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Author SHA1 Message Date
Ahmet Inan
ba102a5799 added next_sample() 2021-09-06 12:12:13 +02:00
Ahmet Inan
b7855e2c2c use operation mode zero to signal end of transmission 2021-09-06 08:22:56 +02:00
Ahmet Inan
daa47615d3 do the demodulation online using the first preamble 2021-09-06 00:06:33 +02:00
Ahmet Inan
7b45ee894d use the Theil-Sen estimator on each symbol 2021-09-03 20:52:47 +02:00
Ahmet Inan
8d62a3c90b estimate SFO and CFO via simple linear regression 
and compensate by correcting constellation points
 2021-09-03 20:52:47 +02:00
Ahmet Inan
5c2743f5e7 do not resample 2021-09-03 20:52:47 +02:00
Ahmet Inan
99b6a4e963 use a shortened systematic polar code and CA-SCL decoding 
using SPC(64800, 43072):
mode 6: 8PSK, 2700 Hz BW and about 10 seconds long
mode 7: 8PSK, 2500 Hz BW and about 11 seconds long
mode 8: QPSK, 2500 Hz BW and about 16 seconds long
mode 9: QPSK, 2250 Hz BW and about 18 seconds long

using SPC(64512, 43072):
mode 10: 8PSK, 3200 Hz BW and about 9 seconds long
mode 11: 8PSK, 2400 Hz BW and about 11 seconds long
mode 12: QPSK, 2400 Hz BW and about 16 seconds long
mode 13: QPSK, 1600 Hz BW and about 24 seconds long
 2021-09-03 20:52:09 +02:00
Ahmet Inan
a3a56bc830 freq offset needs to be divisible by 50. 
use disorders/cfo if you need finer control
 2021-09-03 20:50:33 +02:00
Ahmet Inan
3665d495b7 added demod_or_erase() helper function 2021-08-29 17:47:20 +02:00
Ahmet Inan
d1adc5c5ca erase constellation points outside of radius two 2021-08-28 18:00:19 +02:00
Ahmet Inan
1d02d34e8c Revert "increased guard interval to 1/4" 
This reverts commit 7c7ed0ffd7.
 2021-08-25 11:41:02 +02:00
Ahmet Inan
5270c7d38f increase power of S&C symbol by two 2021-08-20 21:12:58 +02:00
Ahmet Inan
c81f3a15f9 skip PAPR reduction on S&C symbol 2021-08-20 21:09:00 +02:00
Ahmet Inan
7c7ed0ffd7 increased guard interval to 1/4 
to reduce ISI and support sample rates 11025 Hz and 22050 Hz
 2021-07-27 13:14:00 +02:00
Ahmet Inan
8d5d7fc0c2 use the DVB recommended T=10 BCH code 2021-07-21 17:15:47 +02:00
Ahmet Inan
6f99db1444 improve CFO estimation using hard decision 2021-07-21 00:12:59 +02:00
Ahmet Inan
357a90805c use a simpler estimation for finer CFO 2021-07-20 21:47:49 +02:00
Ahmet Inan
ef152cc53f scramble user data only using Xorshift32 2021-07-18 04:48:32 +02:00
Ahmet Inan
2645f96056 added support for various operation modes: 
mode 2: 8PSK, 2700 Hz bandwidth and about 10 seconds long
mode 3: 8PSK, 2500 Hz bandwidth and about 11 seconds long
mode 4: QPSK, 2500 Hz bandwidth and about 16 seconds long
mode 5: QPSK, 2250 Hz bandwidth and about 18 seconds long
 2021-06-16 19:54:55 +02:00
Ahmet Inan
fa1cc128be use BPSK for the pilot blocks 2021-06-16 19:53:28 +02:00
Ahmet Inan
463836c41f made number of active carriers a constructor argument 2021-06-16 15:16:01 +02:00
Ahmet Inan
07682ac19f added cross-compilation and testing for ARMv7 with NEON 2021-06-15 07:55:08 +02:00
Ahmet Inan
62b07d2d4c make the gcc compiler happy 2021-06-15 07:51:28 +02:00
Ahmet Inan
40ec9a5604 do the clipping in 4x oversampled time domain 2021-06-14 21:43:45 +02:00
Ahmet Inan
42144b8e8a limit introduced noise to active carriers only 2021-06-14 15:52:53 +02:00
Ahmet Inan
39ec8e81a5 improve PAPR by hard clipping the magnitude 2021-06-14 14:00:40 +02:00
Ahmet Inan
82c279f13b minor cleanup 2021-06-13 14:45:44 +02:00
Ahmet Inan
5a6e5cd995 removed payload CRC check: let user decide 2021-06-13 14:35:51 +02:00
Ahmet Inan
c87bfc6e78 added nrz() helper function 2021-06-13 14:19:46 +02:00
Ahmet Inan
5f4c2cdba9 compute descrambled constellations only once 2021-06-13 11:50:55 +02:00
Ahmet Inan
4683e531fe handle erasures produced by LDPC decoding 2021-06-12 13:27:08 +02:00
Ahmet Inan
a1c0ab3d25 interleave bits for improved LDPC performance 2021-06-12 12:15:34 +02:00
Ahmet Inan
a07fe52134 scramble I and Q using two independent sequences 2021-06-11 22:52:01 +02:00
Ahmet Inan
30f39ce41b estimate SNR using corrected symbols 2021-06-11 11:12:52 +02:00
Ahmet Inan
7e362ae224 estimate SNR using hard decision 2021-06-11 11:12:52 +02:00
Ahmet Inan
7ba95fb000 added LDPC forward error correction 2021-06-11 11:12:52 +02:00
Ahmet Inan
1e0b2199af use C++17 for aligned new 2021-06-11 11:12:52 +02:00
Ahmet Inan
0e9f46efd1 added BCH forward error correction 2021-06-11 11:12:52 +02:00
Ahmet Inan
79c0aaf998 minor cleanup 2021-06-11 11:12:52 +02:00
Ahmet Inan
cc3e9cc10f added CRC check of payload 2021-06-11 11:12:52 +02:00
Ahmet Inan
361779211c use bitman.hh 2021-06-11 11:12:52 +02:00
Ahmet Inan
aa28a2e58d pass user data using uint8_t array 2021-06-11 11:12:52 +02:00
Ahmet Inan
3546d516b1 Initial commit 2021-06-11 11:12:44 +02:00