mirror of
https://github.com/rtlsdrblog/rtl-sdr-blog.git
synced 2024-11-10 04:37:37 +01:00
rtl_adsb: prototype
Signed-off-by: Steve Markgraf <steve@steve-m.de>
This commit is contained in:
Kyle Keen
Steve Markgraf
parent
d6107bb059
commit
562fd7e8e3
@ -71,7 +71,8 @@ add_executable(rtl_tcp rtl_tcp.c)
|
||||
add_executable(rtl_test rtl_test.c)
|
||||
add_executable(rtl_fm rtl_fm.c)
|
||||
add_executable(rtl_eeprom rtl_eeprom.c)
|
||||
set(INSTALL_TARGETS rtlsdr_shared rtlsdr_static rtl_sdr rtl_tcp rtl_test rtl_fm rtl_eeprom)
|
||||
add_executable(rtl_adsb rtl_adsb.c)
|
||||
set(INSTALL_TARGETS rtlsdr_shared rtlsdr_static rtl_sdr rtl_tcp rtl_test rtl_fm rtl_eeprom rtl_adsb)
|
||||
|
||||
target_link_libraries(rtl_sdr rtlsdr_shared
|
||||
${LIBUSB_LIBRARIES}
|
||||
@ -93,6 +94,10 @@ target_link_libraries(rtl_eeprom rtlsdr_shared
|
||||
${LIBUSB_LIBRARIES}
|
||||
${CMAKE_THREAD_LIBS_INIT}
|
||||
)
|
||||
target_link_libraries(rtl_adsb rtlsdr_shared
|
||||
${LIBUSB_LIBRARIES}
|
||||
${CMAKE_THREAD_LIBS_INIT}
|
||||
)
|
||||
if(UNIX)
|
||||
target_link_libraries(rtl_fm m)
|
||||
if(APPLE)
|
||||
@ -108,11 +113,13 @@ target_link_libraries(rtl_tcp libgetopt_static)
|
||||
target_link_libraries(rtl_test libgetopt_static)
|
||||
target_link_libraries(rtl_fm libgetopt_static)
|
||||
target_link_libraries(rtl_eeprom libgetopt_static)
|
||||
target_link_libraries(rtl_adsb libgetopt_static)
|
||||
set_property(TARGET rtl_sdr APPEND PROPERTY COMPILE_DEFINITIONS "rtlsdr_STATIC" )
|
||||
set_property(TARGET rtl_tcp APPEND PROPERTY COMPILE_DEFINITIONS "rtlsdr_STATIC" )
|
||||
set_property(TARGET rtl_test APPEND PROPERTY COMPILE_DEFINITIONS "rtlsdr_STATIC" )
|
||||
set_property(TARGET rtl_fm APPEND PROPERTY COMPILE_DEFINITIONS "rtlsdr_STATIC" )
|
||||
set_property(TARGET rtl_eeprom APPEND PROPERTY COMPILE_DEFINITIONS "rtlsdr_STATIC" )
|
||||
set_property(TARGET rtl_adsb APPEND PROPERTY COMPILE_DEFINITIONS "rtlsdr_STATIC" )
|
||||
endif()
|
||||
########################################################################
|
||||
# Install built library files & utilities
|
||||
|
||||
@ -10,7 +10,7 @@ lib_LTLIBRARIES = librtlsdr.la
|
||||
librtlsdr_la_SOURCES = librtlsdr.c tuner_e4k.c tuner_fc0012.c tuner_fc0013.c tuner_fc2580.c tuner_r820t.c
|
||||
librtlsdr_la_LDFLAGS = -version-info $(LIBVERSION)
|
||||
|
||||
bin_PROGRAMS = rtl_sdr rtl_tcp rtl_test rtl_fm rtl_eeprom
|
||||
bin_PROGRAMS = rtl_sdr rtl_tcp rtl_test rtl_fm rtl_eeprom rtl_adsb
|
||||
|
||||
rtl_sdr_SOURCES = rtl_sdr.c
|
||||
rtl_sdr_LDADD = librtlsdr.la
|
||||
@ -26,3 +26,6 @@ rtl_fm_LDADD = librtlsdr.la $(LIBM)
|
||||
|
||||
rtl_eeprom_SOURCES = rtl_eeprom.c
