summaryrefslogtreecommitdiff
path: root/gr-digital/lib/digital_ofdm_frame_sink.cc
diff options
context:
space:
mode:
Diffstat (limited to 'gr-digital/lib/digital_ofdm_frame_sink.cc')
-rw-r--r--gr-digital/lib/digital_ofdm_frame_sink.cc405
1 files changed, 0 insertions, 405 deletions
diff --git a/gr-digital/lib/digital_ofdm_frame_sink.cc b/gr-digital/lib/digital_ofdm_frame_sink.cc
deleted file mode 100644
index f8fb1bbb1d..0000000000
--- a/gr-digital/lib/digital_ofdm_frame_sink.cc
+++ /dev/null
@@ -1,405 +0,0 @@
-/* -*- c++ -*- */
-/*
- * Copyright 2007,2008,2010,2011 Free Software Foundation, Inc.
- *
- * This file is part of GNU Radio
- *
- * GNU Radio 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, or (at your option)
- * any later version.
- *
- * GNU Radio 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 GNU Radio; see the file COPYING. If not, write to
- * the Free Software Foundation, Inc., 51 Franklin Street,
- * Boston, MA 02110-1301, USA.
- */
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <digital_ofdm_frame_sink.h>
-#include <gr_io_signature.h>
-#include <gr_expj.h>
-#include <gr_math.h>
-#include <math.h>
-#include <cstdio>
-#include <stdexcept>
-#include <iostream>
-#include <string.h>
-
-#define VERBOSE 0
-
-inline void
-digital_ofdm_frame_sink::enter_search()
-{
- if (VERBOSE)
- fprintf(stderr, "@ enter_search\n");
-
- d_state = STATE_SYNC_SEARCH;
-
-}
-
-inline void
-digital_ofdm_frame_sink::enter_have_sync()
-{
- if (VERBOSE)
- fprintf(stderr, "@ enter_have_sync\n");
-
- d_state = STATE_HAVE_SYNC;
-
- // clear state of demapper
- d_byte_offset = 0;
- d_partial_byte = 0;
-
- d_header = 0;
- d_headerbytelen_cnt = 0;
-
- // Resetting PLL
- d_freq = 0.0;
- d_phase = 0.0;
- fill(d_dfe.begin(), d_dfe.end(), gr_complex(1.0,0.0));
-}
-
-inline void
-digital_ofdm_frame_sink::enter_have_header()
-{
- d_state = STATE_HAVE_HEADER;
-
- // header consists of two 16-bit shorts in network byte order
- // payload length is lower 12 bits
- // whitener offset is upper 4 bits
- d_packetlen = (d_header >> 16) & 0x0fff;
- d_packet_whitener_offset = (d_header >> 28) & 0x000f;
- d_packetlen_cnt = 0;
-
- if (VERBOSE)
- fprintf(stderr, "@ enter_have_header (payload_len = %d) (offset = %d)\n",
- d_packetlen, d_packet_whitener_offset);
-}
-
-
-unsigned char digital_ofdm_frame_sink::slicer(const gr_complex x)
-{
- unsigned int table_size = d_sym_value_out.size();
- unsigned int min_index = 0;
- float min_euclid_dist = norm(x - d_sym_position[0]);
- float euclid_dist = 0;
-
- for (unsigned int j = 1; j < table_size; j++){
- euclid_dist = norm(x - d_sym_position[j]);
- if (euclid_dist < min_euclid_dist){
- min_euclid_dist = euclid_dist;
- min_index = j;
- }
- }
- return d_sym_value_out[min_index];
-}
-
-unsigned int digital_ofdm_frame_sink::demapper(const gr_complex *in,
- unsigned char *out)
-{
- unsigned int i=0, bytes_produced=0;
- gr_complex carrier;
-
- carrier=gr_expj(d_phase);
-
- gr_complex accum_error = 0.0;
- //while(i < d_occupied_carriers) {
- while(i < d_subcarrier_map.size()) {
- if(d_nresid > 0) {
- d_partial_byte |= d_resid;
- d_byte_offset += d_nresid;
- d_nresid = 0;
- d_resid = 0;
- }
-
- //while((d_byte_offset < 8) && (i < d_occupied_carriers)) {
- while((d_byte_offset < 8) && (i < d_subcarrier_map.size())) {
- //gr_complex sigrot = in[i]*carrier*d_dfe[i];
- gr_complex sigrot = in[d_subcarrier_map[i]]*carrier*d_dfe[i];
-
- if(d_derotated_output != NULL){
- d_derotated_output[i] = sigrot;
- }
-
- unsigned char bits = slicer(sigrot);
-
- gr_complex closest_sym = d_sym_position[bits];
-
- accum_error += sigrot * conj(closest_sym);
-
