gr-satnogs/lib/waterfall_sink_impl.cc

304 lines
9.4 KiB
C++

/* -*- c++ -*- */
/*
* gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
*
* Copyright (C) 2017,2019 Libre Space Foundation <http://libre.space>
*
* 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 3 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/>.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gnuradio/io_signature.h>
#include "waterfall_sink_impl.h"
#include <satnogs/log.h>
#include <satnogs/utils.h>
#include <satnogs/date.h>
namespace gr {
namespace satnogs {
waterfall_sink::sptr
waterfall_sink::make(float samp_rate, float center_freq, float rps,
size_t fft_size, const std::string &filename, int mode)
{
return gnuradio::get_initial_sptr(
new waterfall_sink_impl(samp_rate, center_freq, rps, fft_size, filename,
mode));
}
/*
* The private constructor
*/
waterfall_sink_impl::waterfall_sink_impl(float samp_rate, float center_freq,
float rps, size_t fft_size,
const std::string &filename,
int mode) :
gr::sync_block("waterfall_sink",
gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(0, 0, 0)),
d_samp_rate(samp_rate),
d_center_freq(center_freq),
d_fft_size(fft_size),
d_mode((wf_mode_t) mode),
d_refresh((d_samp_rate / fft_size) / rps),
d_fft_cnt(0),
d_fft_shift((size_t)(ceil(fft_size / 2.0))),
d_samples_cnt(0),
d_fft(fft_size)
{
const int alignment_multiple = volk_get_alignment()
/ (fft_size * sizeof(gr_complex));
set_alignment(std::max(1, alignment_multiple));
set_output_multiple(fft_size);
d_shift_buffer = (gr_complex *) volk_malloc(fft_size * sizeof(gr_complex),
volk_get_alignment());
if (!d_shift_buffer) {
LOG_ERROR("Could not allocate aligned memory");
throw std::runtime_error("Could not allocate aligned memory");
}
d_hold_buffer = (float *) volk_malloc(fft_size * sizeof(gr_complex),
volk_get_alignment());
if (!d_hold_buffer) {
LOG_ERROR("Could not allocate aligned memory");
throw std::runtime_error("Could not allocate aligned memory");
}
memset(d_hold_buffer, 0, fft_size * sizeof(gr_complex));
d_tmp_buffer = (float *) volk_malloc(fft_size * sizeof(float),
volk_get_alignment());
if (!d_tmp_buffer) {
LOG_ERROR("Could not allocate aligned memory");
throw std::runtime_error("Could not allocate aligned memory");
}
d_fos.open(filename, std::ios::binary | std::ios::trunc);
if (d_fos.fail()) {
throw std::runtime_error("Could not create file for writing");
}
}
bool
waterfall_sink_impl::start()
{
/*
* Append header for proper plotting. We do it on the start() to reduce
* as much as possible the delay between the start of the observation tagging
* and the fist invocation of the work() method.
*/
apply_header();
return true;
}
/*
* Our virtual destructor.
*/
waterfall_sink_impl::~waterfall_sink_impl()
{
d_fos.close();
volk_free(d_shift_buffer);
volk_free(d_hold_buffer);
volk_free(d_tmp_buffer);
}
int
waterfall_sink_impl::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
const gr_complex *in = (const gr_complex *) input_items[0];
size_t n_fft = ((size_t) noutput_items / d_fft_size);
switch (d_mode) {
case WATERFALL_MODE_DECIMATION:
compute_decimation(in, n_fft);
break;
case WATERFALL_MODE_MAX_HOLD:
compute_max_hold(in, n_fft);
break;
case WATERFALL_MODE_MEAN:
compute_mean(in, n_fft);
break;
default:
LOG_ERROR("Wrong waterfall mode");
throw std::runtime_error("Wrong waterfall mode");
return -1;
}
return n_fft * d_fft_size;
}
void
waterfall_sink_impl::compute_decimation(const gr_complex *in, size_t n_fft)
{
size_t i;
gr_complex *fft_in;
for (i = 0; i < n_fft; i++) {
d_fft_cnt++;
if (d_fft_cnt == d_refresh) {
fft_in = d_fft.get_inbuf();
memcpy(fft_in, in + i * d_fft_size, d_fft_size * sizeof(gr_complex));
d_fft.execute();
/* Perform FFT shift */
memcpy(d_shift_buffer, &d_fft.get_outbuf()[d_fft_shift],
sizeof(gr_complex) * (d_fft_size - d_fft_shift));
memcpy(&d_shift_buffer[d_fft_size - d_fft_shift],
&d_fft.get_outbuf()[0], sizeof(gr_complex) * d_fft_shift);
/* Compute the energy in dB */
volk_32fc_s32f_x2_power_spectral_density_32f(d_hold_buffer,
