diff --git a/lib/radio/nco/sim/tb_mix_results.m b/lib/radio/nco/sim/tb_mix_results.m
index 1676a1c..5997fea 100644
--- a/lib/radio/nco/sim/tb_mix_results.m
+++ b/lib/radio/nco/sim/tb_mix_results.m
@@ -2,12 +2,16 @@
 function tb_mix_results()
 fa = 100.0;
 f = TEXTREAD('freq.txt')*1E-6
+R = 128;
+fa_dec = fa/R
+N_pfir = 63;
 
 I_in = TEXTREAD('i_in.txt')';
 I_out = TEXTREAD('i_out.txt')';
+Q_out = TEXTREAD('q_out.txt')';
 
-N= length(I_out);
-N_fft = N
+N= length(I_out)
+N_fft = N;
 N_fft2 = N_fft/2;
 
 fft_y2 = 2/N_fft*abs(fft(I_out(1:N_fft).*hann(N_fft)'));
@@ -22,9 +26,35 @@ fft_y3 = 2/N_fft*abs(fft(I_in(1:N_fft).*hann(N_fft)'));
 max_ditherd_spur_freq = (i*fa/N_fft);
 max_ditherd_spur_value = 20*log10(v);
 
+I_out_dec = cic_filter(R, 1, 3, I_out);
+Q_out_dec = cic_filter(R, 1, 3, Q_out);
+N_dec = length(I_out_dec)-2*N_pfir;
+N_fft_dec = N_dec
+N_fft2_dec = N_fft_dec/2;
+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)'));
+
+pfir_b = sinc(0.1*(-(N_pfir-1)/2:1:(N_pfir)/2));
+pfir_b = pfir_b/sum(pfir_b).*blackman(N_pfir)';
+I_out_dec_pfir = filter(pfir_b, 1, I_out_dec);
+Q_out_dec_pfir = filter(pfir_b, 1, Q_out_dec);
+fft_y2_dec_pfir = 2/N_fft_dec*abs(fft(I_out_dec_pfir(2*N_pfir+1:N_fft_dec+2*N_pfir).*hann(N_fft_dec)'));
+
 % Output
 close all;
 
+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(fft_y2_dec_pfir(1:N_fft2_dec+1)), '-'); grid;
+
+figure;
+plot(1:length(I_out_dec_pfir), I_out_dec_pfir, 1:length(Q_out_dec_pfir), Q_out_dec_pfir); grid;
+
+figure;
+freqz(pfir_b, 1, 1000);
+
+figure;
+plot(pfir_b); grid;
+
+
+figure;
 subplot(2,1,1)
 plot(fa/N_fft*(0:N_fft2),20*log10(fft_y2(1:N_fft2+1)), '-', fa/N_fft*(0:N_fft2), max_spur_value*ones(1,N_fft2+1), 'r-', [max_spur_freq], [max_spur_value], 'ro'); grid;
 spur_legend = sprintf('Max. spur %.1fdB at %.3fMHz', max_spur_value, max_spur_freq);
@@ -43,6 +73,8 @@ ylabel('dB');
 xlabel('f/MHz');
 axis([0 fa/2 -140 0]);
 
+plot(1:N, I_out, 1:N, Q_out); grid;
+
 function [max_i, max_v] = get_maxpur(spec, fa, f)
 max_v = 0;
 max_i = 0;