shallow zip-file copy from codec2 e9d726bf20

1 files changed, 124 insertions, 0 deletions

diff --git a/src/cohpsk_internal.h b/src/cohpsk_internal.h
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+++ b/src/cohpsk_internal.h
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+/*---------------------------------------------------------------------------*\
+
+  FILE........: cohpsk_internal.h
+  AUTHOR......: David Rowe
+  DATE CREATED: March 2015
+
+  Functions that implement a coherent PSK FDM modem.
+
+\*---------------------------------------------------------------------------*/
+
+/*
+  Copyright (C) 2015 David Rowe
+
+  All rights reserved.
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License version 2.1, as
+  published by the Free Software Foundation.  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 Lesser General Public License
+  along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __COHPSK_INTERNAL__
+#define __COHPSK_INTERNAL__
+
+#define NCT_SYMB_BUF      (2*NSYMROWPILOT+2)
+#define COHPSK_ND         2                           /* diversity factor ND 1 is no diveristy, ND we have original plus
+                                                         one copy */
+#define NSW               4                           /* number of sync window frames */
+#define COHPSK_M          100                         /* oversampling rate */
+#define COHPSK_NSYM       6
+#define COHPSK_NFILTER    (COHPSK_NSYM*COHPSK_M)
+#define COHPSK_EXCESS_BW  0.5                         /* excess BW factor of root nyq filter */
+#define COHPSK_NT         5                           /* number of symbols we estimate timing over */
+
+#include "fdmdv_internal.h"
+#include "kiss_fft.h"
+
+struct COHPSK {
+    COMP         ch_fdm_frame_buf[NSW*NSYMROWPILOT*COHPSK_M];  /* buffer of several frames of symbols from channel      */
+    float        pilot2[2*NPILOTSFRAME][COHPSK_NC];
+    float        phi_[NSYMROWPILOT][COHPSK_NC*COHPSK_ND];      /* phase estimates for this frame of rx data symbols     */
+    float        amp_[NSYMROW][COHPSK_NC*COHPSK_ND];           /* amplitude estimates for this frame of rx data symbols */
+    COMP         rx_symb[NSYMROWPILOT][COHPSK_NC*COHPSK_ND];   /* demodulated symbols                                   */
+    float        f_est;
+    COMP         rx_filter_memory[COHPSK_NC*COHPSK_ND][COHPSK_NFILTER];
+    COMP         ct_symb_buf[NCT_SYMB_BUF][COHPSK_NC*COHPSK_ND];
+    int          ct;                                    /* coarse timing offset in symbols                       */
+    float        rx_timing;                             /* fine timing for last symbol in frame                  */
+    int          nin;                                   /* number of samples to input for next symbol            */
+    float        f_fine_est;
+    COMP         ff_rect;
+    COMP         ff_phase;
+    COMP         ct_symb_ff_buf[NSYMROWPILOT+2][COHPSK_NC*COHPSK_ND];
+    int          sync;
+    int          sync_timer;
+
+    int          frame;
+    float        ratio;
+
+    float        sig_rms;
+    float        noise_rms;
+
+    struct FDMDV *fdmdv;
+
+    int           verbose;
+
+    int          *ptest_bits_coh_tx;
+    int          *ptest_bits_coh_rx[2];
+    int          *ptest_bits_coh_end;
+
+    /* counting bit errors using pilots */
+
+    int           npilotbits;
+    int           npilotbiterrors;
+
+    /* optional log variables used for testing Octave to C port */
+
+    COMP          *rx_baseband_log;
+    int            rx_baseband_log_col_index;
+    int            rx_baseband_log_col_sz;
+
+    COMP          *rx_filt_log;
+    int            rx_filt_log_col_index;
+    int            rx_filt_log_col_sz;
+
+    COMP          *ch_symb_log;
+    int            ch_symb_log_r;
+    int            ch_symb_log_col_sz;
+
+    float         *rx_timing_log;
+    int            rx_timing_log_index;
+
+    /* demodulated bits before diversity combination for test/instrumentation purposes */
+
+    float          rx_bits_lower[COHPSK_BITS_PER_FRAME];
+    float          rx_bits_upper[COHPSK_BITS_PER_FRAME];
+
+    /* tx amplitude weights for each carrier for test/instrumentation */
+
+    float          carrier_ampl[COHPSK_NC*COHPSK_ND];
+
+    /* Flag enabling simple freq est mode */
+    int            freq_est_mode_reduced;
+};
+
+void bits_to_qpsk_symbols(COMP tx_symb[][COHPSK_NC*COHPSK_ND], int tx_bits[], int nbits);
+void qpsk_symbols_to_bits(struct COHPSK *coh, float rx_bits[], COMP ct_symb_buf[][COHPSK_NC*COHPSK_ND]);
+void tx_filter_and_upconvert_coh(COMP tx_fdm[], int Nc, const COMP tx_symbols[],
+                                 COMP tx_filter_memory[][COHPSK_NSYM],
+                                 COMP phase_tx[], COMP freq[],
+                                 COMP *fbb_phase, COMP fbb_rect);
+void fdm_downconvert_coh(COMP rx_baseband[][COHPSK_M+COHPSK_M/P], int Nc, COMP rx_fdm[], COMP phase_rx[], COMP freq[], int nin);
+void frame_sync_fine_freq_est(struct COHPSK *coh, COMP ch_symb[][COHPSK_NC*COHPSK_ND], int sync, int *next_sync);
+void fine_freq_correct(struct COHPSK *coh, int sync, int next_sync);
+int sync_state_machine(struct COHPSK *coh, int sync, int next_sync);
+int cohpsk_fs_offset(COMP out[], COMP in[], int n, float sample_rate_ppm);
+
+#endif