mirror of https://github.com/lwvmobile/dsd-fme.git
1182 lines
30 KiB
C++
1182 lines
30 KiB
C++
/*
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* rtl-sdr, turns your Realtek RTL2832 based DVB dongle into a SDR receiver
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* Copyright (C) 2012 by Steve Markgraf <steve@steve-m.de>
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* Copyright (C) 2012 by Hoernchen <la@tfc-server.de>
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* Copyright (C) 2012 by Kyle Keen <keenerd@gmail.com>
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* Copyright (C) 2013 by Elias Oenal <EliasOenal@gmail.com>
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* Copyright (C) 2014 by Kyle Keen <keenerd@gmail.com>
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include <string.h>
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#include <signal.h>
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#include <pthread.h>
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#include <unistd.h>
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#include <queue>
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#include <rtl-sdr.h>
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#include "dsd.h"
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#define DEFAULT_SAMPLE_RATE 48000
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#define DEFAULT_BUF_LENGTH (1 * 16384)
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#define MAXIMUM_OVERSAMPLE 16
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#define MAXIMUM_BUF_LENGTH (MAXIMUM_OVERSAMPLE * DEFAULT_BUF_LENGTH)
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#define AUTO_GAIN -100
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#define BUFFER_DUMP 4096
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#define FREQUENCIES_LIMIT 1000
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static int lcm_post[17] = {1,1,1,3,1,5,3,7,1,9,5,11,3,13,7,15,1};
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static int ACTUAL_BUF_LENGTH;
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static int *atan_lut = NULL;
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static int atan_lut_size = 131072; /* 512 KB */
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static int atan_lut_coef = 8;
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//UDP -- keep for compatibility reasons
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#include <netinet/in.h>
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#include <arpa/inet.h>
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static pthread_t socket_freq;
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int rtl_bandwidth;
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int bandwidth_multiplier;
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int bandwidth_divisor = 48000; //divide bandwidth by this to get multiplier for the for j loop to queue.push
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short int volume_multiplier;
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short int port;
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struct dongle_state
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{
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int exit_flag;
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pthread_t thread;
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rtlsdr_dev_t *dev;
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int dev_index;
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uint32_t freq;
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uint32_t rate;
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int gain;
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uint16_t buf16[MAXIMUM_BUF_LENGTH];
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uint32_t buf_len;
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int ppm_error;
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int offset_tuning;
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int direct_sampling;
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int mute;
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struct demod_state *demod_target;
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};
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struct demod_state
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{
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int exit_flag;
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pthread_t thread;
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int16_t lowpassed[MAXIMUM_BUF_LENGTH];
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int lp_len;
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int16_t lp_i_hist[10][6];
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int16_t lp_q_hist[10][6];
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int16_t result[MAXIMUM_BUF_LENGTH];
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int16_t droop_i_hist[9];
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int16_t droop_q_hist[9];
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int result_len;
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int rate_in;
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int rate_out;
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int rate_out2;
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int now_r, now_j;
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int pre_r, pre_j;
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int prev_index;
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int downsample; /* min 1, max 256 */
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int post_downsample;
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int output_scale;
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int squelch_level, conseq_squelch, squelch_hits, terminate_on_squelch;
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int downsample_passes;
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int comp_fir_size;
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int custom_atan;
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int deemph, deemph_a;
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int now_lpr;
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int prev_lpr_index;
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int dc_block, dc_avg;
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void (*mode_demod)(struct demod_state*);
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pthread_rwlock_t rw;
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pthread_cond_t ready;
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pthread_mutex_t ready_m;
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struct output_state *output_target;
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};
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struct output_state
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{
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int rate;
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std::queue<int16_t> queue;
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pthread_rwlock_t rw;
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pthread_cond_t ready;
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pthread_mutex_t ready_m;
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};
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struct controller_state
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{
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int exit_flag;
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pthread_t thread;
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uint32_t freqs[FREQUENCIES_LIMIT];
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int freq_len;
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int freq_now;
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int edge;
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int wb_mode;
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pthread_cond_t hop;
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pthread_mutex_t hop_m;
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};
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struct dongle_state dongle;
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struct demod_state demod;
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struct output_state output;
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struct controller_state controller;
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#define safe_cond_signal(n, m) pthread_mutex_lock(m); pthread_cond_signal(n); pthread_mutex_unlock(m)
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#define safe_cond_wait(n, m) pthread_mutex_lock(m); pthread_cond_wait(n, m); pthread_mutex_unlock(m)
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/* {length, coef, coef, coef} and scaled by 2^15
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for now, only length 9, optimal way to get +85% bandwidth */
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#define CIC_TABLE_MAX 10
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int cic_9_tables[][10] = {
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{0,},
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{9, -156, -97, 2798, -15489, 61019, -15489, 2798, -97, -156},
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{9, -128, -568, 5593, -24125, 74126, -24125, 5593, -568, -128},
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{9, -129, -639, 6187, -26281, 77511, -26281, 6187, -639, -129},
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{9, -122, -612, 6082, -26353, 77818, -26353, 6082, -612, -122},
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{9, -120, -602, 6015, -26269, 77757, -26269, 6015, -602, -120},
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{9, -120, -582, 5951, -26128, 77542, -26128, 5951, -582, -120},
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{9, -119, -580, 5931, -26094, 77505, -26094, 5931, -580, -119},
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{9, -119, -578, 5921, -26077, 77484, -26077, 5921, -578, -119},
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{9, -119, -577, 5917, -26067, 77473, -26067, 5917, -577, -119},
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{9, -199, -362, 5303, -25505, 77489, -25505, 5303, -362, -199},
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};
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void rotate_90(unsigned char *buf, uint32_t len)
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/* 90 rotation is 1+0j, 0+1j, -1+0j, 0-1j
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or [0, 1, -3, 2, -4, -5, 7, -6] */
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{
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uint32_t i;
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unsigned char tmp;
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for (i=0; i<len; i+=8) {
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/* uint8_t negation = 255 - x */
