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Some tweaks to the V.22bis modem, so it builds OK in a fixed point build

This commit is contained in:
Steve Underwood 2011-12-14 23:18:24 +08:00
parent cc08b939c4
commit 80d5c5aa53
4 changed files with 313 additions and 159 deletions
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47
libs/spandsp/src/spandsp/private/v22bis.h
View File

@ -26,10 +26,10 @@
#if !defined(_SPANDSP_PRIVATE_V22BIS_H_)
#define _SPANDSP_PRIVATE_V22BIS_H_
/*! The number of steps to the left and to the right of the target position in the equalizer buffer. */
#define V22BIS_EQUALIZER_LEN 7
/*! One less than a power of 2 >= (2*V22BIS_EQUALIZER_LEN + 1) */
#define V22BIS_EQUALIZER_MASK 15
/*! The length of the equalizer buffer */
#define V22BIS_EQUALIZER_LEN 17
/*! Samples before the target position in the equalizer buffer */
#define V22BIS_EQUALIZER_PRE_LEN 8
/*! The number of taps in the transmit pulse shaping filter */
#define V22BIS_TX_FILTER_STEPS 9
@ -99,9 +99,9 @@ struct v22bis_state_s
/* Receive section */
struct
{
#if defined(SPANDSP_USE_FIXED_POINTx)
#if defined(SPANDSP_USE_FIXED_POINT)
/*! \brief The scaling factor accessed by the AGC algorithm. */
float agc_scaling;
int16_t agc_scaling;
/*! \brief The root raised cosine (RRC) pulse shaping filter buffer. */
int16_t rrc_filter[V22BIS_RX_FILTER_STEPS];
#else
@ -131,15 +131,14 @@ struct v22bis_state_s
uint32_t carrier_phase;
/*! \brief The update rate for the phase of the carrier (i.e. the DDS increment). */
int32_t carrier_phase_rate;
#if defined(SPANDSP_USE_FIXED_POINTx)
#if defined(SPANDSP_USE_FIXED_POINT)
/*! \brief A measure of how much mismatch there is between the real constellation,
and the decoded symbol positions. */
float training_error;
int32_t training_error;
/*! \brief The proportional part of the carrier tracking filter. */
float carrier_track_p;
int32_t carrier_track_p;
/*! \brief The integral part of the carrier tracking filter. */
float carrier_track_i;
int32_t carrier_track_i;
#else
/*! \brief A measure of how much mismatch there is between the real constellation,
and the decoded symbol positions. */
@ -166,20 +165,20 @@ struct v22bis_state_s
int constellation_state;
#if defined(SPANDSP_USE_FIXED_POINTx)
#if defined(SPANDSP_USE_FIXED_POINT)
/*! \brief The current delta factor for updating the equalizer coefficients. */
float eq_delta;
int16_t eq_delta;
/*! \brief The adaptive equalizer coefficients. */
complexi_t eq_coeff[2*V22BIS_EQUALIZER_LEN + 1];
complexi16_t eq_coeff[V22BIS_EQUALIZER_LEN];
/*! \brief The equalizer signal buffer. */
complexi_t eq_buf[V22BIS_EQUALIZER_MASK + 1];
complexi16_t eq_buf[V22BIS_EQUALIZER_LEN];
#else
/*! \brief The current delta factor for updating the equalizer coefficients. */
float eq_delta;
/*! \brief The adaptive equalizer coefficients. */
complexf_t eq_coeff[2*V22BIS_EQUALIZER_LEN + 1];
complexf_t eq_coeff[V22BIS_EQUALIZER_LEN];
/*! \brief The equalizer signal buffer. */
complexf_t eq_buf[V22BIS_EQUALIZER_MASK + 1];
complexf_t eq_buf[V22BIS_EQUALIZER_LEN];
#endif
/*! \brief Current offset into the equalizer buffer. */
int eq_step;
@ -205,20 +204,22 @@ struct v22bis_state_s
/* Transmit section */
struct
{
#if defined(SPANDSP_USE_FIXED_POINTx)
#if defined(SPANDSP_USE_FIXED_POINT)
/*! \brief The guard tone level. */
float guard_level;
int16_t guard_tone_gain;
/*! \brief The gain factor needed to achieve the specified output power. */
float gain;
int16_t gain;
/*! \brief The root raised cosine (RRC) pulse shaping filter buffer. */
complexf_t rrc_filter[2*V22BIS_TX_FILTER_STEPS];
int16_t rrc_filter_re[V22BIS_TX_FILTER_STEPS];
int16_t rrc_filter_im[V22BIS_TX_FILTER_STEPS];
#else
/*! \brief The guard tone level. */
float guard_level;
float guard_tone_gain;
/*! \brief The gain factor needed to achieve the specified output power. */
float gain;
/*! \brief The root raised cosine (RRC) pulse shaping filter buffer. */
complexf_t rrc_filter[2*V22BIS_TX_FILTER_STEPS];
float rrc_filter_re[V22BIS_TX_FILTER_STEPS];
float rrc_filter_im[V22BIS_TX_FILTER_STEPS];
#endif
/*! \brief Current offset into the RRC pulse shaping filter buffer. */

4
libs/spandsp/src/spandsp/v22bis.h
View File

@ -86,7 +86,11 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx_fillin(v22bis_state_t *s, int len);
\brief Get a snapshot of the current equalizer coefficients.
\param coeffs The vector of complex coefficients.
\return The number of coefficients in the vector. */
#if defined(SPANDSP_USE_FIXED_POINT)
SPAN_DECLARE(int) v22bis_rx_equalizer_state(v22bis_state_t *s, complexi16_t **coeffs);
#else
SPAN_DECLARE(int) v22bis_rx_equalizer_state(v22bis_state_t *s, complexf_t **coeffs);
#endif
/*! Get the current received carrier frequency.
