Thomas Kolb
91db4e1f75
rx: implement squelch + symsync reset
...
Whenever the squelch opens, the symsync is reset to prevent lock-up in
that module due to noise.
2024-04-08 22:03:09 +02:00
Thomas Kolb
4b46d87edb
Add missing variable declaration
2024-03-31 22:26:34 +02:00
Thomas Kolb
93fd8aebbc
Lock TX to RX frequency for clients
...
Central nodes (“base stations”) do no longer do coarse frequency estimation,
but do only use the preamble + PLL for fine offset tracking.
2024-03-31 22:23:04 +02:00
Thomas Kolb
4f4128fbd3
test: fixed build errors
2024-03-31 18:01:00 +02:00
Thomas Kolb
8441b12fbd
rx: delay frequency estimation until history was fully refreshed
2024-03-30 22:10:13 +01:00
Thomas Kolb
171a4a369c
rx: fix header checksum verification
2024-03-30 22:07:08 +01:00
Thomas Kolb
79d7f74dfc
rx: use different PLL BW for header and data
2024-03-30 22:06:13 +01:00
Thomas Kolb
bbf7bcf2f0
test/freq_est: add channel simulation
2024-03-30 22:05:02 +01:00
Thomas Kolb
66c88bf889
Improvements to debug scripts
2024-03-30 22:04:26 +01:00
Thomas Kolb
d9707ac4a9
test: add test_rx_file
2024-03-30 21:56:00 +01:00
Thomas Kolb
dd5712eada
Add options parsing module
2024-03-30 21:51:27 +01:00
Thomas Kolb
07555edfdf
Add CRC8 to the header
...
This should prevent wrong decodings of modcod and packet length, which may disrupt decoding of directly following packets.
2024-01-07 00:02:26 +01:00
Thomas Kolb
16aa2ce92c
correlator: improved phase estimation
...
The phase is now calculated based on the preamble correlation directly instead
of the method of the frequency estimator.
2024-01-06 23:54:41 +01:00
Thomas Kolb
ef25ca2388
Enable Hamming 8/4 code for the header
2024-01-05 21:29:41 +01:00
Thomas Kolb
84c172abc7
Fixed iterative frequency refinement; count header errors
2024-01-05 21:28:38 +01:00
Thomas Kolb
3a4be428b5
sdr: stop reading packets if the TX buffer is too full
2024-01-05 14:13:11 +01:00
Thomas Kolb
e807f0617b
rx: skip zero-length packets
...
If passed on, these cause a segmentation fault in the channel decoder. As
zero-length packets currently make no real sense in this protocol, they are
ignored now.
2024-01-05 13:49:50 +01:00
Thomas Kolb
a6f12d876b
sdr: fixed RX sample data conversion
2024-01-05 13:48:41 +01:00
Thomas Kolb
be5fa06950
Handle SIGTERM and SIGINT for graceful shutdown
2024-01-03 22:03:19 +01:00
Thomas Kolb
ee63483b8f
sdr: scale sample for HackRF API
2024-01-03 17:41:35 +01:00
Thomas Kolb
ac087634dd
sdr: ensure that all samples were transmitted before TX is stopped
...
This is done by tracking the time that the transmitter must stay on based on
the number of samples to be transmitted and the sampling rate.