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tmp = 255 - buf[i+3];
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buf[i+3] = buf[i+2];
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buf[i+2] = tmp;
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buf[i+4] = 255 - buf[i+4];
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buf[i+5] = 255 - buf[i+5];
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tmp = 255 - buf[i+6];
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buf[i+6] = buf[i+7];
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buf[i+7] = tmp;
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}
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}
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void low_pass(struct demod_state *d)
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/* simple square window FIR */
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{
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int i=0, i2=0;
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while (i < d->lp_len) {
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d->now_r += d->lowpassed[i];
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d->now_j += d->lowpassed[i+1];
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i += 2;
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d->prev_index++;
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if (d->prev_index < d->downsample) {
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continue;
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}
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d->lowpassed[i2] = d->now_r; // * d->output_scale;
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d->lowpassed[i2+1] = d->now_j; // * d->output_scale;
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d->prev_index = 0;
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d->now_r = 0;
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d->now_j = 0;
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i2 += 2;
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}
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d->lp_len = i2;
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}
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int low_pass_simple(int16_t *signal2, int len, int step)
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// no wrap around, length must be multiple of step
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{
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int i, i2, sum;
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for(i=0; i < len; i+=step) {
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sum = 0;
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for(i2=0; i2<step; i2++) {
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sum += (int)signal2[i + i2];
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}
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//signal2[i/step] = (int16_t)(sum / step);
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signal2[i/step] = (int16_t)(sum);
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}
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signal2[i/step + 1] = signal2[i/step];
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return len / step;
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}
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void low_pass_real(struct demod_state *s)
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/* simple square window FIR */
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// add support for upsampling?
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{
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int i=0, i2=0;
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int fast = (int)s->rate_out;
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int slow = s->rate_out2;
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while (i < s->result_len) {
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s->now_lpr += s->result[i];
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i++;
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s->prev_lpr_index += slow;
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if (s->prev_lpr_index < fast) {
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continue;
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}
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s->result[i2] = (int16_t)(s->now_lpr / (fast/slow));
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s->prev_lpr_index -= fast;
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s->now_lpr = 0;
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i2 += 1;
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}
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s->result_len = i2;
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}
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void fifth_order(int16_t *data, int length, int16_t *hist)
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/* for half of interleaved data */
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{
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int i;
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int16_t a, b, c, d, e, f;
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a = hist[1];
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b = hist[2];
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c = hist[3];
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d = hist[4];
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e = hist[5];
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f = data[0];
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/* a downsample should improve resolution, so don't fully shift */
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data[0] = (a + (b+e)*5 + (c+d)*10 + f) >> 4;
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for (i=4; i<length; i+=4) {
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a = c;
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b = d;
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c = e;
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d = f;
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e = data[i-2];
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f = data[i];
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data[i/2] = (a + (b+e)*5 + (c+d)*10 + f) >> 4;
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}
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/* archive */
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hist[0] = a;
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hist[1] = b;
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hist[2] = c;
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hist[3] = d;
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hist[4] = e;
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hist[5] = f;
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}
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void generic_fir(int16_t *data, int length, int *fir, int16_t *hist)
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/* Okay, not at all generic. Assumes length 9, fix that eventually. */
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{
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int d, temp, sum;
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for (d=0; d<length; d+=2) {
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temp = data[d];
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sum = 0;
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sum += (hist[0] + hist[8]) * fir[1];
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sum += (hist[1] + hist[7]) * fir[2];
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sum += (hist[2] + hist[6]) * fir[3];
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sum += (hist[3] + hist[5]) * fir[4];
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sum += hist[4] * fir[5];
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data[d] = sum >> 15 ;
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hist[0] = hist[1];
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hist[1] = hist[2];
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hist[2] = hist[3];
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hist[3] = hist[4];
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hist[4] = hist[5];
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hist[5] = hist[6];
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hist[6] = hist[7];
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hist[7] = hist[8];
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hist[8] = temp;
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}
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}
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// define our own complex math ops because ARMv5 has no hardware float
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void multiply(int ar, int aj, int br, int bj, int *cr, int *cj)
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{
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*cr = ar*br - aj*bj;
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*cj = aj*br + ar*bj;
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}
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int polar_discriminant(int ar, int aj, int br, int bj)
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{
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int cr, cj;
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double angle;
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multiply(ar, aj, br, -bj, &cr, &cj);
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angle = atan2((double)cj, (double)cr);
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return (int)(angle / 3.14159 * (1<<14));
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}
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int fast_atan2(int y, int x)
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/* pre scaled for int16 */
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{
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int yabs, angle;
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int pi4=(1<<12), pi34=3*(1<<12); // note pi = 1<<14
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if (x==0 && y==0) {
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return 0;
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}
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yabs = y;
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if (yabs < 0) {
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yabs = -yabs;
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}
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if (x >= 0) {
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angle = pi4 - pi4 * (x-yabs) / (x+yabs);
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} else {
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angle = pi34 - pi4 * (x+yabs) / (yabs-x);
