I built the small radar system with a PICmicro ramp generating and data logging circuit. I record the scattering data directly into MATLAB workspace.
My problem is that I couldn't use the RMA algorithm of Dr. Charvat's thesis with my data. I get the following error in MATLAB:
Error using griddedInterpolant
The point coordinates are not sequenced in strict monotonic
Error in interp1>Interp1D (line 335)
F = griddedInterpolant(X,V(:,1),method);
Error in interp1 (line 220)
Vq = Interp1D(X,V,Xq,method);
Error in rma_exp_m1 (line 180)
S_st(ii,:) = (interp1(Ky(ii,:), S_mf(ii,:), Ky_even));
IMO, probably I couldn't do the data conditioning properly.
As an example, I attached one of my recorded data. I moved the SAR system with 1cm increments for 91 positions. The frequency is swept with a center frequency of 2425E6 Hz and the BW is 221E6 Hz for each position. My ramp time is 180ms. The scattering data is recorded 145 times in a pulse. Hence the scattering matrix (S) is 91X145. How can I use RMA algorithm to obtain a SAR image using this data. Any help is greatly appreciated.
Thanks in advance.
Note: I couldn't attach the scattering data to the post hence shared the scattering file here: http://www.sendspace.com/file/96n7v7