178 lines
6.5 KiB
Python
178 lines
6.5 KiB
Python
# -*- coding: iso-8859-1 -*-
|
|
|
|
TXEnableDelay = 2e-6
|
|
TXEnableValue = 0b0001 # TTL line blanking RF amplifier (bit 0)
|
|
TXPulseValue = 0b0010 # TTL line triggering RF pulses (bit 1)
|
|
ADCSensitivity = 2 # voltage span for ADC
|
|
|
|
def experiment(): # saturation-recovery with soild-echo detection
|
|
|
|
# set up acquisition parameters:
|
|
pars = {}
|
|
pars['P90'] = 2.3e-6 # 90-degree pulse length (s)
|
|
pars['SF'] = 46.7e6 # spectrometer frequency (Hz)
|
|
pars['O1'] = 5.6e3 # offset from SF (Hz)
|
|
pars['SW'] = 10e6 # spectral window (Hz)
|
|
pars['SI'] = 1*1024 # number of acquisition points
|
|
pars['NS'] = 16 # number of scans
|
|
pars['DS'] = 0 # number of dummy scans
|
|
pars['TAU'] = 1 # delay for recovery (s)
|
|
pars['D3'] = 20e-6 # echo delay (s)
|
|
pars['D4'] = 0 # echo pre-aquisition delay (s)
|
|
pars['PHA'] = -30 # receiver phase (degree)
|
|
# -*- these ain't variable: -*-
|
|
pars['NECH'] = 40 # number of saturation pulses
|
|
pars['D1'] = 100e-3 # starting interval in saturation sequence (s)
|
|
pars['D2'] = 1e-4 # end interval in saturation sequence (s)
|
|
pars['DATADIR'] = '/home/fprak/Students/' # data directory
|
|
pars['OUTFILE'] = None # output file name
|
|
|
|
# specify a variable parameter (optional):
|
|
pars['VAR_PAR'] = 'TAU' # variable parameter name (a string)
|
|
start = 1e-4 # starting value
|
|
stop = 1e-0 # end value
|
|
steps = 10 # number of values
|
|
log_scale = True # log scale flag
|
|
stag_range = True # staggered range flag
|
|
|
|
# check parameters for safety:
|
|
if pars['PHA'] < 0:
|
|
pars['PHA'] = 360 + pars['PHA']
|
|
|
|
if pars['P90'] > 20e-6:
|
|
raise Exception("pulse too long!!!")
|
|
|
|
# check whether a variable parameter is named:
|
|
var_key = pars.get('VAR_PAR')
|
|
if var_key == 'P90' and (start > 20e-6 or stop > 20e-6):
|
|
raise Exception("Pulse too long!!!")
|
|
|
|
if pars['NS']%8 != 0:
|
|
pars['NS'] = int(round(pars['NS'] / 8) + 1) * 8
|
|
print 'Number of scans changed to ',pars['NS'],' due to phase cycling'
|
|
|
|
if pars['D1'] < pars['D2']:
|
|
raise Exception("D1 must be greater than D2!")
|
|
|
|
sat_length = sum(log_range(pars['D1'],pars['D2'],pars['NECH']))
|
|
if sat_length > 1.:
|
|
raise Exception("saturation sequence too long!!!")
|
|
|
|
# start the experiment:
|
|
if var_key:
|
|
# this is an arrayed experiment:
|
|
if log_scale:
|
|
array = log_range(start, stop, steps)
|
|
else:
|
|
array = lin_range(start, stop, steps)
|
|
|
|
if stag_range:
|
|
array = staggered_range(array, size = 2)
|
|
|
|
# estimate the experiment time:
|
|
if var_key == 'TAU':
|
|
seconds = ((sat_length + pars['D3']*2) * steps + sum(array)) * (pars['NS'] + pars['DS'])
|
|
elif var_key == 'D3':
|
|
seconds = ((sat_length + pars['TAU']) * steps + sum(array)*2) * (pars['NS'] + pars['DS'])
|
|
else:
|
|
seconds = (sat_length + pars['TAU'] + pars['D3']*2) * steps * (pars['NS']+ pars['DS'])
|
|
m, s = divmod(seconds, 60)
|
|
h, m = divmod(m, 60)
|
|
print '%s%02d:%02d:%02d' % ('Experiment time estimated: ', h, m, s)
|
|
|
|
# loop for a variable parameter:
|
|
for index, pars[var_key] in enumerate(array):
|
|
print 'Arrayed experiment for '+var_key+': run = '+str(index+1)+\