\param s The modem context.

258
libs/spandsp/src/v22bis_rx.c
View File

@ -69,9 +69,9 @@
#include "spandsp/private/logging.h"
#include "spandsp/private/v22bis.h"
#if defined(SPANDSP_USE_FIXED_POINTx)
#include "v22bis_rx_1200_floating_rrc.h"
#include "v22bis_rx_2400_floating_rrc.h"
#if defined(SPANDSP_USE_FIXED_POINT)
#include "v22bis_rx_1200_fixed_rrc.h"
#include "v22bis_rx_2400_fixed_rrc.h"
#else
#include "v22bis_rx_1200_floating_rrc.h"
#include "v22bis_rx_2400_floating_rrc.h"
@ -79,6 +79,11 @@
#define ms_to_symbols(t) (((t)*600)/1000)
#if defined(SPANDSP_USE_FIXED_POINT)
#define FP_FACTOR 4096
#define FP_SHIFT_FACTOR 12
#endif
/*! The adaption rate coefficient for the equalizer */
#define EQUALIZER_DELTA 0.25f
/*! The number of phase shifted coefficient set for the pulse shaping/bandpass filter */
@ -167,24 +172,28 @@ void v22bis_report_status_change(v22bis_state_t *s, int status)
}
/*- End of function --------------------------------------------------------*/
#if defined(SPANDSP_USE_FIXED_POINT)
SPAN_DECLARE(int) v22bis_rx_equalizer_state(v22bis_state_t *s, complexi16_t **coeffs)
#else
SPAN_DECLARE(int) v22bis_rx_equalizer_state(v22bis_state_t *s, complexf_t **coeffs)
#endif
{
*coeffs = s->rx.eq_coeff;
return 2*V22BIS_EQUALIZER_LEN + 1;
return V22BIS_EQUALIZER_LEN;
}
/*- End of function --------------------------------------------------------*/
void v22bis_equalizer_coefficient_reset(v22bis_state_t *s)
{
/* Start with an equalizer based on everything being perfect */
#if defined(SPANDSP_USE_FIXED_POINTx)
cvec_zeroi16(s->rx.eq_coeff, 2*V22BIS_EQUALIZER_LEN + 1);
s->rx.eq_coeff[V22BIS_EQUALIZER_LEN] = complex_seti16(3*FP_FACTOR, 0*FP_FACTOR);
s->rx.eq_delta = 32768.0f*EQUALIZER_DELTA/(2*V22BIS_EQUALIZER_LEN + 1);
#if defined(SPANDSP_USE_FIXED_POINT)
cvec_zeroi16(s->rx.eq_coeff, V22BIS_EQUALIZER_LEN);
s->rx.eq_coeff[V22BIS_EQUALIZER_PRE_LEN] = complex_seti16(FP_Q_4_12(3.0), FP_Q_4_12(0.0));
s->rx.eq_delta = 32768.0f*EQUALIZER_DELTA/V22BIS_EQUALIZER_LEN;
#else
cvec_zerof(s->rx.eq_coeff, 2*V22BIS_EQUALIZER_LEN + 1);
s->rx.eq_coeff[V22BIS_EQUALIZER_LEN] = complex_setf(3.0f, 0.0f);
s->rx.eq_delta = EQUALIZER_DELTA/(2*V22BIS_EQUALIZER_LEN + 1);
cvec_zerof(s->rx.eq_coeff, V22BIS_EQUALIZER_LEN);
s->rx.eq_coeff[V22BIS_EQUALIZER_PRE_LEN] = complex_setf(3.0f, 0.0f);
s->rx.eq_delta = EQUALIZER_DELTA/V22BIS_EQUALIZER_LEN;
#endif
}
/*- End of function --------------------------------------------------------*/
@ -192,63 +201,68 @@ void v22bis_equalizer_coefficient_reset(v22bis_state_t *s)
static void equalizer_reset(v22bis_state_t *s)
{
v22bis_equalizer_coefficient_reset(s);
#if defined(SPANDSP_USE_FIXED_POINTx)
cvec_zeroi16(s->rx.eq_buf, V22BIS_EQUALIZER_MASK + 1);
#if defined(SPANDSP_USE_FIXED_POINT)
cvec_zeroi16(s->rx.eq_buf, V22BIS_EQUALIZER_LEN);
#else
cvec_zerof(s->rx.eq_buf, V22BIS_EQUALIZER_MASK + 1);
cvec_zerof(s->rx.eq_buf, V22BIS_EQUALIZER_LEN);
#endif
s->rx.eq_put_step = 20 - 1;
s->rx.eq_step = 0;
}
/*- End of function --------------------------------------------------------*/
static complexf_t equalizer_get(v22bis_state_t *s)
#if defined(SPANDSP_USE_FIXED_POINT)
static __inline__ complexi16_t equalizer_get(v22bis_state_t *s)
{
int i;
int p;
complexf_t z;
complexf_t z1;
complexi32_t zz;
complexi16_t z;
/* Get the next equalized value. */
z = complex_setf(0.0f, 0.0f);
p = s->rx.eq_step - 1;
for (i = 0; i < 2*V22BIS_EQUALIZER_LEN + 1; i++)
{
p = (p - 1) & V22BIS_EQUALIZER_MASK;
z1 = complex_mulf(&s->rx.eq_coeff[i], &s->rx.eq_buf[p]);
z = complex_addf(&z, &z1);
}
zz = cvec_circular_dot_prodi16(s->rx.eq_buf, s->rx.eq_coeff, V22BIS_EQUALIZER_LEN, s->rx.eq_step);
z.re = zz.re >> FP_SHIFT_FACTOR;
z.im = zz.im >> FP_SHIFT_FACTOR;
return z;
}
#else
static __inline__ complexf_t equalizer_get(v22bis_state_t *s)
{
/* Get the next equalized value. */
return cvec_circular_dot_prodf(s->rx.eq_buf, s->rx.eq_coeff, V22BIS_EQUALIZER_LEN, s->rx.eq_step);
}
#endif
/*- End of function --------------------------------------------------------*/
static void tune_equalizer(v22bis_state_t *s, const complexf_t *z, const complexf_t *target)
#if defined(SPANDSP_USE_FIXED_POINT)
static void tune_equalizer(v22bis_state_t *s, const complexi16_t *z, const complexi16_t *target)
{
int i;
int p;
