--- a/system_settings/optic_input_example_lidar.py Fri Nov 24 22:54:15 2017 +0100
+++ b/system_settings/optic_input_example_lidar.py Thu Jan 24 21:24:25 2019 +0100
@@ -3,50 +3,49 @@
# which might improve the portability of the code within an executable.
# Due to problems I had with some two letter variables, most variables are now with at least
# three letters mixed small and capital.
-# To be used with lidar_correction_ghk.py ver. 0.9.5 and larger
-
-# Do you want to calculate the errors? If not, just the GHK-parameters are determined.
+# Error calculation?
+# False: only calculate the GHK-parameters. True: calculate also errors. Can take a long time.
Error_Calc = True
# Header to identify the lidar system
#
-EID = "xx" # Earlinet station ID
+EID = "xx" # Earlinet station ID
LID = "example lidar" # Additional lidar ID (short descriptive text)
print(" Lidar system :", EID, ", ", LID)
-# +++ IL Laser and +-Uncertainty
+# +++ IL Laser beam polarisation and +-Uncertainty
DOLP, dDOLP, nDOLP = 0.995, 0.005, 1 #degree of linear polarization; default 1
RotL, dRotL, nRotL = 0., 2., 1 #alpha; rotation of laser polarization in degrees; default 0
# +++ ME Emitter optics and +-Uncertainty; default = no emitter optics
-DiE, dDiE, nDiE = 0.0, 0.1, 0 # Diattenuation
-TiE = 1.0 # Unpolarized transmittance
-RetE, dRetE, nRetE = 0., 180., 0 # Retardance in degrees
-RotE, dRotE, nRotE = 0., 1.0, 0 # beta: Rotation of optical element in degrees
+DiE, dDiE, nDiE = 0.0, 0.1, 0 # Diattenuation; default 0
+TiE = 1.0 # Unpolarized transmittance; default 1
+RetE, dRetE, nRetE = 0., 180., 0 # Retardance in degrees; default 0
+RotE, dRotE, nRotE = 0., 1., 0 # beta: Rotation of optical element in degrees; default 0
# +++ MO Receiver optics including telescope
-DiO, dDiO, nDiO = 0.0, 0.1, 1 # Diattenuation
-TiO = 1.0 # Unpolarized transmittance
-RetO, dRetO, nRetO = 0., 180., 0 # Retardance in degrees
-RotO, dRotO, nRotO = 0., 0.5, 0 #gamma: Rotation of the optical element in degrees
+DiO, dDiO, nDiO = 0.0, 0.2, 1 # Diattenuation; default 0
+TiO = 1.0 # Unpolarized transmittance; default 1
+RetO, dRetO, nRetO = 0., 180., 0 # Retardance in degrees; default 0
+RotO, dRotO, nRotO = 0., 0.1, 0 #gamma: Rotation of the optical element in degrees; default 0
# +++++ PBS MT Transmitting path defined with TS, TP, PolFilter extinction ratio ERaT, and +-Uncertainty
# --- Polarizing beam splitter transmitting path
TP, dTP, nTP = 0.95, 0.01, 1 # transmittance of the PBS for parallel polarized light
-TS, dTS, nTS = 0.02, 0.01, 1 # transmittance of the PBS for cross polarized light
+TS, dTS, nTS = 0.005, 0.001, 1 # transmittance of the PBS for cross polarized light
RetT, dRetT, nRetT = 0.0, 180., 0 # Retardance in degrees
# --- Pol.Filter behind transmitted path of PBS
-ERaT, dERaT, nERaT = 0.001, 0.001, 1 # Extinction ratio
-RotaT, dRotaT, nRotaT = 0., 1., 1 # Rotation of the Pol.-filter in degrees; usually close to 0° because TP >> TS, but for PollyXTs it can also be close to 90°
+ERaT, dERaT, nERaT = 0.001, 0.001, 0 # Extinction ratio
+RotaT, dRotaT, nRotaT = 0., 1., 0 # Rotation of the Pol.-filter in degrees; usually close to 0° because TP >> TS, but for PollyXTs it can also be close to 90°
# --
-TiT = 0.5 * (TP + TS)
-DiT = (TP-TS)/(TP+TS)
-DaT = (1-ERaT)/(1+ERaT)
-TaT = 0.5*(1+ERaT)
+TiT = 0.5 * (TP + TS) # do not change this
+DiT = (TP-TS)/(TP+TS) # do not change this
+DaT = (1-ERaT)/(1+ERaT) # do not change this
+TaT = 0.5*(1+ERaT) # do not change this
-# +++++ PBS MR Reflecting path defined with RS, RP, PolFilter extinction ratio ERaR and +-Uncertainty
+# +++++ PBS MR Reflecting path defined with RS, RP, and cleaning PolFilter extinction ratio ERaR and +-Uncertainty
# ---- for PBS without absorption the change of RS and RP must depend on the change of TP and TS. Hence the values and uncertainties are not independent.