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}
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if (y < 0) {
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return -angle;
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}
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return angle;
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}
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int polar_disc_fast(int ar, int aj, int br, int bj)
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{
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int cr, cj;
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multiply(ar, aj, br, -bj, &cr, &cj);
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return fast_atan2(cj, cr);
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}
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int atan_lut_init(void)
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{
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int i = 0;
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atan_lut = static_cast<int*>(malloc(atan_lut_size * sizeof(int)));
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for (i = 0; i < atan_lut_size; i++) {
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atan_lut[i] = (int) (atan((double) i / (1<<atan_lut_coef)) / 3.14159 * (1<<14));
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}
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return 0;
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}
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int polar_disc_lut(int ar, int aj, int br, int bj)
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{
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int cr, cj, x, x_abs;
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multiply(ar, aj, br, -bj, &cr, &cj);
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/* special cases */
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if (cr == 0 || cj == 0) {
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if (cr == 0 && cj == 0)
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{return 0;}
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if (cr == 0 && cj > 0)
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{return 1 << 13;}
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if (cr == 0 && cj < 0)
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{return -(1 << 13);}
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if (cj == 0 && cr > 0)
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{return 0;}
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if (cj == 0 && cr < 0)
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{return 1 << 14;}
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}
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/* real range -32768 - 32768 use 64x range -> absolute maximum: 2097152 */
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x = (cj << atan_lut_coef) / cr;
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x_abs = abs(x);
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if (x_abs >= atan_lut_size) {
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/* we can use linear range, but it is not necessary */
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return (cj > 0) ? 1<<13 : -(1<<13);
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}
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if (x > 0) {
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return (cj > 0) ? atan_lut[x] : atan_lut[x] - (1<<14);
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} else {
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return (cj > 0) ? (1<<14) - atan_lut[-x] : -atan_lut[-x];
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}
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return 0;
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}
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void fm_demod(struct demod_state *fm)
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{
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int i, pcm;
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int16_t *lp = fm->lowpassed;
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pcm = polar_discriminant(lp[0], lp[1],
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fm->pre_r, fm->pre_j);
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fm->result[0] = (int16_t)pcm;
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for (i = 2; i < (fm->lp_len-1); i += 2) {
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switch (fm->custom_atan) {
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case 0:
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pcm = polar_discriminant(lp[i], lp[i+1],
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lp[i-2], lp[i-1]);
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break;
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case 1:
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pcm = polar_disc_fast(lp[i], lp[i+1],
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lp[i-2], lp[i-1]);
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break;
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case 2:
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pcm = polar_disc_lut(lp[i], lp[i+1],
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lp[i-2], lp[i-1]);
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break;
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}
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fm->result[i/2] = (int16_t)pcm;
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}
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fm->pre_r = lp[fm->lp_len - 2];
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fm->pre_j = lp[fm->lp_len - 1];
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fm->result_len = fm->lp_len/2;
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}
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void raw_demod(struct demod_state *fm)
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{
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int i;
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for (i = 0; i < fm->lp_len; i++) {
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fm->result[i] = (int16_t)fm->lowpassed[i];
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}
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fm->result_len = fm->lp_len;
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}
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void deemph_filter(struct demod_state *fm)
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{
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static int avg; // cheating...
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int i, d;
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// de-emph IIR
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// avg = avg * (1 - alpha) + sample * alpha;
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for (i = 0; i < fm->result_len; i++) {
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d = fm->result[i] - avg;
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if (d > 0) {
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avg += (d + fm->deemph_a/2) / fm->deemph_a;
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} else {
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avg += (d - fm->deemph_a/2) / fm->deemph_a;
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}
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fm->result[i] = (int16_t)avg;
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}
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}
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void dc_block_filter(struct demod_state *fm)
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{
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int i, avg;
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int64_t sum = 0;
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for (i=0; i < fm->result_len; i++) {
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sum += fm->result[i];
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}
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avg = sum / fm->result_len;
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avg = (avg + fm->dc_avg * 9) / 10;
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for (i=0; i < fm->result_len; i++) {
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fm->result[i] -= avg;
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}
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fm->dc_avg = avg;
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}
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long int rms(int16_t *samples, int len, int step)
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/* largely lifted from rtl_power */
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{
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int i;
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long int rms;
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long p, t, s;
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double dc, err;
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p = t = 0L;
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for (i=0; i<len; i+=step) {
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s = (long)samples[i];
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t += s;
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p += s * s;
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}
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/* correct for dc offset in squares */
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dc = (double)(t*step) / (double)len;
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err = t * 2 * dc - dc * dc * len;
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|
|
rms = (long int)sqrt((p-err) / len);
|
|
//going with a value that's easy to figure out when its done the thing
|
|
if (rms < 0){ rms = 999; }
|
|
return rms;
|
|
}
|
|
|
|
void full_demod(struct demod_state *d)
|
|
{
|
|
int i, ds_p;
|
|
int sr = 0;
|
|
ds_p = d->downsample_passes;
|
|
if (ds_p) {
|
|
for (i=0; i < ds_p; i++) {
|
|
fifth_order(d->lowpassed, (d->lp_len >> i), d->lp_i_hist[i]);
|
|
fifth_order(d->lowpassed+1, (d->lp_len >> i) - 1, d->lp_q_hist[i]);
|
|
}
|
|
d->lp_len = d->lp_len >> ds_p;
|
|
/* droop compensation */
|
|
if (d->comp_fir_size == 9 && ds_p <= CIC_TABLE_MAX) {
|
|
generic_fir(d->lowpassed, d->lp_len,
|
|
cic_9_tables[ds_p], d->droop_i_hist);
|
|
generic_fir(d->lowpassed+1, d->lp_len-1,
|
|
cic_9_tables[ds_p], d->droop_q_hist);
|
|
}
|
|
} else {
|
|
low_pass(d);
|
|
}
|
|
/* power squelch */
|
|
if (d->squelch_level) {
|
|
sr = rms(d->lowpassed, d->lp_len, 1);
|
|
if (sr < d->squelch_level) {
|
|
d->squelch_hits++;
|
|
for (i=0; i<d->lp_len; i++) {
|
|
d->lowpassed[i] = 0;
|
|
}
|
|
} else {
|
|
d->squelch_hits = 0;}
|
|
}
|
|
d->mode_demod(d); /* lowpassed -> result */
|
|
if (d->mode_demod == &raw_demod) {
|
|
return;
|
|
}
|
|
/* todo, fm noise squelch */
|
|
// use nicer filter here too?
