[RX]
- streaming - added fancy buffer git-svn-id: http://moon:8086/svn/matlab/trunk@62 801c6759-fa7c-4059-a304-17956f83a07c
This commit is contained in:
+295
-268
@@ -1,9 +1,9 @@
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function ofdm_rx(filename, foff, flip_spec, SNR, with_cir, show_H)
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function ofdm_rx(filename, foff, flip_spec, SNR, show_H)
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%
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% [sym_out, H, W] = ofdm_rx(filename, foff, flip_spec, SNR, with_cir, show_H)
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% Example: ofdm_rx('drm-15435-if.wav', -174.65, 0, 400, 0, 1)
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% Example: ofdm_rx('xv.wav', 0, 0, 400, 0, 1)
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% or ofdm_rx('yv.wav', 0, 0, 400, 0, 1)
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% [sym_out, H, W] = ofdm_rx(filename, foff, flip_spec, SNR, show_H)
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% Example: ofdm_rx('drm-15435-if.wav', -174.65, 0, 400, 1)
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% Example: ofdm_rx('xv.wav', 0, 0, 400, 1)
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% or ofdm_rx('yv.wav', 0, 0, 400, 1)
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close all;
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@@ -12,204 +12,68 @@ drm_bw = '10k';
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[ofdm_drm_params, ofdm_spec_occ] = drm_params(drm_mode, drm_bw);
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pre_mix = 0;
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fs = 12000;
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N = 256;
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Ng = 64;
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[carrier_pilot, phi_pilot, mag_pilot] = getRefFreq(drm_mode);
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[carrier_time, phi_time, mag_time] = getRefTime(drm_mode);
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h_cir = [0 0 .1 -.2 .5 .2 -.1 0 0 ];
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% Read wav file
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[fsize fs4] = wavread(filename, 'size')
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[xwav, fs4, nbits] = wavread(filename, 0);
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wav_numCh = fsize(2);
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wav_size = fsize(1);
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% Generate signal
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[xwav fs_ nbits] = wavread(filename);
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[len ndim] = size(xwav);
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if (ndim == 2)
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fprintf('Mode: Baseband\n');
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x = xwav(:, 1) + j*xwav(:, 2);
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x = x.*exp(-j*(2*pi*(foff/fs_)*(0:len-1)'));
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elseif (ndim == 1)
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isModePassband = 0;
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if (wav_numCh == 1)
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fprintf('Mode: Passband\n');
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x = xwav - mean(xwav);
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x = xwav.*exp(-j*(2*pi*(0.25-foff/fs_)*(0:len-1)'));
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hlp = FIRCalcLowpass(12000/fs_, 15);
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x = filter(hlp, 1, x);
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% Downsample
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x = x(1:4:length(x));
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omega_xwav = (0.25-foff/fs4);
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isModePassband = 1;
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elseif (wav_numCh == 2)
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fprintf('Mode: Baseband\n');
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omega_xwav = (foff/fs4);
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else
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error('Cannot read file!');
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error('Cannot read file');
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end
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if with_cir
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x = filter(h_cir, 1, x);
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end
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buf_recv = buffer();
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buf_Z = buffer();
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x = x - mean(x);
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if flip_spec
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x = conj(x);
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end
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x = x./max(abs(x));
