From 0c2e969cfbe85548801eeb20ad8113969604892a Mon Sep 17 00:00:00 2001 From: drowe67 Date: Fri, 14 Jul 2023 10:58:22 +0930 Subject: manually fixed spelling errors from codec2 #406 --- README_data.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'README_data.md') diff --git a/README_data.md b/README_data.md index 5433988..17481f3 100644 --- a/README_data.md +++ b/README_data.md @@ -157,7 +157,7 @@ From the callers point of view, the frame format of each burst is: | Preamble | payload data | CRC | payload data | CRC | ........... | Postamble | | frame 1 -----------| frame 2 -----------| ... frame N | ``` -In the next layer down, each frame is comprised of several OFDM "modem frames", that contain pilot, unique word, and FEC symbols to handle syncronisation and error correction over the challenging HF channel. The preamble and postamble are used to locate the burst and estimate it's frequency offset. Having both a pre and postamble increases the probability of successful detection of the burst in a fading channel. Here are some single frame bursts on a MPP channel at 5dB SNR: +In the next layer down, each frame is comprised of several OFDM "modem frames", that contain pilot, unique word, and FEC symbols to handle synchronisation and error correction over the challenging HF channel. The preamble and postamble are used to locate the burst and estimate it's frequency offset. Having both a pre and postamble increases the probability of successful detection of the burst in a fading channel. Here are some single frame bursts on a MPP channel at 5dB SNR: ![](doc/pre_post_amble_mpp.png) -- cgit v1.2.3