complexf_t ez;
complexf_t z1;
complexi16_t err;
/* Find the x and y mismatch from the exact constellation position. */
ez = complex_subf(target, z);
ez.re *= s->rx.eq_delta;
ez.im *= s->rx.eq_delta;
p = s->rx.eq_step - 1;
for (i = 0; i < 2*V22BIS_EQUALIZER_LEN + 1; i++)
{
p = (p - 1) & V22BIS_EQUALIZER_MASK;
z1 = complex_conjf(&s->rx.eq_buf[p]);
z1 = complex_mulf(&ez, &z1);
s->rx.eq_coeff[i] = complex_addf(&s->rx.eq_coeff[i], &z1);
/* If we don't leak a little bit we seem to get some wandering adaption */
s->rx.eq_coeff[i].re *= 0.9999f;
s->rx.eq_coeff[i].im *= 0.9999f;
}
err.re = target->re*FP_FACTOR - z->re;
err.im = target->im*FP_FACTOR - z->im;
err.re = ((int32_t) err.re*s->rx.eq_delta) >> 15;
err.im = ((int32_t) err.im*s->rx.eq_delta) >> 15;
cvec_circular_lmsi16(s->rx.eq_buf, s->rx.eq_coeff, V22BIS_EQUALIZER_LEN, s->rx.eq_step, &err);
}
#else
static void tune_equalizer(v22bis_state_t *s, const complexf_t *z, const complexf_t *target)
{
complexf_t err;
/* Find the x and y mismatch from the exact constellation position. */
err = complex_subf(target, z);
err.re *= s->rx.eq_delta;
err.im *= s->rx.eq_delta;
cvec_circular_lmsf(s->rx.eq_buf, s->rx.eq_coeff, V22BIS_EQUALIZER_LEN, s->rx.eq_step, &err);
}
#endif
/*- End of function --------------------------------------------------------*/
#if defined(SPANDSP_USE_FIXED_POINT)
static __inline__ void track_carrier(v22bis_state_t *s, const complexi16_t *z, const complexi16_t *target)
#else
static __inline__ void track_carrier(v22bis_state_t *s, const complexf_t *z, const complexf_t *target)
#endif
{
float error;
@ -336,40 +350,69 @@ static int decode_baudx(v22bis_state_t *s, int nearest)
static __inline__ void symbol_sync(v22bis_state_t *s)
{
#if defined(SPANDSP_USE_FIXED_POINT)
int32_t p;
int32_t q;
complexi16_t zz;
complexi16_t a;
complexi16_t b;
complexi16_t c;
#else
float p;
float q;
complexf_t zz;
complexf_t a;
complexf_t b;
complexf_t c;
#endif
int aa[3];
int i;
int j;
/* This routine adapts the position of the half baud samples entering the equalizer. */
/* Perform a Gardner test for baud alignment on the three most recent samples. */
for (i = 0, j = s->rx.eq_step; i < 3; i++)
{
if (--j < 0)
j = V22BIS_EQUALIZER_LEN - 1;
aa[i] = j;
}
if (s->rx.sixteen_way_decisions)
{
p = s->rx.eq_buf[(s->rx.eq_step - 3) & V22BIS_EQUALIZER_MASK].re
- s->rx.eq_buf[(s->rx.eq_step - 1) & V22BIS_EQUALIZER_MASK].re;
p *= s->rx.eq_buf[(s->rx.eq_step - 2) & V22BIS_EQUALIZER_MASK].re;
p = s->rx.eq_buf[aa[2]].re - s->rx.eq_buf[aa[0]].re;
p *= s->rx.eq_buf[aa[1]].re;
q = s->rx.eq_buf[(s->rx.eq_step - 3) & V22BIS_EQUALIZER_MASK].im
- s->rx.eq_buf[(s->rx.eq_step - 1) & V22BIS_EQUALIZER_MASK].im;
q *= s->rx.eq_buf[(s->rx.eq_step - 2) & V22BIS_EQUALIZER_MASK].im;
q = s->rx.eq_buf[aa[2]].im - s->rx.eq_buf[aa[0]].im;
q *= s->rx.eq_buf[aa[1]].im;
}
else
{
/* Rotate the points to the 45 degree positions, to maximise the effectiveness of
the Gardner algorithm. This is particularly significant at the start of operation
to pull things in quickly. */
zz = complex_setf(0.894427, 0.44721f);
a = complex_mulf(&s->rx.eq_buf[(s->rx.eq_step - 3) & V22BIS_EQUALIZER_MASK], &zz);
b = complex_mulf(&s->rx.eq_buf[(s->rx.eq_step - 2) & V22BIS_EQUALIZER_MASK], &zz);
c = complex_mulf(&s->rx.eq_buf[(s->rx.eq_step - 1) & V22BIS_EQUALIZER_MASK], &zz);
#if defined(SPANDSP_USE_FIXED_POINT)
zz = complex_seti16(FP_Q_6_10(0.894427), FP_Q_6_10(0.44721f));
a = complex_muli16(&s->rx.eq_buf[aa[2]], &zz);
b = complex_muli16(&s->rx.eq_buf[aa[1]], &zz);
c = complex_muli16(&s->rx.eq_buf[aa[0]], &zz);
p = (a.re - c.re)*b.re;
q = (a.im - c.im)*b.im;
#else
zz = complex_setf(0.894427, 0.44721f);
a = complex_mulf(&s->rx.eq_buf[aa[2]], &zz);
b = complex_mulf(&s->rx.eq_buf[aa[1]], &zz);
c = complex_mulf(&s->rx.eq_buf[aa[0]], &zz);
p = (a.re - c.re)*b.re;
q = (a.im - c.im)*b.im;
#endif
}
#if defined(SPANDSP_USE_FIXED_POINT)
s->rx.gardner_integrate += (p + q > 0) ? s->rx.gardner_step : -s->rx.gardner_step;
#else
s->rx.gardner_integrate += (p + q > 0.0f) ? s->rx.gardner_step : -s->rx.gardner_step;
#endif
if (abs(s->rx.gardner_integrate) >= 16)
{
@ -386,11 +429,21 @@ static __inline__ void symbol_sync(v22bis_state_t *s)
}
/*- End of function --------------------------------------------------------*/
