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+% tfsk.m
+% Author: Brady O'Brien 8 February 2016
+
+
+
+% Copyright 2016 David Rowe
+%
+% All rights reserved.
+%
+% This program is free software; you can redistribute it and/or modify
+% it under the terms of the GNU Lesser General Public License version 2.1, as
+% published by the Free Software Foundation. This program is
+% distributed in the hope that it will be useful, but WITHOUT ANY
+% WARRANTY; without even the implied warranty of MERCHANTABILITY or
+% FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+% License for more details.
+%
+% You should have received a copy of the GNU Lesser General Public License
+% along with this program; if not, see <http://www.gnu.org/licenses/>.
+
+
+% Octave script to check c port of mancyfsk/fmfsk against the fmfsk.m
+%
+#{
+
+ FMFSK Modem automated test instructions:
+
+ 1. Use cmake to build in debug mode to ensure unittest/tfsk is built:
+
+ $ cd ~/codec2
+ $ rm -Rf build_linux && mkdir build_linux
+ $ cd build_linux
+ $ cmake -DCMAKE_BUILD_TYPE=Debug ..
+ $ make
+
+ 2 - Change tfsk_location below if required
+ 3 - Ensure Octave packages signal and parallel are installed
+ 4 - Start Octave and run tfsk.m. It will perform all tests automatically
+
+#}
+
+%tfsk executable path/file
+global tfsk_location = '../build_linux/unittest/tfmfsk';
+
+%Set to 1 for verbose printouts
+global print_verbose = 0;
+
+
+
+fmfsk
+pkg load signal;
+pkg load parallel;
+graphics_toolkit('gnuplot');
+
+
+global mod_pass_fail_maxdiff = 1e-3/5000;
+
+function mod = fmfsk_mod_c(Fs,Rs,bits)
+ global tfsk_location;
+ %command to be run by system to launch the modulator
+ command = sprintf('%s M %d %d fsk_mod_ut_bitvec fsk_mod_ut_modvec fmfsk_mod_ut_log.txt',tfsk_location,Fs,Rs);
+ %save input bits into a file
+ bitvecfile = fopen('fsk_mod_ut_bitvec','wb+');
+ fwrite(bitvecfile,bits,'uint8');
+ fclose(bitvecfile);
+
+ %run the modulator
+ system(command);
+
+ modvecfile = fopen('fsk_mod_ut_modvec','rb');
+ mod = fread(modvecfile,'single');
+ fclose(modvecfile);
+
+endfunction
+
+
+%Compare 2 vectors, fail if they are not close enough
+function pass = vcompare(vc,voct,vname,tname,tol,pnum)
+ global print_verbose;
+
+ %Get delta of vectors
+ dvec = abs(abs(vc)-abs(voct));
+
+ %Normalize difference
+ dvec = dvec ./ abs(max(abs(voct))+1e-8);
+
+ maxdvec = abs(max(dvec));
+ pass = maxdvec<tol;
+ if print_verbose == 1
+ printf(' Comparing vectors %s in test %s. Diff is %f\n',vname,tname,maxdvec);
+ end
+
+ if pass == 0
+ printf('\n*** vcompare failed %s in test %s. Diff: %f Tol: %f\n\n',vname,tname,maxdvec,tol);
+
+ titlestr = sprintf('Diff between C and Octave of %s for %s',vname,tname)
+ figure(10+pnum*2)
+ plot(abs(dvec))
+ title(titlestr)
+
+ figure(11+pnum*2)
+ plot((1:length(vc)),abs(vc),(1:length(voct)),abs(voct))
+
+ end
+
+endfunction
+
+function test_stats = fmfsk_demod_xt(Fs,Rs,mod,tname,M=2)
+ global tfsk_location;
+
+ %Name of executable containing the modulator
+ modvecfilename = sprintf('fmfsk_demod_ut_modvec_%d',getpid());
+ bitvecfilename = sprintf('fmfsk_demod_ut_bitvec_%d',getpid());
+ tvecfilename = sprintf('fmfsk_demod_ut_tracevec_%d.txt',getpid());
+
+ %command to be run by system to launch the demod
+ command = sprintf('%s D %d %d %s %s %s',tfsk_location,Fs,Rs,modvecfilename,bitvecfilename,tvecfilename);
+
+ %save modulated input into a file
+ modvecfile = fopen(modvecfilename,'wb+');
+ fwrite(modvecfile,mod,'single');
+ fclose(modvecfile);
+
+ %run the modulator
+ system(command);
+
+ bitvecfile = fopen(bitvecfilename,'rb');
+ bits = fread(bitvecfile,'uint8');
+ fclose(bitvecfile);
+ bits = bits!=0;
+
+ %Load test vec dump
+ load(tvecfilename);
+
+ %Clean up files
+ delete(bitvecfilename);
+ delete(modvecfilename);
+ delete(tvecfilename);
+
+ o_norm_rx_timing = [];
+ o_symsamp = [];
+ o_rx_filt = [];
