diff options
Diffstat (limited to 'gnuradio-examples/python')
3 files changed, 22 insertions, 15 deletions
diff --git a/gnuradio-examples/python/channel-coding/README b/gnuradio-examples/python/channel-coding/README index 2be8c6ba1..7f25b697b 100644 --- a/gnuradio-examples/python/channel-coding/README +++ b/gnuradio-examples/python/channel-coding/README @@ -18,8 +18,13 @@ If you just want to see what these programs do, run each of the following: ./test_sccc_soft.py fsm_files/awgn1o2_4.fsm fsm_files/awgn1o2_4_msb.fsm 8.0 100 ./test_sccc_turbo.py fsm_files/awgn1o2_4.fsm fsm_files/awgn1o2_4_msb.fsm 5.0 100 +./test_viterbi_equalization.py 12.0 100 +./test_viterbi_equalization1.py 12.0 100 + + In your terminal you will see something like this: + $ ./test_tcm.py fsm_files/awgn1o2_4.fsm 6.0 1000 100 98 9.80e-01 102400 9 8.79e-05 200 198 9.90e-01 204800 20 9.77e-05 @@ -36,11 +41,11 @@ $ ./test_tcm.py fsm_files/awgn1o2_4.fsm 6.0 1000 which gives you information about the: number of transmitted packets number of packets in error -iestimated packet error rate -number of transmitted shorts -number of shorts in error -estimated (short) error rate - -1.10e-03 is the error rate estimate by sending 1000 packets of -1024 shorts each, using an 1/2 4-state convolutional code and QPSK -modulation through an AWGN with Es/N0 = 6.0 dB +estimated packet error rate +number of transmitted shorts (or symbols, or bits, depending on the specific program) +number of shorts (or symbols, or bits) in error +estimated short (or symbol, or bit) error rate + +for instance, the final number 1.10e-03 is the error rate estimate by sending 1000 +packets of 1024 shorts each, using an 1/2 4-state convolutional code +and QPSK modulation through an AWGN with Es/N0 = 6.0 dB diff --git a/gnuradio-examples/python/channel-coding/test_tcm_combined.py b/gnuradio-examples/python/channel-coding/test_tcm_combined.py index 37f38ef1a..e286f88f6 100755 --- a/gnuradio-examples/python/channel-coding/test_tcm_combined.py +++ b/gnuradio-examples/python/channel-coding/test_tcm_combined.py @@ -13,7 +13,7 @@ def run_test (f,Kb,bitspersymbol,K,dimensionality,constellation,N0,seed): # TX src = gr.lfsr_32k_source_s() - src_head = gr.head (gr.sizeof_short,K/16) # packet size in shorts + 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 FSM input cardinality enc = trellis.encoder_ss(f,0) # initial state = 0 mod = gr.chunks_to_symbols_sf(constellation,dimensionality) @@ -25,7 +25,7 @@ def run_test (f,Kb,bitspersymbol,K,dimensionality,constellation,N0,seed): # RX - va = trellis.viterbi_combined_s(f,dimensionality,constellation,K/bitspersymbol,0,-1,trellis.TRELLIS_EUCLIDEAN) # Put -1 if the Initial/Final states are not set. + va = trellis.viterbi_combined_s(f,K,0,-1,dimensionality,constellation,trellis.TRELLIS_EUCLIDEAN) # Put -1 if the Initial/Final states are not set. fsmi2s = gr.unpacked_to_packed_ss(bitspersymbol,gr.GR_MSB_FIRST) # pack FSM input symbols to shorts dst = gr.check_lfsr_32k_s(); diff --git a/gnuradio-examples/python/channel-coding/test_viterbi_equalization1.py b/gnuradio-examples/python/channel-coding/test_viterbi_equalization1.py index 133e550db..8e197cae9 100755 --- a/gnuradio-examples/python/channel-coding/test_viterbi_equalization1.py +++ b/gnuradio-examples/python/channel-coding/test_viterbi_equalization1.py @@ -16,6 +16,7 @@ def run_test (f,Kb,bitspersymbol,K,channel,modulation,dimensionality,tot_constel # TX # this for loop is TOO slow in python!!! packet = [0]*(K+2*L) + random.seed(seed) for i in range(len(packet)): packet[i] = random.randint(0, 2**bitspersymbol - 1) # random symbols for i in range(L): # first/last L symbols set to 0 @@ -30,9 +31,10 @@ def run_test (f,Kb,bitspersymbol,K,channel,modulation,dimensionality,tot_constel noise = gr.noise_source_f(gr.GR_GAUSSIAN,math.sqrt(N0/2),seed) # RX + skip = gr.skiphead(gr.sizeof_float, L) # skip the first L samples since you know they are coming from the L zero symbols #metrics = trellis.metrics_f(f.O(),dimensionality,tot_constellation,trellis.TRELLIS_EUCLIDEAN) # data preprocessing to generate metrics for Viterbi - #va = trellis.viterbi_s(f,K+2*L,-1,0) # Put -1 if the Initial/Final states are not set. Better if we could skip the first L symbols and start with a 0 state... don't know how to "skip" samples in gnuradio - va = trellis.viterbi_combined_s(f,dimensionality,tot_constellation,K+2*L,-1,0,trellis.TRELLIS_EUCLIDEAN) # using viterbi_combined_s instead of metrics_f/viterbi_s allows larger packet lengths because metrics_f is complaining for not being able to allocate large buffers. This is due to the large f.O() in this application... + #va = trellis.viterbi_s(f,K+L,-1,0) # Put -1 if the Initial/Final states are not set. + va = trellis.viterbi_combined_s(f,K+L,0,0,dimensionality,tot_constellation,trellis.TRELLIS_EUCLIDEAN) # using viterbi_combined_s instead of metrics_f/viterbi_s allows larger packet lengths because metrics_f is complaining for not being able to allocate large buffers. This is due to the large f.O() in this application... dst = gr.vector_sink_s() fg.connect (src,mod) @@ -40,15 +42,15 @@ def run_test (f,Kb,bitspersymbol,K,channel,modulation,dimensionality,tot_constel fg.connect (noise,(add,1)) #fg.connect (add,metrics) #fg.connect (metrics,va,dst) - fg.connect (add,va,dst) + fg.connect (add,skip,va,dst) fg.run() data = dst.data() - ntotal = len(data) - 2*L + ntotal = len(data) - L nright=0 for i in range(ntotal): - if packet[i+L]==data[i+L]: + if packet[i+L]==data[i]: nright=nright+1 #else: #print "Error in ", i |