2024-01-03 17:32:51 +01:00
Thomas Kolb
8689ed5b27
Use fsleep instead of nanosleep
2024-01-03 17:29:51 +01:00
Thomas Kolb
fb9c26ccd5
make.sh: allow passing parameters to make
2024-01-03 17:29:05 +01:00
Thomas Kolb
5564f1751a
Fixed TX gain setting
2024-01-03 17:04:47 +01:00
Thomas Kolb
c9d53ed96e
Ensure that buffer is full when transmission starts
2024-01-03 00:33:54 +01:00
Thomas Kolb
628659511c
sdr: properly flush the transmit buffers
2024-01-03 00:25:55 +01:00
Thomas Kolb
497498acd2
rx: fix overflow in symbol buffer
2024-01-03 00:01:27 +01:00
Thomas Kolb
ef0fad4335
Improved handling of up- and downsampling
2024-01-02 23:49:55 +01:00
Thomas Kolb
d55e3ab902
sdr: release buffered data; set sampling rate
2024-01-02 23:25:14 +01:00
Thomas Kolb
2b741acd8a
Use libhackrf directly (not tested yet)
2024-01-02 22:49:16 +01:00
Thomas Kolb
7995f5bef0
Print RX stats periodically instead of debug logging
2024-01-02 19:04:19 +01:00
Thomas Kolb
112a8a1215
Improved logging and soapy stream handling
2023-05-20 22:01:26 +02:00
Thomas Kolb
2b078a4147
Settings updated: 2 Msps, 10 ms TX backoff
2023-05-20 21:59:40 +02:00
Thomas Kolb
a6530da0d0
make.sh: set build type to RelWithDebInfo
2023-05-20 21:58:16 +02:00
Thomas Kolb
f5a367464f
Optimized one-shot frequency synchronization
...
- Ramp-up length increased to 128 symbols (here is room for
improvement!)
- Try to detect the frequency once during ramp-up. To do so, every
second symbol is inverted (to remove the +/-1 symbol toggling) and the
phase difference between neigboring resulting symbols is checked. When
it is low enough for all symbols, the frequency is estimated and
corrected. When frequency estimation was done, it is not retried for a
number of incoming symbols in order to allow the timing estimator to
converge again.
- This approach was verified in a simulated loopback test with frequency
offset and AWGN.
2023-05-17 22:28:18 +02:00
Thomas Kolb
b5bae84994
utils: new and improved plotting scripts
2023-05-17 22:27:40 +02:00
Thomas Kolb
a7db93ab9e
Added test for frequency estimator
2023-05-17 22:26:46 +02:00
Thomas Kolb
e42602633e
freq_est: implement L&R-based symbol-independent frequency estimation
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The RX chain uses this to acquire an initial estimate of the carrier frequency. The estimate is adjusted on every incoming symbol until a preamble is found.
2023-05-14 15:53:14 +02:00
Thomas Kolb
3b7628882c
utils: open output file in binary mode
2023-05-12 13:49:20 +02:00
Thomas Kolb
d17b7b3309
RX: added some asserts
2023-05-12 13:48:18 +02:00
Thomas Kolb
afb25a69d8
Use dynamic linking for liquid-dsp again
2023-05-12 13:47:05 +02:00
Thomas Kolb
7d5b67a257
Add layer 1 software loopback test
2023-05-12 13:46:02 +02:00
Thomas Kolb
c8e0516e80
Implement time-based carrier sensing
...
In the following events, the modem cannot switch to transmit mode for the
given time:
- after a preamble has been received, for 500 ms
- after a packet has been successfully decoded, for 1 ms
- after receive mode was initially enabled, for 500 ms
Note that the times are that long to work around the RX/TX switching of
the hackrf and can be hopefully reduced to <10 milliseconds in a later
version.
2022-05-07 21:17:53 +02:00
Thomas Kolb
886a78018f
RX: write correct sample rate to debug file
2022-05-07 20:13:01 +02:00
Thomas Kolb
b2d6c713e1
Briefly start in TX mode to ensure correct RX frequency
...
Obviously SoapyHackRF does not set the correct RX frequency on startup.
This is a crude but effective workaround.
2022-05-07 20:12:03 +02:00
Thomas Kolb
ec99cedaf4
rx: improvements made during on-air testing
...
- limit frequency adjustment range
- pre-filter the baseband signal to remove out-of-band interference
- reset the frequency acquisition periodically (every 30s) if no preamble is found
2022-04-10 21:58:32 +02:00
Thomas Kolb
2d0bf7eeda
sdr: fixed enumeration output
2022-04-08 16:17:17 +02:00
Thomas Kolb
96f10f7fb6
sdr: add gain configuration
2022-04-08 16:17:00 +02:00
Thomas Kolb
715cda83a8
RX: process samples in larger chunks
2022-04-07 21:17:37 +02:00
Thomas Kolb
3e74093fc7
Retry transmitting zeros
2022-04-07 20:58:08 +02:00
Thomas Kolb