diff options
| author | drowe67 <[email protected]> | 2024-05-01 17:03:16 +0930 |
|---|---|---|
| committer | David Rowe <[email protected]> | 2024-05-01 17:03:16 +0930 |
| commit | 6aeb1f52d62a0eea28273990c0df47c21e6ef639 (patch) | |
| tree | 674da31cae9d979c5c43c227d349d2601bf9884b /README_data.md | |
| parent | 15f565ea0090831fc5ce40e4d40e31fc6184d167 (diff) | |
| parent | d321ccf46fa12b62a6a229749f2deb9701b8a805 (diff) | |
Merge branch 'dr-freedata-001' into dr-qam16-cportdr-qam16-cport
Diffstat (limited to 'README_data.md')
| -rw-r--r-- | README_data.md | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/README_data.md b/README_data.md index 1656469..b53b5fa 100644 --- a/README_data.md +++ b/README_data.md @@ -146,7 +146,7 @@ These modes use an OFDM modem with powerful LDPC codes and are designed for send | DATAC3 | 500 | 321 | 126 | (2048,1024) | 3.19 | 74/100 at 0dB | Forward link data (low SNR) | | DATAC4 | 250 | 87 | 56 | (1472,448) | 5.17 | 90/100 at -4dB | Forward link data (low SNR) | | DATAC13 | 200 | 64 | 14 | (384,128) | 2.0 | 90/100 at -4dB | Reverse link ACK packets (low SNR) | -| DATAC14 | 250 | 58 | 3 | (112,56) | 0.69 | 90/100 at -4dB | Reverse link ACK packets (low SNR) | +| DATAC14 | 250 | 58 | 3 | (112,56) | 0.69 | 90/100 at -2dB | Reverse link ACK packets (low SNR) | | QAM16C2 | 2100 | 3100 | 1213 | (16200,9720) | 3.2 | 90/100 at 15dB | Forward link data (high SNR) | Notes: @@ -247,7 +247,7 @@ This command line demonstrates the effect: ``` Try adjusting `--clip` and `No` argument of `ch` (noise level) for different modes. Note the SNR estimates returned from `freedv_data_raw_rx` compared to the SNR from the channel simulator `ch`. You will notice clipping also increases the RMS power and reduces the PER for a given channel noise power. CPAPR will also reduce with clipping enabled. -The following plots illustrate the SNR estimates versus actual channel SNR with and without compression (clipping). Not that even with the uncompressed waveform there is a small offset of around 1dB, possibly due to modem implementation loss or noise in the frequency, phase, or timing estimators. +The following plots illustrate the SNR estimates versus actual channel SNR with and without compression (clipping). Note that even with the uncompressed waveform there is a small offset of around 1dB, possibly due to modem implementation loss or noise in the frequency, phase, or timing estimators.   |