+
+ %Run octave demod, dump some test vectors
+ states = fmfsk_init(Fs,Rs);
+ Ts = states.Ts;
+ modin = mod;
+ obits = [];
+ while length(modin)>=states.nin
+ ninold = states.nin;
+ [bitbuf,states] = fmfsk_demod(states, modin(1:states.nin));
+ modin=modin(ninold+1:length(modin));
+ obits = [obits bitbuf];
+
+ o_norm_rx_timing = [o_norm_rx_timing states.norm_rx_timing];
+ o_symsamp = [o_symsamp states.symsamp];
+ o_rx_filt = [o_rx_filt states.rx_filt];
+
+ end
+
+ close all
+ pass = 1;
+
+ % One part-per-thousand allowed on important parameters
+
+ pass = vcompare(t_rx_filt,o_rx_filt,'rx filt',tname,.001,8) && pass;
+ pass = vcompare(t_norm_rx_timing,o_norm_rx_timing,'norm rx timing',tname,.001,9) && pass;
+ pass = vcompare(t_symsamp,o_symsamp,'symsamp',tname,.001,10) && pass;
+
+ assert(pass);
+ diffpass = sum(xor(obits,bits'))<4;
+ diffbits = sum(xor(obits,bits'));
+
+
+ if diffpass==0
+ printf('\n***bitcompare test failed test %s diff %d\n\n',tname,sum(xor(obits,bits')))
+ figure(15)
+ plot(xor(obits,bits'))
+ title(sprintf('Bitcompare failure test %s',tname))
+ end
+
+ pass = pass && diffpass;
+
+
+ test_stats.pass = pass;
+ test_stats.diff = sum(xor(obits,bits'));
+ test_stats.cbits = bits';
+ test_stats.obits = obits;
+
+endfunction
+
+function [dmod,cmod,omod,pass] = fmfsk_mod_test(Fs,Rs,bits,tname,M=2)
+ global mod_pass_fail_maxdiff;
+ %Run the C modulator
+ cmod = fmfsk_mod_c(Fs,Rs,bits);
+ %Set up and run the octave modulator
+ states.M = M;
+ states = fmfsk_init(Fs,Rs);
+
+
+ omod = fmfsk_mod(states,bits)';
+
+ dmod = cmod-omod;
+ pass = max(dmod)<(mod_pass_fail_maxdiff*length(dmod));
+ if !pass
+ printf('Mod failed test %s!\n',tname);
+ end
+endfunction
+
+% Random bit modulator test
+% Pass random bits through the modulators and compare
+function pass = test_mod_fdvbcfg_randbits
+ rand('state',1);
+ randn('state',1);
+ bits = rand(1,19200)>.5;
+ [dmod,cmod,omod,pass] = fmfsk_mod_test(48000,2400,bits,"mod fdvbcfg randbits");
+
+ if(!pass)
+ figure(1)
+ plot(dmod)
+ title("Difference between octave and C mod impl");
+ end
+
+endfunction
+
+% run_sim copypasted from fsk_horus.m
+% simulation of tx and rx side, add noise, channel impairments ----------------------
+
+function stats = tfmfsk_run_sim(EbNodB,timing_offset=0,de=0,of=0,hpf=0,df=0,M=2)
+ global print_verbose;
+ test_frame_mode = 2;
+ frames = 70;
+ %EbNodB = 3;
+ %timing_offset = 0.0; % see resample() for clock offset below
+ %fading = 0; % modulates tx power at 2Hz with 20dB fade depth,
+ % to simulate balloon rotating at end of mission
+
+ more off
+ rand('state',1);
+ randn('state',1);
+
+ Fs = 48000;
+ Rbit = 2400;
+
+ % ----------------------------------------------------------------------
+
+ fm_states.pre_emp = 0;
+ fm_states.de_emp = de;
+ fm_states.Ts = Fs/(Rbit*2);
+ fm_states.Fs = Fs;
+ fm_states.fc = Fs/4;
+ fm_states.fm_max = 3E3;
+ fm_states.fd = 5E3;
+ fm_states.output_filter = of;
+ fm_states = analog_fm_init(fm_states);
+
+ % ----------------------------------------------------------------------
+
+ states = fmfsk_init(Fs,Rbit);
+
+ states.verbose = 0x1;
+ Rs = states.Rs;
+ nsym = states.nsym;
+ Fs = states.Fs;
+ nbit = states.nbit;
+
+ EbNo = 10^(EbNodB/10);
+ variance = states.Fs/(states.Rb*EbNo);
+
+ % set up tx signal with payload bits based on test mode
+
+ if test_frame_mode == 1
+ % test frame of bits, which we repeat for convenience when BER testing
+ test_frame = round(rand(1, states.nbit));
+ tx_bits = [];
+ for i=1:frames+1
+ tx_bits = [tx_bits test_frame];
+ end
+ end
+ if test_frame_mode == 2
+ % random bits, just to make sure sync algs work on random data
+ tx_bits = round(rand(1, states.nbit*(frames+1)));
+ end
+ if test_frame_mode == 3
+ % repeating sequence of all symbols
+ % great for initial test of demod if nothing else works,
+ % look for this pattern in rx_bits
+
+ % ...10101...
