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update README for newer version.

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This commit is contained in:
Roman Zeyde
2015-01-16 11:53:47 +02:00
parent 603fc75db4
commit d03205fe02
1 changed files with 50 additions and 34 deletions
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README.md
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@@ -87,14 +87,14 @@ If BITRATE is not set, the MODEM will use 1 kbps settings (single frequency with
Change the sender computer's output audio level, until
all frequencies are received well:
```
1000 Hz: good signal
2000 Hz: good signal
3000 Hz: good signal
4000 Hz: good signal
5000 Hz: good signal
6000 Hz: good signal
7000 Hz: good signal
8000 Hz: good signal
9000 Hz: good signal
10000 Hz: good signal
```
If the signal is "too weak", increase the sender's output audio level.
@@ -109,7 +109,7 @@ background noise or increase the signal (without causing saturation).
- Prepare the sender (generate a random binary data file to be sent):
```
~/sender $ dd if=/dev/urandom of=data.tx bs=16kB count=1 status=none
~/sender $ dd if=/dev/urandom of=data.tx bs=10KB count=1 status=none
~/sender $ sha256sum data.tx
008df57d4f3ed6e7a25d25afd57d04fc73140e8df604685bd34fcab58f5ddc01 data.tx
```
@@ -126,41 +126,57 @@ background noise or increase the signal (without causing saturation).
- A similar log should be emitted by the sender:
```
2014-10-23 09:46:36,116 DEBUG MODEM settings: {'F0': 1000.0, 'Nfreq': 8, 'Fs': 32000.0, 'Npoints': 64, 'Tsym': 0.001} amodem:126
2014-10-23 09:46:36,116 DEBUG Running: ['aplay', '-', '-q', '-f', 'S16_LE', '-c', '1', '-r', '32000'] wave.py:20
2014-10-23 09:46:36,665 INFO Sending 2.150 seconds of training audio send.py:69
2014-10-23 09:46:36,665 INFO Starting modulation: <48.000 kbps, 64-QAM, 8 carriers> send.py:74
2014-10-23 09:46:37,735 DEBUG Sent 6.0 kB send.py:56
2014-10-23 09:46:38,794 DEBUG Sent 12.0 kB send.py:56
2014-10-23 09:46:39,440 INFO Sent 16.384 kB @ 2.754 seconds send.py:79
2015-01-16 11:49:25,181 DEBUG Audio OFDM MODEM: 48.0 kb/s (64-QAM x 8 carriers) Fs=32.0 kHz amodem-cli:174
2015-01-16 11:49:27,028 INFO Sending 2.150 seconds of training audio send.py:63
2015-01-16 11:49:27,029 INFO Starting modulation send.py:68
2015-01-16 11:49:28,016 DEBUG Sent 6.000 kB send.py:50
2015-01-16 11:49:28,776 INFO Sent 10.000 kB @ 1.701 seconds send.py:73
```
- A similar log should be emitted by the receiver:
```
2014-10-23 09:46:36,116 DEBUG MODEM settings: {'F0': 1000.0, 'Nfreq': 8, 'Fs': 32000.0, 'Npoints': 64, 'Tsym': 0.001} amodem:126
2014-10-23 09:46:36,238 DEBUG Running: ['arecord', '-', '-q', '-f', 'S16_LE', '-c', '1', '-r', '32000'] wave.py:20
2014-10-23 09:46:36,408 DEBUG Skipping 0.128 seconds recv.py:275
2014-10-23 09:46:36,409 INFO Waiting for carrier tone: 1.0 kHz recv.py:282
2014-10-23 09:46:37,657 INFO Carrier detected at ~886.0 ms @ 1.0 kHz: coherence=99.996%, amplitude=0.475 recv.py:40
2014-10-23 09:46:37,657 DEBUG Buffered 1000 ms of audio recv.py:64
2014-10-23 09:46:37,660 DEBUG Carrier starts at 9.531 ms recv.py:73
2014-10-23 09:46:38,119 DEBUG Prefix OK recv.py:108
2014-10-23 09:46:38,153 DEBUG Current phase on carrier: -0.497 recv.py:121
2014-10-23 09:46:38,153 DEBUG Frequency error: 0.02 ppm recv.py:123
2014-10-23 09:46:38,682 DEBUG 1.0 kHz: SNR = 34.20 dB recv.py:165
2014-10-23 09:46:38,715 DEBUG 2.0 kHz: SNR = 35.05 dB recv.py:165
2014-10-23 09:46:38,766 DEBUG 3.0 kHz: SNR = 35.52 dB recv.py:165
2014-10-23 09:46:38,803 DEBUG 4.0 kHz: SNR = 35.65 dB recv.py:165
2014-10-23 09:46:38,837 DEBUG 5.0 kHz: SNR = 35.03 dB recv.py:165
2014-10-23 09:46:38,869 DEBUG 6.0 kHz: SNR = 35.05 dB recv.py:165
2014-10-23 09:46:38,907 DEBUG 7.0 kHz: SNR = 34.80 dB recv.py:165
2014-10-23 09:46:38,943 DEBUG 8.0 kHz: SNR = 33.74 dB recv.py:165
2014-10-23 09:46:38,977 INFO Starting demodulation: <48.000 kbps, 64-QAM, 8 carriers> recv.py:197