|
||||
rtl_eeprom_LDADD = librtlsdr.la $(LIBM)
|
||||
|
||||
rtl_adsb_SOURCES = rtl_adsb.c
|
||||
rtl_adsb_LDADD = librtlsdr.la
|
||||
|
||||
463
src/rtl_adsb.c
Normal file
463
src/rtl_adsb.c
Normal file
@ -0,0 +1,463 @@
|
||||
/*
|
||||
* rtl-sdr, turns your Realtek RTL2832 based DVB dongle into a SDR receiver
|
||||
* Copyright (C) 2012 by Steve Markgraf <steve@steve-m.de>
|
||||
* Copyright (C) 2012 by Hoernchen <la@tfc-server.de>
|
||||
* Copyright (C) 2012 by Kyle Keen <keenerd@gmail.com>
|
||||
* Copyright (C) 2012 by Youssef Touil <youssef@sdrsharp.com>
|
||||
* Copyright (C) 2012 by Ian Gilmour <ian@sdrsharp.com>
|
||||
*
|
||||
* This program is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
|
||||
#include <errno.h>
|
||||
#include <signal.h>
|
||||
#include <string.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
#ifndef _WIN32
|
||||
#include <unistd.h>
|
||||
#else
|
||||
#include <Windows.h>
|
||||
#include <fcntl.h>
|
||||
#include <io.h>
|
||||
#include "getopt/getopt.h"
|
||||
#endif
|
||||
|
||||
#include <semaphore.h>
|
||||
#include <pthread.h>
|
||||
#include <libusb.h>
|
||||
|
||||
#include "rtl-sdr.h"
|
||||
|
||||
#ifdef _WIN32
|
||||
#define sleep Sleep
|
||||
#undef min
|
||||
#undef max
|
||||
#endif
|
||||
|
||||
#define ADSB_RATE 2000000
|
||||
#define ADSB_FREQ 1090000000
|
||||
#define DEFAULT_ASYNC_BUF_NUMBER 32
|
||||
#define DEFAULT_BUF_LENGTH (128 * 16384)
|
||||
#define AUTO_GAIN -100
|
||||
|
||||
static pthread_t demod_thread;
|
||||
static sem_t data_ready;
|
||||
static volatile int do_exit = 0;
|
||||
static rtlsdr_dev_t *dev = NULL;
|
||||
|
||||
/* todo, bundle these up in a struct */
|
||||
uint8_t *buffer;
|
||||
int raw_output = 0;
|
||||
int short_output = 0;
|
||||
int allowed_errors = 5;
|
||||
FILE *file;
|
||||
int adsb_frame[14];
|
||||
#define preamble_len 16
|
||||
#define long_frame 112
|
||||
#define short_frame 56
|
||||
|
||||
void usage(void)
|
||||
{
|
||||
fprintf(stderr,
|
||||
"rtl_adsb, a simple ADS-B decoder\n\n"
|
||||
"Use:\trtl_adsb [-R] [-g gain] [-p ppm] [output file]\n"
|
||||
"\t[-d device_index (default: 0)]\n"
|
||||
"\t[-R output raw bitstream (default: off)]\n"
|
||||
"\t[-S show short frames (default: off)]\n"
|
||||
"\t[-e allowed_errors (default: 5)]\n"
|
||||
"\t[-g tuner_gain (default: automatic)]\n"
|
||||
"\t[-p ppm_error (default: 0)]\n"
|
||||
"\tfilename (a '-' dumps samples to stdout)\n"
|
||||
"\t (omitting the filename also uses stdout)\n\n"
|
||||
"Streaming with netcat:\n"
|
||||
"\trtl_adsb -R | netcat -lp 8080\n"
|
||||
"\twhile true; do rtl_adsb -R | nc -lp 8080; done\n"
|
||||