|
|
if (d->post_downsample > 1) {
|
|
d->result_len = low_pass_simple(d->result, d->result_len, d->post_downsample);}
|
|
if (d->deemph) {
|
|
deemph_filter(d);}
|
|
if (d->dc_block) {
|
|
dc_block_filter(d);}
|
|
if (d->rate_out2 > 0) {
|
|
low_pass_real(d);
|
|
//arbitrary_resample(d->result, d->result, d->result_len, d->result_len * d->rate_out2 / d->rate_out);
|
|
}
|
|
}
|
|
|
|
static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
|
|
{
|
|
int i;
|
|
struct dongle_state *s = static_cast<dongle_state*>(ctx);
|
|
struct demod_state *d = s->demod_target;
|
|
|
|
if (exitflag) {
|
|
return;}
|
|
if (!ctx) {
|
|
return;}
|
|
if (s->mute) {
|
|
for (i=0; i<s->mute; i++) {
|
|
buf[i] = 127;}
|
|
s->mute = 0;
|
|
}
|
|
if (!s->offset_tuning) {
|
|
rotate_90(buf, len);}
|
|
for (i=0; i<(int)len; i++) {
|
|
s->buf16[i] = (int16_t)buf[i] - 127;}
|
|
pthread_rwlock_wrlock(&d->rw);
|
|
memcpy(d->lowpassed, s->buf16, 2*len);
|
|
d->lp_len = len;
|
|
pthread_rwlock_unlock(&d->rw);
|
|
safe_cond_signal(&d->ready, &d->ready_m);
|
|
}
|
|
|
|
static void *dongle_thread_fn(void *arg)
|
|
{
|
|
struct dongle_state *s = static_cast<dongle_state*>(arg);
|
|
rtlsdr_read_async(s->dev, rtlsdr_callback, s, 0, s->buf_len);
|
|
return 0;
|
|
}
|
|
|
|
static void *demod_thread_fn(void *arg)
|
|
{
|
|
struct demod_state *d = static_cast<demod_state*>(arg);
|
|
struct output_state *o = d->output_target;
|
|
while (!exitflag) {
|
|
safe_cond_wait(&d->ready, &d->ready_m);
|
|
pthread_rwlock_wrlock(&d->rw);
|
|
full_demod(d);
|
|
pthread_rwlock_unlock(&d->rw);
|
|
if (d->exit_flag) {
|
|
exitflag = 1;
|
|
}
|
|
if (d->squelch_level && d->squelch_hits > d->conseq_squelch) {
|
|
d->squelch_hits = d->conseq_squelch + 1; /* hair trigger */
|
|
safe_cond_signal(&controller.hop, &controller.hop_m);
|
|
continue;
|
|
}
|
|
pthread_rwlock_wrlock(&o->rw);
|
|
for (int i = 0; i < d->result_len; i++)
|
|
{
|
|
for (int j=0; j < bandwidth_multiplier; j++){
|
|
o->queue.push(d->result[i]);}
|
|
}
|
|
pthread_rwlock_unlock(&o->rw);
|
|
safe_cond_signal(&o->ready, &o->ready_m);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int nearest_gain(rtlsdr_dev_t *dev, int target_gain)
|
|
{
|
|
int i, r, err1, err2, count, nearest;
|
|
int* gains;
|
|
r = rtlsdr_set_tuner_gain_mode(dev, 1);
|
|
if (r < 0) {
|
|
fprintf (stderr, "WARNING: Failed to enable manual gain.\n");
|
|
return r;
|
|
}
|
|
count = rtlsdr_get_tuner_gains(dev, NULL);
|
|
if (count <= 0) {
|
|
return 0;
|
|
}
|
|
gains = static_cast<int*>(malloc(sizeof(int) * count));
|
|
count = rtlsdr_get_tuner_gains(dev, gains);
|
|
nearest = gains[0];
|
|
for (i=0; i<count; i++) {
|
|
err1 = abs(target_gain - nearest);
|
|
err2 = abs(target_gain - gains[i]);
|
|
if (err2 < err1) {
|
|
nearest = gains[i];
|
|
}
|
|
}
|
|
free(gains);
|
|
return nearest;
|
|
}
|
|
|
|
int verbose_set_frequency(rtlsdr_dev_t *dev, uint32_t frequency)
|
|
{
|
|
int r;
|
|
r = rtlsdr_set_center_freq(dev, frequency);
|
|
if (r < 0) {
|
|
fprintf (stderr, " (WARNING: Failed to set Center Frequency). \n");
|
|
} else {
|
|
fprintf (stderr, " (Center Frequency: %u Hz.) \n", frequency);
|
|
}
|
|
return r;
|
|
}
|
|
|
|
int verbose_set_sample_rate(rtlsdr_dev_t *dev, uint32_t samp_rate)
|
|
{
|
|
int r;
|
|
r = rtlsdr_set_sample_rate(dev, samp_rate);
|
|
if (r < 0) {
|
|
fprintf (stderr, "WARNING: Failed to set sample rate.\n");
|
|
} else {
|
|
fprintf (stderr, "Sampling at %u S/s.\n", samp_rate);
|
|
}
|
|
return r;
|
|
}
|
|
|
|
int verbose_direct_sampling(rtlsdr_dev_t *dev, int on)
|
|
{
|
|
int r;
|
|
r = rtlsdr_set_direct_sampling(dev, on);
|
|
if (r != 0) {
|
|
fprintf (stderr, "WARNING: Failed to set direct sampling mode.\n");
|
|
return r;
|
|
}
|
|
if (on == 0) {
|
|
fprintf (stderr, "Direct sampling mode disabled.\n");}
|
|
if (on == 1) {
|
|
fprintf (stderr, "Enabled direct sampling mode, input 1/I.\n");}
|
|
if (on == 2) {
|
|
fprintf (stderr, "Enabled direct sampling mode, input 2/Q.\n");}
|
|
return r;
|
|
}
|
|
|
|
int verbose_offset_tuning(rtlsdr_dev_t *dev)
|
|
{
|
|
int r;
|
|