+ tx_bits = zeros(1, states.nbit*(frames+1));
+ tx_bits(1:2:length(tx_bits)) = 1;
+
+ end
+
+ [b, a] = cheby1(4, 1, 300/Fs, 'high'); % 300Hz HPF to simulate FM radios
+
+ tx_pmod = fmfsk_mod(states, tx_bits);
+
+ tx = analog_fm_mod(fm_states, tx_pmod);
+
+ if(timing_offset>0)
+ tx = resample(tx, 2000, 1999); % simulated 1000ppm sample clock offset
+ end
+
+ %Add frequency drift
+ fdrift = df/Fs;
+ fshift = 2*pi*fdrift*(1:length(tx));
+ fshift = exp(j*(fshift.^2));
+ tx = tx.*fshift;
+ noise = sqrt(variance)*randn(length(tx),1);
+ rx = tx + noise';
+
+ %Demod by analog fm
+ rx = analog_fm_demod(fm_states, rx);
+
+ %High-pass filter to simulate the FM radios
+ if hpf>0
+ rx = filter(b,a,rx);
+ end
+
+ timing_offset_samples = round(timing_offset*states.Ts);
+ st = 1 + timing_offset_samples;
+ rx_bits_buf = zeros(1,2*nbit);
+
+ test_name = sprintf("tfmfsk run sim EbNodB:%d frames:%d timing_offset:%d df:%d",EbNodB,frames,timing_offset,df);
+ tstats = fmfsk_demod_xt(Fs,Rbit,rx',test_name,M);
+
+ pass = tstats.pass;
+ obits = tstats.obits;
+ cbits = tstats.cbits;
+
+ % Figure out BER of octave and C modems
+ bitcnt = length(tx_bits);
+ rx_bits = obits;
+ ber = 1;
+ ox = 1;
+ for offset = (1:400)
+ nerr = sum(xor(rx_bits(offset:length(rx_bits)),tx_bits(1:length(rx_bits)+1-offset)));
+ bern = nerr/(bitcnt-offset);
+ if(bern < ber)
+ ox = offset;
+ best_nerr = nerr;
+ end
+ ber = min([ber bern]);
+ end
+ offset = ox;
+ bero = ber;
+ ber = 1;
+ rx_bits = cbits;
+ ox = 1;
+ for offset = (1:400)
+ nerr = sum(xor(rx_bits(offset:length(rx_bits)),tx_bits(1:length(rx_bits)+1-offset)));
+ bern = nerr/(bitcnt-offset);
+ if(bern < ber)
+ ox = offset;
+ best_nerr = nerr;
+ end
+ ber = min([ber bern]);
+ end
+ offset = ox;
+ berc = ber;
+
+ if print_verbose == 1
+ printf("C BER %f in test %s\n",berc,test_name);
+ printf("Oct BER %f in test %s\n",bero,test_name);
+ end
+
+ stats.berc = berc;
+ stats.bero = bero;
+ stats.name = test_name;
+ % non-coherent BER theory calculation
+ % It was complicated, so I broke it up
+
+ ms = 2;
+ ns = (1:ms-1);
+ as = (-1).^(ns+1);
+ bs = (as./(ns+1));
+
+ cs = ((ms-1)./ns);
+
+ ds = ns.*log2(ms);
+ es = ns+1;
+ fs = exp( -(ds./es)*EbNo );
+
+ thrncoh = ((ms/2)/(ms-1)) * sum(bs.*((ms-1)./ns).*exp( -(ds./es)*EbNo ));
+
+ stats.thrncoh = thrncoh;
+ stats.pass = pass;
+ endfunction
+
+
+function pass = ebno_battery_test(timing_offset,drift,hpf,deemp,outfilt)
+ global print_verbose;
+ %Range of EbNodB over which to test
+ ebnodbrange = (8:2:20);
+ ebnodbs = length(ebnodbrange);
+
+ %Replication of other parameters for parcellfun
+ timingv = repmat(timing_offset ,1,ebnodbs);
+ driftv = repmat(drift ,1,ebnodbs);
+ hpfv = repmat(hpf ,1,ebnodbs);
