|To:||[email protected], rsgb_lf_group <[email protected]>|
|Subject:||LF: QRA Codes for LF ?|
|From:||Andy Talbot <[email protected]>|
|Date:||Wed, 10 Aug 2016 15:41:54 +0100|
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There is currently work going on in the WSJT development suite with a new class of error correcting code, Q-ary Repeat Accumulate , or QRA codes. These appear to give several dB of improvement when used with the same modulation format as existing convolutional or Reed Solomon error correction.
A paper by Nico Palermo IV3NWV on QRA coding is being presented at the EME conference, and can be found here:
Is anyone working on any low speed implementation for LF use. Seems to show possibilities.
There's also JT9 within the WSJT-X suite which in its narrowest form has a symbol rate and hence S/N comparable to WSPR2, but with QSO capability
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