Return-Path: Received: from mtain-dd02.r1000.mx.aol.com (mtain-dd02.r1000.mx.aol.com [172.29.64.142]) by air-db03.mail.aol.com (v129.4) with ESMTP id MAILINDB034-86974c8955fbae; Thu, 09 Sep 2010 17:47:39 -0400 Received: from post.thorcom.com (unknown [195.171.43.25]) by mtain-dd02.r1000.mx.aol.com (Internet Inbound) with ESMTP id 4519E380000A7; Thu, 9 Sep 2010 17:47:38 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OtoLU-0003Py-4S for rs_out_1@blacksheep.org; Thu, 09 Sep 2010 22:07:48 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OtoLJ-0003Ph-QR for rsgb_lf_group@blacksheep.org; Thu, 09 Sep 2010 22:07:37 +0100 Received: from cmsout01.mbox.net ([165.212.64.31]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OtoLJ-0002s3-0F for rsgb_lf_group@blacksheep.org; Thu, 09 Sep 2010 22:07:38 +0100 Received: from cmsout01.mbox.net (cmsout01-lo [127.0.0.1]) by cmsout01.mbox.net (Postfix) with ESMTP id EBB8B2AC65D for ; Thu, 9 Sep 2010 21:07:29 +0000 (GMT) Received: from cmsapps03.cms.usa.net [165.212.11.132] by cmsout01.mbox.net via smtad (C8.MAIN.3.61T) with ESMTP id XID379oiiVHE3700X01; Thu, 09 Sep 2010 21:07:29 -0000 X-USANET-Source: 165.212.11.132 IN dibene@usa.net cmsapps03.cms.usa.net X-USANET-MsgId: XID379oiiVHE3700X01 Received: from [192.168.1.3] [151.47.216.223] by cmsapps03.cms.usa.net (ESMTPA/dibene@usa.net) via mtad (C8.MAIN.3.65C) with ESMTPA id 486oiiVHA3472M39; Thu, 09 Sep 2010 21:07:26 -0000 X-USANET-Auth: 151.47.216.223 AUTH dibene@usa.net [192.168.1.3] Message-ID: <4C894C8C.6010203@usa.net> Date: Thu, 09 Sep 2010 23:07:24 +0200 From: Alberto di Bene User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.9) Gecko/20100825 Thunderbird/3.1.3 ThunderBrowse/3.3.2 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <4C872B44.4030706@telus.net> <1283930050.6221.41.camel@vaio3rd> <4C879ED3.8030402@usa.net> <1283986494.6287.9.camel@vaio3rd> <4C88EED4.4050107@usa.net> <4C890D37.4070608@iup.uni-heidelberg.de> <4C891308.8090002@usa.net> <4C893046.1050907@telia.com> In-Reply-To: <4C893046.1050907@telia.com> X-Enigmail-Version: 1.1.1 Z-USANET-MsgId: XID486oiiVHb3472X39 X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,MIME_HTML_ONLY=0.001,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: Request for modification of Argo Time base Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.9 required=5.0 tests=HTML_30_40,HTML_MESSAGE, MIME_HTML_ONLY autolearn=no version=2.63 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-aol-global-disposition: S X-AOL-REROUTE: YES x-aol-sid: 3039ac1d408e4c8955fa42d5 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) On 9/9/2010 9:06 PM, Johan H. Bodin wrote: 
why not mix the wanted spectrum slice down to DC (I/Q=
) and then decimate the
signal down to a very low FS and compute a no-so-giant complex-input FFT?=
 Is
there any advantage of making a huge FFT when you don't need more bins tha=
n the
number of vertical pixels?
Johan,

=C2=A0 yes, that is a sensible way to do it. I could reuse some= of the code of Winrad for this. Maybe, if I feel fit when doing that,
I could even add a polyphase FFT to increase the frequency resolution. The only downside to this is that I won't be able to release
the updated version of Argo in a few days, as I had planned...
73=C2=A0 Alberto=C2=A0 I2PHD