- // FIX THE FOLLOWING STATEMENT
- if (norm(sigrot)> 0.001) d_dfe[i] += d_eq_gain*(closest_sym/sigrot-d_dfe[i]);
-
- i++;
-
- if((8 - d_byte_offset) >= d_nbits) {
- d_partial_byte |= bits << (d_byte_offset);
- d_byte_offset += d_nbits;
- }
- else {
- d_nresid = d_nbits-(8-d_byte_offset);
- int mask = ((1<<(8-d_byte_offset))-1);
- d_partial_byte |= (bits & mask) << d_byte_offset;
- d_resid = bits >> (8-d_byte_offset);
- d_byte_offset += (d_nbits - d_nresid);
- }
- //printf("demod symbol: %.4f + j%.4f bits: %x partial_byte: %x byte_offset: %d resid: %x nresid: %d\n",
- // in[i-1].real(), in[i-1].imag(), bits, d_partial_byte, d_byte_offset, d_resid, d_nresid);
- }
-
- if(d_byte_offset == 8) {
- //printf("demod byte: %x \n\n", d_partial_byte);
- out[bytes_produced++] = d_partial_byte;
- d_byte_offset = 0;
- d_partial_byte = 0;
- }
- }
- //std::cerr << "accum_error " << accum_error << std::endl;
-
- float angle = arg(accum_error);
-
- d_freq = d_freq - d_freq_gain*angle;
- d_phase = d_phase + d_freq - d_phase_gain*angle;
- if (d_phase >= 2*M_PI) d_phase -= 2*M_PI;
- if (d_phase <0) d_phase += 2*M_PI;
-
- //if(VERBOSE)
- // std::cerr << angle << "\t" << d_freq << "\t" << d_phase << "\t" << std::endl;
-
- return bytes_produced;
-}
-
-
-digital_ofdm_frame_sink_sptr
-digital_make_ofdm_frame_sink(const std::vector<gr_complex> &sym_position,
- const std::vector<unsigned char> &sym_value_out,
- gr_msg_queue_sptr target_queue, unsigned int occupied_carriers,
- float phase_gain, float freq_gain)
-{
- return gnuradio::get_initial_sptr(new digital_ofdm_frame_sink(sym_position, sym_value_out,
- target_queue, occupied_carriers,
- phase_gain, freq_gain));
-}
-
-
-digital_ofdm_frame_sink::digital_ofdm_frame_sink(const std::vector<gr_complex> &sym_position,
- const std::vector<unsigned char> &sym_value_out,
- gr_msg_queue_sptr target_queue, unsigned int occupied_carriers,
- float phase_gain, float freq_gain)
- : gr_sync_block ("ofdm_frame_sink",
- gr_make_io_signature2 (2, 2, sizeof(gr_complex)*occupied_carriers, sizeof(char)),
- gr_make_io_signature (1, 1, sizeof(gr_complex)*occupied_carriers)),
- d_target_queue(target_queue), d_occupied_carriers(occupied_carriers),
- d_byte_offset(0), d_partial_byte(0),
- d_resid(0), d_nresid(0),d_phase(0),d_freq(0),d_phase_gain(phase_gain),d_freq_gain(freq_gain),
- d_eq_gain(0.05)
-{
- std::string carriers = "FE7F";
-
- // A bit hacky to fill out carriers to occupied_carriers length
- int diff = (d_occupied_carriers - 4*carriers.length());
- while(diff > 7) {
- carriers.insert(0, "f");
- carriers.insert(carriers.length(), "f");
- diff -= 8;
- }
-
- // if there's extras left to be processed
- // divide remaining to put on either side of current map
- // all of this is done to stick with the concept of a carrier map string that
- // can be later passed by the user, even though it'd be cleaner to just do this
- // on the carrier map itself
- int diff_left=0;
- int diff_right=0;
-
- // dictionary to convert from integers to ascii hex representation
- char abc[16] = {'0', '1', '2', '3', '4', '5', '6', '7',
- '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
- if(diff > 0) {
- char c[2] = {0,0};
-
- diff_left = (int)ceil((float)diff/2.0f); // number of carriers to put on the left side
- c[0] = abc[(1 << diff_left) - 1]; // convert to bits and move to ASCI integer
- carriers.insert(0, c);
-
- diff_right = diff - diff_left; // number of carriers to put on the right side
- c[0] = abc[0xF^((1 << diff_right) - 1)]; // convert to bits and move to ASCI integer
- carriers.insert(carriers.length(), c);
- }
-
- // It seemed like such a good idea at the time...