"\n");
|
||||
exit(1);
|
||||
}
|
||||
|
||||
#ifdef _WIN32
|
||||
BOOL WINAPI
|
||||
sighandler(int signum)
|
||||
{
|
||||
if (CTRL_C_EVENT == signum) {
|
||||
fprintf(stderr, "Signal caught, exiting!\n");
|
||||
do_exit = 1;
|
||||
rtlsdr_cancel_async(dev);
|
||||
return TRUE;
|
||||
}
|
||||
return FALSE;
|
||||
}
|
||||
#else
|
||||
static void sighandler(int signum)
|
||||
{
|
||||
fprintf(stderr, "Signal caught, exiting!\n");
|
||||
do_exit = 1;
|
||||
rtlsdr_cancel_async(dev);
|
||||
}
|
||||
#endif
|
||||
|
||||
void display(int *frame, int len)
|
||||
{
|
||||
int i;
|
||||
if (!short_output && len <= short_frame) {
|
||||
return;}
|
||||
if (raw_output) {
|
||||
fprintf(file, "*");
|
||||
for (i=0; i<((len+7)/8); i++) {
|
||||
fprintf(file, "%02x", frame[i]);}
|
||||
fprintf(file, ";\r\n");
|
||||
return;
|
||||
}
|
||||
fprintf(file, "----------\n");
|
||||
fprintf(file, "DF=%x CA=%x\n", (frame[0] >> 3) & 0x1f, frame[0] & 0x07);
|
||||
fprintf(file, "ICAO Address=%06x\n", frame[1] << 16 | frame[2] << 8 | frame[3]);
|
||||
if (len <= short_frame) {
|
||||
return;}
|
||||
fprintf(file, "PI=0x%06x\n", frame[11] << 16 | frame[12] << 8 | frame[13]);
|
||||
fprintf(file, "Type Code=%x S.Type/Ant.=%x\n", (frame[4] >> 3) & 0x1f, frame[4] & 0x07);
|
||||
}
|
||||
|
||||
int magnitute(unsigned char *buf, int len)
|
||||
/* takes i/q, changes buf in place, returns new len */
|
||||
{
|
||||
int i, mag;
|
||||
for (i=0; i<len; i+=2) {
|
||||
mag = abs((int)buf[i]-128) + abs((int)buf[i+1]-128);
|
||||
if (mag > 255) { // todo, compression
|
||||
mag = 255;}
|
||||
buf[i/2] = (unsigned char)mag;
|
||||
}
|
||||
return len/2;
|
||||
}
|
||||
|
||||
inline unsigned char single_manchester(unsigned char a, unsigned char b, unsigned char c, unsigned char d)
|
||||
/* takes 4 consecutive real samples, return 0 or 1, 255 on error */
|
||||
{
|
||||
int bit, bit_p;
|
||||
bit_p = a > b;
|
||||
bit = c > d;
|
||||
if ( bit && bit_p && c > b && d < a) {
|
||||
return 1;}
|
||||
if ( bit && !bit_p && c > a && d < b) {
|
||||
return 1;}
|
||||
if (!bit && bit_p && c < a && d > b) {
|
||||
return 0;}
|
||||
if (!bit && !bit_p && c < b && d > a) {
|
||||
return 0;}
|
||||
return 255;
|
||||
}
|
||||
|
||||
inline unsigned char min(unsigned char a, unsigned char b)
|
||||
{
|
||||
return a<b ? a : b;
|
||||
}
|
||||
|
||||
inline unsigned char max(unsigned char a, unsigned char b)
|
||||
{
|
||||
return a>b ? a : b;
|
||||
}
|
||||
|
||||
inline int preamble(unsigned char *buf, int len, int i)
|
||||
/* returns 0/1 for preamble at index i */
|
||||
{
|
||||
int i2;
|
||||
unsigned char low = 0;
|
||||