#if defined(SPANDSP_USE_FIXED_POINT)
static void process_half_baud(v22bis_state_t *s, const complexi16_t *sample)
#else
static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
#endif
{
#if defined(SPANDSP_USE_FIXED_POINT)
complexi16_t z;
complexi16_t zz;
const complexi16_t *target;
#else
complexf_t z;
complexf_t zz;
const complexf_t *target;
#endif
int re;
int im;
int nearest;
@ -403,7 +456,8 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
/* Add a sample to the equalizer's circular buffer, but don't calculate anything
at this time. */
s->rx.eq_buf[s->rx.eq_step] = z;
s->rx.eq_step = (s->rx.eq_step + 1) & V22BIS_EQUALIZER_MASK;
if (++s->rx.eq_step >= V22BIS_EQUALIZER_LEN)
s->rx.eq_step = 0;
/* On alternate insertions we have a whole baud and must process it. */
if ((s->rx.baud_phase ^= 1))
@ -416,6 +470,18 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
/* Find the constellation point */
if (s->rx.sixteen_way_decisions)
{
#if defined(SPANDSP_USE_FIXED_POINT)
re = (int) (z.re + FP_Q_6_10(3.0f));
if (re > 5)
re = 5;
else if (re < 0)
re = 0;
im = (int) (z.im + FP_Q_6_10(3.0f));
if (im > 5)
im = 5;
else if (im < 0)
im = 0;
#else
re = (int) (z.re + 3.0f);
if (re > 5)
re = 5;
@ -426,13 +492,19 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
im = 5;
else if (im < 0)
im = 0;
#endif
nearest = space_map_v22bis[re][im];
}
else
{
/* Rotate to 45 degrees, to make the slicing trivial */
#if defined(SPANDSP_USE_FIXED_POINT)
zz = complex_seti16(FP_Q_4_12(0.894427), FP_Q_4_12(0.44721f));
zz = complex_muli16(&z, &zz);
#else
zz = complex_setf(0.894427, 0.44721f);
zz = complex_mulf(&z, &zz);
#endif
nearest = 0x01;
if (zz.re < 0.0f)
nearest |= 0x04;
@ -490,10 +562,7 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
error could be higher. */
s->rx.gardner_step = 4;
s->rx.pattern_repeats = 0;
if (s->calling_party)
s->rx.training = V22BIS_RX_TRAINING_STAGE_UNSCRAMBLED_ONES;
else
s->rx.training = V22BIS_RX_TRAINING_STAGE_SCRAMBLED_ONES_AT_1200;
s->rx.training = (s->calling_party) ? V22BIS_RX_TRAINING_STAGE_UNSCRAMBLED_ONES : V22BIS_RX_TRAINING_STAGE_SCRAMBLED_ONES_AT_1200;
/* Be pessimistic and see what the handshake brings */
s->negotiated_bit_rate = 1200;
break;
@ -527,14 +596,14 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
/* It looks like the answering machine is sending us a clean unscrambled 11 or 00 */
if (s->bit_rate == 2400)
{
/* Try to establish at 2400bps */
/* Try to establish at 2400bps. */
span_log(&s->logging, SPAN_LOG_FLOW, "+++ starting U0011 (S1) (Caller)\n");
s->tx.training = V22BIS_TX_TRAINING_STAGE_U0011;
s->tx.training_count = 0;
}
else
{
/* Only try to establish at 1200bps */
/* Only try to establish at 1200bps. */
span_log(&s->logging, SPAN_LOG_FLOW, "+++ starting S11 (1200) (Caller)\n");
s->tx.training = V22BIS_TX_TRAINING_STAGE_S11;
s->tx.training_count = 0;
@ -547,14 +616,14 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
break;
case V22BIS_RX_TRAINING_STAGE_UNSCRAMBLED_ONES_SUSTAINING:
/* Calling modem only */
/* Wait for the end of the unscrambled ones at 1200bps */
/* Wait for the end of the unscrambled ones at 1200bps. */
target = &v22bis_constellation[nearest];
track_carrier(s, &z, target);
raw_bits = phase_steps[((nearest >> 2) - (s->rx.constellation_state >> 2)) & 3];
s->rx.constellation_state = nearest;
if (raw_bits != s->rx.last_raw_bits)
{
/* This looks like the end of the sustained initial unscrambled 11 or 00 */
/* This looks like the end of the sustained initial unscrambled 11 or 00. */
s->tx.training_count = 0;
s->tx.training = V22BIS_TX_TRAINING_STAGE_TIMED_S11;
s->rx.training_count = 0;
@ -600,11 +669,11 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
}
if (s->rx.training_count >= ms_to_symbols(270))
{
/* If we haven't seen the S1 signal by now, we are committed to be in 1200bps mode */
/* If we haven't seen the S1 signal by now, we are committed to be in 1200bps mode. */
if (s->calling_party)
{
span_log(&s->logging, SPAN_LOG_FLOW, "+++ Rx normal operation (1200)\n");
/* The transmit side needs to sustain the scrambled ones for a timed period */
/* The transmit side needs to sustain the scrambled ones for a timed period. */
s->tx.training_count = 0;
s->tx.training = V22BIS_TX_TRAINING_STAGE_TIMED_S11;
