├── src
    ├── blegenerator.hpp
    ├── blegenerator.cpp
    ├── aoatransmitter.cpp
    └── aoareceiver.cpp
├── README.md
├── CMakeLists.txt
└── COPYING


/src/blegenerator.hpp:
--------------------------------------------------------------------------------
1 | #ifndef BLEGENERATOR
2 | #define BLEGENERATOR
3 | 
4 | std::vector<int8_t> generatesamples(int tx_chan, int counter, int padbytes);
5 | 
6 | #endif // BLEGENERATOR
7 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | # bleaoa
 2 | ## Tool for measuring Angle of Arrival with BLE5.1 on SDR
 3 | 
 4 | This demo software can be used to measure the accuracy of the Angle of Arrival (AoA) technique adopted in Bluetooth Low Energy (BLE) 5.1. The software runs on Software-Defined Radios (SDR) manufactured by Ettus Research.
 5 | 
 6 | ## Components included
 7 | 
 8 | The programs included in this package run on systems that are connected to SDR platforms. The program running on a specific system depends on the role of the SDR in the experimental setup (transmitter or receiver).
 9 | In particular, the package includes:
10 | 
11 | * **aoatransmitter**: the transmitter sends BLE packets periodically (*beacons*). We have used this program with a USRP N200 SDR.
12 | * **aoareceiver**: the receiver captures the *beacons* and process them in order to determine the AoA of the transmitter. We have used this program with a USRP B210 SDR.
13 | 
14 | The software has been tested on Ubuntu 18.04 and 16.04.
15 | 
16 | ## Setup
17 | 
18 | Before building the programs, ensure that you have installed the USRP Open-Source Toolchain for Ubuntu (instructions [here](https://kb.ettus.com/Building_and_Installing_the_USRP_Open-Source_Toolchain_(UHD_and_GNU_Radio)_on_Linux), only UHD required).
19 | 
20 | Then, prepare the software for building using CMake:
21 | ```
22 |     mkdir build
23 |     cd build
24 |     cmake ..
25 | ```
26 | 
27 | Finally, build all the software with
28 | ```
29 |     make
30 | ```
31 | or build only specific components by specifying the name. For example, to build only *aoareceiver* do:
32 | ```
33 |     make aoareceiver
34 | ```
35 | 
36 | ## Running the software
37 | 
38 | To run the software, first do ```mv``` to the *build* directory.
39 | 
40 | Programs can run with default parameter by executing:
41 | ```
42 |     ./<program>
43 | ```
44 | Arguments accepted by the programs can be shown with:
45 | ```
46 |     ./<program> --help
47 | ```
48 | 
49 | The system running *aoareceiver* will display the AoA of the packets sent by *aoatransmitter*.
50 | AoA is considered wrt. the axis going through the two antennas of the receiver.
51 | 
52 | ## Publications
53 | 
54 | The code in this repository has been used in the following publications:
55 | 
56 | * M. Cominelli, P. Patras, F. Gringoli, [Dead on Arrival: An Empirical Study of The Bluetooth 5.1 Positioning System](https://dl.acm.org/doi/10.1145/3349623.3355475), *WiNTECH '19: Proceedings of the 13th International Workshop on Wireless Network Testbeds, Experimental Evaluation & Characterization*, October 2019
57 | 


--------------------------------------------------------------------------------
/CMakeLists.txt:
--------------------------------------------------------------------------------
 1 | #
 2 | # Copyright 2014-2015 Ettus Research LLC
 3 | #
 4 | # This program is free software: you can redistribute it and/or modify
 5 | # it under the terms of the GNU General Public License as published by
 6 | # the Free Software Foundation, either version 3 of the License, or
 7 | # (at your option) any later version.
 8 | #
 9 | # This program is distributed in the hope that it will be useful,
10 | # but WITHOUT ANY WARRANTY; without even the implied warranty of
11 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 | # GNU General Public License for more details.
13 | #
14 | # You should have received a copy of the GNU General Public License
15 | # along with this program.  If not, see <http://www.gnu.org/licenses/>.
16 | #
17 | 
18 | cmake_minimum_required(VERSION 2.8)
19 | 
20 | list(INSERT CMAKE_MODULE_PATH 0 ${CMAKE_SOURCE_DIR}/cmake/Modules)
21 | 
22 | ### Set up build environment ##################################################
23 | # Choose a static or shared-library build (shared is default, and static will
24 | # probably need some special care!)
25 | # Set this to ON in order to link a static build of UHD:
26 | option(UHD_USE_STATIC_LIBS OFF)
27 | 
28 | # This example also requires Boost:
29 | set(BOOST_REQUIRED_COMPONENTS
30 |     program_options
31 |     system
32 |     thread
33 | )
34 | if(MSVC)
35 |     set(BOOST_ALL_DYN_LINK "${BOOST_ALL_DYN_LINK}" CACHE BOOL "boost enable dynamic linking")
36 |     if(BOOST_ALL_DYN_LINK)
37 |         add_definitions(-DBOOST_ALL_DYN_LINK) #setup boost auto-linking in msvc
38 |     else(BOOST_ALL_DYN_LINK)
39 |         set(BOOST_REQUIRED_COMPONENTS) #empty components list for static link
40 |     endif(BOOST_ALL_DYN_LINK)
41 | endif(MSVC)
42 | find_package(Boost "1.46" REQUIRED ${BOOST_REQUIRED_COMPONENTS})
43 | find_package(UHD "3.8.0" REQUIRED)
44 | 
45 | ### Configure Compiler ########################################################
46 | include_directories(
47 |     ${Boost_INCLUDE_DIRS}
48 |     ${UHD_INCLUDE_DIRS}
49 | )
50 | link_directories(${Boost_LIBRARY_DIRS})
51 | 
52 | ### Make the executable #######################################################
53 | add_executable(aoareceiver src/aoareceiver.cpp)
54 | add_executable(aoatransmitter src/aoatransmitter.cpp src/blegenerator.cpp)
55 | 
56 | SET(CMAKE_BUILD_TYPE "Release")
57 | 
58 | # Shared library case: All we need to do is link against the library, and
59 | # anything else we need (in this case, some Boost libraries):
60 | if(NOT UHD_USE_STATIC_LIBS)
61 |     message(STATUS "Linking against shared UHD library.")
62 |     target_link_libraries(aoareceiver ${UHD_LIBRARIES} ${Boost_LIBRARIES})
63 |     target_link_libraries(aoatransmitter ${UHD_LIBRARIES} ${Boost_LIBRARIES})
64 | # Static library case: 
65 | else(NOT UHD_USE_STATIC_LIBS)
66 |     message(STATUS "Linking against static UHD library.")
67 |     target_link_libraries(aoareceiver
68 |         # We could use ${UHD_LIBRARIES}, but linking requires some extra flags,
69 |         # so we use this convenience variable provided to us
70 |         ${UHD_STATIC_LIB_LINK_FLAG}
71 |         # Also, when linking statically, we need to pull in all the deps for
72 |         # UHD as well, because the dependencies don't get resolved automatically
73 |         ${UHD_STATIC_LIB_DEPS}
74 |     )
75 |     target_link_libraries(aoatransmitter
76 |         ${UHD_STATIC_LIB_LINK_FLAG}
77 |         ${UHD_STATIC_LIB_DEPS}
78 |     )
79 | endif(NOT UHD_USE_STATIC_LIBS)
80 | 
81 | ### Once it's built... ########################################################
82 | # Do nothing...
83 | 


--------------------------------------------------------------------------------
/src/blegenerator.cpp:
--------------------------------------------------------------------------------
  1 | /*
  2 |  *  Copyright 2017 by Francesco Gringoli <francesco.gringoli@unibs.it>
  3 |  *  Copyright 2017 by Jiang Wei <jiangwei@jiangwei.org>
  4 |  *  Copyright 2015 by Xianjun Jiao (putaoshu@gmail.com)
  5 |  *  Copyright 2013 Florian Echtler <floe@butterbrot.org>
  6 |  *
  7 |  * This file is part of some open source application.
