diff options
Diffstat (limited to 'gr-trellis/src/examples/python/test_tcm_parallel.py')
| -rwxr-xr-x | gr-trellis/src/examples/python/test_tcm_parallel.py | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/gr-trellis/src/examples/python/test_tcm_parallel.py b/gr-trellis/src/examples/python/test_tcm_parallel.py new file mode 100755 index 000000000..2b722c09e --- /dev/null +++ b/gr-trellis/src/examples/python/test_tcm_parallel.py @@ -0,0 +1,113 @@ +#!/usr/bin/env python + +from gnuradio import gr +from gnuradio import trellis, digital +from gnuradio import eng_notation +import math +import sys +import fsm_utils +from gnuradio.eng_option import eng_option +from optparse import OptionParser + + +def run_test (f,Kb,bitspersymbol,K,dimensionality,constellation,N0,seed,P): + tb = gr.top_block () + + # TX + src = gr.lfsr_32k_source_s() + src_head = gr.head (gr.sizeof_short,Kb/16*P) # packet size in shorts + s2fsmi=gr.packed_to_unpacked_ss(bitspersymbol,gr.GR_MSB_FIRST) # unpack shorts to symbols compatible with the FSM input cardinality + s2p = gr.stream_to_streams(gr.sizeof_short,P) # serial to parallel + enc = trellis.encoder_ss(f,0) # initiali state = 0 + mod = gr.chunks_to_symbols_sf(constellation,dimensionality) + + # CHANNEL + add=[] + noise=[] + for i in range(P): + add.append(gr.add_ff()) + noise.append(gr.noise_source_f(gr.GR_GAUSSIAN,math.sqrt(N0/2),seed)) + + # RX + metrics = trellis.metrics_f(f.O(),dimensionality,constellation,digital.TRELLIS_EUCLIDEAN) # data preprocessing to generate metrics for Viterbi + va = trellis.viterbi_s(f,K,0,-1) # Put -1 if the Initial/Final states are not set. + p2s = gr.streams_to_stream(gr.sizeof_short,P) # parallel to serial + fsmi2s=gr.unpacked_to_packed_ss(bitspersymbol,gr.GR_MSB_FIRST) # pack FSM input symbols to shorts + dst = gr.check_lfsr_32k_s() + + tb.connect (src,src_head,s2fsmi,s2p) + for i in range(P): + tb.connect ((s2p,i),(enc,i),(mod,i)) + tb.connect ((mod,i),(add[i],0)) + tb.connect (noise[i],(add[i],1)) + tb.connect (add[i],(metrics,i)) + tb.connect ((metrics,i),(va,i),(p2s,i)) + tb.connect (p2s,fsmi2s,dst) + + + tb.run() + + # A bit of cheating: run the program once and print the + # final encoder state. + # Then put it as the last argument in the viterbi block + #print "final state = " , enc.ST() + + ntotal = dst.ntotal () + nright = dst.nright () + runlength = dst.runlength () + + return (ntotal,ntotal-nright) + + + +def main(): + parser = OptionParser(option_class=eng_option) + parser.add_option("-f", "--fsm_file", type="string", default="fsm_files/awgn1o2_4.fsm", help="Filename containing the fsm specification, e.g. -f fsm_files/awgn1o2_4.fsm (default=fsm_files/awgn1o2_4.fsm)") + parser.add_option("-e", "--esn0", type="eng_float", default=10.0, help="Symbol energy to noise PSD level ratio in dB, e.g., -e 10.0 (default=10.0)") + parser.add_option("-r", "--repetitions", type="int", default=100, help="Number of packets to be generated for the simulation, e.g., -r 100 (default=100)") + + (options, args) = parser.parse_args () + if len(args) != 0: + parser.print_help() + raise SystemExit, 1 + + fname=options.fsm_file + esn0_db=float(options.esn0) + rep=int(options.repetitions) + + # system parameters + f=trellis.fsm(fname) # get the FSM specification from a file + P=4 # how many parallel streams? + Kb=1024*16 # packet size in bits (make it multiple of 16 so it can be packed in a short) + bitspersymbol = int(round(math.log(f.I())/math.log(2))) # bits per FSM input symbol + K=Kb/bitspersymbol # packet size in trellis steps + modulation = fsm_utils.psk4 # see fsm_utlis.py for available predefined modulations + dimensionality = modulation[0] + constellation = modulation[1] + if len(constellation)/dimensionality != f.O(): + sys.stderr.write ('Incompatible FSM output cardinality and modulation size.\n') + sys.exit (1) + # calculate average symbol energy + Es = 0 + for i in range(len(constellation)): + Es = Es + constellation[i]**2 + Es = Es / (len(constellation)/dimensionality) + N0=Es/pow(10.0,esn0_db/10.0); # calculate noise variance + + tot_s=0 # total number of transmitted shorts + terr_s=0 # total number of shorts in error + terr_p=0 # total number of packets in error + for i in range(rep): + (s,e)=run_test(f,Kb,bitspersymbol,K,dimensionality,constellation,N0,-long(666+i),P) # run experiment with different seed to get different noise realizations + tot_s=tot_s+s + terr_s=terr_s+e + terr_p=terr_p+(terr_s!=0) + if ((i+1)%100==0) : # display progress + print i+1,terr_p, '%.2e' % ((1.0*terr_p)/(i+1)),tot_s,terr_s, '%.2e' % ((1.0*terr_s)/tot_s) + # estimate of the (short or bit) error rate + print rep,terr_p, '%.2e' % ((1.0*terr_p)/(i+1)),tot_s,terr_s, '%.2e' % ((1.0*terr_s)/tot_s) + + +if __name__ == '__main__': + main() + |