/* Normal reception starts immediately */
@ -614,7 +683,7 @@ static void process_half_baud(v22bis_state_t *s, const complexf_t *sample)
else
{
span_log(&s->logging, SPAN_LOG_FLOW, "+++ starting S11 (1200) (Answerer)\n");
/* The transmit side needs to sustain the scrambled ones for a timed period */
/* The transmit side needs to sustain the scrambled ones for a timed period. */
s->tx.training_count = 0;
s->tx.training = V22BIS_TX_TRAINING_STAGE_TIMED_S11;
/* The receive side needs to wait a timed period, receiving scrambled ones,
@ -695,12 +764,21 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx(v22bis_state_t *s, const int16_t amp[], int l
{
int i;
int step;
#if defined(SPANDSP_USE_FIXED_POINT)
complexi16_t z;
complexi16_t zz;
complexi16_t sample;
int32_t ii;
int32_t qq;
float vv;
#else
complexf_t z;
complexf_t zz;
int32_t power;
complexf_t sample;
float ii;
float qq;
#endif
int32_t power;
for (i = 0; i < len; i++)
{
@ -717,7 +795,7 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx(v22bis_state_t *s, const int16_t amp[], int l
if (s->calling_party)
{
#if defined(SPANDSP_USE_FIXED_POINT)
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_2400_re[6], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_2400_re[6], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step) >> 15;
#else
ii = vec_circular_dot_prodf(s->rx.rrc_filter, rx_pulseshaper_2400_re[6], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
#endif
@ -725,7 +803,7 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx(v22bis_state_t *s, const int16_t amp[], int l
else
{
#if defined(SPANDSP_USE_FIXED_POINT)
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_1200_re[6], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_1200_re[6], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step) >> 15;
#else
ii = vec_circular_dot_prodf(s->rx.rrc_filter, rx_pulseshaper_1200_re[6], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
#endif
@ -753,11 +831,25 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx(v22bis_state_t *s, const int16_t amp[], int l
{
/* Only spend effort processing this data if the modem is not
parked, after a training failure. */
#if defined(SPANDSP_USE_FIXED_POINT)
z = dds_complexi16(&s->rx.carrier_phase, s->rx.carrier_phase_rate);
#else
z = dds_complexf(&s->rx.carrier_phase, s->rx.carrier_phase_rate);
#endif
if (s->rx.training == V22BIS_RX_TRAINING_STAGE_SYMBOL_ACQUISITION)
{
/* Only AGC during the initial symbol acquisition, and then lock the gain. */
#if defined(SPANDSP_USE_FIXED_POINT)
vv = 0.18f*3.60f/sqrtf(power);
if (vv > 32767.0f)
s->rx.agc_scaling = 32767;
else if (vv > -32768.0f)
s->rx.agc_scaling = -32768;
else
s->rx.agc_scaling = vv;
#else
s->rx.agc_scaling = 0.18f*3.60f/sqrtf(power);
#endif
}
/* Put things into the equalization buffer at T/2 rate. The Gardner algorithm
will fiddle the step to align this with the symbols. */
@ -774,8 +866,8 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx(v22bis_state_t *s, const int16_t amp[], int l
if (s->calling_party)
{
#if defined(SPANDSP_USE_FIXED_POINT)
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_2400_re[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
qq = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_2400_im[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_2400_re[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step) >> 15;
qq = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_2400_im[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step) >> 15;
#else
ii = vec_circular_dot_prodf(s->rx.rrc_filter, rx_pulseshaper_2400_re[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
qq = vec_circular_dot_prodf(s->rx.rrc_filter, rx_pulseshaper_2400_im[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
@ -784,15 +876,20 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx(v22bis_state_t *s, const int16_t amp[], int l
else
{
#if defined(SPANDSP_USE_FIXED_POINT)
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_1200_re[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
qq = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_1200_im[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
ii = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_1200_re[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step) >> 15;
