diff options
Diffstat (limited to 'gr-trellis/docs/test_tcm.py')
| -rw-r--r-- | gr-trellis/docs/test_tcm.py | 105 |
1 files changed, 59 insertions, 46 deletions
diff --git a/gr-trellis/docs/test_tcm.py b/gr-trellis/docs/test_tcm.py index f9442dbc9f..65df9a2dbe 100644 --- a/gr-trellis/docs/test_tcm.py +++ b/gr-trellis/docs/test_tcm.py @@ -15,84 +15,97 @@ except ImportError: sys.stderr.write("Error: Program requires gr-analog.\n") sys.exit(1) -def run_test (f,Kb,bitspersymbol,K,dimensionality,constellation,N0,seed): - tb = gr.top_block () + +def run_test(f, Kb, bitspersymbol, K, dimensionality, constellation, N0, seed): + tb = gr.top_block() # TX src = blocks.lfsr_32k_source_s() - src_head = blocks.head (gr.sizeof_short,Kb / 16) # packet size in shorts - s2fsmi = blocks.packed_to_unpacked_ss(bitspersymbol,gr.GR_MSB_FIRST) # unpack shorts to symbols compatible with the FSM input cardinality - enc = trellis.encoder_ss(f,0) # initial state = 0 - mod = digital.chunks_to_symbols_sf(constellation,dimensionality) + src_head = blocks.head(gr.sizeof_short, Kb / 16) # packet size in shorts + # unpack shorts to symbols compatible with the FSM input cardinality + s2fsmi = blocks.packed_to_unpacked_ss(bitspersymbol, gr.GR_MSB_FIRST) + enc = trellis.encoder_ss(f, 0) # initial state = 0 + mod = digital.chunks_to_symbols_sf(constellation, dimensionality) # CHANNEL add = blocks.add_ff() - noise = analog.noise_source_f(analog.GR_GAUSSIAN,math.sqrt(N0 / 2),seed) + noise = analog.noise_source_f(analog.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. - fsmi2s = blocks.unpacked_to_packed_ss(bitspersymbol,gr.GR_MSB_FIRST) # pack FSM input symbols to shorts - dst = blocks.check_lfsr_32k_s(); - - tb.connect (src,src_head,s2fsmi,enc,mod) - tb.connect (mod,(add,0)) - tb.connect (noise,(add,1)) - tb.connect (add,metrics) - tb.connect (metrics,va,fsmi2s,dst) + # data preprocessing to generate metrics for Viterbi + metrics = trellis.metrics_f( + f.O(), dimensionality, constellation, digital.TRELLIS_EUCLIDEAN) + # Put -1 if the Initial/Final states are not set. + va = trellis.viterbi_s(f, K, 0, -1) + fsmi2s = blocks.unpacked_to_packed_ss( + bitspersymbol, gr.GR_MSB_FIRST) # pack FSM input symbols to shorts + dst = blocks.check_lfsr_32k_s() + + tb.connect(src, src_head, s2fsmi, enc, mod) + tb.connect(mod, (add, 0)) + tb.connect(noise, (add, 1)) + tb.connect(add, metrics) + tb.connect(metrics, va, 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() + # print "final state = " , enc.ST() - ntotal = dst.ntotal () - nright = dst.nright () - runlength = dst.runlength () - return (ntotal,ntotal-nright) + ntotal = dst.ntotal() + nright = dst.nright() + runlength = dst.runlength() + return (ntotal, ntotal - nright) def main(args): - nargs = len (args) + nargs = len(args) if nargs == 3: - fname=args[0] - esn0_db=float(args[1]) # Es/No in dB - rep=int(args[2]) # number of times the experiment is run to collect enough errors + fname = args[0] + esn0_db = float(args[1]) # Es/No in dB + # number of times the experiment is run to collect enough errors + rep = int(args[2]) else: - sys.stderr.write ('usage: test_tcm.py fsm_fname Es/No_db repetitions\n') - sys.exit (1) + sys.stderr.write( + 'usage: test_tcm.py fsm_fname Es/No_db repetitions\n') + sys.exit(1) # system parameters - f=trellis.fsm(fname) # get the FSM specification from a file - 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 + f = trellis.fsm(fname) # get the FSM specification from a file + # packet size in bits (make it multiple of 16 so it can be packed in a short) + Kb = 1024 * 16 + # bits per FSM input symbol + bitspersymbol = int(round(math.log(f.I()) / math.log(2))) + 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) + 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); # noise variance + Es = Es / (len(constellation) // dimensionality) + N0 = Es / pow(10.0, esn0_db / 10.0) # noise variance - tot_s=0 - terr_s=0 + tot_s = 0 + terr_s = 0 for i in range(rep): - (s,e)=run_test(f,Kb,bitspersymbol,K,dimensionality,constellation,N0,-int(666+i)) # run experiment with different seed to get different noise realizations - tot_s=tot_s+s - terr_s=terr_s+e - if (i%100==0): - print(i,s,e,tot_s,terr_s, '%e' % ((1.0*terr_s) / tot_s)) + # run experiment with different seed to get different noise realizations + (s, e) = run_test(f, Kb, bitspersymbol, K, + dimensionality, constellation, N0, -int(666 + i)) + tot_s = tot_s + s + terr_s = terr_s + e + if (i % 100 == 0): + print(i, s, e, tot_s, terr_s, '%e' % ((1.0 * terr_s) / tot_s)) # estimate of the (short) error rate - print(tot_s,terr_s, '%e' % ((1.0*terr_s) / tot_s)) + print(tot_s, terr_s, '%e' % ((1.0 * terr_s) / tot_s)) if __name__ == '__main__': - main (sys.argv[1:]) + main(sys.argv[1:]) |