-RS_RP_depend_on_TS_TP = False
+RS_RP_depend_on_TS_TP = True
# --- Polarizing beam splitter reflecting path
if(RS_RP_depend_on_TS_TP):
RP, dRP, nRP = 1-TP, 0.00, 0 # do not change this
@@ -59,20 +58,26 @@
ERaR, dERaR, nERaR = 0.001, 0.001, 1 # Extinction ratio
RotaR, dRotaR, nRotaR = 90., 1., 1 # Rotation of the Pol.-filter in degrees; usually 90° because RS >> RP, but for PollyXTs it can also be 0°
# --
-TiR = 0.5 * (RP + RS)
-DiR = (RP-RS)/(RP+RS)
-DaR = (1-ERaR)/(1+ERaR)
-TaR = 0.5*(1+ERaR)
+TiR = 0.5 * (RP + RS) # do not change this
+DiR = (RP-RS)/(RP+RS) # do not change this
+DaR = (1-ERaR)/(1+ERaR) # do not change this
+TaR = 0.5*(1+ERaR) # do not change this
+# NEW --- Additional ND filter transmission (attenuation) during the calibration
+TCalT, dTCalT, nTCalT = 1, 0.01, 0 # transmitting path, default 1, 0, 0
+TCalR, dTCalR, nTCalR = 0.1, 0.001, 1 # reflecting path, default 1, 0, 0
-# +++ Orientation of the PBS with respect to the reference plane (see Polarisation-orientation.png and Polarisation-orientation-2.png in /system_settings)
-# Y = +1: polarisation in reference plane is transmitted,
-# Y = -1: polarisation in reference plane is reflected.
+# +++ Orientation of the PBS with respect to the reference plane (see Improvements_of_lidar_correction_ghk_ver.0.9.8_190124.pdf)
+# Y = +1: polarisation in reference plane is finally transmitted,
+# Y = -1: polarisation in reference plane is finally reflected.
Y = +1.
-# +++ Calibrator Location
-LocC = 3 #location of calibrator: 1 = behind laser; 2 = behind emitter; 3 = before receiver; 4 = before PBS
+# +++ Calibrator
+
# --- Calibrator Type used; defined by matrix values below
TypeC = 3 #Type of calibrator: 1 = mechanical rotator; 2 = hwp rotator (fixed retardation); 3 = linear polarizer; 4 = qwp; 5 = circular polarizer; 6 = real HWP calibration +-22.5°
+
+# --- Calibrator Location
+LocC = 3 #location of calibrator: 1 = behind laser; 2 = behind emitter; 3 = before receiver; 4 = before PBS
# --- MC Calibrator parameters
if TypeC == 1: #mechanical rotator
DiC, dDiC, nDiC = 0., 0., 0 # Diattenuation
@@ -81,7 +86,7 @@
RotC, dRotC, nRotC = 0., 0.1, 1 #constant calibrator rotation offset epsilon
# Rotation error without calibrator: if False, then epsilon = 0 for normal measurements
RotationErrorEpsilonForNormalMeasurements = True # is in general True for TypeC == 1 calibrator
-elif TypeC == 2: # HWP rotator without retardance!
+elif TypeC == 2: # HWP simulated by rotator without retardance!
