dds_float.c File Reference

#include <stdio.h>
#include <inttypes.h>
#include "floating_fudge.h"
#include "spandsp/telephony.h"
#include "spandsp/complex.h"
#include "spandsp/dds.h"

Defines
#define	SLENK   11
#define	SINELEN   (1 << SLENK)
Functions
int32_t	dds_phase_ratef (float frequency)
	Find the phase rate equivalent to a frequency, in Hz.
float	dds_frequencyf (int32_t phase_rate)
	Find the frequency, in Hz, equivalent to a phase rate.
float	dds_scaling_dbm0f (float level)
	Find the scaling factor equivalent to a dBm0 value.
float	dds_scaling_dbovf (float level)
	Find the scaling factor equivalent to a dBmov value.
void	dds_advancef (uint32_t *phase_acc, int32_t phase_rate)
	Advance the phase, without returning any new signal sample.
float	ddsf (uint32_t *phase_acc, int32_t phase_rate)
	Generate a floating point tone sample.
float	dds_lookupf (uint32_t phase)
	Lookup the floating point value of a specified phase.
float	dds_modf (uint32_t *phase_acc, int32_t phase_rate, float scale, int32_t phase)
	Generate a floating point tone sample, with modulation.
complexf_t	dds_complexf (uint32_t *phase_acc, int32_t phase_rate)
	Generate a complex floating point tone sample.
complexf_t	dds_lookup_complexf (uint32_t phase)
	Lookup the complex value of a specified phase.
complexf_t	dds_complex_modf (uint32_t *phase_acc, int32_t phase_rate, float scale, int32_t phase)
	Generate a complex floating point tone sample, with modulation.

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Detailed Description

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Function Documentation

void dds_advancef	(	uint32_t *	phase_acc,
		int32_t	phase_rate
	)

Advance the phase, without returning any new signal sample.

Parameters:

	phase_acc	A pointer to a phase accumulator value.
	phase_rate	The phase increment to be applied.

Referenced by v17_rx(), v27ter_rx(), v29_rx(), and v32bis_rx().

complexf_t dds_complex_modf	(	uint32_t *	phase_acc,
		int32_t	phase_rate,
		float	scale,
		int32_t	phase
	)

Generate a complex floating point tone sample, with modulation.

Parameters:

	phase_acc	A pointer to a phase accumulator value.
	phase_rate	The phase increment to be applied.
	scale	The scaling factor.
	phase	The phase offset.

Returns:

The complex signal amplitude, between (-1.0, -1.0) and (1.0, 1.0).

complexf_t dds_complexf	(	uint32_t *	phase_acc,
		int32_t	phase_rate
	)

Generate a complex floating point tone sample.

Parameters:

	phase_acc	A pointer to a phase accumulator value.
	phase_rate	The phase increment to be applied.

Returns:

The complex signal amplitude, between (-1.0, -1.0) and (1.0, 1.0).

Referenced by v17_tx(), v22bis_rx(), v22bis_tx(), v27ter_tx(), and v32bis_tx().

float dds_frequencyf

(

int32_t

phase_rate

)

Find the frequency, in Hz, equivalent to a phase rate.

Parameters:

phase_rate

The phase rate.

Returns:

The equivalent frequency, in Hz.

Referenced by v17_rx_carrier_frequency(), v17_rx_restart(), v22bis_rx_carrier_frequency(), v27ter_rx_carrier_frequency(), v29_rx_carrier_frequency(), and v32bis_restart().

complexf_t dds_lookup_complexf

(

uint32_t

phase_acc

)

Lookup the complex value of a specified phase.

Parameters:

phase

The phase accumulator value to be looked up.

Returns:

The complex signal amplitude, between (-1.0, -1.0) and (1.0, 1.0).

Referenced by v17_rx(), v27ter_rx(), v29_rx(), and v32bis_rx().

float dds_lookupf

(

uint32_t

phase

)

Lookup the floating point value of a specified phase.

Parameters:

phase

The phase accumulator value to be looked up.

Returns:

The signal amplitude, between -1.0 and 1.0.

float dds_modf	(	uint32_t *	phase_acc,
		int32_t	phase_rate,
		float	scale,
		int32_t	phase
	)

Generate a floating point tone sample, with modulation.

Parameters:

	phase_acc	A pointer to a phase accumulator value.
	phase_rate	The phase increment to be applied.
	scale	The scaling factor.
	phase	The phase offset.

Returns:

The signal amplitude, between -1.0 and 1.0.

Referenced by super_tone_tx(), and v22bis_tx().

int32_t dds_phase_ratef

(

float

frequency

)

Find the phase rate equivalent to a frequency, in Hz.

Parameters:

frequency

The frequency, in Hz.

Returns:

The equivalent phase rate.

Referenced by make_tone_gen_descriptor(), v17_rx_init(), v17_rx_restart(), v17_tx_init(), v22bis_init(), v22bis_rx_restart(), v27ter_rx_restart(), v27ter_tx_init(), v29_rx_restart(), v29_tx_init(), v32bis_init(), and v32bis_restart().

float dds_scaling_dbm0f

(

float

level

)

Find the scaling factor equivalent to a dBm0 value.

Parameters:

level

The signal level in dBm0.

Returns:

The equivalent scaling factor.

Referenced by dtmf_tx_set_level(), and make_tone_gen_descriptor().

float dds_scaling_dbovf

(

float

level

)

Find the scaling factor equivalent to a dBmov value.

Parameters:

level

The signal level in dBmov.

Returns:

The equivalent scaling factor.

float ddsf	(	uint32_t *	phase_acc,
		int32_t	phase_rate
	)

Generate a floating point tone sample.

Parameters:

	phase_acc	A pointer to a phase accumulator value.
	phase_rate	The phase increment to be applied.

Returns:

The signal amplitude, between -1.0 and 1.0.