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xout = [real(x) imag(x)];
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wavwrite(xout,fs,nbits,'ofdm_rx.wav');
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fileChunkSize = N;
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fileCunkCounter = 0;
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phi_xwav = 0;
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filter_h = FIRCalcLowpass(0.25, 15);
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filter_z = [];
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% Modulate on carrier
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xup = upsample(x, 4);
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hlp = FIRCalcLowpass(0.25, 129);
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xup = filter(hlp, 1, xup);
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fileRemain = wav_size;
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y = exp(j*2*pi.*(0:length(xup)-1)'*0.25) .* xup;
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% Timing coarse stuff
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timingCoarse = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'cp_off', 0, 'cp_off_', [], 'Nd', 0);
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wavwrite(y,4*fs,nbits,'ofdm_rx_passband.wav');
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% CFO coarse integer stuff
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cfoCoarseInteger = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'df', 0);
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x = awgn(x, SNR, 'measured');
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K = fix((length(x))/(N+Ng))-1;
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% CFO coarse fractional stuff
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cfoCoarseFractional = struct('Z', 0, 'sync_counter', 200, 'sync', 0, 'err', 0, 'err_', [], 'df', 0, 'df_', []);
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% Timing coarse
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fprintf('Coarse timing acquisition\n');
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cp_off = 0;
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cp_off_ = [];
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Z = 0;
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for k=1:20
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xp = x((k-1)*(N+Ng)+1:k*(N+Ng));
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[cp_off, Nd, valid, Z] = timing_coarse(xp, N, Ng, Ng, Z);
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if (valid)
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cp_off_ = [cp_off_ cp_off];
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end
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end;
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cp_off = round(median(cp_off_))
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Nd = Nd
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% CFO Fine stuff
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cfoFine = struct('Z', 0, 'sync_counter', 200, 'sync', 0, 'err', 0, 'err_', [], 'df', 0, 'df_', [], 'Xlast', [], 'phi', 0, 'bin_track', 1);
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% Integer CFO coarse
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fprintf('Coarse integer CFO acquisition\n');
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fdet_coarse_Z = 0;
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Z_cfa_pre = 0;
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df_acq_coarse_int_ = [];
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valid_latency_count = 20;
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for k=1:200
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xp = x((k-1)*(N+Ng)+cp_off+1:k*(N+Ng)+cp_off);
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[d_bin, valid, fdet_coarse_Z] = cfo_coarse_int(xp(Ng+1:N+Ng), N, carrier_pilot, 11, fdet_coarse_Z);
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if valid
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df_acq_coarse_int = -d_bin(1)/N*fs;
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if valid_latency_count > 0
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valid_latency_count = valid_latency_count - 1;
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else
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break;
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end
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end
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end
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% Frame timing stuff
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frameTiming = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'kc_max', -1000, 'n_max', 0);
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fprintf('Coarse fractional CFO acquisition\n');
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% CFO coarse
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df_acq_coarse_fract_ = [];
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for k=1:200