  8 |  *
  9 |  * Some open source application is free software: you can redistribute
 10 |  * it and/or modify it under the terms of the GNU General Public
 11 |  * License as published by the Free Software Foundation, either
 12 |  * version 3 of the License, or (at your option) any later version.
 13 |  *
 14 |  * Some open source application is distributed in the hope that it will
 15 |  * be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
 16 |  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 |  * GNU General Public License for more details.
 18 |  *
 19 |  * You should have received a copy of the GNU General Public License
 20 |  * along with the application. If not, see <http://www.gnu.org/licenses/>.
 21 |  */
 22 | 
 23 | #include <stdio.h>
 24 | #include <iostream>
 25 | #include <complex>
 26 | #define _USE_MATH_DEFINES
 27 | #include <math.h>
 28 | #include <inttypes.h>
 29 | #include <stdint.h>
 30 | #include <vector>
 31 | #include <functional>
 32 | #include <arpa/inet.h>
 33 | 
 34 | #define MAX_NUM_PHY_SAMPLE 1520
 35 | #define MAX_NUM_CHAR_CMD (256)
 36 | #define MAX_NUM_PHY_BYTE (47)
 37 | #define SAMPLE_PER_SYMBOL 2  // 
 38 | #define LEN_GAUSS_FILTER (4) // pre 2, post 2
 39 | #define MAX_LE_SYMBOLS 64
 40 | 
 41 | #define LE_ADV_AA 0x8E89BED6
 42 | 
 43 | class BLESDR {
 44 | public:
 45 |         BLESDR();
 46 |         ~BLESDR();
 47 |         std::vector<float> sample_for_raw_packet(size_t chan, int counter);
 48 | 
 49 | private:
 50 |         std::vector<float> iqsamples;
 51 |         size_t byte_to_bits(uint8_t* byte, size_t len, char* bits);
 52 |         float* generate_gaussian_taps(unsigned samples_per_sym, unsigned L, double bt);
 53 |         void btle_calc_crc(void* src, uint8_t len, uint8_t* dst);
 54 |         void btle_whiten(uint8_t chan, uint8_t* buf, uint8_t len);
 55 | 
 56 |         int gen_sample_from_phy_bit(char *bit, float *sample, int num_bit);
 57 |         float tmp_phy_bit_over_sampling[MAX_NUM_PHY_SAMPLE + 2 * LEN_GAUSS_FILTER*SAMPLE_PER_SYMBOL];
 58 |         float tmp_phy_bit_over_sampling1[MAX_NUM_PHY_SAMPLE];
 59 |         float * gauss_coef;
 60 | 
 61 |         uint8_t chan;
 62 |         int srate;
 63 | 
 64 | 	void dump_btle_packet(uint8_t *packet, int length);
 65 | 
 66 | };
 67 | 
 68 | void BLESDR::dump_btle_packet(uint8_t *pp, int length)
 69 | {
 70 |         for(int kk = 0; kk < length; kk ++) {
 71 | 		printf("%02X ", pp[kk]);
 72 | 	}
 73 | 	printf("\n");
 74 | }
 75 | 
 76 | 
 77 | BLESDR::BLESDR() :
 78 | 	chan(37),
 79 | 	srate(2)
 80 | {
 81 | 	gauss_coef = generate_gaussian_taps(SAMPLE_PER_SYMBOL, LEN_GAUSS_FILTER, 0.5);
 82 | }
 83 | 
 84 | BLESDR::~BLESDR() {
 85 | 	delete gauss_coef;
 86 | }
 87 | 
 88 | size_t BLESDR::byte_to_bits(uint8_t* byte, size_t len, char* bits) {
 89 | 
 90 | 	for (int j = 0; j < len; j++) {
 91 | 		for (int i = 0; i < 8; i++) {
 92 | 			// Mask each bit in the byte and store it
 93 | 			bits[j * 8 + i] = (byte[j] >> i) & 1;
 94 | 		}
 95 | 	}
 96 | 	return len * 8;
 97 | }
 98 | 
 99 | void BLESDR::btle_calc_crc(void* src, uint8_t len, uint8_t* dst) {
100 | 
101 | 	uint8_t* buf = (uint8_t*)src;
102 | 
103 | 	// initialize 24-bit shift register in "wire bit order"
104 | 	// dst[0] = bits 23-16, dst[1] = bits 15-8, dst[2] = bits 7-0
105 | 	dst[0] = 0xAA;
106 | 	dst[1] = 0xAA;
107 | 	dst[2] = 0xAA;
108 | 
109 | 	while (len--) {
110 | 
111 | 		uint8_t d = *(buf++);
112 | 
113 | 		for (uint8_t i = 1; i; i <<= 1, d >>= 1) {
114 | 
115 | 			// save bit 23 (highest-value), left-shift the entire register by one
116 | 			uint8_t t = dst[0] & 0x01;         dst[0] >>= 1;
117 | 			if (dst[1] & 0x01) dst[0] |= 0x80; dst[1] >>= 1;
118 | 			if (dst[2] & 0x01) dst[1] |= 0x80; dst[2] >>= 1;
119 | 
120 | 			// if the bit just shifted out (former bit 23) and the incoming data
121 | 			// bit are not equal (i.e. bit_out ^ bit_in == 1) => toggle tap bits
122 | 			if (t != (d & 1)) {
123 | 				// toggle register tap bits (=XOR with 1) according to CRC polynom
124 | 				dst[2] ^= 0xDA; // 0b11011010 inv. = 0b01011011 ^= x^6+x^4+x^3+x+1
125 | 				dst[1] ^= 0x60; // 0b01100000 inv. = 0b00000110 ^= x^10+x^9
126 | 			}
127 | 		}
128 | 	}
129 | }
130 | 
131 | void BLESDR::btle_whiten(uint8_t chan, uint8_t* buf, uint8_t len)
132 | {
133 | 
134 | 	// initialize LFSR with current channel, set bit 6
135 | 	uint8_t lfsr = chan | 0x40;
136 | 
137 | 	while (len--) {
138 | 		uint8_t res = 0;
139 | 		// LFSR in "wire bit order"
140 | 		for (uint8_t i = 1; i; i <<= 1) {
141 | 			if (lfsr & 0x01) {
142 | 				lfsr ^= 0x88;
143 | 				res |= i;
144 | 			}
145 | 			lfsr >>= 1;
146 | 		}
147 | 		*(buf++) ^= res;
148 | 	}
149 | }
150 | 
151 | std::vector<float> BLESDR::sample_for_raw_packet(size_t chan, int counter)
152 | {
153 | 	// second byte (packet length) covers from third byte to crc-excluded
154 | 	// last three bytes are CRC
155 | 	uint8_t packet[] = {0x40, 0x1E, 0x8A, 0xCE, 0xEE, 0xB7, 0x69, 0x88, 0x07, 0x1C, 0xB9, 0x16, 0x54, 0x2F, 0x61, 0xAC, 0xCC, 0x27, 0x45, 0x67, 0xF7, 0xDB, 0x34, 0xC4, 0x03, 0x8E, 0x5C, 0x0B, 0xAA, 0x97, 0x30, 0x56, 0x00, 0x00, 0x00};
156 | /*
157 | 0x40, 0x14,                               // header
158 | 			    0x00, 0x11, 0x22, 0x33, 0x44, 0x55,	      // adv mac address
159 | 			    0x02, 0x01, 0x1A, 0x0A, 0xFF, 0x4C, 0x00, // data
