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Defines | |
#define | _SPANDSP_V17RX_H_ |
#define | V17_EQUALIZER_PRE_LEN 8 |
#define | V17_EQUALIZER_POST_LEN 8 |
#define | V17_RX_FILTER_STEPS 27 |
#define | V17_TRELLIS_STORAGE_DEPTH 16 |
#define | V17_TRELLIS_LOOKBACK_DEPTH 16 |
Typedefs | |
typedef struct v17_rx_state_s | v17_rx_state_t |
Functions | |
v17_rx_state_t * | v17_rx_init (v17_rx_state_t *s, int bit_rate, put_bit_func_t put_bit, void *user_data) |
Initialise a V.17 modem receive context. | |
int | v17_rx_restart (v17_rx_state_t *s, int bit_rate, int short_train) |
Reinitialise an existing V.17 modem receive context. | |
int | v17_rx_release (v17_rx_state_t *s) |
Release a V.17 modem receive context. | |
int | v17_rx_free (v17_rx_state_t *s) |
Free a V.17 modem receive context. | |
logging_state_t * | v17_rx_get_logging_state (v17_rx_state_t *s) |
Get the logging context associated with a V.17 modem receive context. | |
void | v17_rx_set_put_bit (v17_rx_state_t *s, put_bit_func_t put_bit, void *user_data) |
Change the put_bit function associated with a V.17 modem receive context. | |
void | v17_rx_set_modem_status_handler (v17_rx_state_t *s, modem_rx_status_func_t handler, void *user_data) |
Change the modem status report function associated with a V.17 modem receive context. | |
int | v17_rx (v17_rx_state_t *s, const int16_t amp[], int len) |
Process a block of received V.17 modem audio samples. | |
int | v17_rx_fillin (v17_rx_state_t *s, int len) |
Fake processing of a missing block of received V.17 modem audio samples. | |
int | v17_rx_equalizer_state (v17_rx_state_t *s, complexf_t **coeffs) |
Get a snapshot of the current equalizer coefficients. | |
float | v17_rx_carrier_frequency (v17_rx_state_t *s) |
float | v17_rx_symbol_timing_correction (v17_rx_state_t *s) |
float | v17_rx_signal_power (v17_rx_state_t *s) |
void | v17_rx_signal_cutoff (v17_rx_state_t *s, float cutoff) |
void | v17_rx_set_qam_report_handler (v17_rx_state_t *s, qam_report_handler_t handler, void *user_data) |
#define V17_EQUALIZER_POST_LEN 8 |
Samples after the target position in the equalizer buffer
#define V17_EQUALIZER_PRE_LEN 8 |
Samples before the target position in the equalizer buffer
#define V17_RX_FILTER_STEPS 27 |
The number of taps in the pulse shaping/bandpass filter
Referenced by v17_rx().
#define V17_TRELLIS_LOOKBACK_DEPTH 16 |
How far we look back into history for trellis decisions
#define V17_TRELLIS_STORAGE_DEPTH 16 |
The depth of the trellis buffer
typedef struct v17_rx_state_s v17_rx_state_t |
V.17 modem receive side descriptor. This defines the working state for a single instance of a V.17 modem receiver.
int v17_rx | ( | v17_rx_state_t * | s, | |
const int16_t | amp[], | |||
int | len | |||
) |
Process a block of received V.17 modem audio samples.
Process a block of received V.17 modem audio samples.
s | The modem context. | |
amp | The audio sample buffer. | |
len | The number of samples in the buffer. |
References dds_advance(), dds_advancef(), dds_lookup_complexf(), complexf_t::im, power_meter_init(), power_meter_update(), complexf_t::re, SIG_STATUS_CARRIER_DOWN, SIG_STATUS_CARRIER_UP, V17_RX_FILTER_STEPS, v17_rx_restart(), vec_circular_dot_prodf(), and vec_circular_dot_prodi16().
float v17_rx_carrier_frequency | ( | v17_rx_state_t * | s | ) |
Get the current received carrier frequency.
s | The modem context. |
References dds_frequencyf().
int v17_rx_equalizer_state | ( | v17_rx_state_t * | s, | |
complexf_t ** | coeffs | |||
) |
Get a snapshot of the current equalizer coefficients.