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xp = x((k-1)*(N+Ng)+cp_off+1:k*(N+Ng)+cp_off);
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[domega_f, Z_cfa_pre] = cfo_coarse_fract(xp, N, Ng, Ng, Nd, Z_cfa_pre);
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df_acq_coarse_fract_ = [df_acq_coarse_fract_ domega_f*fs];
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end;
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df_acq_c = df_acq_coarse_int + mean(df_acq_coarse_fract_(10:200))
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df_acq_c_ = df_acq_coarse_int + df_acq_coarse_fract_;
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if pre_mix
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x1 = x.*exp(j*(2*pi*df_acq_c/fs.*(0:length(x)-1)'));
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df_acq_fine = 0;
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else
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x1 = x;
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df_acq_fine = df_acq_c;
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end
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% CFO Fine
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fprintf('Fine fractional CFO acquisition\n');
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Xlast = [];
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df_acq_fine_err = 0;
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df_acq_fine_err_ = [];
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df_acq_fine_ = [];
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kn = fs/(2*pi*(1+Ng/N))/N;
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x_ = [];
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Hp_ = [];
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Z_ = [];
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phi = 0.0;
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bin_track = 1;
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sym_pilot = exp(j*2*pi*phi_pilot'/1024);
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bin_pilot = c2i(N, carrier_pilot);
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for k=1:K,
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xp = x1((k-1)*(N+Ng)+cp_off+1:k*(N+Ng)+cp_off);
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xp = xp.*exp(j*(2*pi*df_acq_fine/fs*(0:N+Ng-1)' + phi));
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phi = phi + 2*pi*df_acq_fine/fs*(N+Ng);
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xp = xp(Ng+1:N+Ng);
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x_ = [x_' xp']';
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X = fft(xp);
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if (~isempty(Xlast))
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Z = Xlast .* conj(X);
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df_acq_fine_err = kn*angle(Z(bin_pilot));
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df_acq_fine_err_ = [df_acq_fine_err_ df_acq_fine_err];
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phi_p = angle(X(bin_pilot));
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mag_p = abs(X(bin_pilot));
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df_acq_fine = df_acq_fine + 0.1*mean(df_acq_fine_err(bin_track));
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df_acq_fine_ = [df_acq_fine_ df_acq_fine];
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Hp = X(bin_pilot)./conj(sym_pilot);
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Hp_ = [Hp_ Hp];
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Z_ = [Z_ X];
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end
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Xlast = X;
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end
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figure;
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plot(0:length(cp_off_)-1, cp_off_, 0:length(cp_off_)-1, cp_off*ones(size(cp_off_)), 'r-'); grid; title('cp_{off}')
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df_acq_fine_ = df_acq_fine_';
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figure;
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subplot(3, 1, 1)
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plot(0:length(df_acq_c_)-1, df_acq_c_); grid; title('df_{coarse} (Acquisition)')
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subplot(3, 1, 2)
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plot(0:length(df_acq_fine_)-1, df_acq_fine_); grid; title('df_{fine} (Acquisition)')
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subplot(3, 1, 3)
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plot(0:length(df_acq_fine_err_)-1, df_acq_fine_err_); grid; title('Error(df_{fine}) (Acquisition)')
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figure;
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Z_pilot = Z_(bin_pilot, 200:length(Z_))';
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plot(real(Z_pilot), imag(Z_pilot), '+'); grid; title('SymPilot_{Freq}');
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maxZ = max(max(abs(Z_pilot)));