160 | 			    0x10, 0x05, 0x0A, 0x10, 0x11, 0xEB, 0x20, // data
161 | 			    0x00, 0x00, 0x00,	                      // crc
162 | 			   };
163 | */
164 | 
165 | 	*(int32_t*)(packet + 12) = htonl(counter);
166 | 	uint8_t preamble = 0xAA;
167 | 	const uint32_t access_address = LE_ADV_AA;
168 | 
169 | 	// calculate CRC over header+MAC+payload, append after payload
170 | 	btle_calc_crc(packet, sizeof(packet) - 3, packet + sizeof(packet) - 3);
171 | 
172 | 	// apply whitening
173 | 	btle_whiten(chan, packet, sizeof(packet));
174 | 
175 | 	// 5 accounts for preamble + AA
176 | 	size_t numbits = (sizeof(packet) + 5) * 8;
177 | 	int offset = 0;
178 | 	char *bits = new char[numbits];
179 | 
180 | 	iqsamples.resize((numbits * SAMPLE_PER_SYMBOL + (LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL)) * 2);
181 | 
182 | 	offset = byte_to_bits(&preamble, 1, bits);
183 | 	offset += byte_to_bits((uint8_t*) &access_address, 4, bits + offset);
184 | 	offset += byte_to_bits(packet, sizeof(packet), bits + offset);
185 | 
186 | 	int num_phy_sample = gen_sample_from_phy_bit(bits, iqsamples.data(), numbits);
187 | 
188 | 	delete bits;
189 | 
190 | 	return iqsamples;
191 | }
192 | 
193 | int BLESDR::gen_sample_from_phy_bit(char *bit, float *sample, int num_bit)
194 | {
195 | 	int num_sample = (num_bit * SAMPLE_PER_SYMBOL) + (LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL);
196 | 	int i, j;
197 | 	for (i = 0; i < (LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL - 1); i++) {
198 | 		tmp_phy_bit_over_sampling[i] = 0.0;
199 | 	}
200 | 	for (i = (1 * LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL - 1 + num_bit * SAMPLE_PER_SYMBOL);
201 | 	     i < (2 * LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL - 2 + num_bit * SAMPLE_PER_SYMBOL);
202 | 	     i ++) {
203 | 		tmp_phy_bit_over_sampling[i] = 0.0;
204 | 	}
205 | 	for (i = 0; i < (num_bit * SAMPLE_PER_SYMBOL); i++) {
206 | 		if (i % SAMPLE_PER_SYMBOL == 0) {
207 | 			tmp_phy_bit_over_sampling[i + (LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL - 1)] =
208 | 				(float)(bit[i / SAMPLE_PER_SYMBOL]) * 2.0 - 1.0;
209 | 		}
210 | 		else {
211 | 			tmp_phy_bit_over_sampling[i + (LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL - 1)] = 0.0;
212 | 		}
213 | 	}
214 | 	int len_conv_result = num_sample - 1;
215 | 	for (i = 0; i < len_conv_result; i++) {
216 | 		float acc = 0;
217 | 		for (j = 0; j < (LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL); j++) {
218 | 			acc = acc + gauss_coef[(LEN_GAUSS_FILTER * SAMPLE_PER_SYMBOL) - j - 1] *
219 | 				    tmp_phy_bit_over_sampling[i + j];
220 | 		}
221 | 		tmp_phy_bit_over_sampling1[i] = acc;
222 | 	}
223 | 	float tmp = 0;
224 | 	sample[0] = cosf(tmp);
225 | 	sample[1] = sinf(tmp);
226 | 	for (i = 1; i < num_sample; i++) {
227 | 		tmp = tmp + (M_PI * 0.5) * tmp_phy_bit_over_sampling1[i - 1] / ((float)SAMPLE_PER_SYMBOL);
228 | 		sample[i * 2 + 0] = cos(tmp);
229 | 		sample[i * 2 + 1] = sin(tmp);
230 | 	}
231 | 	return(num_sample);
232 | }
233 | 
234 | float* BLESDR::generate_gaussian_taps(unsigned samples_per_sym, unsigned L, double bt)
235 | {
236 | 	float* taps = new float[L*samples_per_sym];
237 | 	double scale = 0;
238 | 	double dt = 1.0 / samples_per_sym;
239 | 	double s = 1.0 / (sqrt(log(2.0)) / (2 * M_PI*bt));
240 | 	double t0 = -0.5 * L*samples_per_sym;
241 | 	double ts;
242 | 	for (unsigned i = 0; i < L*samples_per_sym; i++) {
243 | 		t0++;
244 | 		ts = s*dt*t0;
245 | 		taps[i] = exp(-0.5*ts*ts);
246 | 		scale += taps[i];
247 | 	}
248 | 	for (unsigned i = 0; i < L*samples_per_sym; i++)
249 | 		taps[i] = taps[i] / scale;
250 | 
251 | 	return taps;
252 | }
253 | 
254 | std::vector<int8_t> generatesamples(int tx_chan, int counter, int padbytes)
255 | {
256 | 	BLESDR ble;
257 | 	std::vector<float> samples = ble.sample_for_raw_packet(tx_chan, counter);
258 | 	std::vector<int8_t> samples8bit;
259 |         int samplen = samples.size();
260 | 	samples8bit.resize(samplen + padbytes);
261 | 
262 | 	for(int kk = 0; kk < samples8bit.size(); kk ++) {
263 | 		if(kk < samplen) {
264 |                 	float sample = *(samples.data() + kk);
265 |                 	sample = sample * 128;
266 |                 	if(sample > 127) sample = 127;
267 |                 	if(sample < -128) sample = -128;
268 |                 	int8_t val = (int8_t) sample;
269 | 			samples8bit.data()[kk] = val;
270 | 		} else {
271 | 			samples8bit.data()[kk] = 0;
272 | 		}
273 | 	}
274 | 	return samples8bit;
275 | }
276 | 


--------------------------------------------------------------------------------
/src/aoatransmitter.cpp:
--------------------------------------------------------------------------------
  1 | /*
  2 |  * Copyright 2017 Francesco Gringoli <francesco.gringoli@unibs.it>
  3 |  *
  4 |  * This program is free software: you can redistribute it and/or modify
  5 |  * it under the terms of the GNU General Public License as published by
  6 |  * the Free Software Foundation, either version 3 of the License, or
  7 |  * (at your option) any later version.
  8 |  *
  9 |  * This program is distributed in the hope that it will be useful,
 10 |  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 11 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 12 |  * GNU General Public License for more details.
