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- refactored CFO fine and symbol generation

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git-svn-id: http://moon:8086/svn/matlab/trunk@69 801c6759-fa7c-4059-a304-17956f83a07c
This commit is contained in:
jens
2015-05-03 14:47:43 +00:00
parent b630a4d4b4
commit 7b52e9d66d
2 changed files with 75 additions and 50 deletions
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ofdm/ofdm_rx.m
+74 -49
View File
@@ -49,32 +49,32 @@ filter_z = [];
fileRemain = wav_size; fileRemain = wav_size;
% Timing coarse stuff % Timing coarse stuff
timingCoarse = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'started', 0, 'cp_off', 0, 'cp_off_', [], 'Nd', 0); timingCoarse = struct('Z', 0, 'started', 0, 'sync_counter', 20, 'sync', 0, 'cp_off', 0, 'cp_off_', [], 'Nd', 0);
% CFO coarse integer stuff % CFO coarse integer stuff
cfoCoarseInteger = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'started', 0, 'err', 0); cfoCoarseInteger = struct('Z', 0, 'started', 0, 'sync_counter', 20, 'sync', 0, 'f_err', 0);
% CFO coarse fractional stuff % CFO coarse fractional stuff
cfoCoarseFractional = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'started', 0, 'err', 0, 'err_', [], 'df', 0, 'df_', []); cfoCoarseFractional = struct('Z', 0, 'started', 0, 'sync_counter', 20, 'sync', 0, 'f_err', 0, 'f_err_', [], 'df', 0, 'df_', []);
% CFO Fine stuff % CFO Fine stuff
cfoFine = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'started', 0, 'err', 0, 'err_', [], 'df', 0, 'df_', [], 'Xlast', [], 'phi', 0, 'bin_track', 1); cfoFine = struct('Z', 0, 'started', 0, 'sync_counter', 20, 'sync', 0, 'f_err', 0, 'f_err_', [], 'df', 0, 'df_', [], 'Xlast', [], 'phi', 0, 'bin_track', 1);
% Frame timing stuff % Frame timing stuff
frameTiming = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'started', 0, 'kc_max', -1000, 'n', 0, 'n_max', 0); frameTiming = struct('Z', 0, 'started', 0, 'sync_counter', 20, 'sync', 0, 'kc_max', -1000, 'n', 0, 'n_max', 0);
% Equalization stuff % Equalization stuff
MIN_ABS_H = 1e-10; MIN_ABS_H = 1e-10;
equalizer = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'started', 0, 's', 0, 'm', 0, 'kk', 1, 'eps_abs_h', MIN_ABS_H); equalizer = struct('Z', 0, 'started', 0, 'sync_counter', 20, 'sync', 0, 'sync_frame_num', 0, 'f_err', 1000, 'f_err_', [], 's', 0, 'm', 0, 'kk', 1, 'eps_abs_h', MIN_ABS_H);
[W_syms, W_pilots] = calcWiener(drm_mode, drm_bw); [W_syms, W_pilots] = calcWiener(drm_mode, drm_bw);
H_syms = []; H_syms = [];
H_pilots = []; H_pilots = [];
H_ = []; H_ = [];
df_track = 1000; df_track = 0;
df_track_ = []; df_track_ = [];
symbol_count = -1;
symbols_per_frame = ofdm_drm_params.nspf; symbols_per_frame = ofdm_drm_params.nspf;
symbols_to_delay = ofdm_drm_params.y; symbols_to_delay = ofdm_drm_params.y;
frames_per_window = 2*ofdm_drm_params.y; frames_per_window = 2*ofdm_drm_params.y;
@@ -168,14 +168,14 @@ while(fileRemain > fileChunkSize)
if (~isempty(x)) if (~isempty(x))
[d_bin, valid, cfoCoarseInteger.Z] = cfo_coarse_int(x(Ng+1:N+Ng), N, carrier_pilot, 11, cfoCoarseInteger.Z); [d_bin, valid, cfoCoarseInteger.Z] = cfo_coarse_int(x(Ng+1:N+Ng), N, carrier_pilot, 11, cfoCoarseInteger.Z);
if valid if valid
cfoCoarseInteger.err = -d_bin(1)/N*fs; cfoCoarseInteger.f_err = -d_bin(1)/N*fs;