Get a snapshot of the current equalizer coefficients.
s | The modem context. | |
coeffs | The vector of complex coefficients. |
References V17_EQUALIZER_LEN.
int v17_rx_fillin | ( | v17_rx_state_t * | s, | |
int | len | |||
) |
Fake processing of a missing block of received V.17 modem audio samples.
Fake processing of a missing block of received V.17 modem audio samples. (e.g due to packet loss).
s | The modem context. | |
len | The number of samples to fake. |
References dds_advance(), dds_advancef(), and span_log().
Referenced by fax_rx_fillin(), and t31_rx_fillin().
int v17_rx_free | ( | v17_rx_state_t * | s | ) |
Free a V.17 modem receive context.
Free a V.17 modem receive context.
s | The modem context. |
logging_state_t* v17_rx_get_logging_state | ( | v17_rx_state_t * | s | ) |
Get the logging context associated with a V.17 modem receive context.
Get the logging context associated with a V.17 modem receive context.
s | The modem context. |
v17_rx_state_t* v17_rx_init | ( | v17_rx_state_t * | s, | |
int | bit_rate, | |||
put_bit_func_t | put_bit, | |||
void * | user_data | |||
) |
Initialise a V.17 modem receive context.
Initialise a V.17 modem receive context.
s | The modem context. | |
bit_rate | The bit rate of the modem. Valid values are 7200, 9600, 12000 and 14400. | |
put_bit | The callback routine used to put the received data. | |
user_data | An opaque pointer passed to the put_bit routine. |
References CARRIER_NOMINAL_FREQ, dds_phase_ratef(), v17_rx_restart(), and v17_rx_signal_cutoff().
int v17_rx_release | ( | v17_rx_state_t * | s | ) |
Release a V.17 modem receive context.
Release a V.17 modem receive context.
s | The modem context. |
int v17_rx_restart | ( | v17_rx_state_t * | s, | |
int | bit_rate, | |||
int | short_train | |||
) |
Reinitialise an existing V.17 modem receive context.
Reinitialise an existing V.17 modem receive context.
s | The modem context. | |
bit_rate | The bit rate of the modem. Valid values are 7200, 9600, 12000 and 14400. | |
short_train | TRUE if a short training sequence is expected. |
References CARRIER_NOMINAL_FREQ, dds_frequencyf(), dds_phase_ratef(), power_meter_init(), and span_log().
Referenced by v17_rx(), and v17_rx_init().
void v17_rx_set_modem_status_handler | ( | v17_rx_state_t * | s, | |
modem_rx_status_func_t | handler, | |||
void * | user_data | |||
) |
Change the modem status report function associated with a V.17 modem receive context.
Change the modem status report function associated with a V.17 modem receive context.
s | The modem context. | |
handler | The callback routine used to report modem status changes. | |
user_data | An opaque pointer. |
void v17_rx_set_put_bit | ( | v17_rx_state_t * | s, | |
put_bit_func_t | put_bit, | |||
void * | user_data | |||
) |
Change the put_bit function associated with a V.17 modem receive context.
Change the put_bit function associated with a V.17 modem receive context.
s | The modem context. | |
put_bit | The callback routine used to handle received bits. | |
user_data | An opaque pointer. |
void v17_rx_set_qam_report_handler | ( | v17_rx_state_t * | s, | |
qam_report_handler_t | handler, | |||
void * | user_data | |||
) |
Set a handler routine to process QAM status reports
s | The modem context. | |
handler | The handler routine. | |
user_data | An opaque pointer passed to the handler routine. |
void v17_rx_signal_cutoff | ( | v17_rx_state_t * | s, | |
float | cutoff | |||
) |
Set the power level at which the carrier detection will cut in
s | The modem context. | |
cutoff | The signal cutoff power, in dBm0. |
References power_meter_level_dbm0().
Referenced by v17_rx_init().
float v17_rx_signal_power | ( | v17_rx_state_t * | s | ) |
Get a current received signal power.
s | The modem context. |
References power_meter_current_dbm0().
float v17_rx_symbol_timing_correction | ( | v17_rx_state_t * | s | ) |
Get the current symbol timing correction since startup.
s | The modem context. |