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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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14
src/nmt/dsp.c
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@@ -35,11 +35,11 @@
/* Notes on TX_PEAK_FSK level:
*
* This deviation is -2.2db below the dBm0 deviation.
* This deviation is -2.2db below the speech deviation.
*
* At 1800 Hz the deviation shall be 4.2 kHz, so with emphasis the deviation
* at 1000 Hz would be theoretically 2.333 kHz. This is factor 0.777 below
* 3 kHz deviation we want at dBm0.
* 3 kHz deviation we want at speech.
*/
/* Notes on TX_PEAK_SUPER (supervisory signal) level:
@@ -54,14 +54,14 @@
/* signaling */
#define MAX_DEVIATION 4700.0
#define MAX_MODULATION 4055.0
#define DBM0_DEVIATION 3000.0 /* deviation of dBm0 at 1 kHz */
#define TX_PEAK_FSK (4200.0 / 1800.0 * 1000.0 / DBM0_DEVIATION)
#define TX_PEAK_SUPER (300.0 / 4015.0 * 1000.0 / DBM0_DEVIATION)
#define SPEECH_DEVIATION 3000.0 /* deviation of speech at 1 kHz */
#define TX_PEAK_FSK (4200.0 / 1800.0 * 1000.0 / SPEECH_DEVIATION)
#define TX_PEAK_SUPER (300.0 / 4015.0 * 1000.0 / SPEECH_DEVIATION)
#define BIT_RATE 1200.0
#define BIT_ADJUST 0.1 /* how much do we adjust bit clock on frequency change */
#define F0 1800.0
#define F1 1200.0
#define MAX_DISPLAY 1.4 /* something above dBm0 */
#define MAX_DISPLAY 1.4 /* something above speech level */
#define DIALTONE_HZ 425.0 /* dial tone frequency */
#define TX_PEAK_DIALTONE 1.0 /* dial tone peak FIXME: Not found in the specs! */
#define SUPER_DURATION 0.25 /* duration of supervisory signal measurement */
@@ -114,7 +114,7 @@ int dsp_init_sender(nmt_t *nmt, double deviation_factor)
PDEBUG_CHAN(DDSP, DEBUG_DEBUG, "Init DSP for Transceiver.\n");
/* set modulation parameters */
sender_set_fm(&nmt->sender, MAX_DEVIATION * deviation_factor, MAX_MODULATION * deviation_factor, DBM0_DEVIATION * deviation_factor, MAX_DISPLAY);
sender_set_fm(&nmt->sender, MAX_DEVIATION * deviation_factor, MAX_MODULATION * deviation_factor, SPEECH_DEVIATION * deviation_factor, MAX_DISPLAY);
PDEBUG(DDSP, DEBUG_DEBUG, "Using FSK level of %.3f (%.3f KHz deviation @ 1500 Hz)\n", TX_PEAK_FSK * deviation_factor, 3.5 * deviation_factor);
PDEBUG(DDSP, DEBUG_DEBUG, "Using Supervisory level of %.3f (%.3f KHz deviation @ 4015 Hz)\n", TX_PEAK_SUPER * deviation_factor, 0.3 * deviation_factor);