phased.CFARdetector Error: Number of columns of input signal cannot change during simulation.

I am trying to obtain a range-Doppler map using CFAR. I am aware of the CFARdetector2D, which gives another error (asked in a separate question).

Offending snippet:

[rng_det, rng_th] = CFAR1D(abs(IQ2D)', 1:200);

[dop_det, dop_th] = CFAR1D(abs(IQ2D), 1:512);

The error:

Error using phased.internal.AbstractVarSizeEngine/validateNumChannels

Number of columns of input signal cannot change during simulation.

Error in phased.CFARDetector/validateInputsImpl (line 233)

validateNumChannels(obj,x);

Error in cfar_rd_sawtooth (line 96)

[dop_det, dop_th] = CFAR1D(abs(IQ2D), 1:512);

IQ2D has dimensions 200x512. Transposing it results in dimensions 512x200. I set the CUT indices to the number of columns. Why would this work for the first line and not the second?

Code and data is attached.

Answer 1

[Dayalan Nair]

Got the 2D CFAR working, so there is no need for this. Would be interesting to know the cause, though.

EDIT: I have found, in another application, that this could be due to a zero input signal (zero vector input).