Return-Path: Received: (qmail 22525 invoked from network); 8 Jan 2002 09:06:09 -0000 Received: from unknown (HELO warrior.services.quay.plus.net) (212.159.14.227) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 8 Jan 2002 09:06:09 -0000 Content-Transfer-Encoding: 8bit Received: (qmail 21339 invoked from network); 8 Jan 2002 09:06:08 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior.services.quay.plus.net with SMTP; 8 Jan 2002 09:06:08 -0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Received: from majordom by post.thorcom.com with local (Exim 3.33 #2) id 16Ns7D-0006Uw-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 08 Jan 2002 09:00:15 +0000 Received: from bob.dera.gov.uk ([192.5.29.90]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 16Ns7C-0006Ur-00 for rsgb_lf_group@blacksheep.org; Tue, 08 Jan 2002 09:00:14 +0000 Received: by bob.dera.gov.uk; (8.8.8/1.3/10May95) id JAA22585; Tue, 8 Jan 2002 09:09:00 GMT Received: (qmail 27838 invoked from network); 8 Jan 2002 09:48:42 -0000 Received: from gauntlet.mail.dstl.gov.uk (192.168.9.10) by baton.dstl.gov.uk with SMTP; 8 Jan 2002 09:48:42 -0000 Received: by gauntlet.mail.dstl.gov.uk; id JAA25510; Tue, 8 Jan 2002 09:18:50 GMT Received: from unknown(172.17.128.171) by gauntlet.mail.dstl.gov.uk via smap (3.2) id xma025496; Tue, 8 Jan 02 09:18:26 GMT Received: from FRN-MAIL-R3.dstl.gov.uk (unverified) by mailguard.dstl.gov.uk (Content Technologies SMTPRS 4.1.5) with ESMTP id for ; Tue, 8 Jan 2002 09:05:15 +0000 Received: by frn-mail-r3.dstl.gov.uk with Internet Mail Service (5.5.2650.21) id ; Tue, 8 Jan 2002 08:59:03 -0000 Message-ID: <7D653C9C42F5D411A27C00508BF8803DCB993D@pdw-mail-r1.dstl.gov.uk> From: "Talbot Andrew" To: rsgb_lf_group@blacksheep.org Subject: LF: RE: GPS Coherant PSK Transmission Date: Tue, 8 Jan 2002 08:58:54 -0000 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset=iso-8859-1; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Oh yes, forgot to say it was 30 bits long this time :-( Transmitted from 1800z through to 0745z The sequence I sent was 010100010110101001010101011101 Which is not what you received, but : Inverting this sequence gives : 101011101001010110101010100010. Then slipping it by 14 bits (denoted here by the decimal point) and with spaces added every 5 for clarity as you do : 01101 01010 10001 0.1010 11101 00101 Which is spot on ! Considering I "Forgot" to mention the longer sequence, you presumably synchronised to a (now non valid) 7.5 minute interval, getting the wrong phase and sequence starting point. An absolute classic demonstration of the necessity for precise timing and coding information needed for fully coherent transmission ! How did you copy this - spectrum spread at transitions, or by absolute phase indication ? Andy G4JNT -----Original Message----- From: John Sexton [mailto:computernetworks@go.com] Sent: 07 January 2002 19:32 To: rsgb_lf_group@blacksheep.org Subject: LF: GPS Coherant PSK Transmission Hi Andy, Tonight's sequence appears to be 15 x 2 bit symbols: 01101 01010 10001 01010 11101 00101 -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on such information is prohibited and may be unlawful.