r = rtlsdr_set_offset_tuning(dev, 1);
|
|
if (r != 0) {
|
|
fprintf (stderr, "WARNING: Failed to set offset tuning.\n");
|
|
} else {
|
|
fprintf (stderr, "Offset tuning mode enabled.\n");
|
|
}
|
|
return r;
|
|
}
|
|
|
|
int verbose_auto_gain(rtlsdr_dev_t *dev)
|
|
{
|
|
int r;
|
|
r = rtlsdr_set_tuner_gain_mode(dev, 0);
|
|
if (r != 0) {
|
|
fprintf (stderr, "WARNING: Failed to set tuner gain.\n");
|
|
} else {
|
|
fprintf (stderr, "Tuner gain set to automatic.\n");
|
|
}
|
|
return r;
|
|
}
|
|
|
|
int verbose_gain_set(rtlsdr_dev_t *dev, int gain)
|
|
{
|
|
int r;
|
|
r = rtlsdr_set_tuner_gain_mode(dev, 1);
|
|
if (r < 0) {
|
|
fprintf (stderr, "WARNING: Failed to enable manual gain.\n");
|
|
return r;
|
|
}
|
|
r = rtlsdr_set_tuner_gain(dev, gain);
|
|
if (r != 0) {
|
|
fprintf (stderr, "WARNING: Failed to set tuner gain.\n");
|
|
} else {
|
|
fprintf (stderr, "Tuner gain set to %0.2f dB.\n", gain/10.0);
|
|
}
|
|
return r;
|
|
}
|
|
|
|
int verbose_ppm_set(rtlsdr_dev_t *dev, int ppm_error)
|
|
{
|
|
int r;
|
|
if (ppm_error == 0) {
|
|
return 0;}
|
|
r = rtlsdr_set_freq_correction(dev, ppm_error);
|
|
if (r < 0) {
|
|
fprintf (stderr, "WARNING: Failed to set ppm error.\n");
|
|
} else {
|
|
fprintf (stderr, "Tuner error set to %i ppm.\n", ppm_error);
|
|
}
|
|
return r;
|
|
}
|
|
|
|
int verbose_reset_buffer(rtlsdr_dev_t *dev)
|
|
{
|
|
int r;
|
|
r = rtlsdr_reset_buffer(dev);
|
|
if (r < 0) {
|
|
fprintf (stderr, "WARNING: Failed to reset buffers.\n");}
|
|
return r;
|
|
}
|
|
|
|
static void optimal_settings(int freq, int rate)
|
|
{
|
|
UNUSED(rate);
|
|
|
|
// giant ball of hacks
|
|
// seems unable to do a single pass, 2:1
|
|
int capture_freq, capture_rate;
|
|
struct dongle_state *d = &dongle;
|
|
struct demod_state *dm = &demod;
|
|
struct controller_state *cs = &controller;
|
|
dm->downsample = (1000000 / dm->rate_in) + 1; //dm->rate_in is the rtl_bandwidth value
|
|
if (dm->downsample_passes) {
|
|
dm->downsample_passes = (int)log2(dm->downsample) + 1;
|
|
dm->downsample = 1 << dm->downsample_passes;
|
|
}
|
|
capture_freq = freq;
|
|
capture_rate = dm->downsample * dm->rate_in; //
|
|
if (!d->offset_tuning) {
|
|
capture_freq = freq + capture_rate/4;} //
|
|
capture_freq += cs->edge * dm->rate_in / 2;
|
|
dm->output_scale = (1<<15) / (128 * dm->downsample);
|
|
if (dm->output_scale < 1) {
|
|
dm->output_scale = 1;}
|
|
if (dm->mode_demod == &fm_demod) {
|
|
dm->output_scale = 1;}
|
|
d->freq = (uint32_t)capture_freq;
|
|
d->rate = (uint32_t)capture_rate;
|
|
// fprintf (stderr, "Capture Frequency: %i Rate: %i \n", capture_freq, capture_rate);
|
|
}
|
|
|
|
static void *controller_thread_fn(void *arg)
|
|
{
|
|
// thoughts for multiple dongles
|
|
// might be no good using a controller thread if retune/rate blocks
|
|
int i;
|
|
struct controller_state *s = static_cast<controller_state*>(arg);
|
|
|
|
if (s->wb_mode) {
|
|
for (i=0; i < s->freq_len; i++) {
|
|
s->freqs[i] += 16000;}
|
|
}
|
|
|
|
/* set up primary channel */
|
|
optimal_settings(s->freqs[0], demod.rate_in);
|
|
if (dongle.direct_sampling) {
|
|
verbose_direct_sampling(dongle.dev, 1);}
|
|
if (dongle.offset_tuning) {
|
|
verbose_offset_tuning(dongle.dev);}
|
|
|
|
/* Set the frequency */
|
|
verbose_set_frequency(dongle.dev, dongle.freq);
|
|
fprintf (stderr, "Oversampling input by: %ix.\n", demod.downsample);
|
|
fprintf (stderr, "Oversampling output by: %ix.\n", demod.post_downsample);
|
|
fprintf (stderr, "Buffer size: %0.2fms\n",
|
|
1000 * 0.5 * (float)ACTUAL_BUF_LENGTH / (float)dongle.rate);
|
|
|
|
/* Set the sample rate */
|
|
verbose_set_sample_rate(dongle.dev, dongle.rate);
|
|
fprintf (stderr, "Output at %u Hz.\n", demod.rate_in/demod.post_downsample);
|
|
|
|
while (!exitflag) {
|
|
safe_cond_wait(&s->hop, &s->hop_m);
|
|
if (s->freq_len <= 1) {
|
|
continue;}
|
|
/* hacky hopping */
|
|
s->freq_now = (s->freq_now + 1) % s->freq_len;
|
|
optimal_settings(s->freqs[s->freq_now], demod.rate_in);
|
|
rtlsdr_set_center_freq(dongle.dev, dongle.freq);
|
|