unsigned char high = 255;
|
||||
for (i2=0; i2<preamble_len; i2++) {
|
||||
switch (i2) {
|
||||
case 0:
|
||||
case 2:
|
||||
case 7:
|
||||
case 9:
|
||||
high = min(high, buf[i+i2]);
|
||||
break;
|
||||
default:
|
||||
low = max(low, buf[i+i2]);
|
||||
break;
|
||||
}
|
||||
if (high <= low) {
|
||||
return 0;}
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
void manchester(unsigned char *buf, int len)
|
||||
/* overwrites magnitude buffer with valid bits (255 on errors) */
|
||||
{
|
||||
/* a and b hold old values to verify local manchester */
|
||||
unsigned char a=0, b=0;
|
||||
unsigned char bit;
|
||||
int i, i2, start, errors;
|
||||
// todo, allow wrap across buffers
|
||||
i = 0;
|
||||
while (i < len) {
|
||||
/* find preamble */
|
||||
for ( ; i < (len - preamble_len); i++) {
|
||||
if (!preamble(buf, len, i)) {
|
||||
continue;}
|
||||
a = buf[i];
|
||||
b = buf[i+1];
|
||||
for (i2=0; i2<preamble_len; i2++) {
|
||||
buf[i+i2] = 253;}
|
||||
i += preamble_len;
|
||||
//printf("preamble found\n");
|
||||
break;
|
||||
}
|
||||
i2 = start = i;
|
||||
errors = 0;
|
||||
/* mark bits until encoding breaks */
|
||||
for ( ; i < len; i+=2, i2++) {
|
||||
bit = single_manchester(a, b, buf[i], buf[i+1]);
|
||||
a = buf[i];
|
||||
b = buf[i+1];
|
||||
if (bit == 255) {
|
||||
errors += 1;
|
||||
if (errors > allowed_errors) {
|
||||
buf[i2] = 255;
|
||||
break;
|
||||
} else {
|
||||
bit = 0;
|
||||
a = 0;
|
||||
b = 255;
|
||||
}
|
||||
}
|
||||
buf[i] = buf[i+1] = 254; /* to be overwritten */
|
||||
buf[i2] = bit;
|
||||
}
|
||||
// todo, nuke short segments
|
||||
//printf("%i\n", i2 - start);
|
||||
}
|
||||
}
|
||||
|
||||
void messages(unsigned char *buf, int len)
|
||||
{
|
||||
int i, i2, start, preamble_found;
|
||||
int data_i, index, shift, frame_len;
|
||||
// todo, allow wrap across buffers
|
||||
for (i=0; i<len; i++) {
|
||||
if (buf[i] > 1) {
|
||||
continue;}
|
||||
frame_len = long_frame;
|
||||
data_i = 0;
|
||||
for (index=0; index<14; index++) {
|
||||
adsb_frame[index] = 0;}
|
||||
for(; i<len && buf[i]<=1 && data_i<frame_len; i++, data_i++) {
|
||||
if (buf[i]) {
|
||||
index = data_i / 8;
|
||||
shift = 7 - (data_i % 8);
|
||||
adsb_frame[index] |= (unsigned char)(1<<shift);
|
||||
}
|
||||
if (data_i == 7) {
|
||||
//if (adsb_frame[0] == 0) {
|
||||
// break;}
|
||||
if (adsb_frame[0] & 0x80) {
|
||||
frame_len = long_frame;}
|
||||
else {
|
||||
frame_len = short_frame;}
|
||||
}
|
||||
}
|
||||
// todo, check CRC
|
||||
if (data_i < (frame_len-1)) {
|
||||
continue;}
|
||||
//fprintf(file, "bits: %i\n", data_i);
|
||||
display(adsb_frame, frame_len);
|
||||
