def test_down_conversion(args):
"""
@brief test to see if input signal of known frequency has been down converted
after mixing with known frequency
"""
output_steps = 2**args.freq_bits
# define the timestep for the 2 time series
dt_ddc = output_steps / args.clk
dt_data = 1. / args.clk
# read in the data from the ddc_bram and data_bram files
t_ddc, d_ddc = digital_utils.process_ddc_bram(args.ddc_file,
timestep=dt_ddc)
t_data, d_data = digital_utils.process_data_bram(args.data_file,
timestep=dt_data)
# get the power spectra of the signals
f_ddc, p_ddc = digital_utils.power(d_ddc, dt_ddc)
f_data, p_data = digital_utils.power(d_data, dt_data)
# plot the input signal on first subplot
pl.subplots_adjust(hspace=0.3)
pl.subplot(211)
pl.plot(f_data / 1e6, p_data)
# add the necessary info to the subplot
pl.figtext(0.2, 0.85, 'input tone at %.3f MHz' % (args.input_freq / 1e6))
pl.xlabel('frequency (MHz)', fontsize=16)
pl.ylabel('power', fontsize=16)
pl.xlim(-1.5 * args.input_freq / 1e6, 1.5 * args.input_freq / 1e6)
pl.subplot(212)
# determine the expected down-converted frequency, as mixer frequency - input freq
f_expected = abs(args.lof_int * args.clk / output_steps - args.input_freq)
# plot the down-converted spectra
pl.plot(f_ddc / 1e3, p_ddc)
pl.figtext(0.2, 0.4, 'mixed tone at %.3f kHz' % (f_expected / 1e3))
pl.xlabel('frequency (kHZ)', fontsize=16)
pl.ylabel('power', fontsize=16)
pl.xlim(-1.5 * f_expected / 1e3, 1.5 * f_expected / 1e3)
pl.show()
return
def test_down_conversion(args):
"""
@brief test to see if input signal of known frequency has been down converted
after mixing with known frequency
"""
output_steps = 2**args.freq_bits
# define the timestep for the 2 time series
dt_ddc = output_steps/args.clk
dt_data = 1./args.clk
# read in the data from the ddc_bram and data_bram files
t_ddc, d_ddc = digital_utils.process_ddc_bram(args.ddc_file, timestep=dt_ddc)
t_data, d_data = digital_utils.process_data_bram(args.data_file, timestep=dt_data)
# get the power spectra of the signals
f_ddc, p_ddc = digital_utils.power(d_ddc, dt_ddc)
f_data, p_data = digital_utils.power(d_data, dt_data)
# plot the input signal on first subplot
pl.subplots_adjust(hspace=0.3)
pl.subplot(211)
pl.plot(f_data/1e6, p_data)
# add the necessary info to the subplot
pl.figtext(0.2, 0.85, 'input tone at %.3f MHz' %(args.input_freq/1e6))
pl.xlabel('frequency (MHz)', fontsize=16)
pl.ylabel('power', fontsize=16)
pl.xlim(-1.5*args.input_freq/1e6, 1.5*args.input_freq/1e6)
pl.subplot(212)
# determine the expected down-converted frequency, as mixer frequency - input freq
f_expected = abs(args.lof_int * args.clk / output_steps - args.input_freq)
# plot the down-converted spectra
pl.plot(f_ddc/1e3, p_ddc)
pl.figtext(0.2, 0.4, 'mixed tone at %.3f kHz' %(f_expected/1e3))
pl.xlabel('frequency (kHZ)', fontsize=16)
pl.ylabel('power', fontsize=16)
pl.xlim(-1.5*f_expected/1e3, 1.5*f_expected/1e3)
pl.show()
return
def rcv(self, ns, trig):
"""
@brief receive the data from a UDP socket
@param ns: the shared Namespace between the two running Processes
(multiprocessing.Manager.Namespace)
@param trig: a trigger event to make sure we don't write/read shared array
at same time (multiprocessing.Event)
"""
# set up the socket as UDP
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
# always make sure we close the socket if program crashes
try:
# bind the socket to the input port
sock.bind(('0.0.0.0', self.port))
# loop continuously and receive data
while True:
# read in new data as long as the trig is not set
if not trig.is_set():
# receive the binary data through the socket
binary_data = sock.recv(self.max_recvd_bytes)
# process the binary data depending on if it is from a ddc_bram or data_bram file
if self.dtype == 'ddc':
times, newdata = digital_utils.process_ddc_bram(
None, timestep=self.dt, data=binary_data)
else:
times, newdata = digital_utils.process_data_bram(
None, timestep=self.dt, data=binary_data)
# concatenate these unseen samples together
ns.unseen_samples = np.concatenate(
(ns.unseen_samples, newdata))
except:
raise
finally:
sock.close()
def rcv(self, ns, trig):
"""
@brief receive the data from a UDP socket
@param ns: the shared Namespace between the two running Processes
(multiprocessing.Manager.Namespace)
@param trig: a trigger event to make sure we don't write/read shared array
at same time (multiprocessing.Event)
"""
# set up the socket as UDP
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
# always make sure we close the socket if program crashes
try:
# bind the socket to the input port
sock.bind( ('0.0.0.0', self.port) )
# loop continuously and receive data
while True:
# read in new data as long as the trig is not set
if not trig.is_set():
# receive the binary data through the socket
binary_data = sock.recv(self.max_recvd_bytes)
# process the binary data depending on if it is from a ddc_bram or data_bram file
if self.dtype == 'ddc':
times, newdata = digital_utils.process_ddc_bram(None, timestep=self.dt, data=binary_data)
else:
times, newdata = digital_utils.process_data_bram(None, timestep=self.dt, data=binary_data)
# concatenate these unseen samples together
ns.unseen_samples = np.concatenate( (ns.unseen_samples, newdata) )
except:
raise
finally:
sock.close()