dongle.mute = BUFFER_DUMP;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void dongle_init(struct dongle_state *s)
|
|
{
|
|
s->rate = rtl_bandwidth;
|
|
s->gain = AUTO_GAIN; // tenths of a dB
|
|
s->mute = 0;
|
|
s->direct_sampling = 0;
|
|
s->offset_tuning = 0; //E4000 tuners only
|
|
s->demod_target = &demod;
|
|
}
|
|
|
|
void demod_init_ro2(struct demod_state *s)
|
|
{
|
|
s->rate_in = rtl_bandwidth;
|
|
s->rate_out = rtl_bandwidth;
|
|
s->squelch_level = 0;
|
|
s->conseq_squelch = 10;
|
|
s->terminate_on_squelch = 0;
|
|
s->squelch_hits = 11;
|
|
s->downsample_passes = 0;
|
|
s->comp_fir_size = 0;
|
|
s->prev_index = 0;
|
|
s->post_downsample = 1; //1 -- once this works, default = 4 -- doesn't work on the official rtl-sdr source code either
|
|
s->custom_atan = 0;
|
|
s->deemph = 0;
|
|
s->rate_out2 = rtl_bandwidth; // -1 flag for disabled -- this enables low_pass_real, seems to work okay
|
|
s->mode_demod = &fm_demod;
|
|
s->pre_j = s->pre_r = s->now_r = s->now_j = 0;
|
|
s->prev_lpr_index = 0;
|
|
s->deemph_a = 0;
|
|
s->now_lpr = 0;
|
|
s->dc_block = 1; //enabling by default, but offset tuning is also enabled, so center spike shouldn't be an issue
|
|
s->dc_avg = 0;
|
|
pthread_rwlock_init(&s->rw, NULL);
|
|
pthread_cond_init(&s->ready, NULL);
|
|
pthread_mutex_init(&s->ready_m, NULL);
|
|
s->output_target = &output;
|
|
}
|
|
|
|
void demod_init(struct demod_state *s)
|
|
{
|
|
s->rate_in = rtl_bandwidth;
|
|
s->rate_out = rtl_bandwidth;
|
|
s->squelch_level = 0;
|
|
s->conseq_squelch = 10;
|
|
s->terminate_on_squelch = 0;
|
|
s->squelch_hits = 11;
|
|
s->downsample_passes = 0;
|
|
s->comp_fir_size = 0;
|
|
s->prev_index = 0;
|
|
s->post_downsample = 1; //1 -- once this works, default = 4 -- doesn't work on the official rtl-sdr source code either
|
|
s->custom_atan = 0;
|
|
s->deemph = 0;
|
|
s->rate_out2 = -1; // -1 flag for disabled -- this enables low_pass_real, seems to work okay
|
|
s->mode_demod = &fm_demod;
|
|
s->pre_j = s->pre_r = s->now_r = s->now_j = 0;
|
|
s->prev_lpr_index = 0;
|
|
s->deemph_a = 0;
|
|
s->now_lpr = 0;
|
|
s->dc_block = 1; //enabling by default, but offset tuning is also enabled, so center spike shouldn't be an issue
|
|
s->dc_avg = 0;
|
|
pthread_rwlock_init(&s->rw, NULL);
|
|
pthread_cond_init(&s->ready, NULL);
|
|
pthread_mutex_init(&s->ready_m, NULL);
|
|
s->output_target = &output;
|
|
}
|
|
|
|
void demod_cleanup(struct demod_state *s)
|
|
{
|
|
pthread_rwlock_destroy(&s->rw);
|
|
pthread_cond_destroy(&s->ready);
|
|
pthread_mutex_destroy(&s->ready_m);
|
|
}
|
|
|
|
void output_init(struct output_state *s)
|
|
{
|
|
s->rate = rtl_bandwidth;
|
|
pthread_rwlock_init(&s->rw, NULL);
|
|
pthread_cond_init(&s->ready, NULL);
|
|
pthread_mutex_init(&s->ready_m, NULL);
|
|
}
|
|
|
|
void output_cleanup(struct output_state *s)
|
|
{
|
|
pthread_rwlock_destroy(&s->rw);
|
|
pthread_cond_destroy(&s->ready);
|
|
pthread_mutex_destroy(&s->ready_m);
|
|
}
|
|
|
|
void controller_init(struct controller_state *s)
|
|
{
|
|
s->freqs[0] = 446000000;
|
|
s->freq_len = 0;
|
|
s->edge = 0;
|
|
s->wb_mode = 0;
|
|
pthread_cond_init(&s->hop, NULL);
|
|
pthread_mutex_init(&s->hop_m, NULL);
|
|
}
|
|
|
|
void controller_cleanup(struct controller_state *s)
|
|
{
|
|
pthread_cond_destroy(&s->hop);
|
|
pthread_mutex_destroy(&s->hop_m);
|
|
}
|
|
|
|
void sanity_checks(void)
|
|
{
|
|
if (controller.freq_len == 0) {
|
|
fprintf (stderr, "Please specify a frequency.\n");
|
|
exit(1);
|
|
}
|
|
|
|
if (controller.freq_len >= FREQUENCIES_LIMIT) {
|
|
fprintf (stderr, "Too many channels, maximum %i.\n", FREQUENCIES_LIMIT);
|
|
exit(1);
|
|
}
|
|
|
|
if (controller.freq_len > 1 && demod.squelch_level == 0) {
|
|
fprintf (stderr, "Please specify a squelch level. Required for scanning multiple frequencies.\n");
|
|
exit(1);
|
|
}
|
|
|
|
}
|
|
|
|
//UDP remote stuff
|
|
static unsigned int chars_to_int(unsigned char* buf) {
|
|
|
|
int i;
|
|
unsigned int val = 0;
|
|
|
|
for(i=1; i<5; i++) {
|
|
val = val | ((buf[i]) << ((i-1)*8));
|
|
}
|
|
|
|
return val;
|
|
}
|
|
|
|
static void *socket_thread_fn(void *arg) {
|
|
UNUSED(arg);
