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Commit 89931e18 authored by Jameson Rollins's avatar Jameson Rollins
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Merge branch 'QN2mode_nice' into 'master' 

modified quantum to ready for QN2mode

See merge request !22
parents 4c7dd4bd ec39a803
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1 merge request!22modified quantum to ready for QN2mode
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......@@ -9,6 +9,7 @@ __pycache__/
#vim temporaries
.*.swp
.*.swo
.#*
# Backups
*~
......
gwinc/noise/quantum.py
+ 76
− 61
View file @ 89931e18
......@@ -3,15 +3,26 @@ from numpy import pi, sqrt, arctan, sin, cos, exp, size, ones, zeros, log10, con
import numpy as np
import scipy.constants
import logging
from ..struct import Struct
def shotrad(f, ifo):
"""Quantum noise
corresponding author: mevans
modifications for resonant delay lines: Stefan Ballmer
"""
try:
sqzType = ifo.Squeezer.Type
except AttributeError:
sqzType = None
#if sqzType == '2mode':
# from .quantum_2mode import shotrad as shotrad_2mode
# return shotrad_2mode(f, ifo)
# deal with multiple bounces, required for resonant delay lines
# Stefan Ballmer 2012
if 'NFolded' in ifo.Infrastructure:
......@@ -19,7 +30,7 @@ def shotrad(f, ifo):
ifo.Materials.MirrorMass=ifo.Materials.MirrorMass/ifo.Infrastructure.NFolded**2
else:
NN=ifo.Infrastructure.NFolded
Ndispl=2*NN-1
Ndispl=2 * NN-1
ifo.Materials.MirrorMass=ifo.Materials.MirrorMass/Ndispl**2
#####################################################
......@@ -43,7 +54,7 @@ def shotrad(f, ifo):
logging.debug(Mn.shape)
logging.debug(Nfield, Nfreq)
raise Exception('Inconsistent matrix sizes returned by %s' % str(fname))
# deal with non-standard number of fields
if Nfield != 2:
if Nfield == 4:
......@@ -55,14 +66,36 @@ def shotrad(f, ifo):
#####################################################
# Input Squeezing
#####################################################
# ------------------------------------------- equation 63 BnC PRD 2004
#>>>>>>>> QUANTUM NOISE POWER SPECTRAL DENSITY WITH SQZ [BnC PRD 2004, 62]
#<<<<<<<<<<<<<<<<< Modified to include losses (KM)
#<<<<<<<<<<<<<<<<< Modified to include frequency dependent squeezing angle (LB)
# useful numbers
eta = ifo.Optics.Quadrature.dc # Homodyne Readout phase
#TODO, adjust Struct to allow deep defaulted access
# Homodyne Readout phase
eta_orig = ifo.Optics.get('Quadrature', Struct()).get('dc', None)
ifoRead = ifo.get('Squeezer', Struct()).get('Readout', None)
if ifoRead is None:
eta = eta_orig
if eta_orig is None:
raise Exception("must add Quadrature.dc or Readout...")
elif ifoRead.type == 'DC':
eta = np.sign(ifoRead.fringe_side) * np.arccos((ifoRead.defect_PWR_W / ifoRead.readout_PWR_W)**.5)
elif ifoRead.type == 'homodyne':
eta = ifoRead.homodyne_eta # Homodyne Readout phase
else:
raise Exception("Unknown Readout Type" % Nfield)
if eta_orig is not None:
logging.warn((
'Quadrature.dc is redundant with '
'Squeezer.Readout and is deprecated.'
