1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
#!/usr/bin/env python
#
# Copyright 2013 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# SPDX-License-Identifier: GPL-3.0-or-later
#
#
import random
import numpy
import pmt
from gnuradio import gr, gr_unittest
from gnuradio import digital
from gnuradio import blocks
from gnuradio import channels
from gnuradio.digital.ofdm_txrx import ofdm_tx, ofdm_rx
from gnuradio.digital.utils import tagged_streams
# Set this to true if you need to write out data
LOG_DEBUG_INFO = False
class ofdm_tx_fg (gr.top_block):
def __init__(
self,
data,
len_tag_key,
scramble_bits=False,
additional_tags=[]):
gr.top_block.__init__(self, "ofdm_tx")
tx_data, tags = tagged_streams.packets_to_vectors((data,), len_tag_key)
src = blocks.vector_source_b(data, False, 1, tags + additional_tags)
self.tx = ofdm_tx(
packet_length_tag_key=len_tag_key,
debug_log=LOG_DEBUG_INFO,
scramble_bits=scramble_bits)
self.sink = blocks.vector_sink_c()
self.connect(src, self.tx, self.sink)
def get_tx_samples(self):
return self.sink.data()
class ofdm_rx_fg (gr.top_block):
def __init__(
self,
samples,
len_tag_key,
channel=None,
prepend_zeros=100,
scramble_bits=False):
gr.top_block.__init__(self, "ofdm_rx")
if prepend_zeros:
samples = (0,) * prepend_zeros + tuple(samples)
src = blocks.vector_source_c(list(samples) + [0, ] * 1000)
self.rx = ofdm_rx(
frame_length_tag_key=len_tag_key,
debug_log=LOG_DEBUG_INFO,
scramble_bits=scramble_bits)
if channel is not None:
self.connect(src, channel, self.rx)
else:
self.connect(src, self.rx)
self.sink = blocks.vector_sink_b()
self.connect(self.rx, self.sink)
def get_rx_bytes(self):
return self.sink.data()
class test_ofdm_txrx (gr_unittest.TestCase):
def setUp(self):
random.seed(0)
self.tb = gr.top_block()
def tearDown(self):
self.tb = None
def test_001_tx(self):
""" Just make sure the Tx works in general """
# This tag gets put onto the first item of the transmit data,
# it should be transmitted first, too
timing_tag = gr.tag_t()
timing_tag.offset = 0
timing_tag.key = pmt.string_to_symbol('tx_timing')
timing_tag.value = pmt.to_pmt('now')
len_tag_key = 'frame_len'
n_bytes = 52
n_samples_expected = (numpy.ceil(1.0 * (n_bytes + 4) / 6) + 3) * 80
test_data = [random.randint(0, 255) for x in range(n_bytes)]
tx_fg = ofdm_tx_fg(
test_data,
len_tag_key,
additional_tags=[
timing_tag,
])
tx_fg.run()
self.assertEqual(len(tx_fg.get_tx_samples()), n_samples_expected)
tags_rx = [gr.tag_to_python(x) for x in tx_fg.sink.tags()]
tags_rx = sorted([(x.offset, x.key, x.value) for x in tags_rx])
tags_expected = [
(0, 'frame_len', n_samples_expected),
(0, 'tx_timing', 'now'),
]
self.assertEqual(tags_rx, tags_expected)
def test_002_rx_only_noise(self):
""" Run the RX with only noise, check it doesn't crash
or return a burst. """
len_tag_key = 'frame_len'
samples = (0,) * 1000
channel = channels.channel_model(0.1)
rx_fg = ofdm_rx_fg(samples, len_tag_key, channel)
rx_fg.run()
self.assertEqual(len(rx_fg.get_rx_bytes()), 0)
def test_003_tx1packet(self):
""" Transmit one packet, with slight AWGN and slight frequency + timing offset.
Check packet is received and no bit errors have occurred. """
len_tag_key = 'frame_len'
n_bytes = 21
fft_len = 64
test_data = list([random.randint(0, 255) for x in range(n_bytes)])
# 1.0/fft_len is one sub-carrier, a fine freq offset stays below that
freq_offset = 1.0 / fft_len * 0.7
#channel = channels.channel_model(0.01, freq_offset)
channel = None
# Tx
tx_fg = ofdm_tx_fg(test_data, len_tag_key)
tx_fg.run()
tx_samples = tx_fg.get_tx_samples()
# Rx
rx_fg = ofdm_rx_fg(tx_samples, len_tag_key, channel, prepend_zeros=100)
rx_fg.run()
rx_data = rx_fg.get_rx_bytes()
self.assertEqual(list(tx_fg.tx.sync_word1), list(rx_fg.rx.sync_word1))
self.assertEqual(list(tx_fg.tx.sync_word2), list(rx_fg.rx.sync_word2))
self.assertEqual(test_data, rx_data)
def test_003_tx1packet_scramble(self):
""" Same as before, use scrambler. """
len_tag_key = 'frame_len'
n_bytes = 21
fft_len = 64
test_data = list([random.randint(0, 255) for x in range(n_bytes)])
# 1.0/fft_len is one sub-carrier, a fine freq offset stays below that
freq_offset = 1.0 / fft_len * 0.7
#channel = channels.channel_model(0.01, freq_offset)
channel = None
# Tx
tx_fg = ofdm_tx_fg(test_data, len_tag_key, scramble_bits=True)
tx_fg.run()
tx_samples = tx_fg.get_tx_samples()
# Rx
rx_fg = ofdm_rx_fg(
tx_samples,
len_tag_key,
channel,
prepend_zeros=100,
scramble_bits=True)
rx_fg.run()
rx_data = rx_fg.get_rx_bytes()
self.assertEqual(list(tx_fg.tx.sync_word1), list(rx_fg.rx.sync_word1))
self.assertEqual(list(tx_fg.tx.sync_word2), list(rx_fg.rx.sync_word2))
self.assertEqual(test_data, rx_data)
def test_004_tx1packet_large_fO(self):
""" Transmit one packet, with slight AWGN and large frequency offset.
Check packet is received and no bit errors have occurred. """
fft_len = 64
len_tag_key = 'frame_len'
n_bytes = 21
test_data = list([random.randint(0, 255) for x in range(n_bytes)])
#test_data = tuple([255 for x in range(n_bytes)])
# 1.0/fft_len is one sub-carrier
frequency_offset = 1.0 / fft_len * 2.5
channel = channels.channel_model(0.00001, frequency_offset)
# Tx
tx_fg = ofdm_tx_fg(test_data, len_tag_key)
tx_fg.run()
tx_samples = tx_fg.get_tx_samples()
# Rx
rx_fg = ofdm_rx_fg(tx_samples, len_tag_key, channel, prepend_zeros=100)
rx_fg.run()
rx_data = rx_fg.get_rx_bytes()
self.assertEqual(test_data, rx_data)
if __name__ == '__main__':
gr_unittest.run(test_ofdm_txrx)
|
