Phased Array System Toolbox: DOA with MVDREstimator using output data after Range-Doppler FFTs

Hi,

I'm trying to estimate the DOA of signal using MVDREstimator from Phased Array System Toolbox. I have read the following example for using the MVDREstimator (https://de.mathworks.com/help/phased/examples/direction-of-arrival-estimation-with-beamscan-mvdr-and-music.html).

And my problem is:

- The "mvdrspatialspect" takes raw signal as input data. However I want to pass data after Range-Doppler Map (FMCW) as input data to "mvdrspatialspect". How can I do this? Is there any example which does the similar thing?

ang1 = [30; 0]; ang2 = [40; 0];
signal = sensorsig(pos,Nsamp,[ang1 ang2],nPower);

mvdrspatialspect = phased.MVDREstimator('SensorArray',ula,...
        'OperatingFrequency',fc,'ScanAngles',-90:90,...
        'DOAOutputPort',true,'NumSignals',2);
[~,ang] = mvdrspatialspect(signal)
plotSpectrum(mvdrspatialspect);

Thanks,

Bien

Answer 1

[Honglei Chen]

To perform DOA estimation, the data input has to be across number of channels, i.e., number of elements in the array. On the other hand, in theory you can generate a range-Doppler map for each element for muleiple sweeps. Therefore, as long as you use the same operation to generate the range-Doppler map, you can try to reshape the map into a vector and then pass the vectors from all elements into DOA. This being said, you could also just pass the original received siganl across the array to DOA, there is no reason you have to do range-Doppler response first.

HTH