qq = vec_circular_dot_prodi16(s->rx.rrc_filter, rx_pulseshaper_1200_im[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step) >> 15;
#else
ii = vec_circular_dot_prodf(s->rx.rrc_filter, rx_pulseshaper_1200_re[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
qq = vec_circular_dot_prodf(s->rx.rrc_filter, rx_pulseshaper_1200_im[step], V22BIS_RX_FILTER_STEPS, s->rx.rrc_filter_step);
#endif
}
#if defined(SPANDSP_USE_FIXED_POINT)
sample.re = ((int32_t) ii*s->rx.agc_scaling) >> 10;
sample.im = ((int32_t) qq*s->rx.agc_scaling) >> 10;
#else
sample.re = ii*s->rx.agc_scaling;
sample.im = qq*s->rx.agc_scaling;
#endif
/* Shift to baseband - since this is done in a full complex form, the
result is clean, and requires no further filtering apart from the
equalizer. */
@ -817,7 +914,7 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx_fillin(v22bis_state_t *s, int len)
return 0;
for (i = 0; i < len; i++)
{
#if defined(SPANDSP_USE_FIXED_POINTx)
#if defined(SPANDSP_USE_FIXED_POINT)
dds_advance(&s->rx.carrier_phase, s->rx.carrier_phase_rate);
#else
dds_advancef(&s->rx.carrier_phase, s->rx.carrier_phase_rate);
@ -830,7 +927,7 @@ SPAN_DECLARE_NONSTD(int) v22bis_rx_fillin(v22bis_state_t *s, int len)
int v22bis_rx_restart(v22bis_state_t *s)
{
#if defined(SPANDSP_USE_FIXED_POINTx)
#if defined(SPANDSP_USE_FIXED_POINT)
vec_zeroi16(s->rx.rrc_filter, sizeof(s->rx.rrc_filter)/sizeof(s->rx.rrc_filter[0]));
#else
vec_zerof(s->rx.rrc_filter, sizeof(s->rx.rrc_filter)/sizeof(s->rx.rrc_filter[0]));
@ -861,8 +958,13 @@ int v22bis_rx_restart(v22bis_state_t *s)
s->rx.training_error = 0.0f;
s->rx.total_baud_timing_correction = 0;
/* We want the carrier to pull in faster on the answerer side, as it has very little time to adapt. */
#if defined(SPANDSP_USE_FIXED_POINT)
s->rx.carrier_track_i = (s->calling_party) ? 8000 : 40000;
s->rx.carrier_track_p = 8000000;
#else
s->rx.carrier_track_i = (s->calling_party) ? 8000.0f : 40000.0f;
s->rx.carrier_track_p = 8000000.0f;
#endif
s->negotiated_bit_rate = 1200;

163
libs/spandsp/src/v22bis_tx.c
View File

@ -62,7 +62,7 @@
#include "spandsp/private/logging.h"
#include "spandsp/private/v22bis.h"
#if defined(SPANDSP_USE_FIXED_POINTx)
#if defined(SPANDSP_USE_FIXED_POINT)
#include "v22bis_tx_fixed_rrc.h"
#else
#include "v22bis_tx_floating_rrc.h"
@ -246,24 +246,28 @@ static const int phase_steps[4] =
1, 0, 2, 3
};
#if defined(SPANDSP_USE_FIXED_POINT)
const complexi16_t v22bis_constellation[16] =
#else
const complexf_t v22bis_constellation[16] =
#endif
{
{ 1.0f, 1.0f},
{ 3.0f, 1.0f}, /* 1200bps 00 */
{ 1.0f, 3.0f},
{ 3.0f, 3.0f},
{-1.0f, 1.0f},
{-1.0f, 3.0f}, /* 1200bps 01 */
{-3.0f, 1.0f},
{-3.0f, 3.0f},
{-1.0f, -1.0f},
{-3.0f, -1.0f}, /* 1200bps 10 */
{-1.0f, -3.0f},
{-3.0f, -3.0f},
{ 1.0f, -1.0f},
{ 1.0f, -3.0f}, /* 1200bps 11 */
{ 3.0f, -1.0f},
{ 3.0f, -3.0f}
{ 1, 1},
{ 3, 1}, /* 1200bps 00 */
{ 1, 3},
{ 3, 3},
{-1, 1},
{-1, 3}, /* 1200bps 01 */
{-3, 1},
{-3, 3},
{-1, -1},
{-3, -1}, /* 1200bps 10 */
{-1, -3},
{-3, -3},
{ 1, -1},
{ 1, -3}, /* 1200bps 11 */
{ 3, -1},
{ 3, -3}
};
static int fake_get_bit(void *user_data)
@ -308,9 +312,17 @@ static __inline__ int get_scrambled_bit(v22bis_state_t *s)
}
/*- End of function --------------------------------------------------------*/
#if defined(SPANDSP_USE_FIXED_POINT)
static complexi16_t training_get(v22bis_state_t *s)
#else
static complexf_t training_get(v22bis_state_t *s)
#endif
{
complexf_t z;
#if defined(SPANDSP_USE_FIXED_POINT)
static const complexi16_t zero = {0, 0};
#else
static const complexf_t zero = {0.0f, 0.0f};
#endif
int bits;
/* V.22bis training sequence */
@ -329,20 +341,17 @@ static complexf_t training_get(v22bis_state_t *s)
case V22BIS_TX_TRAINING_STAGE_INITIAL_SILENCE:
/* Silence */
s->tx.constellation_state = 0;
z = complex_setf(0.0f, 0.0f);
break;
return zero;
case V22BIS_TX_TRAINING_STAGE_U11:
/* Send continuous unscrambled ones at 1200bps (i.e. 270 degree phase steps). */
/* Only the answering modem sends unscrambled ones. It is the first thing exchanged between the modems. */
s->tx.constellation_state = (s->tx.constellation_state + phase_steps[3]) & 3;
z = v22bis_constellation[(s->tx.constellation_state << 2) | 0x01];
break;
