997f8eda43
B-Netz: Add timer for switching back from calling channel
...
The timer ensures that the paging sequence is sent out by sound card before
switching back to traffic channel
2016-05-29 17:17:49 +02:00
1ceb3026dd
Fixed link problem with alsa lib
...
Thanx to Martin for pointing to this problem.
2016-05-16 18:41:21 +02:00
90dbc0cbd7
C-Netz: Debug fixes
2016-05-15 20:44:07 +02:00
50136d7e8a
NMT: Typo in channel list
2016-05-15 20:43:58 +02:00
e9640c0cd8
C-Netz: Fix TX polarity selection
2016-05-15 20:43:49 +02:00
9ecb87f3e6
Fixing station ID command line parameter
2016-05-15 20:43:38 +02:00
7aa2445b47
Move amplitude (level) debugging to debug.c
2016-05-15 20:37:06 +02:00
adc3270dc0
Acknowledgements
2016-05-13 20:44:47 +02:00
60d9a7b496
C-Netz: Advice about requirement of emphasis done by software
2016-05-13 19:23:43 +02:00
c2cfce2373
wip: docs
2016-05-13 09:37:03 +02:00
46fa72894e
C-Netz: Calibration/fix processing of tone levels on TX and RX side
...
FSK and compander levels are adjusted.
Eliminate offsets between subsequent speech chunks. This is done by
high-pass filter. An offset is not passed to the filter.
Do correct audio processing chain:
time compress -> compressor -> scrambler / pre-emphasis -> TX
RX -> de-scrambler / de-emphasis -> expander -> time expand
2016-05-13 09:37:03 +02:00
5a9c9c7401
C-Netz: Send 5280 Hz test tone on idle speech channel
2016-05-13 09:37:03 +02:00
bbab972b51
NMT: Fixup paging on other channel
2016-05-13 09:37:03 +02:00
69ccdb99b5
NMT: Calibration of tone levels on TX and RX side
2016-05-13 09:37:03 +02:00
27e8b03df5
Fixup typo on jitter code
2016-05-13 09:37:02 +02:00
42eefe90bf
common code: Fixed de-emphasis by adding high pass filter
...
This high-pass filter filters out DC and frequencies below 300 Hz.
Now de-emphases will not cause low frequencies to saturate audio level
range or cause too high levels on low frequencies.
2016-05-13 09:37:02 +02:00
3a54f46b81
C-Netz: Fixup debug output at database
2016-05-13 09:37:02 +02:00
e2a9c2c6a5
Automatic FSK polarity selection on TX side
...
This is done by simulating two cells with different polarities.
On first message from mobile station, the cell with the correct
polarity is used, the other is disabled.
On RX side the polarity is not selected, since FSK decoder detects
polarity for every frame.
2016-05-13 09:37:01 +02:00
021c34a899
Add geo locations of A-Netz and B-Netz towers. (not exact location)
2016-05-08 16:11:13 +02:00
57ba648ac4
C-Netz: Add tiny database to track if phones are online
...
Reject calls, if not online.
Use an interval to check if the phones are still online.
2016-05-08 15:53:00 +02:00
bae12156a2
common code: Add input gain option
2016-05-08 15:49:45 +02:00
ba91ee82a7
Work on documentation
2016-05-08 15:49:39 +02:00
1ce67c14e9
C-netz: Tuning scrambler
2016-05-08 15:49:29 +02:00
7434e21dc2
Multi transceiver support
...
This can be multiple transceivers on multiple sound cards.
Two transceivers can be bundled on one sound device as well, using both channels.
2016-05-08 15:48:13 +02:00
de0ce7ba98
C-Netz: Correct clear cause on clearing by mobile station
2016-05-08 15:47:01 +02:00
8b6b87d8cc
C-Netz: Lowest mobile station power by default
2016-05-08 15:46:51 +02:00
95f44e9840
C-Netz: Fixed typo
2016-05-08 15:46:43 +02:00
11302272ce
C-Netz: Minor fix on clock speed indication
2016-05-08 15:46:34 +02:00
97c9eee322
Fix display of correct program name
2016-05-08 08:11:35 +02:00
97d4e908a2
Fix test binary location in .gitignore
2016-05-08 08:11:26 +02:00
38692e430b
B-Netz: Calibration of tone levels on TX and RX side
2016-05-08 08:11:17 +02:00
11487eefe8
B-Netz: Minor fixes on signals
2016-05-08 08:11:02 +02:00
aae58d5a68
A-Netz: Calibration of tone levels on TX and RX side
2016-05-06 07:05:52 +02:00
b73894ac49
B-Netz / NMT: minor changes at signal detection
2016-05-06 07:05:40 +02:00
47dbf094d9
NMT: Changes in parity check
2016-05-06 07:05:30 +02:00
28e7f1e9d1
common code: Remove DC level before using Goertzel filter
...
A DC level degrades the quality of the filtered result
2016-05-01 15:15:19 +02:00
0c99848120
common code: Make preemphasis 0 dB @ 1000 Hz
2016-05-01 15:14:57 +02:00
16acdbf59d
Implementation of C-Netz (German mobile telephone system)
2016-04-24 15:19:00 +02:00
4b3e3385b5
common code: Fix sample rate conversion
2016-04-24 15:18:59 +02:00
4356c93afa
common: Add pre and de emphasis, if the radio does not support it
...
Connect to the oscillator of the transmitter - good girl!
You need to enable pre emphasis in this case.
Connect to the discriminator of the receiver - good boy!
You need to enable de emphasis in this case.
2016-04-24 15:14:56 +02:00
5062628e52
NMT: Calculate quality of sync sequence and drop in case of bad quality
...
This eliminates chance of findig a sync sequence in noise or speech
2016-04-24 15:14:56 +02:00
c0cd74ac85
NMT: Show levels of received frames
2016-04-24 15:12:21 +02:00
2a092b8cf7
Fixing compander
2016-04-24 15:10:25 +02:00
9de121109d
common code: Sample rate conversion now supports any rate above 8000 Hz
2016-04-17 16:49:39 +02:00
05402283df
common code: Add function request information, if timer is running
2016-04-17 16:49:08 +02:00
21865b6f0f
Add missing RANLIB definition to configure.ac
2016-04-02 18:34:04 +02:00
17a93b501b
NMT: Fix hint and list of traffic area configuration
2016-03-27 17:56:04 +02:00
4d84da31a8
Fixing timer handling
...
Usage of more than one timer caused a lock-up.
2016-03-27 17:56:04 +02:00
1146537d84
common code: Add feature to record received audio and replay it
...
-W <file.wav> writes a wave file of received audio
-R <file.wav> reads a wave file to feed into decoder
This way you can record a phone and later debug without a phone
and radio equipment.
2016-03-27 17:56:04 +02:00
0aa749d27b
WIP: NMT docs
2016-03-26 17:35:20 +01:00
Andreas Eversberg