 13 |  *
 14 |  * You should have received a copy of the GNU General Public License
 15 |  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 16 |  */
 17 | 
 18 | #include <uhd/types/tune_request.hpp>
 19 | #include <uhd/utils/thread_priority.hpp>
 20 | #include <uhd/utils/safe_main.hpp>
 21 | #include <uhd/usrp/multi_usrp.hpp>
 22 | #include <uhd/exception.hpp>
 23 | #include <boost/program_options.hpp>
 24 | #include <boost/format.hpp>
 25 | #include <boost/thread.hpp>
 26 | #include <iostream>
 27 | #include <fstream>
 28 | #include <csignal>
 29 | #include <complex>
 30 | #include <pthread.h>
 31 | #include <sys/socket.h>
 32 | #include <netdb.h>
 33 | #include <netinet/in.h>
 34 | #include <arpa/inet.h>
 35 | #include <unistd.h>
 36 | 
 37 | #include "blegenerator.hpp"
 38 | 
 39 | namespace po = boost::program_options;
 40 | static bool stop_signal_called = false;
 41 | void sig_int_handler(int){stop_signal_called = true;}
 42 | 
 43 | struct txthreadpars {
 44 |     uhd::usrp::multi_usrp::sptr *usrp;
 45 |     size_t samps_per_buff;
 46 |     double msdelay;
 47 |     int channel;
 48 | };
 49 | 
 50 | int global_frequency = 0;
 51 | 
 52 | void *tx_thread_routine(void *pars)
 53 | {
 54 |     struct txthreadpars *txpar = (struct txthreadpars *) pars;
 55 |     uhd::usrp::multi_usrp::sptr usrp = *(txpar->usrp);
 56 |     const std::string cpu_format = "sc8";
 57 |     size_t samps_per_buff = txpar->samps_per_buff;
 58 |     int channel = txpar->channel;
 59 | 
 60 |     // create a transmit streamer
 61 |     uhd::stream_args_t stream_args(cpu_format, cpu_format);
 62 |     uhd::tx_streamer::sptr tx_stream = usrp->get_tx_stream(stream_args);
 63 | 
 64 |     // create the stream
 65 |     uhd::tx_metadata_t md;
 66 |     md.start_of_burst = false;
 67 |     md.end_of_burst = false;
 68 | 
 69 |     int counter = 0;
 70 | #define ZERO_PAD_BYTES 100
 71 |     std::cout << "tx start" << std::endl;
 72 | 
 73 |     int old_global_frequency = global_frequency;
 74 | 
 75 |     // generate once for ever
 76 |     do {
 77 |         std::vector<int8_t> buff = generatesamples(channel, counter, ZERO_PAD_BYTES);
 78 |         size_t num_tx_samps = buff.size() / 2;
 79 |         md.end_of_burst = true;
 80 |         int ssent = (int) tx_stream->send(&buff.front(), num_tx_samps, md);
 81 |         // std::cout << "Sent synch" << std::endl;
 82 |         //boost::this_thread::sleep(boost::posix_time::milliseconds(10)); // txpar->msdelay));
 83 | 	counter ++;
 84 |         if (global_frequency != old_global_frequency) {
 85 |             double txfreq = double(global_frequency) * 1000000;
 86 |             uhd::tune_request_t tune_request = uhd::tune_request_t(txfreq);
 87 |             usrp->set_tx_freq(tune_request);
 88 |             old_global_frequency = global_frequency;
 89 |         }
 90 |         else {
 91 | 	    usleep(10000);
 92 |         }
 93 |     } while(not stop_signal_called);
 94 | 
 95 |     //finished
 96 |     std::cout << std::endl << "tx stream done!" << std::endl << std::endl;
 97 |     return NULL;
 98 | 
 99 | }
100 | 
101 | bool check_locked_tx(uhd::usrp::multi_usrp::sptr usrp)
102 | {
103 |     //Check Ref and LO Lock detect
104 |     std::vector<std::string> sensor_names;
105 |     sensor_names = usrp->get_tx_sensor_names(0);
106 |     if (std::find(sensor_names.begin(), sensor_names.end(), "lo_locked") != sensor_names.end()) {
107 |         uhd::sensor_value_t lo_locked = usrp->get_tx_sensor("lo_locked",0);
108 |         std::cout << boost::format("Checking TX: %s ...") % lo_locked.to_pp_string() << std::endl;
109 |         UHD_ASSERT_THROW(lo_locked.to_bool());
110 |     }
111 | 
112 |     return true;
113 | }
114 | 
115 | double ble_chan2freq(int channel)
116 | {
117 | 	double freq = 2402;
118 |         if(channel < 11)
119 |                 freq = 2404 + channel * 2;
120 |         else if(channel < 37)
121 |                 freq = 2428 + (channel - 11) * 2;
122 |         else if(channel == 37)
123 |                 freq = 2402;
124 |         else if(channel == 38)
125 |                 freq = 2426;
126 |         else if(channel == 39)
127 |                 freq = 2480;
128 |         else {
129 |                 fprintf(stderr, "Invalid channel, defaulting to 37\n");
130 |                 freq = 2402;
131 |         }
132 | 
133 | 	return freq * 1e6;
134 | }
135 | 
136 | /*
137 |  * set up a single device for transmitting at the requested channel
138 |  */
139 | uhd::usrp::multi_usrp::sptr usrp_setup(std::string chainname,
140 | 				       std::string args,
141 | 				       double txgain,
142 | 				       int blechannel)
143 | {
144 |     double txfreq = ble_chan2freq(blechannel);
145 | 
146 |     // create a usrp device
147 |     std::cout << boost::format("Setting up chain %s ") % chainname << std::endl;
148 |     std::cout << boost::format("Creating the usrp device with: %s...") % args << std::endl;
149 |     uhd::usrp::multi_usrp::sptr usrp = uhd::usrp::multi_usrp::make(args);
150 |     std::cout << boost::format("Using Device: %s") % usrp->get_pp_string() << std::endl;
151 | 
152 |     // lock mboard clocks
153 |     std::string ref = "internal";
154 |     usrp->set_clock_source(ref);
155 | 
156 |     // always select the subdevice first, the channel mapping affects the other settings
157 |     // if (vm.count("rxsubdev")) usrp->set_rx_subdev_spec("");
158 | 
159 |     //set the sample rate for txing
160 |     double txrate = 2000000;
161 |     std::cout <<
162 | 	boost::format("Setting TX Rate for %s: %f Msps...") % chainname % (txrate / 1e6) <<
163 | 	std::endl;
164 |     usrp->set_tx_rate(txrate);
165 |     std::cout <<
166 | 	boost::format("Actual TX Rate for %s: %f Msps...") % chainname % (usrp->get_tx_rate() / 1e6) <<
167 | 	std::endl;
168 | 
169 |     //set the center frequency
170 |     std::cout <<
171 | 	boost::format("Setting TX Freq for %s: %f MHz...") % chainname % (txfreq / 1e6) <<
172 | 	std::endl;
173 |     uhd::tune_request_t tune_request = uhd::tune_request_t(txfreq);
174 | 
175 |     usrp->set_tx_freq(tune_request);
176 |     std::cout <<
177 | 	boost::format("Actual TX Freq for %s: %f MHz...") % chainname % (usrp->get_tx_freq() / 1e6) <<
178 | 	std::endl;
179 | 
180 |     //set the rf gain
181 |     std::cout <<
182 | 	boost::format("Setting TX Gain for %s: %f dB...") % chainname % txgain <<
183 | 	std::endl;
184 |     usrp->set_tx_gain(txgain);
185 |     std::cout << boost::format("Actual TX Gain for %s: %f dB...") % chainname % usrp->get_tx_gain() <<
186 | 	std::endl;
187 | 
188 |     //set the antenna
189 |     std::string txant = "J1";
190 |     usrp->set_tx_antenna(txant);
191 | 
192 |     return usrp;
193 | }
194 | 
195 | 
196 | int UHD_SAFE_MAIN(int argc, char *argv[])
197 | {
198 |     uhd::set_thread_priority_safe();
199 | 
200 |     //variables to be set by po
201 |     std::string args;
202 |     double txgain;
203 |     int channel;
204 |     size_t samples_per_buffer = 10000;
205 | 
206 |     //setup the program options
207 |     po::options_description desc("Allowed options");
208 |     desc.add_options()
209 |         ("help", "help message")
210 |         ("args", po::value<std::string>(&args)->default_value(""), "multi uhd device address args")
211 |         ("channel", po::value<int>(&channel)->default_value(37), "ble channel")
212 | 	("txgain", po::value<double>(&txgain)->default_value(50), "tx gain for the RF chain")
213 |     ;
214 |     po::variables_map vm;
215 |     po::store(po::parse_command_line(argc, argv, desc), vm);
216 |     po::notify(vm);
217 | 
218 |     //print the help message
219 |     if (vm.count("help")) {
220 |         std::cout << boost::format("ble advertiser. %s") % desc << std::endl;
221 |         std::cout << std::endl;
222 |         return ~0;
223 |     }
224 | 
225 |     uhd::usrp::multi_usrp::sptr usrp;
226 |     usrp = usrp_setup("chain", args, txgain, channel);
227 | 
228 |     double setup_time = 1;
229 |     usleep(100000);
230 |     check_locked_tx(usrp); // check Ref and LO Lock detect