|
|
' out of '+str(array.size)+': value = '+str(pars[var_key])
|
|
# loop for accumulation:
|
|
for run in xrange(pars['NS']+pars['DS']):
|
|
yield satrec2_experiment(pars, run)
|
|
synchronize()
|
|
else:
|
|
# estimate the experiment time:
|
|
seconds = (sat_length + pars['TAU'] + pars['D3']*2) * (pars['NS']+ pars['DS'])
|
|
m, s = divmod(seconds, 60)
|
|
h, m = divmod(m, 60)
|
|
print '%s%02d:%02d:%02d' % ('Experiment time estimated: ', h, m, s)
|
|
|
|
# loop for accumulation:
|
|
for run in xrange(pars['NS']+pars['DS']):
|
|
yield satrec2_experiment(pars, run)
|
|
|
|
|
|
# the pulse program:
|
|
|
|
def satrec2_experiment(pars, run):
|
|
e=Experiment()
|
|
|
|
dummy_scans = pars.get('DS')
|
|
if dummy_scans:
|
|
run -= dummy_scans
|
|
|
|
pars['PROG'] = 'satrec2_experiment'
|
|
|
|
# phase lists:
|
|
pars['PH1'] = [ 0] # saturation pulses
|
|
pars['PH3'] = [ 0, 180, 0, 180, 90, 270, 90, 270] # 1st 90-degree pulse
|
|
pars['PH4'] = [90, 90, 270, 270, 0, 0, 180, 180] # 2nd 90-degree pulse
|
|
pars['PH2'] = [ 0, 180, 0, 180, 90, 270, 90, 270] # receiver
|
|
|
|
# read in variables:
|
|
P90 = pars['P90']
|
|
SF = pars['SF']
|
|
O1 = pars['O1']
|
|
NECH = pars['NECH']
|
|
D1 = pars['D1']
|
|
D2 = pars['D2']
|
|
D3 = pars['D3']
|
|
D4 = pars['D4']
|
|
TAU = pars['TAU']
|
|
PH1 = pars['PH1'][run%len(pars['PH1'])]
|
|
PH3 = pars['PH3'][run%len(pars['PH3'])]
|
|
PH4 = pars['PH4'][run%len(pars['PH4'])]
|
|
PH2 = pars['PH2'][run%len(pars['PH2'])]
|
|
PHA = pars['PHA']
|
|
|
|
# set variable delay list for saturation pulses:
|
|
vdlist = log_range(D2, D1, NECH-1)
|
|
|
|
# set sampling parameters:
|
|
SI = pars['SI']
|
|
SW = pars['SW']
|
|
while SW <= 10e6 and SI < 256*1024:
|
|
SI *= 2
|
|
SW *= 2
|
|
|
|
# the pulse sequence:
|
|
|
|
# saturation:
|
|
e.set_frequency(SF+O1, phase=PH1) # set frequency and phase for saturation pulses
|
|
e.ttl_pulse(TXEnableDelay, value=TXEnableValue) # enable RF amplifier
|
|
e.ttl_pulse(P90, value=TXEnableValue|TXPulseValue) # apply 90-degree pulse
|
|
for delay in vdlist[::-1]:
|
|
e.wait(delay-P90-TXEnableDelay) # wait for next saturation pulse
|
|
e.ttl_pulse(TXEnableDelay, value=TXEnableValue) # enable RF amplifier
|
|
e.ttl_pulse(P90, value=TXEnableValue|TXPulseValue) # apply 90-degree pulse
|
|
|
|
# recovery:
|
|
e.wait(TAU) # wait for tau
|
|
e.set_phase(PH3) # set phase for next pulse
|
|
|
|
# echo detection:
|
|
e.ttl_pulse(TXEnableDelay, value=TXEnableValue) # enable RF amplifier
|
|
e.ttl_pulse(P90, value=TXEnableValue|TXPulseValue) # apply 90-degree pulse
|
|
e.wait(D3-P90-TXEnableDelay) # echo delay
|
|
e.set_phase(PH4) # set phase for next pulse
|
|
e.ttl_pulse(TXEnableDelay, value=TXEnableValue) # enable RF amplifier
|
|
e.ttl_pulse(P90, value=TXEnableValue|TXPulseValue) # apply 90-degree pulse
|
|
e.set_phase(PHA) # set phase for receiver
|
|
e.wait(D3-P90/2+D4) # echo delay
|
|
e.record(SI, SW, sensitivity=ADCSensitivity) # acquisition
|
|
|
|
# write experiment attributes:
|
|
for key in pars.keys():
|
|
e.set_description(key, pars[key]) # pulse sequence parameters
|
|
e.set_description('run', run) # current scan
|
|
e.set_description('rec_phase', -PH2) # current receiver phase
|
|
|
|
return e |