = InputConnector()
source = OutputConnector()
bias = FloatParameter(default=0.0)
kernel_type = Parameter(default='boxcar', allowed_values=['chebwin',\
'blackman', 'slepian', 'boxcar'])
start = FloatParameter(default=0.0)
stop = FloatParameter(default=100e-9)
frequency = FloatParameter(default=0.0)
"""Integrate with a given kernel. Kernel will be padded/truncated to match record length"""
def __init__(self, **kwargs):
super(WindowIntegrator, self).__init__(**kwargs)
self.pre_int_op = None
self.post_int_op = None
for k, v in kwargs.items():
if hasattr(self, k) and isinstance(getattr(self, k), Parameter):
getattr(self, k).value = v
if "pre_integration_operation" in kwargs:
self.pre_int_op = kwargs["pre_integration_operation"]
if "post_integration_operation" in kwargs:
self.post_int_op = kwargs["post_integration_operation"]
self.quince_parameters = [
self.kernel_type, self.frequency, self.start, self.stop
]
def update_descriptors(self):
if not self.kernel_type:
raise ValueError("Integrator was passed kernel None")
logger.debug(
'Updating WindowIntegrator "%s" descriptors based on input descriptor: %s.',
self.name, self.sink.descriptor)
record_length = self.sink.descriptor.axes[-1].num_points()
time_pts = self.sink.descriptor.axes[-1].points
time_step = time_pts[1] - time_pts[0]
kernel = np.zeros(record_length, dtype=np.complex128)
sample_start = int(self.box_car_start.value / time_step)
sample_stop = int(self.box_car_stop.value / time_step) + 1
if self.kernel_type == 'boxcar':
kernel[sample_start:sample_stop] = 1.0
elif self.kernel_type == 'chebwin':
# create a Dolph-Chebyshev window with 100 dB attenuation
kernel[sample_start:sample_stop] = \
chebwin(sample_start-sample_stop, at=100)
elif self.kernel_type == 'blackman':
kernel[sample_start:sample_stop] = \
blackman(sample_start-sample_stop)
elif self.kernel_type == 'slepian':
# create a Slepian window with 0.2 bandwidth
kernel[sample_start:sample_stop] = \
slepian(sample_start-sample_stop, width=0.2)
# add modulation
kernel *= np.exp(2j * np.pi * self.frequency.value * time_step *
time_pts)
# pad or truncate the kernel to match the record length
if kernel.size < record_length:
self.aligned_kernel = np.append(
kernel,
np.zeros(record_length - kernel.size, dtype=np.complex128))
else:
self.aligned_kernel = np.resize(kernel, record_length)
# Integrator reduces and removes axis on output stream
# update output descriptors
output_descriptor = DataStreamDescriptor()
# TODO: handle reduction to single point
output_descriptor.axes = self.sink.descriptor.axes[:-1]
output_descriptor._exp_src = self.sink.descriptor._exp_src
output_descriptor.dtype = np.complex128
for os in self.source.output_streams:
os.set_descriptor(output_descriptor)
os.end_connector.update_descriptors()
async def process_data(self, data):
# TODO: handle variable partial records
if self.pre_int_op:
data = self.pre_int_op(data)
filtered = np.inner(np.reshape(data, (-1, len(self.aligned_kernel))),
self.aligned_kernel)
if self.post_int_op:
filtered = self.post_int_op(filtered)
# push to ouptut connectors
for os in self.source.output_streams:
await os.push(filtered)
class Channelizer(Filter):
"""Digital demodulation and filtering to select a particular frequency multiplexed channel. If
an axis name is supplied to `follow_axis` then the filter will demodulate at the freqency
`axis_frequency_value - follow_freq_offset` otherwise it will demodulate at `frequency`. Note that
the filter coefficients are still calculated with respect to the `frequency` paramter, so it should
be chosen accordingly when `follow_axis` is defined."""