- // because we are only dealing with the occupied_carriers
- // at this point, the diff_left in the following compensates
- // for any offset from the 0th carrier introduced
- unsigned int i,j,k;
- for(i = 0; i < (d_occupied_carriers/4)+diff_left; i++) {
- char c = carriers[i];
- for(j = 0; j < 4; j++) {
- k = (strtol(&c, NULL, 16) >> (3-j)) & 0x1;
- if(k) {
- d_subcarrier_map.push_back(4*i + j - diff_left);
- }
- }
- }
-
- // make sure we stay in the limit currently imposed by the occupied_carriers
- if(d_subcarrier_map.size() > d_occupied_carriers) {
- throw std::invalid_argument("digital_ofdm_mapper_bcv: subcarriers allocated exceeds size of occupied carriers");
- }
-
- d_bytes_out = new unsigned char[d_occupied_carriers];
- d_dfe.resize(occupied_carriers);
- fill(d_dfe.begin(), d_dfe.end(), gr_complex(1.0,0.0));
-
- set_sym_value_out(sym_position, sym_value_out);
-
- enter_search();
-}
-
-digital_ofdm_frame_sink::~digital_ofdm_frame_sink ()
-{
- delete [] d_bytes_out;
-}
-
-bool
-digital_ofdm_frame_sink::set_sym_value_out(const std::vector<gr_complex> &sym_position,
- const std::vector<unsigned char> &sym_value_out)
-{
- if (sym_position.size() != sym_value_out.size())
- return false;
-
- if (sym_position.size()<1)
- return false;
-
- d_sym_position = sym_position;
- d_sym_value_out = sym_value_out;
- d_nbits = (unsigned long)ceil(log10(float(d_sym_value_out.size())) / log10(2.0));
-
- return true;
-}
-
-
-int
-digital_ofdm_frame_sink::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];
- const char *sig = (const char *) input_items[1];
- unsigned int j = 0;
- unsigned int bytes=0;
-
- // If the output is connected, send it the derotated symbols
- if(output_items.size() >= 1)
- d_derotated_output = (gr_complex *)output_items[0];
- else
- d_derotated_output = NULL;
-
- if (VERBOSE)
- fprintf(stderr,">>> Entering state machine\n");
-
- switch(d_state) {
-
- case STATE_SYNC_SEARCH: // Look for flag indicating beginning of pkt
- if (VERBOSE)
- fprintf(stderr,"SYNC Search, noutput=%d\n", noutput_items);
-
- if (sig[0]) { // Found it, set up for header decode
- enter_have_sync();
- }
- break;
-
- case STATE_HAVE_SYNC:
- // only demod after getting the preamble signal; otherwise, the
- // equalizer taps will screw with the PLL performance
- bytes = demapper(&in[0], d_bytes_out);
-
- if (VERBOSE) {
- if(sig[0])
- printf("ERROR -- Found SYNC in HAVE_SYNC\n");
- fprintf(stderr,"Header Search bitcnt=%d, header=0x%08x\n",
- d_headerbytelen_cnt, d_header);
- }
-
- j = 0;
- while(j < bytes) {
- d_header = (d_header << 8) | (d_bytes_out[j] & 0xFF);
- j++;
-
- if (++d_headerbytelen_cnt == HEADERBYTELEN) {
-
- if (VERBOSE)
- fprintf(stderr, "got header: 0x%08x\n", d_header);
-
- // we have a full header, check to see if it has been received properly
- if (header_ok()){
- enter_have_header();
-
- if (VERBOSE)
- printf("\nPacket Length: %d\n", d_packetlen);
-
- while((j < bytes) && (d_packetlen_cnt < d_packetlen)) {
- d_packet[d_packetlen_cnt++] = d_bytes_out[j++];
- }
-
- if(d_packetlen_cnt == d_packetlen) {
- gr_message_sptr msg =
- gr_make_message(0, d_packet_whitener_offset, 0, d_packetlen);
- memcpy(msg->msg(), d_packet, d_packetlen_cnt);
- d_target_queue->insert_tail(msg); // send it
- msg.reset(); // free it up
-
- enter_search();
- }
- }
- else {
- enter_search(); // bad header
- }
- }
- }
- break;
-
- case STATE_HAVE_HEADER:
- bytes = demapper(&in[0], d_bytes_out);
-
- if (VERBOSE) {
- if(sig[0])
- printf("ERROR -- Found SYNC in HAVE_HEADER at %d, length of %d\n", d_packetlen_cnt, d_packetlen);
- fprintf(stderr,"Packet Build\n");
- }
-
- j = 0;
- while(j < bytes) {
- d_packet[d_packetlen_cnt++] = d_bytes_out[j++];
-
- if (d_packetlen_cnt == d_packetlen){ // packet is filled
- // build a message
- // NOTE: passing header field as arg1 is not scalable
- gr_message_sptr msg =
- gr_make_message(0, d_packet_whitener_offset, 0, d_packetlen_cnt);
- memcpy(msg->msg(), d_packet, d_packetlen_cnt);
-
- d_target_queue->insert_tail(msg); // send it
- msg.reset(); // free it up
-
- enter_search();
- break;
- }
- }
- break;
-
- default:
- assert(0);
-
- } // switch
-
- return 1;
-}