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Rename dbm0 (level) to speech (level) 

In mobile communications we use speech level instead of milliwatts.
The deviation (FM) is always based on speech level, not on 1 milliwatt.
This commit is contained in:
Andreas Eversberg 2019-12-05 08:33:08 +01:00
parent b2c0b64b2d
commit e3197eec42
4 changed files with 23 additions and 22 deletions
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15
libmobile/sender.c
View File

@ -281,15 +281,16 @@ void sender_destroy(sender_t *sender)
jitter_destroy(&sender->dejitter);
}
void sender_set_fm(sender_t *sender, double max_deviation, double max_modulation, double dBm0_deviation, double max_display)
/* set frequency modulation and parameters */
void sender_set_fm(sender_t *sender, double max_deviation, double max_modulation, double speech_deviation, double max_display)
{
sender->max_deviation = max_deviation;
sender->max_modulation = max_modulation;
sender->dBm0_deviation = dBm0_deviation;
sender->speech_deviation = speech_deviation;
sender->max_display = max_display;
PDEBUG_CHAN(DSENDER, DEBUG_DEBUG, "Maxium deviation: %.1f kHz, Maximum modulation: %.1f kHz\n", max_deviation / 1000.0, max_modulation / 1000.0);
PDEBUG_CHAN(DSENDER, DEBUG_DEBUG, "Deviation at dBm0 (audio level): %.1f kHz\n", dBm0_deviation / 1000.0);
PDEBUG_CHAN(DSENDER, DEBUG_DEBUG, "Deviation at speech level: %.1f kHz\n", speech_deviation / 1000.0);
}
static void gain_samples(sample_t *samples, int length, double gain)
@ -361,8 +362,8 @@ cant_recover:
/* do pre emphasis towards radio */
if (inst->pre_emphasis)
pre_emphasis(&inst->estate, samples[i], count);
/* normal level to frequency deviation of dBm0 */
gain_samples(samples[i], count, inst->dBm0_deviation);
/* normal level to frequency deviation of speech level */
gain_samples(samples[i], count, inst->speech_deviation);
/* set paging signal */
paging_signal[i] = inst->paging_signal;
on[i] = inst->paging_on;
@ -417,8 +418,8 @@ cant_recover:
/* loop through all channels */
for (i = 0, inst = sender; inst; i++, inst = inst->slave) {
/* frequency deviation of dBm0 to normal level */
gain_samples(samples[i], count, 1.0 / inst->dBm0_deviation);
/* frequency deviation of speech level to normal level */
gain_samples(samples[i], count, 1.0 / inst->speech_deviation);
/* rx gain */
if (inst->rx_gain != 1.0)
gain_samples(samples[i], count, inst->rx_gain);

4
libmobile/sender.h
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@ -36,7 +36,7 @@ typedef struct sender {
/* fm levels */
double max_deviation; /* max frequency deviation */
double max_modulation; /* max frequency modulated */
double dBm0_deviation; /* deviation of 1000 Hz reference tone at dBm0 */
double speech_deviation; /* deviation of 1000 Hz reference tone at speech level */
double max_display; /* level of displaying wave form */
/* audio */
@ -92,7 +92,7 @@ extern int cant_recover;
int sender_create(sender_t *sender, const char *kanal, double sendefrequenz, double empfangsfrequenz, const char *audiodev, int use_sdr, int samplerate, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_rx_wave, const char *write_tx_wave, const char *read_rx_wave, const char *read_tx_wave, int loopback, enum paging_signal paging_signal);
void sender_destroy(sender_t *sender);
void sender_set_fm(sender_t *sender, double max_deviation, double max_modulation, double dBm0_deviation, double max_display);
void sender_set_fm(sender_t *sender, double max_deviation, double max_modulation, double speech_deviation, double max_display);
int sender_open_audio(int latspl);
int sender_start_audio(void);
void process_sender_audio(sender_t *sender, int *quit, int latspl);

22
libsendevolumenregler/sendevolumenregler.c
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@ -38,22 +38,22 @@
/*
* Init function
*
* abwaerts_dbs = how many dB per second to lower the amplification, if input signal is above dBm0
* aufwaerts_dbs = how many dB per second to raise the amplification, if input signal is below dBm0
* maximum_db = limit of the output level above dBm0
* abwaerts_dbs = how many dB per second to lower the amplification, if input signal is above db0
* aufwaerts_dbs = how many dB per second to raise the amplification, if input signal is below db0
* maximum_db = limit of the output level above db0
* minimum_db = below this input level, the amplification is not raised, so it stays constant.
* dbm0_level = target level to be treated as 0 dB
* db0_level = target level to be treated as 0 dB
*
* Hopefully this is correct
*
*/
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double dbm0_level)
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double db0_level)
{
memset(state, 0, sizeof(*state));
state->peak = 1.0;
state->envelope = 1.0;
state->dbm0_level = dbm0_level;
state->db0_level = db0_level;
state->step_down = pow(db2level(abwaerts_dbs), 1.0 / samplerate);
state->step_up = pow(db2level(aufwaerts_dbs), 1.0 / samplerate);
state->maximum_level = db2level(maximum_db);
@ -72,10 +72,10 @@ void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, dou
*/
void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num)
{
double value, peak, envelope, step_up, step_down, maximum_level, minimum_level, dbm0_level;
double value, peak, envelope, step_up, step_down, maximum_level, minimum_level, db0_level;
int i;
dbm0_level = state->dbm0_level;
db0_level = state->db0_level;
step_up = state->step_up;
step_down = state->step_down;
maximum_level = state->maximum_level;
@ -84,8 +84,8 @@ void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num)
envelope = state->envelope;
for (i = 0; i < num; i++) {
/* normalize sample value to dbm0_level level */
value = *samples / dbm0_level;
/* normalize sample value to db0_level level */
value = *samples / db0_level;
/* 'peak' is the level that raises directly with the value
* level, but falls as specified by step_up. */
@ -106,7 +106,7 @@ void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num)
if (peak / envelope > maximum_level)
envelope = peak / maximum_level;
*samples++ = value / envelope * dbm0_level;
*samples++ = value / envelope * db0_level;
}
state->envelope = envelope;

4
libsendevolumenregler/sendevolumenregler.h
View File

@ -6,9 +6,9 @@ typedef struct sendevolumenregler {
double step_down;
double minimum_level;
double maximum_level;
double dbm0_level;
double db0_level;
} sendevolumenregler_t;
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double dbm0_level);
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double db0_level);
void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num);