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if (maxZ < 1)
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axis([-1 1 -1 1]);
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else
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axis([-maxZ maxZ -maxZ maxZ]);
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end
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fprintf('Frame timing acquisition\n');
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%% Detect start of DRM frame
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bins = c2i(N, carrier_time);
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kc_max = -1000;
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n_max = 0;
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skip_syms = ofdm_drm_params.nspf*4;
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for n=0:ofdm_drm_params.nspf-1
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frame_timing_Z = 0;
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k = skip_syms+n;
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for m=1:2
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[kc valid frame_timing_Z] = timing_frame(Z_(bins, k)', bins, ofdm_drm_params.nspf, frame_timing_Z);
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k = k + ofdm_drm_params.nspf;
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end
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if valid
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if kc > kc_max
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n_max = n;
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kc_max = kc;
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end
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end
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end
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frame_start = n_max
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fprintf('Channel estimation and symbol reception\n');
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% Equalization stuff
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MIN_ABS_H = 1e-10;
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equalizer = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 's', 0, 'm', 0, 'kk', 1, 'eps_abs_h', MIN_ABS_H);
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[W_syms, W_pilots] = calcWiener(drm_mode, drm_bw);
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figure;
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% Detect scattered gain pilots
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H_syms = [];
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H_pilots = [];
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H_ = [];
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df_track_ = [];
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symbols_per_frame = ofdm_drm_params.nspf;
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symbols_to_delay = ofdm_drm_params.y;
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frames_per_window = 2*ofdm_drm_params.y;
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@@ -235,100 +99,263 @@ fac_cell_list = ...
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[23, 35, 47, 65, 77],
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[]
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};
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s = 0;
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m = 0;
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H_syms = [];
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H_pilots = [];
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kk = 1;
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H_ = [];
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df_track_ = [];
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MIN_ABS_H = 1e-10;
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eps_abs_h = MIN_ABS_H;
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while(fileRemain > fileChunkSize)
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n0 = fileCunkCounter*fileChunkSize+1;
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n1 = (fileCunkCounter+1)*fileChunkSize;
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[xwav] = wavread(filename, [n0 n1]);
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if (~isModePassband)
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xwav = xwav(:, 1) + j*xwav(:, 2);
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end
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xwav = xwav - mean(xwav);
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start = skip_syms+frame_start;
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x = xwav.*exp(-j*(2*pi*omega_xwav*(0:fileChunkSize-1)' + phi_xwav));
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phi_xwav = mod(phi_xwav + 2*pi*omega_xwav*fileChunkSize, 2*pi);
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if flip_spec
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x = conj(x);
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end
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for k=start:length(Z_)
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%shifted symbol index