DiC, dDiC, nDiC = 0., 0., 0 # Diattenuation; ideal 0.0
TiC = 1.
RetC, dRetC, nRetC = 180., 0., 0 # Retardance in degrees
@@ -89,9 +94,9 @@
RotC, dRotC, nRotC = 0.0, 0.1, 1 #constant calibrator rotation offset epsilon
RotationErrorEpsilonForNormalMeasurements = True # is in general True for TypeC == 2 calibrator
elif TypeC == 3: # linear polarizer calibrator. Diattenuation DiC = (1-ERC)/(1+ERC); ERC = extinction ratio of calibrator
- DiC, dDiC, nDiC = 0.9998, 0.0001, 1 # Diattenuation; ideal 1.0
+ DiC, dDiC, nDiC = 0.9998, 0.00019, 1 # Diattenuation; ideal 1.0
TiC = 0.4 # ideal 0.5
- RetC, dRetC, nRetC = 0., 0., 0 # Retardance in degrees
+ RetC, dRetC, nRetC = 0., 180., 3 # Retardance in degrees
RotC, dRotC, nRotC = 0.0, 0.1, 0 #constant calibrator rotation offset epsilon
RotationErrorEpsilonForNormalMeasurements = False # is in general False for TypeC == 3 calibrator
elif TypeC == 4: # QWP calibrator
@@ -112,10 +117,40 @@
sys.exit()
# --- LDRCal assumed atmospheric linear depolarization ratio during the calibration measurements in calibration range with almost clean air (first guess)
-LDRCal,dLDRCal,nLDRCal= 0.009, 0.005, 1 # spans the interference filter influence
+LDRCal,dLDRCal,nLDRCal= 0.2, 0.15, 1 # spans most of the atmospheric depolarisation variability
+# LDRCal,dLDRCal,nLDRCal= 0.009, 0.005, 1 # spans the interference filter influence
# ====================================================
# NOTE: there is no need to change anything below.
+# ====================================================
+# !!! don't change anything in this section !!!
+# NEW ***
+bPlotEtax = False # plot error histogramms for Etax
+
+# *** Only for signal noise errors ***
+nNCal = 0 # error nNCal, calibration signals: one-sigma in steps to left and right
+nNI = 0 # error nNI, 0° signals: one-sigma in steps to left and right; NI signals are calculated from NCalT and NCalR in main programm, but noise is assumed to be independent.
+
+# --- number of photon counts in the signal summed up in the calibration range during the calibration measurements
+NCalT = 28184 # default 1e6, assumed the same in +45° and -45° signals
+NCalR = 28184 # default 1e6, assumed the same in +45° and -45° signals
+NILfac = 2 # (relative duration (laser shots) of standard (0°) measurement to calibration measurements) * (range of std. meas. smoothing / calibration range); example: 100000#/5000# * 100/1000 = 2
+ # LDRmeas below will be used to calculate IR and IT of 0° signals.
+# calculate signal counts only from parallel 0° signal assuming the same electronic amplification in both channels; overwrites above values
+CalcFrom0deg = True
+NI = 1e5 #number of photon counts in the parallel 0°-signal
+
+if(CalcFrom0deg):
+ # either eFactT or eFacR is = 1 => rel. amplification
+ eFacT = 1 # rel. amplification of transmitted channel, approximate values are sufficient; def. = 1
+ eFacR = 10 # rel. amplification of reflected channel, approximate values are sufficient; def. = 1
+ NILfac = 2 # (relative duration (laser shots) of standard (0°) measurement to calibration measurements) * (range of std. meas. smoothing / calibration range); example: 100000#/5000# * 100/1000 = 2
+
+ NCalT = NI / NILfac * TCalT * eFacT # photon counts in transmitted signal during calibration
+ NCalR = NI / NILfac * TCalR * eFacR # photon counts in reflected signal during calibration
+ # LDRmeas below will be used to calculate IR and IT of 0° signals.
+# NEW *** End of signal noise error parameters ***
+
# --- LDRtrue for simulation of measurement => LDRsim
LDRtrue = 0.4