|
|
|
|
int n;
|
|
int sockfd;
|
|
unsigned char buffer[5];
|
|
struct sockaddr_in serv_addr;
|
|
|
|
sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
|
|
|
|
if (sockfd < 0) {
|
|
perror("ERROR opening socket");
|
|
}
|
|
|
|
bzero((char *) &serv_addr, sizeof(serv_addr));
|
|
|
|
serv_addr.sin_family = AF_INET;
|
|
serv_addr.sin_addr.s_addr = INADDR_ANY;
|
|
serv_addr.sin_port = htons(port);
|
|
|
|
if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
|
|
perror("ERROR on binding");
|
|
}
|
|
|
|
bzero(buffer,5);
|
|
|
|
fprintf (stderr, "Main socket started! :-) Tuning enabled on UDP/%d \n", port);
|
|
|
|
int new_freq;
|
|
|
|
while((n = read(sockfd,buffer,5)) != 0) {
|
|
if(buffer[0] == 0) {
|
|
new_freq = chars_to_int(buffer);
|
|
dongle.freq = new_freq;
|
|
optimal_settings(new_freq, demod.rate_in);
|
|
rtlsdr_set_center_freq(dongle.dev, dongle.freq);
|
|
fprintf (stderr, "\nTuning to: %d [Hz] \n", new_freq);
|
|
}
|
|
|
|
|
|
}
|
|
|
|
close(sockfd);
|
|
return 0;
|
|
}
|
|
//UDP stuff end
|
|
|
|
void rtlsdr_sighandler()
|
|
{
|
|
fprintf (stderr, "Signal caught, exiting!\n");
|
|
rtlsdr_cancel_async(dongle.dev);
|
|
}
|
|
|
|
void open_rtlsdr_stream(dsd_opts *opts)
|
|
{
|
|
int r;
|
|
rtl_bandwidth = opts->rtl_bandwidth * 1000; //reverted back to straight value
|
|
bandwidth_multiplier = (bandwidth_divisor / rtl_bandwidth);
|
|
|
|
//this needs to be initted first, then we set the parameters
|
|
dongle_init(&dongle);
|
|
//init with low pass if decoding P25 or EDACS/Provoice
|
|
if (opts->frame_p25p1 == 1 || opts->frame_provoice == 1)
|
|
demod_init_ro2(&demod);
|
|
else demod_init(&demod);
|
|
output_init(&output);
|
|
controller_init(&controller);
|
|
|
|
if (opts->rtlsdr_center_freq > 0) {
|
|
controller.freqs[controller.freq_len] = opts->rtlsdr_center_freq;
|
|
controller.freq_len++;
|
|
}
|
|
|
|
if (opts->rtlsdr_ppm_error != 0) {
|
|
dongle.ppm_error = opts->rtlsdr_ppm_error;
|
|
fprintf (stderr, "Setting RTL PPM Error Set to %d\n", opts->rtlsdr_ppm_error);
|
|
}
|
|
|
|
dongle.dev_index = opts->rtl_dev_index;
|
|
// demod.squelch_level = opts->rtl_squelch_level; //no longer used here, used in framesync vc rms value under select conditions
|
|
fprintf (stderr, "Setting RTL Bandwidth to %d Hz\n", rtl_bandwidth);
|
|
// fprintf (stderr, "Setting RTL Sample Multiplier to %d\n", bandwidth_multiplier);
|
|
fprintf (stderr, "Setting RTL RMS Squelch Level to %d\n", opts->rtl_squelch_level);
|
|
if (opts->rtl_udp_port != 0) port = opts->rtl_udp_port; //set this here, only open socket thread if set
|
|
if (opts->rtl_gain_value > 0) {
|
|
dongle.gain = opts->rtl_gain_value * 10; //multiple by ten to make it consitent with the way rtl_fm works
|
|
}
|
|
volume_multiplier = opts->rtl_volume_multiplier;
|
|
// fprintf (stderr, "Setting RTL Volume Multiplier to %d\n", volume_multiplier);
|
|
|
|
/* quadruple sample_rate to limit to Δθ to ±π/2 */
|
|
demod.rate_in *= demod.post_downsample;
|
|
|
|
if (!output.rate) output.rate = demod.rate_out;
|
|
|
|
sanity_checks();
|
|
|
|
if (controller.freq_len > 1) demod.terminate_on_squelch = 0;
|
|
|
|
ACTUAL_BUF_LENGTH = lcm_post[demod.post_downsample] * DEFAULT_BUF_LENGTH;
|
|
|
|
r = rtlsdr_open(&dongle.dev, (uint32_t)dongle.dev_index);
|
|
if (r < 0)
|
|
{
|
|
fprintf (stderr, "Failed to open rtlsdr device %d.\n", dongle.dev_index);
|
|
exit(1);
|
|
} else {
|
|
fprintf (stderr, "Using RTLSDR Device Index: %d. \n", dongle.dev_index);
|
|
}
|
|
|
|
if (demod.deemph) {
|
|
demod.deemph_a = (int)round(1.0/((1.0-exp(-1.0/(demod.rate_out * 75e-6)))));
|
|
}
|
|
|
|
/* Set the tuner gain */
|
|
if (dongle.gain == AUTO_GAIN) {
|
|
verbose_auto_gain(dongle.dev);
|
|
fprintf (stderr, "Setting RTL Autogain. \n");
|
|
} else {
|
|
dongle.gain = nearest_gain(dongle.dev, dongle.gain);
|
|
verbose_gain_set(dongle.dev, dongle.gain);
|
|
// fprintf (stderr, "Setting RTL Nearest Gain to %d. \n", dongle.gain); //seems to be working now
|
|
}
|
|
|
|
verbose_ppm_set(dongle.dev, dongle.ppm_error);
|
|
|
|
/* Reset endpoint before we start reading from it (mandatory) */
