def punctest(self, nc, np):
length = 2046 # should be divisible by nc
data = [random.randint(0, 255) for i in range(length)]
# last K-1 bits are padding, meaning last byte is lost
data[-1] = 0
data = tuple(data)
src = gr.vector_source_b(data)
enc = raw.conv_enc()
dec = raw.conv_dec(length * 8)
punc = raw.conv_punc(nc, np)
depunc = raw.conv_punc(np, nc, 128)
tofloat = gr.uchar_to_float()
offset = gr.multiply_const_ff(255.0)
touchar = gr.float_to_uchar()
dst = gr.vector_sink_b()
rx = gr.vector_sink_b()
self.tb.connect(src, enc, punc, tofloat, offset, touchar, depunc, dec,
dst)
self.tb.connect(punc, rx)
self.tb.run()
rxlen = len(rx.data())
self.assertEqual(rxlen, (length * 8 * 2 * np) / nc)
self.assertEqual(data, dst.data())
def punctest(self, nc, np):
length = 2046 # should be divisible by nc
data = [random.randint(0, 255) for i in range(length)]
# last K-1 bits are padding, meaning last byte is lost
data[-1] = 0
data = tuple(data)
src = gr.vector_source_b(data)
enc = raw.conv_enc()
dec = raw.conv_dec(length * 8)
punc = raw.conv_punc(nc, np)
depunc = raw.conv_punc(np, nc, 128)
tofloat = gr.uchar_to_float()
offset = gr.multiply_const_ff(255.0)
touchar = gr.float_to_uchar()
dst = gr.vector_sink_b()
rx = gr.vector_sink_b()
self.tb.connect(src, enc, punc, tofloat, offset, touchar, depunc, dec, dst)
self.tb.connect(punc, rx)
self.tb.run()
rxlen = len(rx.data())
self.assertEqual(rxlen, (length * 8 * 2 * np) / nc)
self.assertEqual(data, dst.data())
def test(self, ebno, data=None):
random.seed(0)
(nc, np) = self.puncparam
# round number of bytes and symbols (FIXME, this is probably not always round)
# one symbol = self.ncarriers * self.qambits * 0.5 * (np / nc) bits
symbits = self.ncarriers * self.qambits * nc / (2. * np)
#print "symbits = ", symbits
assert int(self.nsymbols * symbits) % 8 == 0
length = int(self.nsymbols * symbits) / 8 # incl padding
#print 'src: %d' % (length-1)
#print 'pad: %d' % length
#print 'fenc: %d' % (length * 8 * 2)
#print 'punc: %f' % (length * 8 * 2. * np / nc)
#print 'intrlv: %f' % ((length * 8 * 2. * np / nc) / (self.ncarriers*self.qambits))
#print 'total bits: %d' % (self.nframes * length * 8 * 2)
if data is None:
data = [ random.randint(0,255) for i in range((length-1)*self.nframes) ]
data = tuple(data)
src = gr.vector_source_b(data)
#src = gr.file_source(gr.sizeof_char, "src1.datb");
dst = gr.vector_sink_b()
fenc = raw.conv_enc()
fdec = raw.conv_dec(length*8)
punc = raw.conv_punc(nc, np)
depunc = raw.conv_punc(np, nc, 128)
pad = raw.conv_punc(length-1, length)
depad = raw.conv_punc(length, length-1)
intrlv = raw.intrlv_bit(self.ncarriers, self.qambits, False)
deintrlv = raw.intrlv_bit(self.ncarriers, self.qambits, True)
qenc = raw.qam_enc(self.qambits)
qdec = raw.qam_dec(self.qambits)
SNR = 10.0**(ebno/10.0)
noise_power_in_channel = 1.0/SNR
noise_voltage = math.sqrt(noise_power_in_channel/2.0)
# AWGN only
noise = gr.noise_source_c(gr.GR_GAUSSIAN, noise_voltage, 0)
chan = gr.add_cc()
self.tb.connect(noise, (chan, 1))
#chan = gr.channel_model(noise_voltage, 0.0, 1.0, [1.0, 0.0]),
tofloat = gr.uchar_to_float()
offset = gr.multiply_const_ff(255.0)
touchar = gr.float_to_uchar()
self.tb.connect(src, # length-1
pad, # length
fenc, # 2*length
punc, # 2*length*np/nc
intrlv, # 2*length*np/nc (% ncarriers*qambits)
qenc, # 2*length*np/nc / qambits (% ncarriers)
chan,
qdec,
#tofloat, offset, touchar,
deintrlv,
depunc,
fdec,
depad,
dst)
#self.tb.connect(src, gr.file_sink(gr.sizeof_char, "src.datb"))
#self.tb.connect(pad, gr.file_sink(gr.sizeof_char, "pad.datb"))
#self.tb.connect(fenc, gr.file_sink(gr.sizeof_char, "fenc.datb"))
#self.tb.connect(punc, gr.file_sink(gr.sizeof_char, "punc.datb"))
#self.tb.connect(qenc, gr.file_sink(gr.sizeof_gr_complex, "qenc.dat"))
#self.tb.connect(qdec, gr.file_sink(gr.sizeof_char, "qdec.datb"))
#self.tb.connect(touchar, gr.file_sink(gr.sizeof_char, "qdec.datb"))
#self.tb.connect(depunc, gr.file_sink(gr.sizeof_char, "depunc.datb"))
#self.tb.connect(fdec, gr.file_sink(gr.sizeof_char, "fdec.datb"))
#self.tb.connect(depad, gr.file_sink(gr.sizeof_char, "depad.datb"))
self.tb.run()
nerrors = 0
for (a,b) in itertools.izip(data, dst.data()):
count = bitCount(a ^ b)
nerrors += count
ber = nerrors*1.0/len(data)/8
print "%d x %g @ %g dB\t#errors = %d\tBER = %g" % (self.qambits, nc/(2.0*np), ebno, nerrors, ber)
return nerrors