sink = InputConnector()
source = OutputConnector()
follow_axis = Parameter(default="") # Name of the axis to follow
follow_freq_offset = FloatParameter(default=0.0) # Offset
decimation_factor = IntParameter(value_range=(1, 100), default=4, snap=1)
frequency = FloatParameter(value_range=(-10e9, 10e9),
increment=1.0e6,
default=10e6)
bandwidth = FloatParameter(value_range=(0.00, 100e6),
increment=0.1e6,
default=5e6)
def __init__(self,
frequency=None,
bandwidth=None,
decimation_factor=None,
follow_axis=None,
follow_freq_offset=None,
**kwargs):
super(Channelizer, self).__init__(**kwargs)
if frequency:
self.frequency.value = frequency
if bandwidth:
self.bandwidth.value = bandwidth
if decimation_factor:
self.decimation_factor.value = decimation_factor
if follow_axis:
self.follow_axis.value = follow_axis
if follow_freq_offset:
self.follow_freq_offset.value = follow_freq_offset
self.quince_parameters = [
self.decimation_factor, self.frequency, self.bandwidth
]
self._phase = 0.0
def final_init(self):
self.init_filters(self.frequency.value, self.bandwidth.value)
if self.follow_axis.value is not "":
desc = self.sink.descriptor
axis_num = desc.axis_num(self.follow_axis.value)
self.pts_before_freq_update = desc.num_points_through_axis(
axis_num + 1)
self.pts_before_freq_reset = desc.num_points_through_axis(axis_num)
self.demod_freqs = desc.axes[
axis_num].points - self.follow_freq_offset.value
self.current_freq = 0
self.update_references(self.current_freq)
self.idx = 0
# For storing carryover if getting uneven buffers
self.carry = np.zeros(0, dtype=self.output_descriptor.dtype)
def update_references(self, frequency):
# store decimated reference for mix down
# phase_drift = 2j*np.pi*0.5e-6 * (abs(frequency) - 100e6)
ref = np.exp(2j * np.pi * -frequency * self.time_pts[::self.d1] +
1j * self._phase,
dtype=np.complex64)
self.reference = ref
self.reference_r = np.real(ref)
self.reference_i = np.imag(ref)
def init_filters(self, frequency, bandwidth):
# convert bandwidth normalized to Nyquist interval
n_bandwidth = bandwidth * self.time_step * 2
n_frequency = abs(frequency) * self.time_step * 2
# arbitrarily decide on three stage filter pipeline
# 1. first stage decimating filter on real data
# 2. second stage decimating filter on mixed product to boost n_bandwidth
# 3. final channel selecting filter at n_bandwidth/2
# anecdotally don't decimate more than a factor of eight for stability
self.decim_factors = [1] * 3
self.filters = [None] * 3
# first stage decimating filter
# maximize first stage decimation:
# * minimize subsequent stages time taken
# * filter and decimate while signal is still real
# * first stage decimation cannot be too large or then 2omega signal from mixing will alias
self.d1 = 1
while (self.d1 < 8) and (2 * n_frequency <= 0.8 / self.d1) and (
self.d1 < self.decimation_factor.value):
self.d1 *= 2
n_bandwidth *= 2
n_frequency *= 2
if self.d1 > 1:
# create an anti-aliasing filter
# pass-band to 0.8 * decimation factor; anecdotally single precision needs order <= 4 for stability
b, a = scipy.signal.cheby1(4, 3, 0.8 / self.d1)
b = np.float32(b)
a = np.float32(a)
self.decim_factors[0] = self.d1
self.filters[0] = (b, a)
# store decimated reference for mix down
self.update_references(frequency)
# second stage filter to bring n_bandwidth/2 up
# decimation cannot be too large or will impinge on channel bandwidth (keep n_bandwidth/2 <= 0.8)
self.d2 = 1
while (self.d2 < 8) and (
(self.d1 * self.d2) <
self.decimation_factor.value) and (n_bandwidth / 2 <= 0.8):
self.d2 *= 2
n_bandwidth *= 2
n_frequency *= 2
if self.d2 > 1:
# create an anti-aliasing filter
# pass-band to 0.8 * decimation factor; anecdotally single precision needs order <= 4 for stability
b, a = scipy.signal.cheby1(4, 3, 0.8 / self.d2)
b = np.float32(b)
a = np.float32(a)
self.decim_factors[1] = self.d2
self.filters[1] = (b, a)
# final channel selection filter
if n_bandwidth < 0.1:
raise ValueError(
"Insufficient decimation to achieve stable filter: {}.".format(
n_bandwidth))
b, a = scipy.signal.cheby1(4, 3, n_bandwidth / 2)
b = np.float32(b)
a = np.float32(a)
self.decim_factors[2] = self.decimation_factor.value // (self.d1 *
self.d2)
self.filters[2] = (b, a)
def update_descriptors(self):
logger.debug(
'Updating Channelizer "%s" descriptors based on input descriptor: %s.',
self.name, self.sink.descriptor)
# extract record time sampling
self.time_pts = self.sink.descriptor.axes[-1].points
self.record_length = len(self.time_pts)
self.time_step = self.time_pts[1] - self.time_pts[0]
logger.debug("Channelizer time_step = {}".format(self.time_step))