|
|
verbose_reset_buffer(dongle.dev);
|
|
|
|
pthread_create(&controller.thread, NULL, controller_thread_fn, (void*)(&controller));
|
|
usleep(100000);
|
|
pthread_create(&demod.thread, NULL, demod_thread_fn, (void*)(&demod));
|
|
pthread_create(&dongle.thread, NULL, dongle_thread_fn, (void*)(&dongle));
|
|
//only create socket thread IF user specified (for legacy uses), else don't use it
|
|
if (port != 0) pthread_create(&socket_freq, NULL, socket_thread_fn, (void *)(&controller));
|
|
}
|
|
|
|
void cleanup_rtlsdr_stream()
|
|
{
|
|
fprintf (stderr, "cleaning up...\n");
|
|
rtlsdr_cancel_async(dongle.dev);
|
|
pthread_join(dongle.thread, NULL);
|
|
safe_cond_signal(&demod.ready, &demod.ready_m);
|
|
pthread_join(demod.thread, NULL);
|
|
safe_cond_signal(&output.ready, &output.ready_m);
|
|
safe_cond_signal(&controller.hop, &controller.hop_m);
|
|
pthread_join(controller.thread, NULL);
|
|
|
|
//dongle_cleanup(&dongle);
|
|
demod_cleanup(&demod);
|
|
output_cleanup(&output);
|
|
controller_cleanup(&controller);
|
|
|
|
rtlsdr_close(dongle.dev);
|
|
}
|
|
|
|
//original for safe keeping
|
|
// void get_rtlsdr_sample(int16_t *sample, dsd_opts * opts, dsd_state * state)
|
|
// {
|
|
// if (output.queue.empty())
|
|
// {
|
|
// safe_cond_wait(&output.ready, &output.ready_m);
|
|
// }
|
|
// pthread_rwlock_wrlock(&output.rw);
|
|
// *sample = output.queue.front() * volume_multiplier;
|
|
// output.queue.pop();
|
|
// pthread_rwlock_unlock(&output.rw);
|
|
// }
|
|
|
|
//find way to modify this function to allow hopping (tuning) while squelched and send 0 sample?
|
|
int get_rtlsdr_sample(int16_t *sample, dsd_opts * opts, dsd_state * state)
|
|
{
|
|
UNUSED2(opts, state);
|
|
|
|
while (output.queue.empty())
|
|
{
|
|
struct timespec ts;
|
|
clock_gettime(CLOCK_REALTIME, &ts);
|
|
ts.tv_nsec += 10e6;
|
|
|
|
pthread_mutex_lock(&output.ready_m);
|
|
pthread_cond_timedwait(&output.ready, &output.ready_m, &ts);
|
|
pthread_mutex_unlock(&output.ready_m);
|
|
|
|
if (exitflag)
|
|
{
|
|
return -1;
|
|
}
|
|
}
|
|
pthread_rwlock_wrlock(&output.rw);
|
|
*sample = output.queue.front() * volume_multiplier;
|
|
output.queue.pop();
|
|
pthread_rwlock_unlock(&output.rw);
|
|
return 0;
|
|
}
|
|
|
|
//function may lag since it isn't running as its own thread
|
|
void rtl_dev_tune(dsd_opts * opts, long int frequency)
|
|
{
|
|
int r;
|
|
if (opts->payload == 1)
|
|
fprintf (stderr, "\nTuning to %lu Hz.", frequency);
|
|
dongle.freq = opts->rtlsdr_center_freq = frequency;
|
|
optimal_settings(dongle.freq, demod.rate_in);
|
|
if (opts->payload == 1)
|
|
fprintf (stderr, " (Center Frequency: %u Hz.) \n", dongle.freq);
|
|
r = rtlsdr_set_center_freq(dongle.dev, dongle.freq);
|
|
if (r < 0)
|
|
fprintf (stderr, " (WARNING: Failed to set Center Frequency %u). \n", dongle.freq);
|
|
|
|
pthread_rwlock_wrlock(&output.rw); //prevent possible segfault when cleaning the queue
|
|
rtl_clean_queue();
|
|
pthread_rwlock_unlock(&output.rw); //resume
|
|
|
|
}
|
|
|
|
//return RMS value (root means square) power level -- used as soft squelch inside of framesync
|
|
long int rtl_return_rms()
|
|
{
|
|
long int sr = 0;
|
|
// #ifdef __arm__
|
|
// sr = 100;
|
|
// #else
|
|
//debug -- on main machine, lp_len is around 6420, so this probably contributes to very high CPU usage
|
|
// fprintf (stderr, "LP_LEN: %d \n", demod.lp_len);
|
|
//I've found that just using a sample size of 160 will give us a good approximation without killing the CPU
|
|
// sr = rms(demod.lowpassed, demod.lp_len, 1);
|
|
sr = rms(demod.lowpassed, 160, 1); //I wonder what a reasonable value would be for #2 (input len) there
|
|
// #endif
|
|
return (sr);
|
|
}
|
|
|
|
//simple function to clear the rtl sample queue when tuning and during other events (ncurses menu open/close)
|
|
void rtl_clean_queue()
|
|
{
|
|
//insert method to clear the entire queue to prevent sample 'lag'
|
|
std::queue<int16_t> empty; //create an empty queue
|
|
std::swap( output.queue, empty ); //swap in empty queue to effectively zero out current queue
|
|
} |