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n = rem(m+symbols_to_delay-1, ofdm_drm_params.y);
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[carrier_gain, phi_gain, mag_gain] = getRefGain(ofdm_drm_params, ofdm_spec_occ, s);
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carrier_gain_bins = c2i(N, carrier_gain);
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H_ = transpose(Z_(carrier_gain_bins, k))./(mag_gain.*exp(j*2*pi*phi_gain/1024));
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H_raw(carrier_gain_bins) = (H_);
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H_gain_cell{m+1} = (H_);
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str = sprintf('Frame %d, s=%d, m=%d, n=%d', k, s, m, n);
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if kk > frames_per_window
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ii = 1+mod(m+symbols_to_delay-1+(0:frames_per_window-1), frames_per_window);
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H_gain = [H_gain_cell{ii}];
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H_syms = H_gain*W_syms{n+1};
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H_pilots = (H_gain)*W_pilots{n+1};
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% Get the correctly delayed symbols
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sym = Z_(carrier_indexes, k-symbols_to_delay).';
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% Get the correctly delayed raw channel estimate
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Hr = H_gain_cell{mod(m-1, frames_per_window)+1};
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% get frequency error
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% correlate wiener filtered channel with raw estimate
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df_track = fs/(2*pi*N)*angle(H_pilots * Hr' + eps_abs_h);
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df_track_ = [df_track_ df_track];
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% check for too small values
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rms_H = sqrt( abs( H_syms*H_syms' )/length(H_syms) );
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eps_abs_h = max( rms_H/20, MIN_ABS_H ); %quick and dirty fixed settings
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H_too_small_index = find( abs(H_syms)<eps_abs_h );
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H_syms( H_too_small_index ) = eps_abs_h;
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% equalize symbol
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sym_eq = sym ./ H_syms;
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if 0
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subplot(2, 1, 1)
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plot(1:length(Hr), abs(Hr), 'b-', 1:length(H_pilots), abs(H_pilots), 'r-'); grid;
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subplot(2, 1, 2)
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plot(1:length(Hr), angle(Hr), 'b-', 1:length(H_pilots), angle(H_pilots), 'r-'); grid;
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title(str);
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pause(0.01);
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end
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if 1
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if show_H
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H_raw(1:2:N) = H_raw(2:2:N);
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subplot(3, 1, 1)
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plot(carriers, abs(H_raw(carrier_indexes)), 'b-', carriers, abs(H_syms), 'r-'); grid; title('abs(H_{syms})'); axis([ofdm_spec_occ.kmin ofdm_spec_occ.kmax 0 15+0*max(abs(H_syms))]); title(str);
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subplot(3, 1, 2)
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plot(carriers, angle(H_raw(carrier_indexes)), 'b-', carriers, angle(H_syms), 'r-'); grid; title('phi(H_{syms})'); axis([ofdm_spec_occ.kmin ofdm_spec_occ.kmax -4 4]); title(str);
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subplot(3, 1, 3)
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plot(carriers, abs(sym_eq), 'b-'); grid; title('abs(Sym_{Eq})'); axis([ofdm_spec_occ.kmin ofdm_spec_occ.kmax 0 2]); title(str);
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hold on;
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for b=c2i(N, carrier_pilot)
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x = [b b];
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y = [0 2];
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plot(x-1,y, 'r-');
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% add noise
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x = awgn(x, SNR, 'measured');
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if (isModePassband)
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[x, filter_z] = filter(filter_h, 1, x, filter_z);
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buf_recv.write(x(1:4:length(x)));
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else
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buf_recv.write(x);