if (cfoCoarseInteger.sync_counter > 0) if (cfoCoarseInteger.sync_counter > 0)
cfoCoarseInteger.sync_counter = cfoCoarseInteger.sync_counter - 1; cfoCoarseInteger.sync_counter = cfoCoarseInteger.sync_counter - 1;
else else
cfoCoarseInteger.sync = 1; cfoCoarseInteger.sync = 1;
% Reset buffer to Cp offset % Reset buffer to Cp offset
buf_recv.setReadIndex(timingCoarse.cp_off); buf_recv.setReadIndex(timingCoarse.cp_off);
fprintf(' (err_fi=%f)\n', cfoCoarseInteger.err); fprintf(' (f_err_i=%f)\n', cfoCoarseInteger.f_err);
end end
end end
end end
@@ -189,30 +189,31 @@ while(fileRemain > fileChunkSize)
end end
x = buf_recv.read(N+Ng); x = buf_recv.read(N+Ng);
if (~isempty(x)) if (~isempty(x))
[err, cfoCoarseFractional.Z] = cfo_coarse_fract(x, N, Ng, Ng, timingCoarse.Nd, cfoCoarseFractional.Z); [f_err, cfoCoarseFractional.Z] = cfo_coarse_fract(x, N, Ng, Ng, timingCoarse.Nd, cfoCoarseFractional.Z);
cfoCoarseFractional.err_ = [cfoCoarseFractional.err_ err*fs]; cfoCoarseFractional.f_err_ = [cfoCoarseFractional.f_err_ f_err*fs];
if (cfoCoarseFractional.sync_counter > 0) if (cfoCoarseFractional.sync_counter > 0)
cfoCoarseFractional.sync_counter = cfoCoarseFractional.sync_counter - 1; cfoCoarseFractional.sync_counter = cfoCoarseFractional.sync_counter - 1;
else else
cfoCoarseFractional.sync = 1; cfoCoarseFractional.sync = 1;
cfoCoarseFractional.err = mean(cfoCoarseFractional.err_); cfoCoarseFractional.f_err = mean(cfoCoarseFractional.f_err_);
cfoCoarseFractional.df = cfoCoarseInteger.err + cfoCoarseFractional.err; cfoCoarseFractional.df = cfoCoarseInteger.f_err + cfoCoarseFractional.f_err;
cfoCoarseFractional.df_ = cfoCoarseInteger.err + cfoCoarseFractional.err_; cfoCoarseFractional.df_ = cfoCoarseInteger.f_err + cfoCoarseFractional.f_err_;
% Reset buffer to Cp offset % Reset buffer to Cp offset
buf_recv.setReadIndex(timingCoarse.cp_off); buf_recv.setReadIndex(timingCoarse.cp_off);
fprintf(' (err_ff=%f, df_est=%f)\n', cfoCoarseFractional.err, cfoCoarseFractional.df); fprintf(' (f_err_f=%f, df_est=%f)\n', cfoCoarseFractional.f_err, cfoCoarseFractional.df);
end end
end end
end end
% CFO Fine % Create symbols
if (cfoCoarseFractional.sync) if (cfoCoarseFractional.sync)
if (~cfoFine.started) if (~cfoFine.started)
cfoFine.started = 1; cfoFine.started = 1;
cfoFine.df = cfoCoarseFractional.df; df_track = cfoCoarseFractional.df;
fprintf('Creating Symbols\n');
fprintf('Fine fractional CFO acquisition\n'); fprintf('Fine fractional CFO acquisition\n');
end end
kn = fs/(2*pi*(1+Ng/N))/N; kn = fs/(2*pi*(1+Ng/N))/N;
@@ -221,32 +222,30 @@ while(fileRemain > fileChunkSize)
x = buf_recv.read(N+Ng); x = buf_recv.read(N+Ng);
if (~isempty(x)) 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];
if cfoFine.sync if equalizer.sync
cfoFine.df = cfoFine.df + 0.1*df_track; df_track = df_track + 0.1*equalizer.f_err;
else else
cfoFine.df = cfoFine.df + 0.1*mean(cfoFine.err(cfoFine.bin_track)); df_track = df_track + 0.1*cfoFine.f_err;
end
if (abs(df_track) < 0.1) & (cfoFine.sync == 0)
if cfoFine.sync_counter > 0
cfoFine.sync_counter = cfoFine.sync_counter - 1;
else
cfoFine.sync = 1;
fprintf('Enter fine tracking mode at frame %d\n', equalizer.kk);
end
end
cfoFine.df_ = [cfoFine.df_ cfoFine.df];
end end
df_track_ = [df_track_ df_track];
x = x.*exp(j*(2*pi*df_track/fs*(0:N+Ng-1)' + cfoFine.phi));
cfoFine.phi = cfoFine.phi + 2*pi*df_track/fs*(N+Ng);
