Mercurial > hg > audiostuff
diff spandsp-0.0.6pre17/src/spandsp/private/v29rx.h @ 4:26cd8f1ef0b1
import spandsp-0.0.6pre17
author | Peter Meerwald <pmeerw@cosy.sbg.ac.at> |
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date | Fri, 25 Jun 2010 15:50:58 +0200 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/spandsp-0.0.6pre17/src/spandsp/private/v29rx.h Fri Jun 25 15:50:58 2010 +0200 @@ -0,0 +1,201 @@ +/* + * SpanDSP - a series of DSP components for telephony + * + * private/v29rx.h - ITU V.29 modem receive part + * + * Written by Steve Underwood <steveu@coppice.org> + * + * Copyright (C) 2003 Steve Underwood + * + * 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 Lesser 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, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * $Id: v29rx.h,v 1.2 2009/07/09 13:52:09 steveu Exp $ + */ + +#if !defined(_SPANDSP_PRIVATE_V29RX_H_) +#define _SPANDSP_PRIVATE_V29RX_H_ + +/* Target length for the equalizer is about 63 taps, to deal with the worst stuff + in V.56bis. */ +/*! Samples before the target position in the equalizer buffer */ +#define V29_EQUALIZER_PRE_LEN 16 +/*! Samples after the target position in the equalizer buffer */ +#define V29_EQUALIZER_POST_LEN 14 + +/*! The number of taps in the pulse shaping/bandpass filter */ +#define V29_RX_FILTER_STEPS 27 + +/*! + V.29 modem receive side descriptor. This defines the working state for a + single instance of a V.29 modem receiver. +*/ +struct v29_rx_state_s +{ + /*! \brief The bit rate of the modem. Valid values are 4800, 7200 and 9600. */ + int bit_rate; + /*! \brief The callback function used to put each bit received. */ + put_bit_func_t put_bit; + /*! \brief A user specified opaque pointer passed to the put_bit routine. */ + void *put_bit_user_data; + + /*! \brief The callback function used to report modem status changes. */ + modem_rx_status_func_t status_handler; + /*! \brief A user specified opaque pointer passed to the status function. */ + void *status_user_data; + + /*! \brief A callback function which may be enabled to report every symbol's + constellation position. */ + qam_report_handler_t qam_report; + /*! \brief A user specified opaque pointer passed to the qam_report callback + routine. */ + void *qam_user_data; + + /*! \brief The route raised cosine (RRC) pulse shaping filter buffer. */ +#if defined(SPANDSP_USE_FIXED_POINT) + int16_t rrc_filter[V29_RX_FILTER_STEPS]; +#else + float rrc_filter[V29_RX_FILTER_STEPS]; +#endif + /*! \brief Current offset into the RRC pulse shaping filter buffer. */ + int rrc_filter_step; + + /*! \brief The register for the data scrambler. */ + unsigned int scramble_reg; + /*! \brief The register for the training scrambler. */ + uint8_t training_scramble_reg; + /*! \brief The current step in the table of CD constellation positions. */ + int training_cd; + /*! \brief TRUE if the previous trained values are to be reused. */ + int old_train; + /*! \brief The section of the training data we are currently in. */ + int training_stage; + /*! \brief A count of how far through the current training step we are. */ + int training_count; + /*! \brief A measure of how much mismatch there is between the real constellation, + and the decoded symbol positions. */ + float training_error; + /*! \brief The value of the last signal sample, using the a simple HPF for signal power estimation. */ + int16_t last_sample; + /*! \brief >0 if a signal above the minimum is present. It may or may not be a V.29 signal. */ + int signal_present; + /*! \brief Whether or not a carrier drop was detected and the signal delivery is pending. */ + int carrier_drop_pending; + /*! \brief A count of the current consecutive samples below the carrier off threshold. */ + int low_samples; + /*! \brief A highest magnitude sample seen. */ + int16_t high_sample; + + /*! \brief The position of the current symbol in the constellation, used for + differential decoding. */ + int constellation_state; + + /*! \brief