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 |
Dkim-signature: | v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:from:date:message-id:subject:to; bh=kC0qBIUW4Y5UQ1OFs7u+HrSaWWbpOWga5F0aDZ5rLis=; b=ikbh2V7UXXjiIT+uHKPWZDstT0rRQ7zcvtoK3B396Cf0cu3cdn32ACc60gQ53cMbGU e3bci/OZfNFpiF6/580Ip50rw0TQOctgaHOMuN00pljnkWvPzYYfORRx7LjKWgF+PjFk pVjeeRo+xnRn2pBmvin4IO0YJc0wlemikM4nms/+BYAcU1YqRGdCw7/6PSZ83iaKiSyn E7zXcOqozpWns3Ooj6VKClEfVzSGrGej0IG2FcaYY8tCUotDN/+K5a0ayXyON82ix/mb oTcQmb+DlAh1P72k11JWPKmjaocZpwC4ssWMBTrfj+8hbvoZMsJ9fwT9L6vGZvw+O9m4 X8ng== |
Reply-to: | [email protected] |
Sender: | [email protected] |
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 Andy G4JNT |
<Prev in Thread] | Current Thread | [Next in Thread> |
---|---|---|
|
Previous by Date: | Re: LF: 137kHz getting better!, jcraig |
---|---|
Next by Date: | LF: 22:53 136 G3XDV de G3XDV Op32 0 mi +4 dB F:1% in Welwyn with ERP0.4w + inv-L, Graham |
Previous by Thread: | LF: 137kHz getting better!, Mike Dennison |
Next by Thread: | LF: 22:53 136 G3XDV de G3XDV Op32 0 mi +4 dB F:1% in Welwyn with ERP0.4w + inv-L, Graham |
Indexes: | [Date] [Thread] [Top] [All Lists] |