return v22bis_constellation[(s->tx.constellation_state << 2) | 0x01];
case V22BIS_TX_TRAINING_STAGE_U0011:
/* Continuous unscrambled double dibit 00 11 at 1200bps. This is termed the S1 segment in
the V.22bis spec. It is only sent to request or accept 2400bps mode, and lasts 100+-3ms. After this
timed burst, we unconditionally change to sending scrambled ones at 1200bps. */
s->tx.constellation_state = (s->tx.constellation_state + phase_steps[3*(s->tx.training_count & 1)]) & 3;
z = v22bis_constellation[(s->tx.constellation_state << 2) | 0x01];
if (++s->tx.training_count >= ms_to_symbols(100))
{
span_log(&s->logging, SPAN_LOG_FLOW, "+++ starting S11 after U0011\n");
@ -357,7 +366,7 @@ static complexf_t training_get(v22bis_state_t *s)
s->tx.training = V22BIS_TX_TRAINING_STAGE_TIMED_S11;
}
}
break;
return v22bis_constellation[(s->tx.constellation_state << 2) | 0x01];
case V22BIS_TX_TRAINING_STAGE_TIMED_S11:
/* A timed period of scrambled ones at 1200bps. */
if (++s->tx.training_count >= ms_to_symbols(756))
@ -383,8 +392,7 @@ static complexf_t training_get(v22bis_state_t *s)
bits = scramble(s, 1);
bits = (bits << 1) | scramble(s, 1);
s->tx.constellation_state = (s->tx.constellation_state + phase_steps[bits]) & 3;
z = v22bis_constellation[(s->tx.constellation_state << 2) | 0x01];
break;
return v22bis_constellation[(s->tx.constellation_state << 2) | 0x01];
case V22BIS_TX_TRAINING_STAGE_S1111:
/* Scrambled ones at 2400bps. We send a timed 200ms burst, and switch to normal operation at 2400bps */
bits = scramble(s, 1);
@ -392,7 +400,6 @@ static complexf_t training_get(v22bis_state_t *s)
s->tx.constellation_state = (s->tx.constellation_state + phase_steps[bits]) & 3;
bits = scramble(s, 1);
bits = (bits << 1) | scramble(s, 1);
z = v22bis_constellation[(s->tx.constellation_state << 2) | bits];
if (++s->tx.training_count >= ms_to_symbols(200))
{
/* We have completed training. Now handle some real work. */
@ -402,18 +409,23 @@ static complexf_t training_get(v22bis_state_t *s)
v22bis_report_status_change(s, SIG_STATUS_TRAINING_SUCCEEDED);
s->tx.current_get_bit = s->get_bit;
}
break;
case V22BIS_TX_TRAINING_STAGE_PARKED:
default:
z = complex_setf(0.0f, 0.0f);
break;
return v22bis_constellation[(s->tx.constellation_state << 2) | bits];
}
return z;
return zero;
}
/*- End of function --------------------------------------------------------*/
#if defined(SPANDSP_USE_FIXED_POINT)
static complexi16_t getbaud(v22bis_state_t *s)
#else
static complexf_t getbaud(v22bis_state_t *s)
#endif
{
#if defined(SPANDSP_USE_FIXED_POINT)
static const complexi16_t zero = {0, 0};
#else
static const complexf_t zero = {0.0f, 0.0f};
#endif
int bits;
if (s->tx.training)
@ -428,7 +440,7 @@ static complexf_t getbaud(v22bis_state_t *s)
if (s->tx.shutdown)
{
if (++s->tx.shutdown > 10)
return complex_setf(0.0f, 0.0f);
return zero;
}
/* The first two bits define the quadrant */
bits = get_scrambled_bit(s);
@ -450,11 +462,18 @@ static complexf_t getbaud(v22bis_state_t *s)
SPAN_DECLARE_NONSTD(int) v22bis_tx(v22bis_state_t *s, int16_t amp[], int len)
{
#if defined(SPANDSP_USE_FIXED_POINT)
complexi16_t v;
complexi32_t x;
complexi32_t z;
int16_t iamp;
#else
complexf_t v;
complexf_t x;
complexf_t z;
int i;
int sample;
float famp;
#endif
int sample;
if (s->tx.shutdown > 10)
return 0;
@ -463,28 +482,41 @@ SPAN_DECLARE_NONSTD(int) v22bis_tx(v22bis_state_t *s, int16_t amp[], int len)
if ((s->tx.baud_phase += 3) >= 40)
{
s->tx.baud_phase -= 40;
s->tx.rrc_filter[s->tx.rrc_filter_step] =
s->tx.rrc_filter[s->tx.rrc_filter_step + V22BIS_TX_FILTER_STEPS] = getbaud(s);
v = getbaud(s);
s->tx.rrc_filter_re[s->tx.rrc_filter_step] = v.re;
s->tx.rrc_filter_im[s->tx.rrc_filter_step] = v.im;
if (++s->tx.rrc_filter_step >= V22BIS_TX_FILTER_STEPS)
s->tx.rrc_filter_step = 0;
}
/* Root raised cosine pulse shaping at baseband */
x = complex_setf(0.0f, 0.0f);
for (i = 0; i < V22BIS_TX_FILTER_STEPS; i++)
#if defined(SPANDSP_USE_FIXED_POINT)
x.re = vec_circular_dot_prodi16(s->tx.rrc_filter_re, tx_pulseshaper[TX_PULSESHAPER_COEFF_SETS - 1 - s->tx.baud_phase], V22BIS_TX_FILTER_STEPS, s->tx.rrc_filter_step) >> 4;
x.im = vec_circular_dot_prodi16(s->tx.rrc_filter_im, tx_pulseshaper[TX_PULSESHAPER_COEFF_SETS - 1 - s->tx.baud_phase], V22BIS_TX_FILTER_STEPS, s->tx.rrc_filter_step) >> 4;