The current phase of the carrier (i.e. the DDS parameter). */ + uint32_t carrier_phase; + /*! \brief The update rate for the phase of the carrier (i.e. the DDS increment). */ + int32_t carrier_phase_rate; + /*! \brief The carrier update rate saved for reuse when using short training. */ + int32_t carrier_phase_rate_save; +#if defined(SPANDSP_USE_FIXED_POINT) + /*! \brief The proportional part of the carrier tracking filter. */ + int32_t carrier_track_p; + /*! \brief The integral part of the carrier tracking filter. */ + int32_t carrier_track_i; +#else + /*! \brief The proportional part of the carrier tracking filter. */ + float carrier_track_p; + /*! \brief The integral part of the carrier tracking filter. */ + float carrier_track_i; +#endif + + /*! \brief A power meter, to measure the HPF'ed signal power in the channel. */ + power_meter_t power; + /*! \brief The power meter level at which carrier on is declared. */ + int32_t carrier_on_power; + /*! \brief The power meter level at which carrier off is declared. */ + int32_t carrier_off_power; + + /*! \brief Current read offset into the equalizer buffer. */ + int eq_step; + /*! \brief Current write offset into the equalizer buffer. */ + int eq_put_step; + /*! \brief Symbol counter to the next equalizer update. */ + int eq_skip; + + /*! \brief The current half of the baud. */ + int baud_half; + +#if defined(SPANDSP_USE_FIXED_POINT) + /*! \brief The scaling factor accessed by the AGC algorithm. */ + int16_t agc_scaling; + /*! \brief The previous value of agc_scaling, needed to reuse old training. */ + int16_t agc_scaling_save; + + /*! \brief The current delta factor for updating the equalizer coefficients. */ + int16_t eq_delta; + /*! \brief The adaptive equalizer coefficients. */ + complexi16_t eq_coeff[V29_EQUALIZER_PRE_LEN + 1 + V29_EQUALIZER_POST_LEN]; + /*! \brief A saved set of adaptive equalizer coefficients for use after restarts. */ + complexi16_t eq_coeff_save[V29_EQUALIZER_PRE_LEN + 1 + V29_EQUALIZER_POST_LEN]; + /*! \brief The equalizer signal buffer. */ + complexi16_t eq_buf[V29_EQUALIZER_PRE_LEN + 1 + V29_EQUALIZER_POST_LEN]; + + /*! Low band edge filter for symbol sync. */ + int32_t symbol_sync_low[2]; + /*! High band edge filter for symbol sync. */ + int32_t symbol_sync_high[2]; + /*! DC filter for symbol sync. */ + int32_t symbol_sync_dc_filter[2]; + /*! Baud phase for symbol sync. */ + int32_t baud_phase; +#else + /*! \brief The scaling factor accessed by the AGC algorithm. */ + float agc_scaling; + /*! \brief The previous value of agc_scaling, needed to reuse old training. */ + float agc_scaling_save; + + /*! \brief The current delta factor for updating the equalizer coefficients. */ + float eq_delta; + /*! \brief The adaptive equalizer coefficients. */ + complexf_t eq_coeff[V29_EQUALIZER_PRE_LEN + 1 + V29_EQUALIZER_POST_LEN]; + /*! \brief A saved set of adaptive equalizer coefficients for use after restarts. */ + complexf_t eq_coeff_save[V29_EQUALIZER_PRE_LEN + 1 + V29_EQUALIZER_POST_LEN]; + /*! \brief The equalizer signal buffer. */ + complexf_t eq_buf[V29_EQUALIZER_PRE_LEN + 1 + V29_EQUALIZER_POST_LEN]; + + /*! Low band edge filter for symbol sync. */ + float symbol_sync_low[2]; + /*! High band edge filter for symbol sync. */ + float symbol_sync_high[2]; + /*! DC filter for symbol sync. */ + float symbol_sync_dc_filter[2]; + /*! Baud phase for symbol sync. */ + float baud_phase; +#endif + + /*! \brief The total symbol timing correction since the carrier came up. + This is only for performance analysis purposes. */ + int total_baud_timing_correction; + + /*! \brief Starting phase angles for the coarse carrier aquisition step. */ + int32_t start_angles[2]; + /*! \brief History list of phase angles for the coarse carrier aquisition step. */ + int32_t angles[16]; + /*! \brief Error and flow logging control */ + logging_state_t logging; +}; + +#endif +/*- End of file ------------------------------------------------------------*/