d_shift_buffer,
(float) d_fft_size, 1.0,
d_fft_size);
/* Write the result to the file */
write_timestamp();
d_fos.write((char *) d_hold_buffer, d_fft_size * sizeof(float));
d_fft_cnt = 0;
}
d_samples_cnt += d_fft_size;
}
}
void
waterfall_sink_impl::compute_max_hold(const gr_complex *in, size_t n_fft)
{
size_t i;
size_t j;
gr_complex *fft_in;
for (i = 0; i < n_fft; i++) {
fft_in = d_fft.get_inbuf();
memcpy(fft_in, in + i * d_fft_size, d_fft_size * sizeof(gr_complex));
d_fft.execute();
/* Perform FFT shift */
memcpy(d_shift_buffer, &d_fft.get_outbuf()[d_fft_shift],
sizeof(gr_complex) * (d_fft_size - d_fft_shift));
memcpy(&d_shift_buffer[d_fft_size - d_fft_shift], &d_fft.get_outbuf()[0],
sizeof(gr_complex) * d_fft_shift);
/* Normalization factor */
volk_32fc_s32fc_multiply_32fc(d_shift_buffer, d_shift_buffer,
1.0 / d_fft_size, d_fft_size);
/* Compute the mag^2 */
volk_32fc_magnitude_squared_32f(d_tmp_buffer, d_shift_buffer, d_fft_size);
/* Max hold */
volk_32f_x2_max_32f(d_hold_buffer, d_hold_buffer, d_tmp_buffer,
d_fft_size);
d_fft_cnt++;
if (d_fft_cnt == d_refresh) {
/* Compute the energy in dB */
for (j = 0; j < d_fft_size; j++) {
d_hold_buffer[j] = 10.0 * log10f(d_hold_buffer[j] + 1.0e-20);
}
/* Write the result to the file */
write_timestamp();
d_fos.write((char *) d_hold_buffer, d_fft_size * sizeof(float));
/* Reset */
d_fft_cnt = 0;
memset(d_hold_buffer, 0, d_fft_size * sizeof(float));
}
d_samples_cnt += d_fft_size;
}
}
void
waterfall_sink_impl::apply_header()
{
header_t h;
memset(h.start_time, 0, 32);
std::chrono::system_clock::time_point tp = std::chrono::system_clock::now();
d_start = tp;
std::string s = date::format("%FT%TZ",
date::floor<std::chrono::microseconds> (tp));
std::strncpy(h.start_time, s.c_str(), 32);
/* Before writing to the file convert all values to Network Byte Order */
h.fft_size = htonl(d_fft_size);
h.samp_rate = htonl(d_samp_rate);
h.nfft_per_row = htonl(d_refresh);
uint32_t tmp = htonl(*((uint32_t *) &d_center_freq));
memcpy(&h.center_freq, &tmp, sizeof(uint32_t));
h.center_freq = *((float *) &tmp);
h.endianness = !(1 == htonl(1));
/*
* Write the header. Make a dummy serialization to avoid padding and
* alignment issues
*/
d_fos.write(h.start_time, 32);
d_fos.write((char *)&h.fft_size, sizeof(uint32_t));
d_fos.write((char *)&h.samp_rate, sizeof(uint32_t));
d_fos.write((char *)&h.nfft_per_row, sizeof(uint32_t));
d_fos.write((char *)&h.center_freq, sizeof(float));
d_fos.write((char *)&h.endianness, sizeof(uint32_t));
}
void
waterfall_sink_impl::write_timestamp()
{
std::chrono::system_clock::time_point tp = std::chrono::system_clock::now();
int64_t x = std::chrono::duration_cast<std::chrono::microseconds> (
tp - d_start).count();
d_fos.write((char *)&x, sizeof(int64_t));
}
void
waterfall_sink_impl::compute_mean(const gr_complex *in, size_t n_fft)
{
size_t i;
gr_complex *fft_in;
for (i = 0; i < n_fft; i++) {
fft_in = d_fft.get_inbuf();
memcpy(fft_in, in + i * d_fft_size, d_fft_size * sizeof(gr_complex));
d_fft.execute();
/* Perform FFT shift */
memcpy(d_shift_buffer, &d_fft.get_outbuf()[d_fft_shift],
sizeof(gr_complex) * (d_fft_size - d_fft_shift));
memcpy(&d_shift_buffer[d_fft_size - d_fft_shift], &d_fft.get_outbuf()[0],
sizeof(gr_complex) * d_fft_shift);
/* Accumulate the complex numbers */
volk_32f_x2_add_32f(d_hold_buffer, d_hold_buffer, (float *) d_shift_buffer,
2 * d_fft_size);
d_fft_cnt++;
if (d_fft_cnt == d_refresh) {
/*
* Compute the energy in dB performing the proper normalization
* before any dB calculation, emulating the mean
*/
volk_32fc_s32f_x2_power_spectral_density_32f(
d_hold_buffer, (gr_complex *) d_hold_buffer,
(float) d_fft_cnt * d_fft_size, 1.0, d_fft_size);
/* Write the result to the file */
write_timestamp();
d_fos.write((char *) d_hold_buffer, d_fft_size * sizeof(float));
/* Reset */
d_fft_cnt = 0;
memset(d_hold_buffer, 0, 2 * d_fft_size * sizeof(float));
}
d_samples_cnt += d_fft_size;
}
}
} /* namespace satnogs */
} /* namespace gr */