From f1c41f807cb29472d0924149e39d6ec8ad90e6a2 Mon Sep 17 00:00:00 2001
From: eb <eb@221aa14e-8319-0410-a670-987f0aec2ac5>
Date: Wed, 27 Sep 2006 05:14:03 +0000
Subject: Merged changes from eb/digital-wip into trunk.
This includes:
* renaming gnuradio-examples/python/gmsk2 to gnuradio-examples/python/digital
* refactoring the digital data tx and rx test code into benchmark_tx
and benchmark_rx. These accept a -m <modulation> argument.
<modulation> can currently be selected from gmsk, dbpsk, dqpsk
* Two new AGC blocks: gr_agc2: separate attack and delay rates;
gr_feedforward_agc: FIR-ish compressor. Normalizes to peak envelope.
* Working DBPSK mod/demod (works fine)
* Working DQPSK mod/demod (works, but still needs more work)
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@3662 221aa14e-8319-0410-a670-987f0aec2ac5
---
.../python/digital/limbo/qpsk_tester.py | 127 +++++++++++++++++++++
1 file changed, 127 insertions(+)
create mode 100644 gnuradio-examples/python/digital/limbo/qpsk_tester.py
(limited to 'gnuradio-examples/python/digital/limbo/qpsk_tester.py')
diff --git a/gnuradio-examples/python/digital/limbo/qpsk_tester.py b/gnuradio-examples/python/digital/limbo/qpsk_tester.py
new file mode 100644
index 0000000000..ea7bae2ebc
--- /dev/null
+++ b/gnuradio-examples/python/digital/limbo/qpsk_tester.py
@@ -0,0 +1,127 @@
+#!/usr/bin/env python
+
+import random
+from gnuradio import gr
+
+default_access_code = '\xAC\xDD\xA4\xE2\xF2\x8C\x20\xFC'
+
+def string_to_1_0_list(s):
+ r = []
+ for ch in s:
+ x = ord(ch)
+ for i in range(8):
+ t = (x >> i) & 0x1
+ r.append(t)
+
+ return r
+
+def to_1_0_string(L):
+ return ''.join(map(lambda x: chr(x + ord('0')), L))
+
+code = string_to_1_0_list(default_access_code)
+access_code = to_1_0_string(code)
+
+use_agc = 0
+use_rrc_tx = 1
+use_rrc_rx = 1
+use_sync_loop = 1
+use_clock_sync = 1
+
+def main():
+ fg = gr.flow_graph()
+
+# data = (1,2,3,4,5,6,7,8,9)
+ random.seed()
+ data = [random.randint(1,100) for i in range(20000)]
+ data[0] = 0 # you know, for the diff encoding stuff
+ bytes_src = gr.vector_source_b(data,False)
+
+ k = 2
+ spb = 50
+ ntaps = 11*spb
+ excess_bw = 0.9
+ threshold = 12
+ constellation = (1+0j, 0+1j, -1+0j, 0-1j)
+
+ bytes2chunks = gr.packed_to_unpacked_bb(k, gr.GR_MSB_FIRST)
+ diffenc = gr.diff_encoder_bb(4)
+ chunks2symbols = gr.chunks_to_symbols_bc(constellation)
+
+ if use_rrc_tx:
+ rrc_taps_tx = gr.firdes.root_raised_cosine(spb, spb, 1.0, \
+ excess_bw, ntaps)
+ rrc_tx = gr.interp_fir_filter_ccf(spb, rrc_taps_tx)
+ else:
+ rrc_tx = gr.interp_fir_filter_ccf(1, (1,))
+
+################### CHANNEL MODEL #############################
+
+ phase_rotate = gr.multiply_const_cc(1-0.36j)
+ channel = gr.add_cc()
+ awgn = gr.noise_source_c(gr.GR_GAUSSIAN, 0.5)
+ fg.connect(awgn, (channel,1))
+
+################### CHANNEL MODEL #############################
+
+ if use_agc:
+ agc = gr.agc_cc(1e-4, 1, 1)
+ else:
+ agc = gr.multiply_const_cc(1)
+
+ # Downconverter
+ if use_sync_loop:
+ costas_alpha=0.005
+ beta = costas_alpha*costas_alpha*0.25
+ sync_loop = gr.costas_loop_cc(costas_alpha, beta, 0.05, -0.05, 0)
+ else:
+ sync_loop = gr.multiply_const_cc(1)
+
+ if use_rrc_rx:
+ rrc_taps_rx = gr.firdes.root_raised_cosine(1, spb, 1.0, \
+ excess_bw, ntaps)
+ rrc_rx = gr.fir_filter_ccf(1, rrc_taps_rx)
+ else:
+ rrc_rx = gr.fir_filter_ccf(1, (1,))
+
+ # Sampler
+ if use_clock_sync:
+ mu = 0.05
+ omega = spb
+ gain_mu = 0.05
+ gain_omega = 0.25*gain_mu*gain_mu
+ omega_rel_limit = 0.5
+ clock_sync = gr.clock_recovery_mm_cc(omega, gain_omega, mu, \
+ gain_mu, omega_rel_limit)
+ #clock_sync.set_verbose(True);
+ else:
+ clock_sync = gr.fir_filter_ccf(1, (1,))
+
+ diff_phasor = gr.diff_phasor_cc()
+ slicer = gr.constellation_decoder_cb((constellation), (0,1,2,3))
+ unpack = gr.unpack_k_bits_bb(k)
+ access = gr.correlate_access_code_bb(access_code,threshold)
+
+ sink = gr.file_sink(gr.sizeof_char, 'output.dat')
+
+ fg.connect(bytes_src, bytes2chunks, diffenc, chunks2symbols, rrc_tx)
+ fg.connect(rrc_tx, phase_rotate, channel, agc)
+ fg.connect(agc, sync_loop, rrc_rx, clock_sync, diff_phasor, slicer, sink)
+
+ test = gr.file_sink(gr.sizeof_gr_complex, 'test.dat')
+ fg.connect(rrc_rx, test)
+
+ fg.connect(chunks2symbols, gr.file_sink(gr.sizeof_gr_complex, 'rrc_tx.dat')) # into TX RRC
+ fg.connect(channel, gr.file_sink(gr.sizeof_gr_complex, 'channel.dat')) # Out of TX RRC
+ fg.connect(rrc_rx, gr.file_sink(gr.sizeof_gr_complex, 'rrc_rx.dat')) # Out of RX RRC -> clock_sync
+ fg.connect(clock_sync, gr.file_sink(gr.sizeof_gr_complex, 'clock_sync.dat')) # Out of M&M sync loop
+ fg.connect(bytes2chunks, gr.file_sink(gr.sizeof_char, 'source.dat'))
+
+ fg.start()
+ fg.wait()
+
+if __name__ == "__main__":
+ main()
+
+
+
+
--
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