fflush(file);
|
||||
}
|
||||
}
|
||||
|
||||
static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
|
||||
{
|
||||
int dr_val;
|
||||
if (do_exit) {
|
||||
return;}
|
||||
memcpy(buffer, buf, len);
|
||||
sem_getvalue(&data_ready, &dr_val);
|
||||
if (dr_val <= 0) {
|
||||
sem_post(&data_ready);}
|
||||
}
|
||||
|
||||
static void *demod_thread_fn(void *arg)
|
||||
{
|
||||
int len;
|
||||
while (!do_exit) {
|
||||
sem_wait(&data_ready);
|
||||
len = magnitute(buffer, DEFAULT_BUF_LENGTH);
|
||||
manchester(buffer, len);
|
||||
messages(buffer, len);
|
||||
//fsync(file);
|
||||
}
|
||||
rtlsdr_cancel_async(dev);
|
||||
return 0;
|
||||
}
|
||||
|
||||
int main(int argc, char **argv)
|
||||
{
|
||||
#ifndef _WIN32
|
||||
struct sigaction sigact;
|
||||
#endif
|
||||
char *filename = NULL;
|
||||
int n_read, r, opt;
|
||||
int i, gain = AUTO_GAIN; // tenths of a dB
|
||||
uint32_t dev_index = 0;
|
||||
int device_count;
|
||||
int ppm_error = 0;
|
||||
char vendor[256], product[256], serial[256];
|
||||
sem_init(&data_ready, 0, 0);
|
||||
|
||||
while ((opt = getopt(argc, argv, "g:p:e:RS")) != -1)
|
||||
{
|
||||
switch (opt) {
|
||||
case 'd':
|
||||
dev_index = atoi(optarg);
|
||||
break;
|
||||
case 'g':
|
||||
gain = (int)(atof(optarg) * 10);
|
||||
break;
|
||||
case 'p':
|
||||
ppm_error = atoi(optarg);
|
||||
break;
|
||||
case 'R':
|
||||
raw_output = 1;
|
||||
break;
|
||||
case 'S':
|
||||
short_output = 1;
|
||||
break;
|
||||
case 'e':
|
||||
allowed_errors = atoi(optarg);
|
||||
break;
|
||||
default:
|
||||
usage();
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
if (argc <= optind) {
|
||||
//usage();
|
||||
filename = "-";
|
||||
} else {
|
||||
filename = argv[optind];
|
||||
}
|
||||
|
||||
buffer = malloc(DEFAULT_BUF_LENGTH * sizeof(uint8_t));
|
||||
|
||||
device_count = rtlsdr_get_device_count();
|
||||
if (!device_count) {
|
||||
fprintf(stderr, "No supported devices found.\n");
|
||||
exit(1);
|
||||
}
|
||||
|
||||
fprintf(stderr, "Found %d device(s):\n", device_count);
|
||||
for (i = 0; i < device_count; i++) {
|
||||
rtlsdr_get_device_usb_strings(i, vendor, product, serial);
|
||||
fprintf(stderr, " %d: %s, %s, SN: %s\n", i, vendor, product, serial);
|
||||
}
|
||||
fprintf(stderr, "\n");
|
||||
|
||||
fprintf(stderr, "Using device %d: %s\n",
|
||||
dev_index, rtlsdr_get_device_name(dev_index));
|
||||
|
||||
r = rtlsdr_open(&dev, dev_index);
|
||||
if (r < 0) {
|
||||
fprintf(stderr, "Failed to open rtlsdr device #%d.\n", dev_index);
|
||||
exit(1);
|
||||
}
|
||||
#ifndef _WIN32
|
||||
sigact.sa_handler = sighandler;
|
||||
sigemptyset(&sigact.sa_mask);
|
||||
