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Rename dbm0 (level) to speech (level)

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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 c3da4a77d4
commit c2f14834e5
16 changed files with 105 additions and 104 deletions
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34
src/bnetz/dsp.c
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@@ -37,25 +37,25 @@
*
* At 2000 Hz the deviation shall be 4 kHz, so with emphasis the deviation
* at 1000 Hz would be theoretically 2 kHz. This is factor 0.714 below
* 2.8 kHz deviation we want at dBm0.
* 2.8 kHz deviation we want at speech level.
*/
/* signaling */
#define MAX_DEVIATION 4000.0
#define MAX_MODULATION 3000.0
#define DBM0_DEVIATION 2800.0 /* deviation of dBm0 at 1 kHz */
#define TX_PEAK_FSK (4000.0 / 2000.0 * 1000.0 / DBM0_DEVIATION)
#define TX_PEAK_METER (2000.0 / 2900.0 * 1000.0 / DBM0_DEVIATION) /* FIXME: what is the metering pulse deviation??? we use half of the 4kHz deviation, so we can still use -6dB of the speech level */
#define DAMPEN_METER 0.5 /* use -6dB to dampen speech while sending metering pulse (according to FTZ 1727 Pfl 32 Clause 3.2.6.6.5) */
#define MAX_DISPLAY 1.4 /* something above dBm0 */
#define BIT_RATE 100.0
#define BIT_ADJUST 0.5 /* full adjustment on bit change */
#define F0 2070.0
#define F1 1950.0
#define METERING_HZ 2900 /* metering pulse frequency */
#define TONE_DETECT_CNT 7 /* 70 milliseconds to detect continuous tone */
#define TONE_LOST_CNT 14 /* we use twice of the detect time, so we bridge a loss of "TONE_DETECT_CNT duration" */
#define TONE_STDDEV_TH 0.2 /* threshold of bad quality (standard deviation) to reject tone */
#define MAX_DEVIATION 4000.0
#define MAX_MODULATION 3000.0
#define SPEECH_DEVIATION 2800.0 /* deviation of speech at 1 kHz */
#define TX_PEAK_FSK (4000.0 / 2000.0 * 1000.0 / SPEECH_DEVIATION)
#define TX_PEAK_METER (2000.0 / 2900.0 * 1000.0 / SPEECH_DEVIATION) /* FIXME: what is the metering pulse deviation??? we use half of the 4kHz deviation, so we can still use -6dB of the speech level */
#define DAMPEN_METER 0.5 /* use -6dB to dampen speech while sending metering pulse (according to FTZ 1727 Pfl 32 Clause 3.2.6.6.5) */
#define MAX_DISPLAY 1.4 /* something above speech level */
#define BIT_RATE 100.0
#define BIT_ADJUST 0.5 /* full adjustment on bit change */
#define F0 2070.0
#define F1 1950.0
#define METERING_HZ 2900 /* metering pulse frequency */
#define TONE_DETECT_CNT 7 /* 70 milliseconds to detect continuous tone */
#define TONE_LOST_CNT 14 /* we use twice of the detect time, so we bridge a loss of "TONE_DETECT_CNT duration" */
#define TONE_STDDEV_TH 0.2 /* threshold of bad quality (standard deviation) to reject tone */
/* carrier loss detection */
#define MUTE_TIME 0.1 /* time to mute after loosing signal */
@@ -91,7 +91,7 @@ int dsp_init_sender(bnetz_t *bnetz, double squelch_db)
squelch_init(&bnetz->squelch, bnetz->sender.kanal, squelch_db, MUTE_TIME, LOSS_TIME);
/* set modulation parameters */
sender_set_fm(&bnetz->sender, MAX_DEVIATION, MAX_MODULATION, DBM0_DEVIATION, MAX_DISPLAY);
sender_set_fm(&bnetz->sender, MAX_DEVIATION, MAX_MODULATION, SPEECH_DEVIATION, MAX_DISPLAY);
PDEBUG(DDSP, DEBUG_DEBUG, "Using FSK level of %.3f (%.3f KHz deviation @ 2000 Hz)\n", TX_PEAK_FSK, 4.0);