/* Now create and modulate the carrier */
z = dds_complexi32(&s->tx.carrier_phase, s->tx.carrier_phase_rate);
iamp = (x.re*z.re - x.im*z.im) >> 15;
iamp = (int16_t) (((int32_t) iamp*s->tx.gain) >> 11);
if (s->tx.guard_phase_rate && (s->tx.rrc_filter_re[s->tx.rrc_filter_step] != 0 || s->tx.rrc_filter_im[s->tx.rrc_filter_step] != 0))
{
x.re += tx_pulseshaper[39 - s->tx.baud_phase][i]*s->tx.rrc_filter[i + s->tx.rrc_filter_step].re;
x.im += tx_pulseshaper[39 - s->tx.baud_phase][i]*s->tx.rrc_filter[i + s->tx.rrc_filter_step].im;
/* Add the guard tone */
iamp += dds_mod(&s->tx.guard_phase, s->tx.guard_phase_rate, s->tx.guard_tone_gain, 0);
}
/* Don't bother saturating. We should never clip. */
amp[sample] = iamp;
#else
/* Root raised cosine pulse shaping at baseband */
x.re = vec_circular_dot_prodf(s->tx.rrc_filter_re, tx_pulseshaper[TX_PULSESHAPER_COEFF_SETS - 1 - s->tx.baud_phase], V22BIS_TX_FILTER_STEPS, s->tx.rrc_filter_step);
x.im = vec_circular_dot_prodf(s->tx.rrc_filter_im, tx_pulseshaper[TX_PULSESHAPER_COEFF_SETS - 1 - s->tx.baud_phase], V22BIS_TX_FILTER_STEPS, s->tx.rrc_filter_step);
/* Now create and modulate the carrier */
z = dds_complexf(&(s->tx.carrier_phase), s->tx.carrier_phase_rate);
famp = (x.re*z.re - x.im*z.im)*s->tx.gain;
if (s->tx.guard_phase_rate && (s->tx.rrc_filter[s->tx.rrc_filter_step].re != 0.0f || s->tx.rrc_filter[s->tx.rrc_filter_step].im != 0.0f))
if (s->tx.guard_phase_rate && (s->tx.rrc_filter_re[s->tx.rrc_filter_step] != 0.0f || s->tx.rrc_filter_im[s->tx.rrc_filter_step] != 0.0f))
{
/* Add the guard tone */
famp += dds_modf(&(s->tx.guard_phase), s->tx.guard_phase_rate, s->tx.guard_level, 0);
famp += dds_modf(&s->tx.guard_phase, s->tx.guard_phase_rate, s->tx.guard_tone_gain, 0);
}
/* Don't bother saturating. We should never clip. */
amp[sample] = (int16_t) lfastrintf(famp);
#endif
}
return sample;
}
@ -492,34 +524,49 @@ SPAN_DECLARE_NONSTD(int) v22bis_tx(v22bis_state_t *s, int16_t amp[], int len)
SPAN_DECLARE(void) v22bis_tx_power(v22bis_state_t *s, float power)
{
float l;
float sig_power;
float guard_tone_power;
float sig_gain;
float guard_tone_gain;
/* If is there is a guard tone we need to scale down the signal power a bit, so the aggregate of the signal
and guard tone power is the specified power. */
if (s->tx.guard_phase_rate == dds_phase_ratef(550.0f))
{
l = 1.6f*powf(10.0f, (power - 1.0f - DBM0_MAX_POWER)/20.0f);
s->tx.gain = l*32768.0f/(TX_PULSESHAPER_GAIN*3.0f);
l = powf(10.0f, (power - 1.0f - 3.0f - DBM0_MAX_POWER)/20.0f);
s->tx.guard_level = l*32768.0f;
sig_power = power - 1.0f;
guard_tone_power = sig_power - 3.0f;
}
else if(s->tx.guard_phase_rate == dds_phase_ratef(1800.0f))
{
l = 1.6f*powf(10.0f, (power - 1.0f - 1.0f - DBM0_MAX_POWER)/20.0f);
s->tx.gain = l*32768.0f/(TX_PULSESHAPER_GAIN*3.0f);
l = powf(10.0f, (power - 1.0f - 6.0f - DBM0_MAX_POWER)/20.0f);
s->tx.guard_level = l*32768.0f;
sig_power = power - 0.55f;
guard_tone_power = sig_power - 6.0f;
}
else
{
l = 1.6f*powf(10.0f, (power - DBM0_MAX_POWER)/20.0f);
s->tx.gain = l*32768.0f/(TX_PULSESHAPER_GAIN*3.0f);
s->tx.guard_level = 0;
sig_power = power;
guard_tone_power = -9999.0f;
}
sig_gain = 0.4490f*powf(10.0f, (sig_power - DBM0_MAX_POWER)/20.0f)*32768.0f/TX_PULSESHAPER_GAIN;
guard_tone_gain = powf(10.0f, (guard_tone_power - DBM0_MAX_POWER)/20.0f)*32768.0f;
#if defined(SPANDSP_USE_FIXED_POINT)
s->tx.gain = (int16_t) sig_gain;
s->tx.guard_tone_gain = (int16_t) guard_tone_gain;
#else
s->tx.gain = sig_gain;
s->tx.guard_tone_gain = guard_tone_gain;
#endif
}
/*- End of function --------------------------------------------------------*/
static int v22bis_tx_restart(v22bis_state_t *s)
{
cvec_zerof(s->tx.rrc_filter, sizeof(s->tx.rrc_filter)/sizeof(s->tx.rrc_filter[0]));
#if defined(SPANDSP_USE_FIXED_POINT)
vec_zeroi16(s->tx.rrc_filter_re, sizeof(s->tx.rrc_filter_re)/sizeof(s->tx.rrc_filter_re[0]));
vec_zeroi16(s->tx.rrc_filter_im, sizeof(s->tx.rrc_filter_im)/sizeof(s->tx.rrc_filter_im[0]));
#else
vec_zerof(s->tx.rrc_filter_re, sizeof(s->tx.rrc_filter_re)/sizeof(s->tx.rrc_filter_re[0]));
vec_zerof(s->tx.rrc_filter_im, sizeof(s->tx.rrc_filter_im)/sizeof(s->tx.rrc_filter_im[0]));
#endif
s->tx.rrc_filter_step = 0;
s->tx.scramble_reg = 0;
s->tx.scrambler_pattern_count = 0;