def calc_vtec(dog,
rec_pos,
measurement,
ionh=IONOSPHERE_H,
el_cut=0.30,
n1=0,
n2=0,
rcvr_bias=0,
sat_bias=0):
"""
Given a receiver position and measurement from a specific sv
this calculates the vertical TEC, and the point at which
that TEC applies (between the sat and the rec)
"""
if measurement is None:
return None
stec = calc_tec(measurement,
n1=n1,
n2=n2,
rcvr_bias=rcvr_bias,
sat_bias=sat_bias)
if stec is None:
return None
if math.isnan(stec):
return None
if not measurement.processed:
measurement.process(dog)
el, az = helpers.get_el_az(rec_pos, measurement.sat_pos)
# ignore things too low in the sky
if el < el_cut or math.isnan(el):
return None
s_to_v = s_to_v_factor(el, ionh=ionh)
return stec * s_to_v, ion_loc(rec_pos, measurement.sat_pos), s_to_v
def filter_ticks(self, this_data):
'''
Starts with an assumed 'connection' of length zero at the first time point ('tick'). Runs through the list
of ticks (integers) in increasing order. Skips ticks where the satelite elevation was too low. With each tick,
judges whether the connection has 'dropped' either due to a) DISCONNECTION, or b) CYCLE_SLIP. If it has dropped,
it stops counting and the connection is considered 'complete' (i.e. initialized).
:param this_data:
:return:
'''
if self.ticks is not None:
return
self.ticks = []
last_seen = self.tick0
last_mw = None
for tick in range(self.tick0, self.tickn):
if not this_data[tick]:
continue
if not contains_needed_info(this_data[tick]):
continue
# ignore "bad connections" (low elevation)
if not this_data[tick].processed:
if not this_data[tick].process(self.dog):
continue
if not this_data[tick].corrected:
this_data[tick].correct(self.loc, self.dog)
el, _ = helpers.get_el_az(self.loc, this_data[tick].sat_pos)
if el < EL_CUTOFF:
continue
# detect slips due to long disconnection time
if tick - last_seen > DISCON_TIME:
# print("cycle slip: {0}-{1}@{2} exceeded discon time ({3})".format(
# self.station, self.prn, tick, last_seen
# ))
break
last_seen = tick
# detect cycle slips due to changing N_w
mw, _ = tec.melbourne_wubbena(this_data[tick])
if last_mw is not None and abs(last_mw - mw) > CYCLE_SLIP_CUTOFF:
print("cycle slip: {0}-{1}@{2} jump of {3:0.2f}".format(
self.station, self.prn, tick, last_mw - mw))
break
last_mw = mw
# all good
self.ticks.append(tick)
# Update the local property holding the first and last tick:
if self.ticks:
self.tick0 = self.ticks[0]
self.tickn = self.ticks[-1]
else:
self.ticks = [tick]
self.tick0 = tick
self.tickn = tick
def filter_ticks(self, this_data):
if self.ticks is not None:
return
self.ticks = []
last_seen = self.tick0
last_mw = None
for tick in range(self.tick0, self.tickn):
if not this_data[tick]:
continue
if not contains_needed_info(this_data[tick]):
continue
# ignore "bad connections" (low elevation)
if not this_data[tick].processed:
if not this_data[tick].process(self.dog):
continue
if not this_data[tick].corrected:
this_data[tick].correct(self.loc, self.dog)
el, _ = helpers.get_el_az(self.loc, this_data[tick].sat_pos)
if el < EL_CUTOFF:
continue
# detect slips due to long disconnection time
if tick - last_seen > DISCON_TIME:
# print("cycle slip: {0}-{1}@{2} exceeded discon time ({3})".format(
# self.station, self.prn, tick, last_seen
# ))
break
last_seen = tick
# detect cycle slips due to changing N_w
mw, _ = tec.melbourne_wubbena(this_data[tick])
if last_mw is not None and abs(last_mw - mw) > CYCLE_SLIP_CUTOFF:
print("cycle slip: {0}-{1}@{2} jump of {3:0.2f}".format(
self.station, self.prn, tick, last_mw - mw))
break
last_mw = mw
# all good
self.ticks.append(tick)
if self.ticks:
self.tick0 = self.ticks[0]
self.tickn = self.ticks[-1]
else:
self.ticks = [tick]
self.tick0 = tick
self.tickn = tick