))
if eta_orig != eta:
raise Exception("Quadrature.dc inconsistent with Readout eta")
lambda_PD = 1 - ifo.Optics.PhotoDetectorEfficiency # PD losses
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
......@@ -72,7 +105,7 @@ def shotrad(f, ifo):
sqzType = 'None'
else:
sqzType = ifo.Squeezer.get('Type', 'Freq Independent')
# extract common parameters
if sqzType == 'None':
SQZ_DB = 0 # Squeeing in dB
......@@ -83,10 +116,10 @@ def shotrad(f, ifo):
else:
SQZ_DB = ifo.Squeezer.AmplitudedB # Squeeing in dB
lambda_in = ifo.Squeezer.InjectionLoss # Loss to squeezing before injection [Power]
alpha = ifo.Squeezer.SQZAngle # Freq Indep Squeeze angle
ANTISQZ_DB = ifo.Squeezer.get('AntiAmplitudedB', SQZ_DB) # Anti squeezing in db
etaRMS = ifo.Squeezer.get('LOAngleRMS', 0) # quadrature noise
alpha = ifo.Squeezer.SQZAngle # Freq Indep Squeeze angle
ANTISQZ_DB = ifo.Squeezer.get('AntiAmplitudedB', SQZ_DB) # Anti squeezing in db
etaRMS = ifo.Squeezer.get('LOAngleRMS', 0) # quadrature noise
# switch on squeezing type for other input squeezing modifications
if sqzType == 'None':
pass
......@@ -97,33 +130,33 @@ def shotrad(f, ifo):
elif sqzType == 'Optimal':
# compute optimal squeezing angle
alpha = sqzOptimalSqueezeAngle(Mifo, eta)
logging.debug('You are injecting %g dB of squeezing with optimal frequency dependent squeezing angle' % SQZ_DB)
elif sqzType == 'OptimalOptimal':
# compute optimal squeezing angle, assuming optimal readout phase
R = SQZ_DB / (20 * log10(exp(1)))
MnPD = sqzInjectionLoss(Mn, lambda_PD)
MsigPD = Msig * sqrt(1 - lambda_PD)
alpha = sqzOptimalSqueezeAngle(Mifo, [], [R, lambda_in], MsigPD, MnPD)
logging.debug('You are injecting %g dB of squeezing with optimal FD squeezing angle, for optimal readout phase' % SQZ_DB)
elif sqzType == 'Freq Dependent':
logging.debug('You are injecting %g dB of squeezing with frequency dependent squeezing angle' % SQZ_DB)
else:
raise Exception('ifo.Squeezer.Type must be None, Freq Independent, Optimal, or Frequency Dependent, not "%s"' % sqzType)
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# Define input matrix of Squeezing
R = SQZ_DB / (20 * log10(exp(1))) # Squeeze factor
R_anti = ANTISQZ_DB / (20 * log10(exp(1))) # Squeeze factor
R = SQZ_DB / (20 * log10(exp(1))) # Squeeze factor
R_anti = ANTISQZ_DB / (20 * log10(exp(1))) # Squeeze factor
Msqz = np.array([[exp(-R), 0], [0, exp(R_anti)]])
# expand to Nfreq
Msqz = np.transpose(np.tile(Msqz, (Nfreq,1,1)), axes=(1,2,0))
# add input rotation
MsqzRot = make2x2TF(cos(alpha), -sin(alpha), sin(alpha), cos(alpha))
Msqz = getProdTF(MsqzRot, Msqz)
......@@ -132,7 +165,7 @@ def shotrad(f, ifo):
# if strcmp(sqzType, 'Optimal') || strcmp(sqzType, 'OptimalOptimal')
# Msqz = [exp(-R) 0; 0 exp(-R)];
# end
# Include losses (lambda_in=ifo.Squeezer.InjectionLoss)
Msqz = sqzInjectionLoss(Msqz, lambda_in)
......@@ -141,7 +174,7 @@ def shotrad(f, ifo):
if sqzType == 'Freq Dependent' and 'FilterCavity' in ifo.Squeezer:
logging.debug(' Applying %d input filter cavities' % np.atleast_1d(ifo.Squeezer.FilterCavity).size)
Mr, Msqz = sqzFilterCavityChain(f, np.atleast_1d(ifo.Squeezer.FilterCavity), Msqz)
#####################################################
# IFO Transfer and Output Filter Cavities
#####################################################
......@@ -167,11 +200,12 @@ def shotrad(f, ifo):
Msig = getProdTF(Mr, Msig)
# Mnoise = getProdTF(Mn, Mnoise);
elif ifo.OutputFilter.Type == 'Optimal':
elif ifo.OutputFilter.Type == 'Optimal':
logging.debug(' Optimal output filtering!')
# compute optimal angle, including upcoming PD losses
MnPD = sqzInjectionLoss(Mnoise, lambda_PD)
raise NotImplementedError("Cannot do optimal phase yet")
zeta = sqzOptimalReadoutPhase(Msig, MnPD)
# rotate by that angle, less the homodyne angle
......@@ -184,8 +218,8 @@ def shotrad(f, ifo):
else:
raise Exception('ifo.OutputFilter.Type must be None, Chain or Optimal, not "%s"' % ifo.OutputFilter.Type)
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# add PD efficiency
Mnoise = sqzInjectionLoss(Mnoise, lambda_PD)
Msig = Msig * sqrt(1 - lambda_PD)
......@@ -224,18 +258,18 @@ def shotradSignalRecycled(f, ifo):
"""Quantum noise model for signal recycled IFO
See shotrad for more info.
