From 7bb287e3035005e9b116d3b5b2045061ee94d159 Mon Sep 17 00:00:00 2001
From: Jens Ahrensfeld <jens@jayfield.org>
Date: Tue, 23 Mar 2021 15:08:51 +0000
Subject: [PATCH] - added

git-svn-id: http://moon:8086/svn/vhdl/trunk@1495 cc03376c-175c-47c8-b038-4cd826a8556b
---
 lib/radio/ddc/ghdl/tb_results.m | 57 +++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 lib/radio/ddc/ghdl/tb_results.m

diff --git a/lib/radio/ddc/ghdl/tb_results.m b/lib/radio/ddc/ghdl/tb_results.m
new file mode 100644
index 0000000..df714b3
--- /dev/null
+++ b/lib/radio/ddc/ghdl/tb_results.m
@@ -0,0 +1,57 @@
+% Read data
+function tb_results()
+%fa = 100.0;
+fa = textread('fa.txt')/1E6
+R = textread('ratio.txt');
+N = textread('nstages.txt');;
+M = 1;
+fa_dec = fa/R
+N_pfir = 63;
+
+I_out_dec = textread('i_dec.txt')';
+Q_out_dec = textread('q_dec.txt')';
+I_out_fir = textread('i_fir.txt')';
+Q_out_fir = textread('q_fir.txt')';
+
+N_dec = length(I_out_dec)-2*N_pfir;
+N_fft_dec = N_dec
+N_fft2_dec = N_fft_dec/2;
+
+N_fir = length(I_out_fir)-2*N_pfir;
+N_fft_fir = N_fir
+N_fft2_fir = N_fft_fir/2;
+
+fft_y2_fir = 2/N_fft_fir*abs(fft(I_out_fir(2*N_pfir+1:N_fft_fir+2*N_pfir).*hann(N_fft_fir)'));
+
+fft_y2_dec = 2/N_fft_dec*abs(fft(I_out_dec(2*N_pfir+1:N_fft_dec+2*N_pfir).*hann(N_fft_dec)'));
+
+f = (1:N_fft_dec)/N_fft_dec;
+g = (R*M)^N;
+H = abs(sin(pi*M.*f)./sin(pi.*f/R)).^N;
+
+[v, j] = max(fft_y2_dec(1:N_fft2_dec/2))
+H = v*H/H(j);
+
+audiowrite('iq.wav', 0.5*[I_out_dec' Q_out_dec'], 16000, 'BitsPerSample', 16);
+audiowrite('iq_cfir.wav', 0.5*[I_out_fir' Q_out_fir'], 8000, 'BitsPerSample', 16);
+
+% Output
+close all;
+
+plot(1:length(I_out_dec), I_out_dec, 1:length(Q_out_dec), Q_out_dec); grid;
+
+figure;
+cic_plot(M, N, R);
+
+figure;
+subplot(2,1,1)
+plot(fa/(R*N_fft_dec)*(0:N_fft2_dec),20*log10(fft_y2_dec(1:N_fft2_dec+1)), '-', fa/(R*N_fft_dec)*(0:N_fft2_dec),20*log10(H(1:N_fft2_dec+1)), 'r-');
+legend('CIC', 'Droop');
+xlabel('MHz');
+grid;
+subplot(2,1,2)
+plot(fa/(2*R*N_fft_fir)*(0:N_fft2_fir),20*log10(fft_y2_fir(1:N_fft2_fir+1)), '-');
+legend('CFIR');
+xlabel('MHz');
+grid;
+