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end
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% --------------------------------------------------------------
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% Timing coarse
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if (~timingCoarse.sync)
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x = buf_recv.read(N+Ng);
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[cp_off, Nd, valid, timingCoarse.Z] = timing_coarse(x, N, Ng, Ng, timingCoarse.Z);
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if (valid)
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timingCoarse.cp_off_ = [timingCoarse.cp_off_ cp_off];
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if (timingCoarse.sync_counter > 0)
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timingCoarse.sync_counter = timingCoarse.sync_counter - 1;
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else
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timingCoarse.sync = 1;
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end
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hold off;
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pause(0.01);
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else
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fac_c = fac_cell_list{mod(s-symbols_to_delay, symbols_per_frame)+1};
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if (~isempty(fac_c))
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fac_i = fac_c - ofdm_spec_occ.kmin + 1;
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hold on;
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plot(sym_eq(fac_i), '+', 'MarkerSize', 4);
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pause(0.01);
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grid; title('FAC'); axis([-1 1 -1 1]);
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hold off;
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end;
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if (timingCoarse.sync)
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timingCoarse.cp_off = round(median(timingCoarse.cp_off_));
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timingCoarse.Nd = Nd;
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Nd = timingCoarse.Nd
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cp_off = timingCoarse.cp_off
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% Reset buffer to Cp offset
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buf_recv.setReadIndex(timingCoarse.cp_off);
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end
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end
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|
||||
% Integer CFO coarse
|
||||
if (timingCoarse.sync) && (~cfoCoarseInteger.sync)
|
||||
x = buf_recv.read(N+Ng);
|
||||
if (~isempty(x))
|
||||
[d_bin, valid, cfoCoarseInteger.Z] = cfo_coarse_int(x(Ng+1:N+Ng), N, carrier_pilot, 11, cfoCoarseInteger.Z);
|
||||
if valid
|
||||
cfoCoarseInteger.df = -d_bin(1)/N*fs;
|
||||
if (cfoCoarseInteger.sync_counter > 0)
|
||||
cfoCoarseInteger.sync_counter = cfoCoarseInteger.sync_counter - 1;
|
||||
else
|
||||
cfoCoarseInteger.sync = 1;
|
||||
end
|
||||
end
|
||||
end
|
||||
end
|
||||
|
||||
% Fractional CFO coarse
|
||||
if (cfoCoarseInteger.sync) && (~cfoCoarseFractional.sync)
|
||||
x = buf_recv.read(N+Ng);
|
||||
if (~isempty(x))
|
||||
[err, cfoCoarseFractional.Z] = cfo_coarse_fract(x, N, Ng, Ng, Nd, cfoCoarseFractional.Z);
|
||||
cfoCoarseFractional.err_ = [cfoCoarseFractional.err_ err*fs];
|
||||
|
||||
if (cfoCoarseFractional.sync_counter > 0)
|
||||
cfoCoarseFractional.sync_counter = cfoCoarseFractional.sync_counter - 1;
|
||||
else
|
||||
cfoCoarseFractional.sync = 1;
|
||||
cfoCoarseFractional.df = cfoCoarseInteger.df + mean(cfoCoarseFractional.err_);
|
||||
cfoCoarseFractional.df_ = cfoCoarseInteger.df + cfoCoarseFractional.err_;
|
||||
cfoFine.df = cfoCoarseFractional.df;
|
||||
end
|
||||
end
|
||||
end
|
||||
kk = kk + 1;
|
||||
m = mod(m+1, frames_per_window);
|
||||
s = mod(s + 1, symbols_per_frame);
|
||||
end
|
||||
|
||||
% CFO Fine
|
||||
if (cfoCoarseFractional.sync)
|
||||
kn = fs/(2*pi*(1+Ng/N))/N;
|
||||
sym_pilot = exp(j*2*pi*phi_pilot'/1024);
|
||||
bin_pilot = c2i(N, carrier_pilot);
|
||||
|
||||
x = buf_recv.read(N+Ng);
|
||||
if (~isempty(x))
|
||||
x = x.*exp(j*(2*pi*cfoFine.df/fs*(0:N+Ng-1)' + cfoFine.phi));
|
||||
cfoFine.phi = cfoFine.phi + 2*pi*cfoFine.df/fs*(N+Ng);
|
||||
X = fft(x(Ng+1:N+Ng));
|
||||
if (~isempty(cfoFine.Xlast))
|
||||
Z = cfoFine.Xlast .* conj(X);
|
||||
cfoFine.err = kn*angle(Z(bin_pilot));
|
||||
cfoFine.err_ = [cfoFine.err_ cfoFine.err];
|
||||
cfoFine.df = cfoFine.df + 0.1*mean(cfoFine.err(cfoFine.bin_track));
|
||||
cfoFine.df_ = [cfoFine.df_ cfoFine.df];
|
||||
buf_Z.write(X);
|
||||
end
|
||||
cfoFine.Xlast = X;
|
||||
end
|
||||
|
||||
bins = c2i(N, carrier_time);
|
||||
skip_syms = ofdm_drm_params.nspf*4;
|
||||
% Frame timing acquisition
|
||||
if (~frameTiming.sync) && (buf_Z.len() >= (N*(ofdm_drm_params.nspf+skip_syms)))
|
||||
buf_Z.setReadIndex(N*skip_syms);
|
||||
for n=0:ofdm_drm_params.nspf-1
