Forums

I/Q samples with Matlab

Started by nov 1 month ago1 replylatest reply 1 month ago102 views

I collected Iridium (satcom) I/Q samples (5120 x 100000 complex double) and I would like to plot the range-Doppler response map by using the matlab tool (https://www.mathworks.com/help/phased/ref/phased.rangedopplerscope-system-object.html)

scope = phased.RangeDopplerScope( ... 'IQDataInput',true,'RangeMethod','Matched filter', ... 'Name','Range-Doppler Scope', ... 'Position',[560 375 560 420],'ResponseUnits','db', ... 'RangeUnits','m','DopplerFFTLength',1024, ... 'DopplerOutput','Speed','OperatingFrequency',fc, ... 'SampleRate',fs,'PropagationSpeed',c);

scope(( my 5120 x 100000 complex double),mfcoeffs);

How can I get my mfcoeffs? During my researches I found What is matched filter in QPSK signal?. But It does not answer my question. Also, I found https://www.mathworks.com/help/phased/ref/phased.phasecodedwaveform.getmatchedfilter.html ('getMatchedFilter' that uses a phase-coded waveform ) to get my mfcoeffs.

But according to https://www.mathworks.com/help/phased/ug/phase-coded-waveforms.html it is recommended to use another waveform instead of a phase-coded waveform when you need to detect or track high-speed targets or Phase-coded waveforms tend to perform poorly when signals have Doppler shifts. it is my case.

So How can I get mfcoeffs?

[ - ]
Reply by jtp_1960November 7, 2021