231 |     boost::this_thread::sleep(boost::posix_time::seconds(1)); // allow for some setup time
232 | 
233 |     //set sigint if user wants to interrupt
234 |     std::signal(SIGINT, &sig_int_handler);
235 |     std::cout << "Press Ctrl + C to stop streaming..." << std::endl;
236 | 
237 |     pthread_t txthread;
238 |     struct txthreadpars txpar;
239 |     txpar.usrp = &usrp;
240 |     txpar.samps_per_buff = samples_per_buffer;
241 |     txpar.channel = channel;
242 |     pthread_create(&txthread, NULL, tx_thread_routine, (void *) &txpar);
243 | 
244 |     int soc = socket(PF_INET, SOCK_DGRAM, 0);
245 |     if( soc == -1 ) {
246 |         fprintf(stderr, "Cannot create socket\n");
247 |         return -1;
248 |     }
249 | 
250 |     struct sockaddr_in local, remote;
251 |     local.sin_family = PF_INET;
252 |     local.sin_port = htons ((short) 8082);
253 |     local.sin_addr.s_addr = htonl (INADDR_ANY);
254 | 
255 |     if (bind (soc, (struct sockaddr*)&local, sizeof(local)) == -1) {
256 |         fprintf (stderr, "Cannot bind socket\n");
257 |         close (soc);
258 |         return 1;
259 |     }
260 | 
261 | 
262 | #define BUFFER_LENGTH 1000
263 |     char buffer[BUFFER_LENGTH];
264 | 
265 |     socklen_t size_remote = sizeof(remote);
266 |     while (not stop_signal_called) {
267 |         int retc = recvfrom(soc, buffer, BUFFER_LENGTH, 0, (struct sockaddr*) &remote, &size_remote);
268 | 	if (retc == -1) {
269 |             fprintf(stderr, "Error receiving from socket\n");
270 |             close (soc);
271 |             return 1;
272 |         }
273 |         int *frequency = (int *) buffer;
274 |         printf("new frequency = %d\n", *frequency);
275 |         global_frequency = *frequency;
276 |     }
277 | 
278 |     pthread_join (txthread, NULL);
279 | 
280 |     return EXIT_SUCCESS;
281 | }
282 | 


--------------------------------------------------------------------------------
/src/aoareceiver.cpp:
--------------------------------------------------------------------------------
  1 | /* 
  2 |  * Copyright 2019 Marco Cominelli
  3 |  * Copyright 2019 Francesco Gringoli
  4 |  *
  5 |  * This program is free software: you can redistribute it and/or modify
  6 |  * it under the terms of the GNU General Public License as published by
  7 |  * the Free Software Foundation, either version 3 of the License, or
  8 |  * (at your option) any later version.
  9 |  *
 10 |  * This program is distributed in the hope that it will be useful,
 11 |  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 13 |  * GNU General Public License for more details.
 14 |  *
 15 |  * You should have received a copy of the GNU General Public License
 16 |  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 17 |  */
 18 | 
 19 | #include <uhd/types/tune_request.hpp>
 20 | #include <uhd/utils/thread_priority.hpp>
 21 | #include <uhd/utils/safe_main.hpp>
 22 | #include <uhd/usrp/multi_usrp.hpp>
 23 | #include <boost/program_options.hpp>
 24 | #include <boost/format.hpp>
 25 | #include <boost/thread.hpp>
 26 | #include <boost/lexical_cast.hpp>
 27 | #include <csignal>
 28 | #include <boost/algorithm/string.hpp>
 29 | #include <iostream>
 30 | #include <complex>
 31 | #include <stdio.h>
 32 | #include <stdlib.h>
 33 | #include <pthread.h>
 34 | #include <sys/types.h>
 35 | #include <sys/socket.h>
 36 | #include <arpa/inet.h>
 37 | #include <netinet/in.h>
 38 | #include <unistd.h>
 39 | 
 40 | #define XOR(x,y) ((x && !y) || (!x && y))
 41 | 
 42 | namespace po = boost::program_options;
 43 | 
 44 | volatile static bool stop_signal = false;
 45 | void sigint_handler(int) {stop_signal = true;}
 46 | 
 47 | volatile static int counter = 0;
 48 | 
 49 | pthread_spinlock_t lock[2];
 50 | volatile size_t bankA_nsamps, bankB_nsamps;
 51 | 
 52 | struct proc_pars_t {
 53 |     std::vector<std::complex<float> *> bankA_ptrs;
 54 |     std::vector<std::complex<float> *> bankB_ptrs;
 55 |     size_t samps_per_buff;
 56 | };
 57 | 
 58 | typedef struct MyData {
 59 |     size_t sn;
 60 |     float aoa;
 61 |     float amplitude[2];
 62 | } mydata_t;
 63 | 
 64 | typedef struct Command {
 65 |     int type;
 66 |     int value;
 67 | } cmd_t;
 68 | 
 69 | volatile int do_print = 0;
 70 | bool do_hop = false;
 71 | bool change_gain = false;
 72 | double gain, freq;
 73 | unsigned int freq_inc = 0;
 74 | 
 75 | /*
 76 |  * Useful commands for running experiments.
 77 |  * (type corresponding letters while program is running)
 78 |  */
 79 | void* keyboard_routine(void* pars)
 80 | {
 81 |     while (stop_signal == false) {
 82 |         int c = fgetc(stdin);
 83 |         if (c == 'p') {          // print 1 pkt info to file
 84 |             do_print = 1;
 85 |         } else if (c == 'g') {   // adjust gain
 86 |             change_gain = true;
 87 |         } else if (c == 'h') {   // hop to next channel (0 to 39)
 88 |             do_hop = true;
 89 |         } else if (c == 'r') {   // run complete capture
 90 |             sleep(4);
 91 |             printf("\a");  // beep alert (start)
 92 |             for (int kk = 0; kk < 40; kk++) {
 93 |                 do_hop = true;
 94 |                 sleep(1);
 95 |                 do_print = 30;
 96 |                 while(do_print > 0) usleep(5000);
 97 |             }
 98 |             printf("\a");  // beep alert (stop)
 99 |         }
100 |         usleep(1000);
101 |     }
102 | 
103 |     return NULL;
104 | }
105 | 
106 | 
107 | inline void dewhiten(uint8_t *pdu, unsigned int length)
108 | {
109 |     /* Scheme of the LFSR used for dewhitening
110 |      *
111 |      *   7   6   5   4   3   2   1   0
112 |      * +---+---+---+---+---+---+---+---+
113 |      * | x | 1 | c | c | c | c | c | c |
114 |      * +---+---+---+---+---+---+---+---+
115 |      *
116 |      * Shifting right every tick.
117 |      */
118 |     uint8_t lfsr = 0x40 | (0x3f & 22); // Channel 22 hardcoded
119 |     for (unsigned int byte = 0; byte < length; byte++) {
120 |         for (int b = 0x01; b <= 0x80; b <<=1) {
121 |             if (lfsr & 0x01) {
122 |                 pdu[byte] ^= b;
123 |                 lfsr ^= 0x88;
124 |             }
125 |             lfsr >>= 1;
126 |         }
127 |     }
128 | }
129 | 
130 | 
131 | uint32_t compute_crc(uint8_t *pdu, int len, uint32_t init_val)
132 | {
133 |     uint32_t crc = init_val;
134 |     while (len--) {
135 |         for (int i = 0x01; i <= 0x80; i <<= 1) {
136 |             uint32_t crc_bit_is_one = crc & 0x00000001;
137 |             uint32_t pdu_bit_is_one = *pdu & i;
138 |             if ( XOR(crc_bit_is_one,pdu_bit_is_one) ) {
139 |                 crc ^= 0x01B4C000;
140 |             }
141 |             crc >>= 1;
142 |         }
143 |         pdu++;
144 |     }
145 |     return crc;
146 | }
147 | 
148 | 
149 | void *process_routine(void *pars)
150 | {
151 |     struct proc_pars_t *procpars = (struct proc_pars_t *) pars;
152 |     size_t kk = 0, select_bank;
153 |     size_t samps_per_buff = procpars->samps_per_buff;
154 |     size_t circbuf_size = 2 * samps_per_buff;
155 |     std::vector<std::complex<float> *> curr_bank;
156 |     float *phasebuf0 = (float *) malloc(circbuf_size * sizeof(float));
157 |     float *phasebuf1 = (float *) malloc(circbuf_size * sizeof(float));
158 |     uint8_t *binbuf0 = (uint8_t *) malloc(circbuf_size * sizeof(uint8_t));
159 |     float *amplbuf0 = (float *) malloc(circbuf_size * sizeof(float));
160 |     size_t opposite_bank;
161 |     const unsigned int srate = 2;
162 |     std::vector<unsigned int> snarray;
163 |     unsigned int sn;
164 |     float dphase;
165 |     size_t idx;
166 | 
167 |     float *pktphase0 = (float *) malloc(128 * sizeof(float));
168 |     float *pktphase1 = (float *) malloc(128 * sizeof(float));
169 |     
170 |     mydata_t mydata;
171 |     float aoa_ma = 0;
172 | 
173 |     FILE * fptr = fopen("angles.dat", "a");
174 | 
175 |     while (stop_signal == false) {
176 |         select_bank = kk++ % 2;
177 |         // Acquire buffer.
