+++ /dev/null
-#!/usr/bin/env python
-
-from gnuradio import gr
-from gnuradio import audio
-from gnuradio import trellis
-from gnuradio import eng_notation
-import math
-import sys
-import fsm_utils
-
-
-def make_rx(fg,fo,fi,dimensionality,tot_constellation,K,interleaver,IT,Es,N0,type):
- metrics_in = trellis.metrics_f(fi.O(),dimensionality,tot_constellation,trellis.TRELLIS_EUCLIDEAN) # data preprocessing to generate metrics for innner SISO
- scale = gr.multiply_const_ff(1.0/N0)
- gnd = gr.vector_source_f([0],True);
-
- inter=[]
- deinter=[]
- siso_in=[]
- siso_out=[]
-
- # generate all blocks
- for it in range(IT):
- inter.append( trellis.permutation(interleaver.K(),interleaver.INTER(),fi.I(),gr.sizeof_float) )
- siso_in.append( trellis.siso_f(fi,K,0,-1,True,False,type) )
- deinter.append( trellis.permutation(interleaver.K(),interleaver.DEINTER(),fi.I(),gr.sizeof_float) )
- if it < IT-1:
- siso_out.append( trellis.siso_f(fo,K,0,-1,False,True,type) )
- else:
- siso_out.append( trellis.viterbi_s(fo,K,0,-1) ) # no soft outputs needed
-
- # connect first stage
- fg.connect (gnd,inter[0])
- fg.connect (metrics_in,scale)
- fg.connect (scale,(siso_in[0],1))
-
- # connect the rest
- for it in range(IT):
- if it < IT-1:
- fg.connect (metrics_in,(siso_in[it+1],1))
- fg.connect (siso_in[it],deinter[it],(siso_out[it],1))
- fg.connect (gnd,(siso_out[it],0))
- fg.connect (siso_out[it],inter[it+1])
- fg.connect (inter[it],(siso_in[it],0))
- else:
- fg.connect (siso_in[it],deinter[it],siso_out[it])
- fg.connect (inter[it],(siso_in[it],0))
-
- return (metrics_in,siso_out[IT-1])
-
-
-def run_test (fo,fi,interleaver,Kb,bitspersymbol,K,dimensionality,tot_constellation,Es,N0,IT,seed):
- fg = gr.flow_graph ()
-
- # TX
- src = gr.lfsr_32k_source_s()
- src_head = gr.head (gr.sizeof_short,Kb/16) # packet size in shorts
- s2fsmi = gr.packed_to_unpacked_ss(bitspersymbol,gr.GR_MSB_FIRST) # unpack shorts to symbols compatible with the iouter FSM input cardinality
- enc_out = trellis.encoder_ss(fo,0) # initial state = 0
- inter = trellis.permutation(interleaver.K(),interleaver.INTER(),1,gr.sizeof_short)
- enc_in = trellis.encoder_ss(fi,0) # initial state = 0
- # essentially here we implement the combination of modulation and channel as a memoryless modulation (the memory induced by the channel is hidden in the innner FSM)
- mod = gr.chunks_to_symbols_sf(tot_constellation,dimensionality)
-
- # CHANNEL
- add = gr.add_ff()
- noise = gr.noise_source_f(gr.GR_GAUSSIAN,math.sqrt(N0/2),seed)
-
- # RX
- (head,tail) = make_rx(fg,fo,fi,dimensionality,tot_constellation,K,interleaver,IT,Es,N0,trellis.TRELLIS_MIN_SUM)
- fsmi2s = gr.unpacked_to_packed_ss(bitspersymbol,gr.GR_MSB_FIRST) # pack FSM input symbols to shorts
- dst = gr.check_lfsr_32k_s();
-
- fg.connect (src,src_head,s2fsmi,enc_out,inter,enc_in,mod)
- fg.connect (mod,(add,0))
- fg.connect (noise,(add,1))
- fg.connect (add,head)
- fg.connect (tail,fsmi2s,dst)
-
- fg.run()
-
- ntotal = dst.ntotal ()
- nright = dst.nright ()
- runlength = dst.runlength ()
- #print ntotal,nright,runlength
-
- return (ntotal,ntotal-nright)
-
-
-
-
-def main(args):
- nargs = len (args)
- if nargs == 3:
- fname_out=args[0]
- esn0_db=float(args[1])
- rep=int(args[2])
- else:
- sys.stderr.write ('usage: test_turbo_equalization.py fsm_name_out Es/No_db repetitions\n')
- sys.exit (1)
-
- # system parameters
- Kb=64*16 # packet size in bits (multiple of 16)
- modulation = fsm_utils.pam4 # see fsm_utlis.py for available predefined modulations
- channel = fsm_utils.c_channel # see fsm_utlis.py for available predefined test channels
- fo=trellis.fsm(fname_out) # get the outer FSM specification from a file
- fi=trellis.fsm(len(modulation[1]),len(channel)) # generate the FSM automatically
- if fo.O() != fi.I():
- sys.stderr.write ('Incompatible cardinality between outer and inner FSM.\n')
- sys.exit (1)
- bitspersymbol = int(round(math.log(fo.I())/math.log(2))) # bits per FSM input symbol
- K=Kb/bitspersymbol # packet size in trellis steps
- interleaver=trellis.interleaver(K,666) # construct a random interleaver
- tot_channel = fsm_utils.make_isi_lookup(modulation,channel,True) # generate the lookup table (normalize energy to 1)
- dimensionality = tot_channel[0]
- tot_constellation = tot_channel[1]
- if len(tot_constellation)/dimensionality != fi.O():
- sys.stderr.write ('Incompatible FSM output cardinality and lookup table size.\n')
- sys.exit (1)
- N0=pow(10.0,-esn0_db/10.0); # noise variance
- IT = 3 # number of turbo iterations
-
- 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(fo,fi,interleaver,Kb,bitspersymbol,K,dimensionality,tot_constellation,1,N0,IT,-long(666+i)) # 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)%10==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 (sys.argv[1:])
-
projects / debian / gnuradio / blobdiff