sigact.sa_flags = 0;
|
||||
sigaction(SIGINT, &sigact, NULL);
|
||||
sigaction(SIGTERM, &sigact, NULL);
|
||||
sigaction(SIGQUIT, &sigact, NULL);
|
||||
sigaction(SIGPIPE, &sigact, NULL);
|
||||
#else
|
||||
SetConsoleCtrlHandler( (PHANDLER_ROUTINE) sighandler, TRUE );
|
||||
#endif
|
||||
|
||||
if (strcmp(filename, "-") == 0) { /* Write samples to stdout */
|
||||
file = stdout;
|
||||
#ifdef _WIN32
|
||||
_setmode(_fileno(file), _O_BINARY);
|
||||
#endif
|
||||
} else {
|
||||
file = fopen(filename, "wb");
|
||||
if (!file) {
|
||||
fprintf(stderr, "Failed to open %s\n", filename);
|
||||
exit(1);
|
||||
}
|
||||
}
|
||||
|
||||
/* Set the tuner gain */
|
||||
if (gain == AUTO_GAIN) {
|
||||
r = rtlsdr_set_tuner_gain_mode(dev, 0);
|
||||
} else {
|
||||
r = rtlsdr_set_tuner_gain_mode(dev, 1);
|
||||
r = rtlsdr_set_tuner_gain(dev, gain);
|
||||
}
|
||||
if (r != 0) {
|
||||
fprintf(stderr, "WARNING: Failed to set tuner gain.\n");
|
||||
} else if (gain == AUTO_GAIN) {
|
||||
fprintf(stderr, "Tuner gain set to automatic.\n");
|
||||
} else {
|
||||
fprintf(stderr, "Tuner gain set to %0.2f dB.\n", gain/10.0);
|
||||
}
|
||||
|
||||
r = rtlsdr_set_freq_correction(dev, ppm_error);
|
||||
r = rtlsdr_set_agc_mode(dev, 1);
|
||||
|
||||
/* Set the tuner frequency */
|
||||
r = rtlsdr_set_center_freq(dev, ADSB_FREQ);
|
||||
if (r < 0) {
|
||||
fprintf(stderr, "WARNING: Failed to set center freq.\n");}
|
||||
else {
|
||||
fprintf(stderr, "Tuned to %u Hz.\n", ADSB_FREQ);}
|
||||
|
||||
/* Set the sample rate */
|
||||
fprintf(stderr, "Sampling at %u Hz.\n", ADSB_RATE);
|
||||
r = rtlsdr_set_sample_rate(dev, ADSB_RATE);
|
||||
if (r < 0) {
|
||||
fprintf(stderr, "WARNING: Failed to set sample rate.\n");}
|
||||
|
||||
/* Reset endpoint before we start reading from it (mandatory) */
|
||||
r = rtlsdr_reset_buffer(dev);
|
||||
if (r < 0) {
|
||||
fprintf(stderr, "WARNING: Failed to reset buffers.\n");}
|
||||
|
||||
/* flush old junk */
|
||||
sleep(1);
|
||||
rtlsdr_read_sync(dev, NULL, 4096, NULL);
|
||||
|
||||
pthread_create(&demod_thread, NULL, demod_thread_fn, (void *)(NULL));
|
||||
rtlsdr_read_async(dev, rtlsdr_callback, (void *)(NULL),
|
||||
DEFAULT_ASYNC_BUF_NUMBER,
|
||||
DEFAULT_BUF_LENGTH);
|
||||
|
||||
|
||||
if (do_exit) {
|
||||
fprintf(stderr, "\nUser cancel, exiting...\n");}
|
||||
else {
|
||||
fprintf(stderr, "\nLibrary error %d, exiting...\n", r);}
|
||||
rtlsdr_cancel_async(dev);
|
||||
|
||||
if (file != stdout) {
|
||||
fclose(file);}
|
||||
|
||||
rtlsdr_close(dev);
|
||||
free(buffer);
|
||||
return r >= 0 ? r : -r;
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user