|
||||
frameTiming.Z = 0;
|
||||
k = skip_syms+n;
|
||||
Z = buf_Z.read(N);
|
||||
if ~isempty(Z)
|
||||
for m=1:2
|
||||
[kc valid frameTiming.Z] = timing_frame(Z(bins)', bins, ofdm_drm_params.nspf, frameTiming.Z);
|
||||
k = k + ofdm_drm_params.nspf;
|
||||
end
|
||||
if valid
|
||||
if kc > frameTiming.kc_max
|
||||
frameTiming.n_max = n;
|
||||
frameTiming.kc_max = kc;
|
||||
end
|
||||
end
|
||||
end
|
||||
end
|
||||
if ~isempty(Z)
|
||||
buf_Z.setReadIndex(N*(frameTiming.n_max));
|
||||
frameTiming.sync = 1;
|
||||
frame_start = frameTiming.n_max
|
||||
end
|
||||
end
|
||||
|
||||
if (frameTiming.sync)
|
||||
|
||||
Z = transpose(buf_Z.read(N));
|
||||
if ~isempty(Z)
|
||||
|
||||
equalizer.n = rem(equalizer.m + symbols_to_delay-1, ofdm_drm_params.y);
|
||||
|
||||
[carrier_gain, phi_gain, mag_gain] = getRefGain(ofdm_drm_params, ofdm_spec_occ, equalizer.s);
|
||||
carrier_gain_bins = c2i(N, carrier_gain);
|
||||
H_ = Z(carrier_gain_bins)./(mag_gain.*exp(j*2*pi*phi_gain/1024));
|
||||
|
||||
H_raw(carrier_gain_bins) = (H_);
|
||||
H_gain_cell{equalizer.m+1} = (H_);
|
||||
|
||||
str = sprintf('Frame %d, s=%d, m=%d, n=%d', equalizer.kk, equalizer.s, equalizer.m, equalizer.n);
|
||||
|
||||
if equalizer.kk > frames_per_window
|
||||
|
||||
ii = 1+mod(equalizer.m+symbols_to_delay-1+(0:frames_per_window-1), frames_per_window);
|
||||
|
||||
H_gain = [H_gain_cell{ii}];
|
||||
H_syms = H_gain*W_syms{equalizer.n+1};
|
||||
H_pilots = (H_gain)*W_pilots{equalizer.n+1};
|
||||
|
||||
% Get the correctly delayed symbols
|
||||
Z = buf_Z.readAt(N, -N*symbols_to_delay);
|
||||
sym = Z(carrier_indexes).';
|
||||
|
||||
% Get the correctly delayed raw channel estimate
|
||||
Hr = H_gain_cell{mod(equalizer.m-1, frames_per_window)+1};
|
||||
|
||||
% get frequency error
|
||||
% correlate wiener filtered channel with raw estimate
|
||||
df_track = fs/(2*pi*N)*angle(H_pilots * Hr' + equalizer.eps_abs_h);
|
||||
df_track_ = [df_track_ df_track];
|
||||
|
||||
% check for too small values
|
||||
rms_H = sqrt( abs( H_syms*H_syms' )/length(H_syms) );
|
||||
equalizer.eps_abs_h = max( rms_H/20, MIN_ABS_H ); %quick and dirty fixed settings
|
||||
H_too_small_index = find( abs(H_syms)<equalizer.eps_abs_h );
|
||||
H_syms( H_too_small_index ) = equalizer.eps_abs_h;
|
||||
|
||||
% equalize symbol
|
||||
sym_eq = sym ./ H_syms;
|
||||
if 0
|
||||
subplot(2, 1, 1)
|
||||
plot(1:length(Hr), abs(Hr), 'b-', 1:length(H_pilots), abs(H_pilots), 'r-'); grid;
|
||||
subplot(2, 1, 2)
|
||||
plot(1:length(Hr), angle(Hr), 'b-', 1:length(H_pilots), angle(H_pilots), 'r-'); grid;
|
||||
title(str);
|
||||
pause(0.01);
|
||||
end
|
||||
if 1
|
||||
if show_H
|
||||
H_raw(1:2:N) = H_raw(2:2:N);
|
||||
subplot(3, 1, 1)
|
||||
plot(carriers, abs(H_raw(carrier_indexes)), 'b-', carriers, abs(H_syms), 'r-'); grid; title('abs(H_{syms})'); axis([ofdm_spec_occ.kmin ofdm_spec_occ.kmax 0 15+0*max(abs(H_syms))]); title(str);
|
||||
subplot(3, 1, 2)
|
||||
plot(carriers, angle(H_raw(carrier_indexes)), 'b-', carriers, angle(H_syms), 'r-'); grid; title('phi(H_{syms})'); axis([ofdm_spec_occ.kmin ofdm_spec_occ.kmax -4 4]); title(str);
|
||||
subplot(3, 1, 3)
|
||||
plot(carriers, abs(sym_eq), 'b-'); grid; title('abs(Sym_{Eq})'); axis([ofdm_spec_occ.kmin ofdm_spec_occ.kmax 0 2]); title(str);
|
||||
hold on;
|
||||
for b=c2i(N, carrier_pilot)
|
||||
x = [b b];
|
||||
y = [0 2];
|
||||
plot(x-1,y, 'r-');
|
||||
end
|
||||
hold off;
|
||||
|
||||
pause(0.01);
|
||||
else
|
||||
fac_c = fac_cell_list{mod(equalizer.s-symbols_to_delay, symbols_per_frame)+1};
|
||||
if (~isempty(fac_c))
|
||||
fac_i = fac_c - ofdm_spec_occ.kmin + 1;
|
||||
hold on;
|
||||
plot(sym_eq(fac_i), '+', 'MarkerSize', 4);
|
||||
pause(0.01);
|
||||
grid; title('FAC'); axis([-1 1 -1 1]);
|
||||
hold off;
|
||||
end
|
||||
end
|
||||
end
|
||||
end
|
||||
equalizer.kk = equalizer.kk + 1;
|
||||
equalizer.m = mod(equalizer.m + 1, frames_per_window);
|
||||
equalizer.s = mod(equalizer.s + 1, symbols_per_frame);
|
||||
end
|
||||
end
|
||||
end
|
||||
% --------------------------------------------------------------
|
||||
fileRemain = fileRemain - fileChunkSize;
|
||||
fileCunkCounter = fileCunkCounter + 1;
|
||||
end
|
||||
|
||||
figure;
|
||||
plot(0:length(timingCoarse.cp_off_)-1, timingCoarse.cp_off_, 0:length(timingCoarse.cp_off_)-1, timingCoarse.cp_off*ones(size(timingCoarse.cp_off_)), 'r-'); grid; title('cp_{off}')
|
||||
|
||||
figure;
|
||||
subplot(3, 1, 1)
|
||||
plot(0:length(cfoCoarseFractional.df_)-1, cfoCoarseFractional.df_); grid; title('df_{coarse} (Acquisition)')
|
||||
|
||||
subplot(3, 1, 2)
|
||||
plot(0:length(cfoFine.df_)-1, cfoFine.df_); grid; title('df_{fine} (Acquisition)')
|
||||
|
||||
subplot(3, 1, 3)
|
||||
plot(0:length(cfoFine.err_.')-1, cfoFine.err_.'); grid; title('Error(df_{fine}) (Acquisition)')
|
||||
|
||||
if 0
|
||||
xout = [real(x) imag(x)];
|
||||
wavwrite(xout,fs,nbits,'rx_x.wav');
|
||||
|
||||
% Modulate on carrier
|
||||
xup = upsample(x, 4);
|
||||
hlp = FIRCalcLowpass(0.25, 129);
|
||||
xup = filter(hlp, 1, xup);
|
||||
|
||||
y = exp(j*2*pi.*(0:length(xup)-1)'*0.25) .* xup;
|
||||
|
||||
wavwrite(y,fs4,nbits,'rx_y.wav');
|
||||
|
||||
end
|
||||
|
||||
|
||||
Reference in New Issue
Block a user