From e3456512afae1af7338e51fd2977748898cf6409 Mon Sep 17 00:00:00 2001 From: drowe67 Date: Wed, 18 Apr 2018 04:25:50 +0000 Subject: [PATCH] added ofdm_demod example git-svn-id: https://svn.code.sf.net/p/freetel/code@3498 01035d8c-6547-0410-b346-abe4f91aad63 --- codec2-dev/README_ofdm.txt | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/codec2-dev/README_ofdm.txt b/codec2-dev/README_ofdm.txt index 531fa43b..3f90b6d5 100644 --- a/codec2-dev/README_ofdm.txt +++ b/codec2-dev/README_ofdm.txt @@ -6,10 +6,9 @@ Created Mar 2018 Introduction ------------ -A 1600 bit/s (nominal uncoded payload data rate) Orthogonal Frequency -Division Multiplexed (OFDM) modem. Used for digital voice over HF -SSB. Designed to be used with a rate 0.5 LDPC code with 700 bit/s -coded voice. +A 1400 bit/s (uncoded data rate) Orthogonal Frequency Division +Multiplexed (OFDM) modem. Used for digital voice over HF SSB. +Designed to be used with a rate 0.5 LDPC code with 700 bit/s voice. The OFDM modem was first implemented in GNU Octave, then ported to C. Algorithm development is generally easier in Octave, but for real time @@ -72,9 +71,13 @@ Built as part of codec2-dev, see README for build instructions. code this is equivalent to 0dB on 1400 bit/s uncoded bits (0dB Eb/No argument for ofdm_tx()) - octave:6> ofdm_ldpc_tx('awgn_ebno_3dB_700d.raw',4,60,3) - octave:7> ofdm_ldpc_rx('awgn_ebno_3dB_700d.raw',4) - + octave:6> ofdm_ldpc_tx('ofdm_test.raw',4,60,3) + octave:7> ofdm_ldpc_rx('ofdm_test.raw',4) + + C demodulator/LDCP decoder: + + build_linux/src$ ./ofdm_demod ../../octave/ofdm_test.raw /dev/null -v -t --ldpc --interleave 4 + Acceptance Tests ---------------- -- 2.25.1