Added subband spectrum subplot to zoom in on spurious levels in case of e.g....

Added subband spectrum subplot to zoom in on spurious levels in case of e.g. WG sinus as subband 64.

applications/apertif/matlab/run_pfb.m

@@ -63,6 +63,7 @@ tb.subband_wg        = 1;           % subband range 0:tb.nof_subbands-1, can be
 %tb.subband_wg        = 12;
 tb.subband_wg        = 301;
 tb.subband_wg        = 301+1/13;
+tb.subband_wg        = 64;
 
 tb.phase             = 0;           % initial 'sinusoid' phase offset normalized to 2pi
 tb.sop               = 1;           % initial 'impulse' start index in range ctrl_wg.block_size = tb.subband_fft_size
@@ -423,7 +424,7 @@ xlabel(sprintf('Subbands 0:%d at time 0:%d [Tsub]', tb.nof_subbands-1, tb.nof_ts
 ylabel('Voltage');
 grid on;
 
-%% Plot PFFT subbands spectrum and phase for all tb.nof_tsub in one plot
+%% Plot PFFT subbands spectrum in Volt and phase for all tb.nof_tsub in one plot
 sub_ampl = abs(data_pfft_subband);
 sub_ampl_max = max(sub_ampl(:));
 sub_phase = angle(data_pfft_subband)*180/pi;
@@ -434,7 +435,8 @@ fig=fig+1;
 figure('position', [xfig+fig*dfig yfig-fig*dfig xfigw yfigw]);
 figure(fig);
 
-subplot(2,1,1);
+% Plot all Tsub full scale
+subplot(3,1,1);
 data = sub_ampl.';
 data = data(:);
 plot(tsub_all, data, 'k', tsub_all(sub_I), data(sub_I), 'ko', tsub_all(sub_Iplus1), data(sub_Iplus1), 'kx');
@@ -443,7 +445,20 @@ xlabel(sprintf('Subbands 0:%d at time 0:%d [Tsub]', tb.nof_subbands-1, tb.nof_ts
 ylabel('Voltage');
 grid on;
 
-subplot(2,1,2);
+% Plot subrange of Tsub after impulse response at low level scale to zoom
+% in on spurious levels, see also plot subband spectrogram
+subplot(3,1,2);
+data = sub_ampl.';
+data = data(:);
+plot(tsub_all, data, 'k', tsub_all(sub_I), data(sub_I), 'ko', tsub_all(sub_Iplus1), data(sub_Iplus1), 'kx');
+xlim([19.9 23.1])
+ylim([-0.001 0.005])
+title(sprintf('Subband data - spurious levels  (for WG subband = %6.3f)', tb.subband_wg));
+xlabel(sprintf('Subbands 0:%d at time 0:%d [Tsub]', tb.nof_subbands-1, tb.nof_tsub-1));
+ylabel('Voltage');
+grid on;
+
+subplot(3,1,3);
 data = sub_phase.';
 data = data(:);
 plot(tsub_all, data, 'k', tsub_all(sub_I), data(sub_I), 'ko', tsub_all(sub_Iplus1), data(sub_Iplus1), 'kx');