% % C1lentickle1.m % % * OLT % * PM coupling % * AM coupling % * Seismic noise % Feb 2012 KK % % setupLentickle; %% Run the lentickle engine % interferometer model opt = optC1(paramC1DRMI); % create the opt object opt = probesC1_00(opt, paramC1DRMI); % control model cucumber = C1cucumber(opt); % create the cucumber structure % look at exampleMICHcucumber.m for % more info about the cucumber. % frequency vector fHigh = 10000; fLow = 0.5; f = logspace(log10(fLow),log10(fHigh),500).'; % choose the frequency array we will use % get the closed loop results results = lentickleEngine(cucumber,[],f); % calculate all results %% Transfer functions % All the transfer functions (which include closed loops and all cross % coupling effects) can be extracted from the results structure, and the % pickleTF function makes that easy. %% Open Loop Gains % We will calculate the open loop gains of our two degrees of freedom, the % differential and common modes of the arms, 'DIFF' and 'COMM'. pickleTF % will easily give us the closed loop gain, and calulating the open loop % gain from that is fairly easy. (OLG = 1 - 1./CLG) MICHOLG = 1 - 1./pickleTF(results,'MICH','MICH'); PRCLOLG = 1 - 1./pickleTF(results,'PRCL','PRCL'); SRCLOLG = 1 - 1./pickleTF(results,'SRCL','SRCL'); % make a plot of them figure(1) subplot(2,1,1) loglog(f,abs(MICHOLG),'r',f,abs(PRCLOLG),'b',f,abs(SRCLOLG),'--g','Linewidth',2); title('Open Loop Gain') ylabel('Magnitude') legend('MICH','PRCL','SRCL') xlim([fLow fHigh]) grid on subplot(2,1,2) semilogx(f,180/pi*angle(MICHOLG),'r',f,180/pi*angle(PRCLOLG),'b',f,180/pi*angle(SRCLOLG),'--g','Linewidth',2); ylabel('Phase (degrees)') xlabel('Frequency (Hz)') xlim([fLow fHigh]) grid on %% Noise Transfer Functions % Here we will calculate the transfer function of laser noises to our % length sensors, we will calibrate the sensor in terms of meters of the % relevant degree of freedom. %% Calibrations % First we will calculate the calibration of AS_Q in DIFF meters, and % REFL_I in COMM meters. % ASQ2 MICH ASQ2_MICH_calmeters = pickleTF(results,'IX','MICH') - pickleTF(results,'IY','MICH'); % units of [AS_Q counts]/m % REFL_3I1 PARCL REFL3I1_P_calmeters = pickleTF(results,'PR','PRCL') ; % units of [REFL_I counts]/m % AS3Q2 SRCL AS3Q2_S_calmeters = pickleTF(results, 'SR', 'SRCL'); %% PM noise coupling % Now we will calculate the coulping of laser frequency noise to AS_Q and % REFL_I. The PM 'mirror' is the phase modulator actuator, we divide by % i*f to get frequency. FMtoASQ2 = pickleTF(results,'PM','AS_Q2') ./ ( 1i * f ); % units of [AS_Q counts]/Hz FMtoREFL3I1 = pickleTF(results,'PM','REFL_3I1') ./ ( 1i * f ); % units of [REFL_I counts]/Hz FMtoAS3Q2 = pickleTF(results,'PM','AS_3Q2') ./ (1i *f); % Now we calibrate in terms of meters. FMtoMICH = FMtoASQ2 ./ ASQ2_MICH_calmeters; % units of m/Hz FMtoPRCL = FMtoREFL3I1 ./ REFL3I1_P_calmeters; % units of m/Hz FMtoSRCL = FMtoAS3Q2 ./ AS3Q2_S_calmeters; % plots figure(2) subplot(2,1,1) loglog(f,abs(FMtoMICH),'r',f,abs(FMtoPRCL),'b',f,abs(FMtoSRCL),'g','Linewidth',2); title('Frequency Noise Coupling') ylabel('Magnitude (m/Hz)') legend('MICH (ASQ2)','PRCL(REFL3I1)','SRCL(AS3Q2)') xlim([fLow fHigh]) grid on subplot(2,1,2) semilogx(f,180/pi*angle(FMtoMICH),'r',f,180/pi*angle(FMtoPRCL),'b',f,180/pi*angle(FMtoSRCL),'g','Linewidth',2); ylabel('Phase (degrees)') xlabel('Frequency (Hz)') xlim([fLow fHigh]) grid on %% AM Noise coupling % % Same manner as FM coupling % AMtoASQ2 = pickleTF(results,'AM','AS_Q2') ; % units of [AS_Q counts]/Hz AMtoREFL3I1 = pickleTF(results,'AM','REFL_3I1'); % units of [REFL_I counts]/Hz AMtoAS3Q2 = pickleTF(results,'AM','AS_3Q2'); AMtoMICH = AMtoASQ2 ./ ASQ2_MICH_calmeters; % units of m/Hz AMtoPRCL = AMtoREFL3I1 ./ REFL3I1_P_calmeters; % units of m/Hz AMtoSRCL = AMtoAS3Q2 ./ AS3Q2_S_calmeters; % plots figure(3) subplot(2,1,1) loglog(f,abs(AMtoMICH),'r',f,abs(AMtoPRCL),'b',f,abs(AMtoSRCL),'g','Linewidth',2); title('Amplitude Noise Coupling') ylabel('Magnitude (/Hz)') legend('MICH (ASQ2)','PRCL(REFL3I1)','SRCL(AS3Q2)') xlim([fLow fHigh]) grid on subplot(2,1,2) semilogx(f,180/pi*angle(AMtoMICH),'r',f,180/pi*angle(AMtoPRCL),'b',f,180/pi*angle(AMtoSRCL),'g','Linewidth',2); ylabel('Phase (degrees)') xlabel('Frequency (Hz)') xlim([fLow fHigh]) grid on %% Sesimic noise estimation S = load('seismic_gwinc.mat'); % gwinc data, m/rtHZ, ASD Sdata0 = interp1(S.seismic.darmseis_f, S.seismic.darmseis_x, f, 'cubic', NaN); Sdata = Sdata0; % MICH (ASQ2) SdataMICH = sqrt( (Sdata.*pickleTF(results, 'IX','MICH')).^2 ... + (Sdata.*pickleTF(results, 'IY','MICH')).^2 ... + (Sdata.*pickleTF(results, 'PR','MICH')).^2 ... + (Sdata.*pickleTF(results, 'SR','MICH')).^2 ); % m/rtHz * cts/m = cts/rtHz seis_calM = SdataMICH ./ ASQ2_MICH_calmeters; %cts/rtHz/(cts/m)=m/rtHz % PRCL (REFL3I1) SdataPRCL = sqrt( (Sdata.*pickleTF(results, 'IX','PRCL')).^2 ... + (Sdata.*pickleTF(results, 'IY','PRCL')).^2 ... + (Sdata.*pickleTF(results, 'PR','PRCL')).^2 ... + (Sdata.*pickleTF(results, 'SR','PRCL')).^2 ); % m/rtHz * cts/m = cts/rtHz seis_calP = SdataPRCL ./ REFL3I1_P_calmeters; %cts/rtHz/(cts/m)=m/rtHz % SRCL (AS3Q2) SdataSRCL = sqrt( (Sdata.*pickleTF(results, 'IX','SRCL')).^2 ... + (Sdata.*pickleTF(results, 'IY','SRCL')).^2 ... + (Sdata.*pickleTF(results, 'PR','SRCL')).^2 ... + (Sdata.*pickleTF(results, 'SR','SRCL')).^2 ); % m/rtHz * cts/m = cts/rtHz seis_calS = SdataSRCL ./ AS3Q2_S_calmeters; %cts/rtHz/(cts/m)=m/rtHz % plot figure(4) loglog(f,sqrt(4*abs(Sdata).^2),'k','Linewidth',2) hold on loglog(f,abs(seis_calM),'b',f,abs(seis_calP),'g--',f,abs(seis_calS),'m--','Linewidth',2)grid on title('Seismic noise level estimate') ylabel('ASD [m/rtHz]') xlabel('Frequency (Hz)') legend('raw data added for 4 optics','MICH calibrated','PRCL calibrated','SRCL calibrated') xlim([fLow fHigh]) %% Thermal noise budget