+ plot error versus freq and timing offset
+ plot pro acquisition versus freq offset, timing and freq sep and together
+ plot total acquist prob at various SNRs ... maybe mean number of frames to sync?
-
+ [ ] replace genie EsNo est used for ldpc dec
+ [ ] clean up text
#}
function [sim_out rx states] = run_sim(sim_in)
timing_en = states.timing_en = sim_in.timing_en;
states.foff_est_en = foff_est_en = sim_in.foff_est_en;
states.phase_est_en = phase_est_en = sim_in.phase_est_en;
-
+
if verbose
printf("Rs:..........: %4.2f\n", Rs);
printf("M:...........: %d\n", M);
printf("Nrowsperframe: %d\n", Nrowsperframe);
printf("Nsamperframe.: %d\n", Nsamperframe);
end
-
+
% Important to define run time in seconds so HF model will evolve the same way
% for different pilot insertion rates. So lets work backwards from approx
% seconds in run to get Nbits, the total number of payload data bits
printf("Nrp....: %d (number of rows including pilots)\n", Nrp);
end
+ % Optional LPDC code -----------------------------------------------
+
+ if isfield(sim_in, "ldpc_code")
+ assert(bps == 2, "Only QPSK supported for LDPC so far.....");
+ HRA = sim_in.ldpc_code;
+ [aNr aNc] = size(HRA);
+ rate = states.rate = (aNc-aNr)/aNc;
+ assert(aNc == Nbitsperframe, "Dude: Num cols of LDPC HRA must == Nbitsperframe");
+ [H_rows, H_cols] = Mat2Hrows(HRA);
+ code_param.H_rows = H_rows;
+ code_param.H_cols = H_cols;
+ code_param.P_matrix = [];
+ code_param.data_bits_per_frame = length(code_param.H_cols) - length( code_param.P_matrix );
+ code_param.code_bits_per_frame = aNc;
+ assert(aNr == Nbitsperframe*rate);
+
+ ldpc_en = states.ldpc_en = 1;
+ modulation = states.ldpc_modulation = 'QPSK';
+ mapping = states.ldpc_mapping = 'gray';
+ demod_type = states.ldpc_demod_type = 0;
+ decoder_type = states.ldpc_decoder_type = 0;
+ max_iterations = states.ldpc_max_iterations = 100;
+
+ code_param.S_matrix = CreateConstellation( modulation, 4, mapping );
+
+ states.code_param = code_param;
+ end
+
% set up HF model ---------------------------------------------------------------
if hf_en
rand('seed',1);
randn('seed',1);
- EbNo = bps * (10 .^ (EbNodB(nn)/10));
- variance = 1/(M*EbNo/2);
+ EsNo = bps * (10 .^ (EbNodB(nn)/10));
+ variance = 1/(M*EsNo/2);
Nsam = Nrp*(M+Ncp);
% generate tx bits and run OFDM modulator
+ % note for reasons unknown LdpcEncode() returns garbage if we use > 0.5 rather than round()
- tx_bits = rand(1,Nbits) > 0.5;
+ tx_data_bits = round(rand(1,Nbits*rate));
- tx = [];
+ tx = []; tx_bits = [];
for f=1:Nframes
- tx = [tx ofdm_mod(states, tx_bits((f-1)*Nbitsperframe+1:f*Nbitsperframe))];
+ st = (f-1)*Nbitsperframe*rate+1; en = st + Nbitsperframe*rate - 1;
+ if ldpc_en
+ codeword = LdpcEncode(tx_data_bits(st:en), code_param.H_rows, code_param.P_matrix);
+ else
+ codeword = tx_data_bits(st:en);
+ end
+ tx = [tx ofdm_mod(states, codeword)];
+ tx_bits = [tx_bits codeword];
end
% add extra row of pilots at end, to allow one frame simulations,
delta_t_log = [];
timing_est_log = [];
foff_est_hz_log = [];
- Nerrs_log = [];
+ Nerrs_log = []; Nerrs_coded_log = [];
rx_bits = []; rx_np = [];
% reset some states for each EbNo simulation point
% calculate BER stats as a block, after pilots extracted
errors = xor(tx_bits, rx_bits);
- Nerrs = sum(errors);
+ Terrs = sum(errors);
+
+ Terrs_coded = 0; Tper_coded = 0;
for f=1:Nframes
- st = (f-1)*Nbitsperframe+1; en = st + Nbitsperframe-1;
+ st = (f-1)*Nbitsperframe+1; en = st + Nbitsperframe - 1;
Nerrs_log(f) = sum(xor(tx_bits(st:en), rx_bits(st:en)));
+
+ % optional LDPC decode
+
+ if ldpc_en
+ st = (f-1)*Nbitsperframe/bps + 1;
+ en = st + Nbitsperframe/bps - 1;
+ rx_codeword = ldpc_dec(code_param, max_iterations, demod_type, decoder_type, rx_np(st:en), EsNo);
+ st = (f-1)*Nbitsperframe*rate + 1;
+ en = st + Nbitsperframe*rate - 1;
+ Nerrs_coded = sum(xor(tx_data_bits(st:en), rx_codeword(1:Nbitsperframe*rate)));
+ Nerrs_coded_log(f) = Nerrs_coded;
+ Terrs_coded += Nerrs_coded;
+ if Nerrs_coded
+ Tper_coded++;
+ end
+ end
end
- printf("EbNodB: %3.2f BER: %5.4f Nbits: %d Nerrs: %d\n", EbNodB(nn), Nerrs/Nbits, Nbits, Nerrs);
+ printf("EbNodB: %3.2f BER: %5.4f Tbits: %d Terrs: %d\n", EbNodB(nn), Terrs/Nbits, Nbits, Terrs);
+ if ldpc_en
+ printf(" Coded BER: %5.4f Tbits: %d Terrs: %d PER: %5.4f\n", Terrs_coded/(Nbits*rate), Nbits*rate, Terrs_coded, Tper_coded/Nframes);
+ end
if verbose
title('Fine Freq');
figure(5); clf;
- plot(Nerrs_log);
-
+ if ldpc_en
+ subplot(211)
+ plot(Nerrs_log);
+ title("Uncoded Errors/frame");
+ subplot(212)
+ plot(Nerrs_coded_log);
+ title("Coded Errors/frame");
+ else
+ title("Errors/frame");
+ plot(Nerrs_log);
+ end
figure(6)
Tx = abs(fft(tx(1:Nsam).*hanning(Nsam)'));
end
- sim_out.ber(nn) = sum(Nerrs)/Nbits;
+ sim_out.ber(nn) = Terrs/Nbits;
sim_out.pilot_overhead = 10*log10(Ns/(Ns-1));
end
endfunction
sim_in.Tcp = 0.002;
sim_in.Rs = 1/Ts; sim_in.bps = 2; sim_in.Nc = 16; sim_in.Ns = 8;
- sim_in.Nsec = 5*(sim_in.Ns+1)/sim_in.Rs; % one frame
- %sim_in.Nsec = 30;
+ %sim_in.Nsec = 5*(sim_in.Ns+1)/sim_in.Rs; % one frame
+ sim_in.Nsec = 30;
- sim_in.EbNodB = 10;
+ sim_in.EbNodB = 100;
sim_in.verbose = 1;
sim_in.hf_en = 0;
sim_in.foff_hz = 0;
sim_in.foff_est_en = 1;
sim_in.phase_est_en = 1;
+ load HRA_112_112.txt
+ sim_in.ldpc_code = HRA_112_112;
+
run_sim(sim_in);
end
format;
more off;
-%run_single
+init_cml('/home/david/Desktop/cml/');
+
+run_single
%run_curves
%acquisition_histograms
-acquisition_test
+%acquisition_test
rate_fs_pilot_samples = states.pilots * W/states.M;
states.rate_fs_pilot_samples = [rate_fs_pilot_samples(states.M-states.Ncp+1:states.M) rate_fs_pilot_samples];
+
+ % LDPC code is optionally enabled
+
+ states.rate = 1.0;
+ states.ldpc_en = 0;
endfunction
+% NOTE: You will need to set the CML path in the call to init_cml() below
+% for you CML install. See lpdc.m for instructions on how to install
+% CML library
+
+function init_cml(path_to_cml)
+ currentdir = pwd;
+
+ if exist(path_to_cml, 'dir') == 7
+ cd(path_to_cml)
+ CmlStartup
+ cd(currentdir);
+ else
+ printf("\n---------------------------------------------------\n");
+ printf("Can't start CML in path: %s\n", path_to_cml);
+ printf("See CML path instructions at top of this script\n");
+ printf("-----------------------------------------------------\n\n");
+ assert(0);
+ end
+end
+
+
% --------------------------------------
% ofdm_mod - modulates one frame of bits
% --------------------------------------
endfunction
+function detected_data = ldpc_dec(code_param, max_iterations, demod_type, decoder_type, r, EsNo, fading)
+ if nargin == 6
+ fading = ones(1, length(r));
+ end
+
+ symbol_likelihood = Demod2D( r, code_param.S_matrix, EsNo, fading);
+
+ % initialize the extrinsic decoder input
+
+ input_somap_c = zeros(1, code_param.code_bits_per_frame );
+ bit_likelihood = Somap( symbol_likelihood, demod_type, input_somap_c );
+
+ input_decoder_c = bit_likelihood(1:code_param.code_bits_per_frame);
+
+ x_hat= MpDecode( -input_decoder_c, code_param.H_rows, code_param.H_cols, ...
+ max_iterations, decoder_type, 1, 1);
+ detected_data = x_hat(max_iterations,:);
+endfunction
+
projects / freetel-svn-tracking.git / commitdiff