# We will be decimating along a time axis, which is always
# going to be the last axis given the way we usually take data.
# TODO: perform this function along a named axis rather than a numbered axis
# in case something about this changes.
# update output descriptors
decimated_descriptor = DataStreamDescriptor()
decimated_descriptor.axes = self.sink.descriptor.axes[:]
decimated_descriptor.axes[-1] = deepcopy(self.sink.descriptor.axes[-1])
decimated_descriptor.axes[-1].points = self.sink.descriptor.axes[
-1].points[self.decimation_factor.value -
1::self.decimation_factor.value]
decimated_descriptor.axes[
-1].original_points = decimated_descriptor.axes[-1].points
decimated_descriptor._exp_src = self.sink.descriptor._exp_src
decimated_descriptor.dtype = np.complex64
self.output_descriptor = decimated_descriptor
for os in self.source.output_streams:
os.set_descriptor(decimated_descriptor)
if os.end_connector is not None:
os.end_connector.update_descriptors()
async def process_data(self, data):
# Append any data carried from the last run
if self.carry.size > 0:
data = np.concatenate((self.carry, data))
# This is the largest number of records we can handle
num_records = data.size // self.record_length
# This is the carryover that we'll store until next round.
# If nothing is left then reset the carryover.
remaining_points = data.size % self.record_length
if remaining_points > 0:
if num_records > 0:
self.carry = data[-remaining_points:]
data = data[:-remaining_points]
else:
self.carry = data
else:
self.carry = np.zeros(0, dtype=self.output_descriptor.dtype)
if num_records > 0:
# The records are processed in parallel after being reshaped here
reshaped_data = np.reshape(data, (num_records, self.record_length),
order="C")
# Update demodulation frequency if necessary
if self.follow_axis.value is not "":
freq = self.demod_freqs[(self.idx % self.pts_before_freq_reset)
// self.pts_before_freq_update]
if freq != self.current_freq:
self.update_references(freq)
self.current_freq = freq
self.idx += data.size
# first stage decimating filter
if self.filters[0] is None:
filtered = reshaped_data
else:
stacked_coeffs = np.concatenate(self.filters[0])
# filter
if np.iscomplexobj(reshaped_data):
# TODO: compile complex versions of the IPP functions
filtered_r = np.empty_like(reshaped_data, dtype=np.float32)
filtered_i = np.empty_like(reshaped_data, dtype=np.float32)
libipp.filter_records_iir(
stacked_coeffs, self.filters[0][0].size - 1,
np.ascontiguousarray(
reshaped_data.real.astype(np.float32)),
self.record_length, num_records, filtered_r)
libipp.filter_records_iir(
stacked_coeffs, self.filters[0][0].size - 1,
np.ascontiguousarray(
reshaped_data.imag.astype(np.float32)),
self.record_length, num_records, filtered_i)
filtered = filtered_r + 1j * filtered_i
# decimate
if self.decim_factors[0] > 1:
filtered = filtered[:, ::self.decim_factors[0]]
else:
filtered = np.empty_like(reshaped_data)
libipp.filter_records_iir(stacked_coeffs,
self.filters[0][0].size - 1,
reshaped_data,
self.record_length, num_records,
filtered)
# decimate
if self.decim_factors[0] > 1:
filtered = filtered[:, ::self.decim_factors[0]]
# mix with reference
# keep real and imaginary separate for filtering below
if np.iscomplexobj(reshaped_data):
filtered *= self.reference
filtered_r = filtered.real
filtered_i = filtered.imag
else:
filtered_r = self.reference_r * filtered
filtered_i = self.reference_i * filtered
# channel selection filters
for ct in [1, 2]:
if self.filters[ct] == None:
continue
coeffs = self.filters[ct]
stacked_coeffs = np.concatenate(self.filters[ct])
out_r = np.empty_like(filtered_r).astype(np.float32)
out_i = np.empty_like(filtered_i).astype(np.float32)
libipp.filter_records_iir(
stacked_coeffs, self.filters[ct][0].size - 1,
np.ascontiguousarray(filtered_r.astype(np.float32)),
filtered_r.shape[-1], num_records, out_r)
libipp.filter_records_iir(
stacked_coeffs, self.filters[ct][0].size - 1,
np.ascontiguousarray(filtered_i.astype(np.float32)),
filtered_i.shape[-1], num_records, out_i)
# decimate
if self.decim_factors[ct] > 1:
filtered_r = np.copy(out_r[:, ::self.decim_factors[ct]],
order="C")
filtered_i = np.copy(out_i[:, ::self.decim_factors[ct]],
order="C")
else:
filtered_r = out_r
filtered_i = out_i
filtered = filtered_r + 1j * filtered_i
# recover gain from selecting single sideband
filtered *= 2
# push to ouptut connectors
for os in self.source.output_streams:
await os.push(filtered)