178 |         if (select_bank == 0) curr_bank = procpars->bankA_ptrs;
179 |         else curr_bank = procpars->bankB_ptrs;
180 |         pthread_spin_lock(&lock[select_bank]);
181 | 
182 |         std::complex<float> *buff0_ptr = curr_bank[0];
183 |         std::complex<float> *buff1_ptr = curr_bank[1];
184 | 
185 |         // Compute phase and binary values
186 |         for (int i = 0; i < samps_per_buff; i++) {
187 |             idx = i + samps_per_buff * select_bank;
188 | 
189 |             // Compute phase on both channels.
190 |             phasebuf0[idx] = atan2f(buff0_ptr[i].imag(), buff0_ptr[i].real());
191 |             phasebuf1[idx] = atan2f(buff1_ptr[i].imag(), buff1_ptr[i].real());
192 | 
193 |             // Compute amplitude (only channel 0).
194 |             amplbuf0[idx] = buff0_ptr[i].real() * buff0_ptr[i].real() +
195 |                             buff0_ptr[i].imag() * buff0_ptr[i].imag();
196 | 
197 |             // Compute phase difference (only channel 0).
198 |             dphase = (idx != 0) ? phasebuf0[idx] - phasebuf0[idx-1]
199 |                                 : phasebuf0[0] - phasebuf0[circbuf_size-1];
200 | 
201 |             // Handle phase wrapping.
202 |             if (dphase > M_PI) dphase -= 2 * M_PI;
203 |             else if (dphase < -M_PI) dphase += 2 * M_PI;
204 | 
205 |             // Discriminate bits (only channel 0).
206 |             binbuf0[idx] = (dphase > 0) ? 1 : 0;
207 |         }
208 |         
209 |         opposite_bank = (select_bank + 1) % 2;
210 | 
211 |         sn = 0;
212 | 
213 |         for (int i = 0; i < samps_per_buff; i++) {
214 |             idx = i + samps_per_buff * opposite_bank;
215 |             uint8_t transitions = 0;
216 |             // Detect preamble.
217 |             for (int c = 0; c < 8 * srate; c += srate) {
218 |                 if (binbuf0[(idx+c+srate)%circbuf_size] > binbuf0[(idx+c)%circbuf_size]) {
219 |                     transitions++;
220 |                 }
221 |             }
222 |             if (transitions != 4) continue; // not a preamble
223 | 
224 |             uint32_t aa = 0x00;
225 |             uint32_t offset = idx + 8 * srate;
226 |             for (unsigned int c = 0; c < 32 * srate; c += srate) {
227 |                 // note: (c >> 1) = (c/srate) since srate = 2
228 |                 aa |= binbuf0[(offset + c) % circbuf_size] << (c >> 1);
229 |             }
230 |             if (aa != 0x8e89bed6) continue; // not our aa
231 | 
232 |             // Extract packet length
233 |             offset = idx + (8+32) * srate;
234 | 
235 |             // Extract packet PDU.
236 |             uint8_t length = 30+2+3;
237 |             uint8_t pdu[128] = {0x00};
238 |             for (int byte = 0; byte < length; byte++)
239 |                 for (int b = 0; b < 8; b++)
240 |                     pdu[byte] |= binbuf0[(offset+(byte*8+b)*srate)%circbuf_size] << b;
241 | 
242 |             dewhiten(pdu, length);
243 | 
244 |             uint32_t crc_packet = 0, crc_computed = 0;
245 | 
246 |             for (int byte=0; byte<3; byte++) {
247 |                 int bitpos = 0;
248 | 
249 |                 for (int b = 0x01; b <= 0x80; b <<= 1) {
250 |                     if (pdu[32+byte] & b) {
251 |                         crc_packet |= 0x01 << (byte*8+bitpos);
252 |                     }
253 |                     bitpos++;
254 |                 }
255 |             }
256 |             
257 |             crc_computed = compute_crc(pdu, 32, 0x00AAAAAA);
258 |             if (crc_computed != crc_packet) continue; // Discard wrong CRCs.
259 | 
260 |             sn = pdu[15] | (pdu[14] << 8) | (pdu[13] << 16) | (pdu[12] << 24);
261 | 
262 |             for (int n=0; n<128 ; n++) {
263 |                 pktphase0[n] = phasebuf0[(idx+(8+32+16+8)*2+n)%circbuf_size];
264 |                 pktphase1[n] = phasebuf1[(idx+(8+32+16+8)*2+n)%circbuf_size];
265 |             }
266 | 
267 |             break;
268 |         }
269 | 
270 |         if (sn != 0 && sn >> 20 == 0) {
271 |             float unwphase0[128];
272 |             float unwphase1[128];
273 |             float avg_energy = 0;
274 |             float dphasetmp;
275 | 
276 |             // Unwrap phase
277 |             unwphase0[0] = pktphase0[0];
278 |             unwphase1[0] = pktphase1[0];
279 |             for (int n=1; n<128; n++) {
280 |                 // Channel 0
281 |                 dphasetmp = pktphase0[n]-pktphase0[n-1];
282 |                 if (dphasetmp > M_PI) dphasetmp -= 2 * M_PI;
283 |                 else if (dphasetmp < -M_PI) dphasetmp += 2 * M_PI;
284 |                 unwphase0[n] = unwphase0[n-1] + dphasetmp;
285 |                 // Channel 1
286 |                 dphasetmp = pktphase1[n]-pktphase1[n-1];
287 |                 if (dphasetmp > M_PI) dphasetmp -= 2 * M_PI;
288 |                 else if (dphasetmp < -M_PI) dphasetmp += 2 * M_PI;
289 |                 unwphase1[n] = unwphase1[n-1] + dphasetmp;
290 |             }
291 | 
292 |             float phasediff = 0, phasediff_emulated = 0;
293 |             float amplitude = 0;
294 |             float phaseinc = 0;
295 | 
296 |             for (int n = 0; n < 8; n++) phaseinc += (unwphase0[64+n] - unwphase0[64+n-1]);
297 |             phaseinc /= 8;   // average phase increment
298 |             phasediff_emulated = unwphase0[71] + 2*phaseinc - unwphase1[73];
299 | 
300 |             for (int n = 0; n < 128; n++) {
301 |                 phasediff += (unwphase0[n]-unwphase1[n])/128;
302 |                 amplitude += amplbuf0[(idx+n)%circbuf_size] / 128;
303 |             }
304 | 
305 |             phasediff = fmodf(phasediff, 2 * M_PI);
306 |             phasediff_emulated = fmodf(phasediff, 2 * M_PI);
307 | 
308 |             // Handle phase wrapping.