2014-10-23 09:46:39,619 DEBUG Got 6.0 kB, realtime: 64.18%, drift: +0.02 ppm recv.py:215
2014-10-23 09:46:40,538 DEBUG Got 12.0 kB, realtime: 78.03%, drift: +0.02 ppm recv.py:215
2014-10-23 09:46:41,306 DEBUG EOF frame detected framing.py:60
2014-10-23 09:46:41,306 DEBUG Demodulated 16.520 kB @ 2.329 seconds (84.6% realtime) recv.py:244
2014-10-23 09:46:41,306 INFO Received 16.384 kB @ 2.329 seconds = 7.034 kB/s recv.py:247
2015-01-16 11:49:24,369 DEBUG Audio OFDM MODEM: 48.0 kb/s (64-QAM x 8 carriers) Fs=32.0 kHz amodem-cli:174
2015-01-16 11:49:24,382 DEBUG Skipping 0.100 seconds recv.py:214
2015-01-16 11:49:24,535 INFO Waiting for carrier tone: 3.0 kHz recv.py:221
2015-01-16 11:49:26,741 INFO Carrier detected at ~1761.0 ms @ 3.0 kHz: coherence=99.944%, amplitude=0.499 detect.py:64
2015-01-16 11:49:26,741 DEBUG Buffered 1000 ms of audio detect.py:66
2015-01-16 11:49:26,912 DEBUG Carrier starts at 1761.000 ms detect.py:76
2015-01-16 11:49:26,917 DEBUG Carrier symbols amplitude : 0.499 detect.py:101
2015-01-16 11:49:26,917 DEBUG Current phase on carrier: -0.466 detect.py:112
2015-01-16 11:49:26,917 DEBUG Frequency error: -0.01 ppm detect.py:113
2015-01-16 11:49:26,917 DEBUG Frequency correction: 0.005 ppm recv.py:225
2015-01-16 11:49:26,917 DEBUG Gain correction: 2.004 recv.py:228
2015-01-16 11:49:27,099 DEBUG Prefix OK recv.py:48
2015-01-16 11:49:27,925 DEBUG 3.0 kHz: SNR = 40.58 dB recv.py:92
2015-01-16 11:49:27,925 DEBUG 4.0 kHz: SNR = 41.98 dB recv.py:92
2015-01-16 11:49:27,925 DEBUG 5.0 kHz: SNR = 42.81 dB recv.py:92
2015-01-16 11:49:27,925 DEBUG 6.0 kHz: SNR = 43.71 dB recv.py:92
2015-01-16 11:49:27,926 DEBUG 7.0 kHz: SNR = 43.43 dB recv.py:92
2015-01-16 11:49:27,926 DEBUG 8.0 kHz: SNR = 42.96 dB recv.py:92
2015-01-16 11:49:27,926 DEBUG 9.0 kHz: SNR = 42.66 dB recv.py:92
2015-01-16 11:49:27,926 DEBUG 10.0 kHz: SNR = 42.22 dB recv.py:92
2015-01-16 11:49:27,928 INFO Starting demodulation recv.py:119
2015-01-16 11:49:28,008 DEBUG Got 0.600 kB, realtime: 80.73%, drift: -0.00 ppm recv.py:140
2015-01-16 11:49:28,081 DEBUG Got 1.200 kB, realtime: 76.60%, drift: -0.00 ppm recv.py:140
2015-01-16 11:49:28,153 DEBUG Got 1.800 kB, realtime: 75.17%, drift: -0.00 ppm recv.py:140
2015-01-16 11:49:28,224 DEBUG Got 2.400 kB, realtime: 74.02%, drift: -0.00 ppm recv.py:140
2015-01-16 11:49:28,306 DEBUG Got 3.000 kB, realtime: 75.72%, drift: -0.00 ppm recv.py:140
2015-01-16 11:49:28,382 DEBUG Got 3.600 kB, realtime: 75.71%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,458 DEBUG Got 4.200 kB, realtime: 75.72%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,528 DEBUG Got 4.800 kB, realtime: 75.10%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,609 DEBUG Got 5.400 kB, realtime: 75.76%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,686 DEBUG Got 6.000 kB, realtime: 75.80%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,757 DEBUG Got 6.600 kB, realtime: 75.36%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,828 DEBUG Got 7.200 kB, realtime: 75.03%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,909 DEBUG Got 7.800 kB, realtime: 75.50%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:28,980 DEBUG Got 8.400 kB, realtime: 75.15%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:29,051 DEBUG Got 9.000 kB, realtime: 74.88%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:29,261 DEBUG Got 9.600 kB, realtime: 83.31%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:29,342 DEBUG Got 10.200 kB, realtime: 83.23%, drift: -0.01 ppm recv.py:140
2015-01-16 11:49:29,343 DEBUG EOF frame detected framing.py:57
2015-01-16 11:49:29,343 DEBUG Demodulated 10.205 kB @ 1.415 seconds (83.2% realtime) recv.py:165
2015-01-16 11:49:29,343 INFO Received 10.000 kB @ 1.415 seconds = 7.066 kB/s recv.py:169
```
- After the receiver has finished, verify the received file's hash: