Return-Path: X-Spam-DCC: paranoid 1480; Body=2 Fuz1=2 Fuz2=2 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on lipkowski.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=5.0 tests=BAYES_00,DNS_FROM_AHBL_RHSBL, HTML_MESSAGE,SPF_PASS autolearn=no version=3.1.3 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by paranoid.lipkowski.org (8.13.7/8.13.7) with ESMTP id u7AEkotr006334 for ; Wed, 10 Aug 2016 16:46:50 +0200 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1bXUhj-0000TJ-A3 for rs_out_1@blacksheep.org; Wed, 10 Aug 2016 15:41:59 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1bXUhi-0000TA-Kc for rsgb_lf_group@blacksheep.org; Wed, 10 Aug 2016 15:41:58 +0100 Received: from mail-wm0-x230.google.com ([2a00:1450:400c:c09::230]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1bXUhg-0002Jc-O9 for rsgb_lf_group@blacksheep.org; Wed, 10 Aug 2016 15:41:57 +0100 Received: by mail-wm0-x230.google.com with SMTP id f65so94838988wmi.0 for ; Wed, 10 Aug 2016 07:41:56 -0700 (PDT) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain 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== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=kC0qBIUW4Y5UQ1OFs7u+HrSaWWbpOWga5F0aDZ5rLis=; b=mCfpH2RXtw/AN9GHqn6rOwyHlqIj0w/1AL4DCTTtN3BGH109eNT2rJJCJ5A14tyO/Z dR4/TTk9FNgUsuHqDfmqvgtgGD1wi1PzBM+HR4GEuEdQYqjDSTWGDbssR0edFo8A8D1x VqQaZHXjZBDkKCE4xZPfJs9AMfsb1bYFN8+WXohCY1YdoMm7BWG1QVGJU6IrAHIiWEdF gLEkmTUG3+fi5hrvURHranA8EdPtkyVMWq2brgXwmM6nEZhnpiQbsX9VFTfwdsZ44N6J 3skd2jN6zCYQiKetV7DGe/kv2zsAMCCcRn6N5Cp7n190Ji2zFGm8HKzvEYFSPUxeiro1 SVIw== X-Gm-Message-State: AEkoouvliOcyslzCAuVf4T2/maurjVLGAxI8QKPTf7dhBuOwFB8nVLqmcOOg4U+CgMlToB42z9nJ6DSpmGyzqg== X-Received: by 10.25.144.75 with SMTP id s72mr664951lfd.232.1470840115231; Wed, 10 Aug 2016 07:41:55 -0700 (PDT) MIME-Version: 1.0 Received: by 10.25.141.14 with HTTP; Wed, 10 Aug 2016 07:41:54 -0700 (PDT) From: Andy Talbot Date: Wed, 10 Aug 2016 15:41:54 +0100 Message-ID: To: rsgb_lf_group@blacksheep.org, rsgb_lf_group X-Scan-Signature: a6b6ffaf48fdddf1ed5c25dc4bf03ee1 Subject: LF: QRA Codes for LF ? Content-Type: multipart/alternative; boundary=001a1140207697028d0539b8a66b X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false X-Scanned-By: MIMEDefang 2.56 on 10.1.3.11 Status: O X-Status: X-Keywords: X-UID: 8541 --001a1140207697028d0539b8a66b Content-Type: text/plain; charset=UTF-8 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: http://microtelecom.it/qracodes/QRACodes-Rev10.pdf 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 --001a1140207697028d0539b8a66b Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
There is currently work going on in the WSJT development s= uite with a new class of error correcting code, Q-ary Repeat Accumulate , o= r QRA codes.=C2=A0 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 =C2=A0on QRA coding= is being presented at the EME conference, and can be found here:

<= /div>
Is anyone working on any low speed implementation =C2=A0for LF= use.=C2=A0 Seems to show possibilities.

There'= ;s also JT9 within the WSJT-X suite which in its narrowest form has a symbo= l rate and hence S/N comparable to WSPR2, but with QSO capability

Andy =C2=A0G4JNT
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