309 |             if (phasediff > M_PI) phasediff -= 2 * M_PI;
310 |             else if (phasediff < -M_PI) phasediff += 2 * M_PI;
311 | 
312 |             // Handle phase wrapping (emulated phase).
313 |             if (phasediff_emulated > M_PI) phasediff_emulated -= 2 * M_PI;
314 |             else if (phasediff_emulated < -M_PI) phasediff_emulated += 2 * M_PI;
315 |                 
316 | 
317 |             float lambda = 300e6/freq;
318 |             const float d = 0.06;
319 |             mydata.aoa = acos((lambda * phasediff)/(2 * M_PI * d));
320 |             mydata.aoa = mydata.aoa / M_PI * 180;
321 |             mydata.sn = sn;
322 |             mydata.amplitude[0] = amplitude;
323 | 
324 |             if (isnan(mydata.aoa) == 0) {
325 |                 printf("\rsn: %8lu, aoa: %3.0f, ampl: %8.6f, phasediff %8.6f ",
326 |                     mydata.sn, mydata.aoa, amplitude, phasediff_emulated);
327 |                 fflush(stdout);
328 | 
329 |                 if (do_print > 0) {
330 |                     fprintf(fptr, "%d %f %f %f %f %f %u\n",
331 |                         counter,
332 |                         mydata.aoa,
333 |                         phasediff,
334 |                         phasediff_emulated,
335 |                         amplitude,
336 |                         gain,
337 |                         freq_inc/1000000 + 2400);
338 |                     do_print--;
339 |                     counter++;
340 |                 }
341 |             }
342 |         }
343 | 
344 |         // Release buffer
345 |         if (select_bank == 0) bankA_nsamps = 0;
346 |         else bankB_nsamps = 0;
347 |         
348 |         pthread_spin_unlock(&lock[select_bank]);
349 |     }
350 |     
351 |     fclose(fptr);
352 | 
353 |     free(amplbuf0);
354 |     free(pktphase0);
355 |     free(pktphase1);
356 |     free(binbuf0);
357 |     free(phasebuf0);
358 |     free(phasebuf1);
359 | 
360 |     return NULL;
361 | }
362 | 
363 | 
364 | int UHD_SAFE_MAIN(int argc, char *argv[])
365 | {
366 |     uhd::set_thread_priority_safe();
367 | 
368 |     // Variables to be set by program options.
369 |     std::string args, channel_list, subdev;
370 |     double rate;
371 |     size_t total_num_samps;
372 | 
373 |     // Setup program options.
374 |     po::options_description desc("Allowed options");
375 |     desc.add_options()
376 |         ("help",
377 |             "print this help message")
378 |         ("args", po::value<std::string>(&args)->default_value(""),
379 |             "USRP device arguments")
380 |         ("channels", po::value<std::string>(&channel_list)->default_value("0,1"),
381 |             "set channels to use (e.g. \"0\", \"0,1\")")
382 |         ("freq", po::value<double>(&freq)->default_value(2450e6),
383 |             "set the RF center frequency (Hz)")
384 |         ("gain", po::value<double>(&gain)->default_value(30),
385 |             "set RF gain of the receiving chains")
386 |         ("nsamps", po::value<size_t>(&total_num_samps)->default_value(10e3),
387 |             "set total number of samples to receive")
388 |         ("rate", po::value<double>(&rate)->default_value(2e6),
389 |             "set the sampling rate (samples per second)")
390 |         ("subdev", po::value<std::string>(&subdev)->default_value("A:A A:B"),
391 |             "set frontend specification")
392 |     ;
393 |     po::variables_map vm;
394 |     po::store(po::parse_command_line(argc, argv, desc), vm);
395 |     po::notify(vm);
396 | 
397 |     // Print help message;
398 |     if (vm.count("help")) {
399 |         std::cout << "User positioning demo using AoA features" << std::endl;
400 |         std::cout << desc << std::endl;
401 |         return ~0;
402 |     }
403 | 
404 |     // Create a USRP device.
405 |     std::cout << "Creating USRP device..." << std::endl;
406 |     uhd::usrp::multi_usrp::sptr usrp = uhd::usrp::multi_usrp::make(args);
407 |     std::cout << std::endl;
408 | 
409 |     // Select the RX subdevice first; this mapping affects all the settings.
410 |     if (vm.count("subdev")) usrp->set_rx_subdev_spec(subdev);
411 | 
412 |     // Set the rx sample rate on all channels.
413 |     std::cout << boost::format("Setting RX rate to %f MS/s\n")
414 |                 % (rate/1e6);
415 |     usrp->set_rx_rate(rate);
416 |     std::cout << boost::format("Actual RX rate: %f MS/s.\n\n")
417 |                 % (usrp->get_rx_rate()/1e6);
418 | 
419 |     // Lock motherboard clock to internal reference source and reset time register.
420 |     usrp->set_clock_source("internal");
421 |     usrp->set_time_now(uhd::time_spec_t(0.0));
422 |     std::cout << "Device timestamp set to 0.0 s." << std::endl;
423 | 
424 |     // Set the rx center frequency on all channels.
425 |     usrp->set_rx_freq(freq, 0);
426 |     usrp->set_rx_freq(freq, 1);
427 |     std::cout << boost::format("Center frequency set to %f MHz.\n")
428 |                 % (usrp->get_rx_freq()/1e6);
429 | 
430 |     // Set the rx gain on all channels.
431 |     usrp->set_rx_gain(gain, 0);
432 |     usrp->set_rx_gain(gain, 1);
433 |     std::cout << boost::format("Gain set to %.1f dB.\n\n")
434 |                  % (usrp->get_rx_gain());
435 | 
436 |     // Set the rx antennas.
437 |     usrp->set_rx_antenna("TX/RX", 0);
438 |     usrp->set_rx_antenna("TX/RX", 1);
439 | 
440 |     // Select rx channels.
441 |     std::vector<std::string> channel_strings;
442 |     std::vector<size_t> channel_nums;
443 |     boost::split(channel_strings, channel_list, boost::is_any_of("\"',"));
444 |     for (size_t c = 0; c < channel_strings.size(); c++) {
445 |         size_t chan = boost::lexical_cast<int>(channel_strings[c]);
446 |         if (chan < usrp->get_rx_num_channels()) {
447 |             channel_nums.push_back(boost::lexical_cast<int>(channel_strings[c]));
448 |         } else {
449 |             throw std::runtime_error("Invalid channel(s) specified.");
450 |         }
451 |     }
452 | 
453 |     // Create a receive streamer.
454 |     // It linearly maps channels (index0 = channel0, index1 = channel1, ...)
455 |     uhd::stream_args_t stream_args("fc32", "sc16");
456 |     stream_args.channels = channel_nums;
457 |     uhd::rx_streamer::sptr rx_stream = usrp->get_rx_stream(stream_args);
458 | 
459 |     // Setup streaming.
460 |     std::cout << "Begin streaming samples... ";
461 |     uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS);
462 |     stream_cmd.num_samps = total_num_samps;
463 |     stream_cmd.stream_now = false;
464 |     stream_cmd.time_spec = uhd::time_spec_t(2.0);
465 |     rx_stream->issue_stream_cmd(stream_cmd);
466 | 
467 |     // Allocate receiver buffers.
468 |     // There are two banks of memory containing one register per buffer.
469 |     const size_t samps_per_buff = rx_stream->get_max_num_samps();
470 |     std::vector<std::vector<std::complex<float>>> bankA_buffs(
471 |         usrp->get_rx_num_channels(),
472 |         std::vector<std::complex<float>> (samps_per_buff)
473 |     );
474 |     std::vector<std::vector<std::complex<float>>> bankB_buffs(
475 |         usrp->get_rx_num_channels(),
476 |         std::vector<std::complex<float>> (samps_per_buff)
477 |     );
478 | 
479 |     // Create a vector of pointers to each buffer.