X = fft(x(Ng+1:N+Ng));
buf_Z.write(X); buf_Z.write(X);
cfoFine.Xlast = X; symbol_count = symbol_count + 1;
% CFO Fine acquisition
if ~equalizer.sync
if (~isempty(cfoFine.Xlast))
Z = cfoFine.Xlast .* conj(X);
f_err = kn*angle(Z(bin_pilot));
cfoFine.f_err = mean(f_err(cfoFine.bin_track));
cfoFine.f_err_ = [cfoFine.f_err_ cfoFine.f_err];
end
cfoFine.Xlast = X;
end
end end
% Frame timing acquisition % Frame timing acquisition
@@ -299,7 +298,7 @@ while(fileRemain > fileChunkSize)
H_raw(carrier_gain_bins) = (H_); H_raw(carrier_gain_bins) = (H_);
H_gain_cell{equalizer.m+1} = (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); str = sprintf('Symbol %d, s=%d, m=%d, n=%d', symbol_count, equalizer.s, equalizer.m, equalizer.n);
if equalizer.kk > frames_per_window if equalizer.kk > frames_per_window
@@ -318,8 +317,19 @@ while(fileRemain > fileChunkSize)
% get frequency error % get frequency error
% correlate wiener filtered channel with raw estimate % correlate wiener filtered channel with raw estimate
df_track = fs/(2*pi*N)*angle(H_pilots * Hr' + equalizer.eps_abs_h); equalizer.f_err = fs/(2*pi*N)*angle(H_pilots * Hr' + equalizer.eps_abs_h);
df_track_ = [df_track_ df_track]; equalizer.f_err_ = [equalizer.f_err_ equalizer.f_err];
if (abs(equalizer.f_err) < 0.1) & (equalizer.sync == 0)
if equalizer.sync_counter > 0
equalizer.sync_counter = equalizer.sync_counter - 1;
else
equalizer.sync = 1;
equalizer.sync_frame_num = symbol_count;
fprintf('Enter fine tracking mode at frame %d\n', equalizer.sync_frame_num);
end
end
% check for too small values % check for too small values
rms_H = sqrt( abs( H_syms*H_syms' )/length(H_syms) ); rms_H = sqrt( abs( H_syms*H_syms' )/length(H_syms) );
@@ -383,14 +393,29 @@ 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}') 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; figure;
subplot(3, 1, 1) subplot(4, 1, 1)
plot(0:length(cfoCoarseFractional.df_)-1, cfoCoarseFractional.df_); grid; title('df_{coarse} (Acquisition)') plot(0:length(cfoCoarseFractional.df_)-1, cfoCoarseFractional.df_); grid; title('df_{coarse} (Acquisition)')
subplot(3, 1, 2) subplot(4, 1, 2)
plot(0:length(cfoFine.df_)-1, cfoFine.df_, 0:length(df_track_)-1, df_track_); grid; title('df_{fine} (Acquisition), df_{track}') plot(0:length(cfoFine.f_err_.')-1, cfoFine.f_err_.'); grid; title('Error(df_{fine}) (Acquisition)')
subplot(3, 1, 3) subplot(4, 1, 3)
plot(0:length(cfoFine.err_.')-1, cfoFine.err_.'); grid; title('Error(df_{fine}) (Acquisition)') plot(0:length(equalizer.f_err_)-1, equalizer.f_err_); grid; title('Error(df_{Eq}) (Track)')
hold on;
x = [equalizer.sync_frame_num equalizer.sync_frame_num];
a = axis();
y = [a(3) a(4)];
plot(x-1,y, 'r-');
hold off;
subplot(4, 1, 4)
plot(0:length(df_track_)-1, df_track_); grid; title('df_{track}')
hold on;
x = [equalizer.sync_frame_num equalizer.sync_frame_num];
a = axis();
y = [a(3) a(4)];
plot(x-1,y, 'r-');
hold off;
if 0 if 0
xout = [real(x) imag(x)]; xout = [real(x) imag(x)];
ofdm/timing_frame.m
+1 -1
View File
@@ -1,6 +1,6 @@
function [kc, valid, Zf] = frame_timing(Z, bins_timing_pilots, sym_per_frame, Zi) function [kc, valid, Zf] = frame_timing(Z, bins_timing_pilots, sym_per_frame, Zi)
N = length(Z) N = length(Z);
if (~isfield(Zi, 'valid')) if (~isfield(Zi, 'valid'))
Zi = struct('valid', 1, 'Zk', []); Zi = struct('valid', 1, 'Zk', []);