diff options
| author | Martin Braun <martin.braun@ettus.com> | 2016-04-29 22:14:02 -0700 |
|---|---|---|
| committer | Martin Braun <martin.braun@ettus.com> | 2016-04-29 22:23:19 -0700 |
| commit | 729a30046691496680f5f3602ff355dece8f59e0 (patch) | |
| tree | f439cf8e1ab95e7d461f3a1391172b2d68d79231 /gr-digital/lib/packet_header_ofdm.cc | |
| parent | 2e77960dd3607744981b5df4249883b77d17ac00 (diff) | |
digital: Fixes to packet_header_ofdm
- For unusual carrier allocations, the parser would report the wrong
number of payload OFDM symbols => Fixed.
- Updated QA code to track this use case.
- Minor whitespace/indentation fixes
Diffstat (limited to 'gr-digital/lib/packet_header_ofdm.cc')
| -rw-r--r-- | gr-digital/lib/packet_header_ofdm.cc | 55 |
1 files changed, 27 insertions, 28 deletions
diff --git a/gr-digital/lib/packet_header_ofdm.cc b/gr-digital/lib/packet_header_ofdm.cc index 4893b866e2..7a9558640e 100644 --- a/gr-digital/lib/packet_header_ofdm.cc +++ b/gr-digital/lib/packet_header_ofdm.cc @@ -74,14 +74,9 @@ namespace gr { bits_per_header_sym), d_frame_len_tag_key(pmt::string_to_symbol(frame_len_tag_key)), d_occupied_carriers(occupied_carriers), - d_syms_per_set(0), d_bits_per_payload_sym(bits_per_payload_sym), d_scramble_mask(d_header_len, 0) { - for (unsigned i = 0; i < d_occupied_carriers.size(); i++) { - d_syms_per_set += d_occupied_carriers[i].size(); - } - // Init scrambler mask if (scramble_header) { // These are just random values which already have OK PAPR: @@ -108,36 +103,40 @@ namespace gr { } bool packet_header_ofdm::header_parser( - const unsigned char *in, - std::vector<tag_t> &tags) - { + const unsigned char *in, + std::vector<tag_t> &tags + ) { std::vector<unsigned char> in_descrambled(d_header_len, 0); for (int i = 0; i < d_header_len; i++) { - in_descrambled[i] = in[i] ^ d_scramble_mask[i]; + in_descrambled[i] = in[i] ^ d_scramble_mask[i]; } if (!packet_header_default::header_parser(&in_descrambled[0], tags)) { - return false; + return false; } - int packet_len = 0; // # of bytes in this frame - for (unsigned i = 0; i < tags.size(); i++) { - if (pmt::equal(tags[i].key, d_len_tag_key)) { - // Convert bytes to complex symbols: - packet_len = pmt::to_long(tags[i].value) * 8 / d_bits_per_payload_sym; - if (pmt::to_long(tags[i].value) * 8 % d_bits_per_payload_sym) { - packet_len++; - } - tags[i].value = pmt::from_long(packet_len); - break; - } + int packet_len = 0; // # of complex symbols in this frame + for (size_t i = 0; i < tags.size(); i++) { + if (pmt::equal(tags[i].key, d_len_tag_key)) { + // Convert bytes to complex symbols: + packet_len = pmt::to_long(tags[i].value) * 8 / d_bits_per_payload_sym; + if (pmt::to_long(tags[i].value) * 8 % d_bits_per_payload_sym) { + packet_len++; + } + tags[i].value = pmt::from_long(packet_len); + break; + } } - // frame_len == # of OFDM symbols in this frame - int frame_len = packet_len / d_syms_per_set; - int k = 0; - int i = frame_len * d_syms_per_set; - while (i < packet_len) { - frame_len++; - i += d_occupied_carriers[k].size(); + // To figure out how many payload OFDM symbols there are in this frame, + // we need to go through the carrier allocation and count the number of + // allocated carriers per OFDM symbol. + // frame_len == # of payload OFDM symbols in this frame + int frame_len = 0; + size_t k = 0; // position in the carrier allocation map + int symbols_accounted_for = 0; + while (symbols_accounted_for < packet_len) { + frame_len++; + symbols_accounted_for += d_occupied_carriers[k].size(); + k = (k + 1) % d_occupied_carriers.size(); } tag_t tag; tag.key = d_frame_len_tag_key; |