480 |     std::vector<std::complex<float> *> bankA_ptrs;
481 |     std::vector<std::complex<float> *> bankB_ptrs;
482 |     for (size_t i = 0; i < bankA_buffs.size(); i++) {
483 |         bankA_ptrs.push_back(&bankA_buffs[i].front());
484 |         bankB_ptrs.push_back(&bankB_buffs[i].front());
485 |     }
486 |     
487 |     uhd::rx_metadata_t md;     // metadata will be filled in by recv()
488 |     double timeout = 10.0;     // timeout for recv()
489 |     size_t num_acc_samps = 0;  // number of accumulated samples
490 | 
491 |     size_t kk = 0;
492 |     size_t select_bank;
493 |     size_t num_rx_samps;
494 |     std::vector<std::complex<float> *> curr_bank;
495 | 
496 |     // Initialise the spinlocks.
497 |     pthread_spin_init(&lock[0], PTHREAD_PROCESS_PRIVATE);
498 |     pthread_spin_init(&lock[1], PTHREAD_PROCESS_PRIVATE);
499 | 
500 |     // Create processing thread and keyboard input thread.
501 |     pthread_t proc_thread;
502 |     pthread_t keyboard_thread;
503 |     struct proc_pars_t proc_pars = {bankA_ptrs, bankB_ptrs, samps_per_buff};
504 |     
505 |     pthread_create(&proc_thread, NULL, process_routine, &proc_pars);
506 |     pthread_create(&keyboard_thread, NULL, keyboard_routine, NULL);
507 | 
508 |     // Set SIGINT for stopping execution.
509 |     std::signal(SIGINT, &sigint_handler);
510 |     std::cout << "Press Ctrl + C to stop streaming." << std::endl;
511 | 
512 |     // To transmitter.
513 |     int txsock = 0;
514 |     struct sockaddr_in txaddr;
515 |     if ((txsock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) stop_signal = true;
516 |     memset (&txaddr, '0', sizeof(txaddr));
517 |     txaddr.sin_family = AF_INET;
518 |     txaddr.sin_port = htons(8082);
519 | 
520 |     // To other receiver.
521 |     int slavesock = 0;
522 |     struct sockaddr_in slaveaddr;
523 |     if ((slavesock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) stop_signal = true;
524 |     memset (&slaveaddr, '0', sizeof(slaveaddr));
525 |     slaveaddr.sin_family = AF_INET;
526 |     slaveaddr.sin_port = htons(8081);
527 | 
528 |     if (inet_pton(AF_INET, "192.168.0.3", &txaddr.sin_addr) <= 0) stop_signal = true;
529 |     if (inet_pton(AF_INET, "192.168.0.2", &slaveaddr.sin_addr) <= 0) stop_signal = true;
530 | 
531 |     while (stop_signal == false) {
532 |         // Select current bank.
533 |         select_bank = kk++ % 2;
534 | 
535 |         if (select_bank == 0) curr_bank = bankA_ptrs;
536 |         else curr_bank = bankB_ptrs;
537 |         pthread_spin_lock(&lock[select_bank]);
538 | 
539 |         // Receive one block of data per channel.
540 |         num_rx_samps = rx_stream->recv(
541 |             curr_bank, samps_per_buff, md, timeout, false
542 |         );
543 | 
544 |         // Throw on all errors.
545 |         if (md.error_code == uhd::rx_metadata_t::ERROR_CODE_OVERFLOW) {
546 |             // do nothing
547 |         }
548 |         else if (md.error_code != uhd::rx_metadata_t::ERROR_CODE_NONE) {
549 |             std::cout << boost::format("\nReceived %u samples.\n") % num_acc_samps;
550 |             throw std::runtime_error(md.strerror());
551 |         }
552 | 
553 |         num_acc_samps += num_rx_samps;
554 |         
555 |         if (select_bank == 0) bankA_nsamps = num_rx_samps;
556 |         else bankB_nsamps = num_rx_samps;
557 |         pthread_spin_unlock(&lock[select_bank]);
558 | 
559 |         if (change_gain) {
560 |             gain = fmodf(gain+10,60);
561 |             usrp->set_rx_gain(gain, 0);
562 |             usrp->set_rx_gain(gain, 1);
563 |             std::cout << boost::format("Gain set to %.1f dB.\n") % (usrp->get_rx_gain());
564 |             change_gain = false;
565 | 
566 |             cmd_t command = {1, (int) gain};
567 |             sendto(slavesock, &command, sizeof(command), 0, (struct sockaddr *)&slaveaddr, sizeof(slaveaddr));
568 |         }
569 | 
570 |         if (do_hop) {
571 |             freq = (float) ((freq_inc) % 80000000) + 2402e6;
572 |             freq_inc += 2000000;
573 |             usrp->set_rx_freq(freq, 0);
574 |             usrp->set_rx_freq(freq, 1);
575 |             std::cout << boost::format("Frequency set to %f MHz.\n") % (usrp->get_rx_freq()/1e6);
576 |             do_hop = false;
577 | 
578 |             int freq_integer = 2400 + freq_inc/1000000;
579 | 
580 |             cmd_t command = {2, freq_integer};
581 |             sendto(txsock, &freq_integer, sizeof(freq_integer), 0, (struct sockaddr*)&txaddr, sizeof(txaddr)); 
582 |             sendto(slavesock, &command, sizeof(command), 0, (struct sockaddr *)&slaveaddr, sizeof(slaveaddr));
583 |         }
584 |     }
585 | 
586 |     pthread_join(proc_thread, NULL);
587 |     pthread_cancel(keyboard_thread);
588 | 
589 |     pthread_spin_destroy(&lock[0]);
590 |     pthread_spin_destroy(&lock[1]);
591 |     std::cout << boost::format("\nReceived %u samples.\n") % num_acc_samps;
592 |     std::cout << "Done." << std::endl;
593 | 
594 |     return EXIT_SUCCESS;
595 | }
596 | 
597 | 


--------------------------------------------------------------------------------
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--------------------------------------------------------------------------------
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349 | that they are valid under applicable law.  If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 | 
354 |   When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it.  (Additional permissions may be written to require their own
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358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 | 
361 |   Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 | 
365 |     a) Disclaiming warranty or limiting liability differently from the
366 |     terms of sections 15 and 16 of this License; or
367 | 
368 |     b) Requiring preservation of specified reasonable legal notices or
369 |     author attributions in that material or in the Appropriate Legal
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372 |     c) Prohibiting misrepresentation of the origin of that material, or
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388 |   All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10.  If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
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393 | a further restriction but permits relicensing or conveying under this
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403 |   Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 | 
407 |   8. Termination.
408 | 
409 |   You may not propagate or modify a covered work except as expressly
410 | provided under this License.  Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 | 
415 |   However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
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420 | prior to 60 days after the cessation.
421 | 
422 |   Moreover, your license from a particular copyright holder is
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425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 | 
429 |   Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
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432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 | 
435 |   9. Acceptance Not Required for Having Copies.
436 | 
437 |   You are not required to accept this License in order to receive or
438 | run a copy of the Program.  Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance.  However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work.  These actions infringe copyright if you do
443 | not accept this License.  Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 | 
446 |   10. Automatic Licensing of Downstream Recipients.
447 | 
448 |   Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License.  You are not responsible
451 | for enforcing compliance by third parties with this License.
452 | 
453 |   An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations.  If propagation of a covered
456 | work results from an entity transaction, each party to that
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462 | 
463 |   You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License.  For example, you may
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467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 | 
471 |   11. Patents.
472 | 
473 |   A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based.  The
475 | work thus licensed is called the contributor's "contributor version".
476 | 
477 |   A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version.  For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 | 
487 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
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490 | propagate the contents of its contributor version.
491 | 
492 |   In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
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497 | patent against the party.
498 | 
499 |   If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
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502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
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508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 | 
513 |   If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 | 
521 |   A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 


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