+ deempv = repmat(deemp ,1,ebnodbs);
+ outfv = repmat(outfilt ,1,ebnodbs);
+
+ statv = pararrayfun(floor(.75*nproc()),@tfmfsk_run_sim,ebnodbrange,timingv,deempv,outfv,hpfv,driftv);
+ %statv = arrayfun(@tfsk_run_sim,modev,ebnodbrange,timingv,fadingv,dfv,dav,mv);
+
+ passv = zeros(1,length(statv));
+ for ii=(1:length(statv))
+ passv(ii)=statv(ii).pass;
+ if statv(ii).pass
+ printf("Test %s passed\n",statv(ii).name);
+ else
+ printf("Test %s failed\n",statv(ii).name);
+ end
+ end
+
+ %All pass flags are '1'
+ pass = sum(passv)>=length(passv);
+ %and no tests died
+ pass = pass && length(passv)==ebnodbs;
+ passv;
+ assert(pass)
+endfunction
+
+%Test with and without sample clock offset
+function pass = test_timing_var(drift,hpf,deemp,outfilt)
+ pass = ebno_battery_test(1,drift,hpf,deemp,outfilt)
+ assert(pass)
+ pass = ebno_battery_test(0,drift,hpf,deemp,outfilt)
+ assert(pass)
+endfunction
+
+%Test with and without 1 Hz/S freq drift
+function pass = test_drift_var(hpf,deemp,outfilt)
+ pass = test_timing_var(1,hpf,deemp,outfilt)
+ assert(pass)
+ pass = pass && test_timing_var(0,hpf,deemp,outfilt)
+ assert(pass)
+endfunction
+
+function pass = test_fmfsk_battery()
+ pass = test_mod_fdvbcfg_randbits;
+ assert(pass)
+ pass = pass && test_drift_var(1,1,1);
+ assert(pass)
+ if pass
+ printf("***** All tests passed! *****\n");
+ end
+endfunction
+
+function plot_fmfsk_bers(M=2)
+ %Range of EbNodB over which to test
+ ebnodbrange = (8:14);
+ ebnodbs = length(ebnodbrange);
+
+ %Replication of other parameters for parcellfun
+ %Turn on all of the impairments
+ timingv = repmat(1 ,1,ebnodbs);
+ driftv = repmat(1 ,1,ebnodbs);
+ hpfv = repmat(1 ,1,ebnodbs);
+ deempv = repmat(1 ,1,ebnodbs);
+ outfv = repmat(1 ,1,ebnodbs);
+
+ statv = pararrayfun(nproc(),@tfmfsk_run_sim,ebnodbrange,timingv,deempv,outfv,hpfv,driftv);
+ %statv = arrayfun(@tfsk_run_sim,modev,ebnodbrange,timingv,fadingv,dfv,dav,Mv);
+
+ for ii = (1:length(statv))
+ stat = statv(ii);
+ berc(ii)=stat.berc;
+ bero(ii)=stat.bero;
+ berinc(ii)=stat.thrncoh;
+ end
+ clf;
+ figure(M)
+
+ semilogy(ebnodbrange, berinc,sprintf('r;2FSK non-coherent theory;',M))
+ hold on;
+ semilogy(ebnodbrange, bero ,sprintf('g;Octave ME-FM-FSK Demod;',M))
+ semilogy(ebnodbrange, berc,sprintf('v;C ME-FM-FSK Demod;',M))
+ hold off;
+ grid("minor");
+ axis([min(ebnodbrange) max(ebnodbrange) 1E-5 1])
+ legend("boxoff");
+ xlabel("Eb/No (dB)");
+ ylabel("Bit Error Rate (BER)")
+
+endfunction
+
+xpass = test_fmfsk_battery
+plot_fmfsk_bers(2)
+
+if xpass
+ printf("***** All tests passed! *****\n");
+else
+ printf("***** Some test failed! Look back through output to find failed test *****\n");
+end
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