All references to Buonanno & Chen PRD 64 042006 (2001) (hereafter BnC)
Updated to include losses DEC 2006 Kirk McKenzie using BnC notation
Updated to include squeezing April 2009 KM
Updated April 2010 KM, LB
moved out of shotrad May 2010, mevans
output is used in shotrad to compute final noise as
n = coeff * (vHD * Msqz * Msqz' * vHD') / (vHD * Md * Md' * vHD')
where
Msqz = [Mc MsqueezeInput, Mn]
coeff = frequency dependent overall noise coefficient (Nx1)
Mifo = IFO input-output relation for the AS port
Msig = signal transfer to the AS port
......@@ -363,39 +397,20 @@ def shotradSignalRecycled(f, ifo):
def make2x2TF(A11, A12, A21, A22):
"""Create transfer matrix with 2x2xnF
The vectors must all have nF elements.
"""
nF = max([size(A11), size(A12), size(A21), size(A22)])
# if any input is just a number, expand it
if size(A11) == 1:
A11 = A11 * ones(nF)
if size(A12) == 1:
A12 = A12 * ones(nF)
if size(A21) == 1:
A21 = A21 * ones(nF)
if size(A22) == 1:
A22 = A22 * ones(nF)
# check to be sure that they all match now
if any(np.array([size(A11), size(A12), size(A21), size(A22)]) != nF):
raise Exception('Input vector length mismatch.')
# build output matrix
M3 = zeros((2,2,nF), dtype=complex)
for k in range(nF):
M3[:,:,k] = np.array([[A11[k], A12[k]], [A21[k], A22[k]]])
return M3
Create transfer matrix with 2x2xnF.
"""
#now using numpy with broadcasting
A11, A12, A21, A22 = np.broadcast_arrays(A11, A12, A21, A22)
M3 = np.array([[A11, A12], [A21, A22]])
return M3.reshape(2, 2, -1)
def getProdTF(lhs, rhs):
"""Compute the product of M Nout x Nin x Naf frequency dependent transfer matrices
See also getTF.
NOTE: To perform more complicated operations on transfer
matrices, see LTI object FRD ("help frd"). This
function is the same as: freqresp(frd(lhs) * frd(rhs), f)
......@@ -446,7 +461,7 @@ def sqzFilterCavityChain(f, params, Mn):
"""Transfer relation for a chain of filter cavities
Noise added by cavity losses are also output.
f = frequency vector [Hz]
param.fdetune = detuning [Hz]
param.L = cavity length
......@@ -455,17 +470,17 @@ def sqzFilterCavityChain(f, params, Mn):
param.Te = end mirror trasmission
param.Le = end mirror loss
param.Rot = phase rotation after cavity
Mn0 = input noise
Mc = input to output transfer
Mn = filtered input noise, plus noise due to cavity losses
Note:
[Mc, Mn] = sqzFilterCavityChain(f, params, Mn0)
is the same as
[Mc, Mn] = sqzFilterCavityChain(f, params);
Mn = [getProdTF(Mc, Mn0), Mn];
corresponding author: mevans
"""
......@@ -516,11 +531,11 @@ def sqzFilterCavity(f, Lcav, Ti, Te, Lrt, fdetune, MinR, MinT=1):
so no noise field is added to Mnoise. If no argument is given, or
the scalar 1 is given, an Mr unsqueezed input is assumed and Mr is
concatenated into Mnoise.
MinT: squeezed field injected from the back of the filter cavity
MinT: squeezed field injected from the back of the filter cavity
with MinR, this argument can be omitted or set to 1 to indicate
and unsqueezed input. [] can be used to avoid adding a noise
term to Mnoise.
corresponding authors: LisaB, mevans
"""
......@@ -590,14 +605,14 @@ def sqzFilterCavity(f, Lcav, Ti, Te, Lrt, fdetune, MinR, MinT=1):
Mnoise = Mr * MinR
else:
Mnoise = getProdTF(Mr, MinR)
# transmitted fields
if MinT != [] and Te > 0:
if np.isscalar(MinT) and MinT == 1:
Mnoise = np.hstack((Mnoise, Mt))
else:
Mnoise = np.hstack((Mnoise, getProdTF(Mt, MinT)))
# loss fields
if Lrt > 0:
Mnoise = np.hstack((Mnoise, Ml))
......
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