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This commit is contained in:
Bastian Bloessl
2013-10-10 11:06:36 +02:00
parent b0503d5fa3
commit 58ed53a5d5
42 changed files with 2848 additions and 362 deletions
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lib/ofdm_sync_long.cc
+43 -37
View File
@@ -15,40 +15,41 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <ieee802-11/ofdm_sync_long.h>
#include "utils.h"
#include <gnuradio/io_signature.h>
#include <gnuradio/filter/fir_filter.h>
#include <gnuradio/fft/fft.h>
#include <list>
#include <tuple>
#include <iostream>
using namespace gr::ieee802_11;
using namespace std;
class ofdm_sync_long_impl : public ofdm_sync_long {
#define dout d_debug && std::cout
public:
ofdm_sync_long_impl(unsigned int sync_lenght, unsigned int freq_est, bool debug) : block("ofdm_sync_long",
ofdm_sync_long_impl(unsigned int sync_length, bool log, bool debug) : block("ofdm_sync_long",
gr::io_signature::make2(2, 2, sizeof(gr_complex), sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(gr_complex))),
d_log(log),
d_debug(debug),
d_offset(0),
d_freq_est(0),
d_state(SYNC),
SYNC_LENGTH(sync_lenght),
FREQ_EST(freq_est) {
SYNC_LENGTH(sync_length) {
set_tag_propagation_policy(block::TPP_DONT);
d_fir = new gr::filter::kernel::fir_filter_ccc(1, LONG);
d_correlation = gr::fft::malloc_complex(8192);
d_freq_est_buf = static_cast<gr_complex*>(std::malloc(sync_length * sizeof(gr_complex)));
}
~ofdm_sync_long_impl(){
delete d_fir;
gr::fft::free(d_correlation);
free(d_freq_est_buf);
}
int general_work (int noutput, gr_vector_int& ninput_items,
@@ -93,9 +94,8 @@ int general_work (int noutput, gr_vector_int& ninput_items,
while(i + 63 < ninput) {
if(d_offset < FREQ_EST) {
d_freq_est += in[i] * conj(in[i + 16]);
}
d_freq_est += in[i] * conj(in[i + 16]);
d_freq_est_buf[d_offset] = d_freq_est;
d_cor.push_back(std::tuple<double, int>(abs(d_correlation[i]), d_offset));
@@ -104,8 +104,12 @@ int general_work (int noutput, gr_vector_int& ninput_items,
if(d_offset == SYNC_LENGTH) {
search_frame_start();
d_freq_est = d_freq_est_buf[std::max<int>(0, d_frame_start - 160 - 17)];
d_offset = 0;
d_state = COPY;
mylog(boost::format("frame at %1% - freq_est (20M): %2%") % d_frame_start
% ((arg(d_freq_est) / 16) * 20e6 / (2 * M_PI)));
break;
}
}
@@ -160,7 +164,7 @@ int general_work (int noutput, gr_vector_int& ninput_items,
break;
default:
assert(false);
std::runtime_error("bad state");
break;
}
@@ -173,6 +177,8 @@ int general_work (int noutput, gr_vector_int& ninput_items,
void forecast (int noutput_items, gr_vector_int &ninput_items_required) {
// in sync state we need at least a symbol to correlate
// with the pattern
if(d_state == SYNC) {
ninput_items_required[0] = 64;
ninput_items_required[1] = 64;
@@ -181,39 +187,38 @@ void forecast (int noutput_items, gr_vector_int &ninput_items_required) {
ninput_items_required[0] = noutput_items;
ninput_items_required[1] = noutput_items;
}
0 && dout << "LONG forecast noutput_items: " << noutput_items
<< " state: " << d_state
<< " req[0] " << ninput_items_required[0]
<< " req[1] " << ninput_items_required[1]
<< std::endl;
}
void search_frame_start() {
// sort list (highest correlation first)
assert(d_cor.size() == SYNC_LENGTH);
d_cor.sort();
d_cor.reverse();
std::list<std::tuple<double, int>>::iterator it = d_cor.begin();
int m1 = std::get<1>(*it);
it++;
int m2 = std::get<1>(*it);
it++;
int m3 = std::get<1>(*it);
int m = std::max(m1, std::max(m2, m3));
d_frame_start = m + 64;
dout << "d_frame_start " << d_frame_start << std::endl;
dout << "peaks " << m1 << " " << m2 << " " << m3 << std::endl;
//for(it = d_cor.begin(); it != d_cor.end(); it++) {
//std::cout << std::get<0>(*it) << " " << std::get<1>(*it) << std::endl;
//}
// copy list in vector for nicer access
vector<tuple<double, int>> vec(d_cor.begin(), d_cor.end());
d_cor.clear();
// in case we don't find anything use SYNC_LENGTH
d_frame_start = SYNC_LENGTH;
for(int i = 0; i < 3; i++) {
for(int k = i + 1; k < 4; k++) {
int diff = abs(get<1>(vec[i]) - get<1>(vec[k]));
if(diff == 64) {
d_frame_start = max(get<1>(vec[i]), get<1>(vec[k])) + 64;
// nice match found, return immediately
return;
// TODO: check if these offsets make sense
} else if(diff == 63) {
d_frame_start = max(get<1>(vec[i]), get<1>(vec[k])) + 63;
} else if(diff = 65) {
d_frame_start = max(get<1>(vec[i]), get<1>(vec[k])) + 64;
}
}
}
}
private:
@@ -222,20 +227,21 @@ private:
int d_frame_start;
gr_complex d_freq_est;
gr_complex *d_correlation;
gr_complex *d_freq_est_buf;
std::list<std::tuple<double, int>> d_cor;
std::vector<gr::tag_t> d_tags;
gr::filter::kernel::fir_filter_ccc *d_fir;
const bool d_log;
const bool d_debug;
const int SYNC_LENGTH;
const int FREQ_EST;
static const std::vector<gr_complex> LONG;
};
ofdm_sync_long::sptr
ofdm_sync_long::make(unsigned int sync_length, unsigned int freq_est, bool debug) {
return gnuradio::get_initial_sptr(new ofdm_sync_long_impl(sync_length, freq_est, debug));
ofdm_sync_long::make(unsigned int sync_length, bool log, bool debug) {
return gnuradio::get_initial_sptr(new ofdm_sync_long_impl(sync_length, log, debug));
}
const std::vector<gr_complex> ofdm_sync_long_impl::LONG = {