Return-Path: Received: (qmail 5506 invoked from network); 21 Nov 2001 10:34:59 -0000 Content-Transfer-Encoding: 8bit Received: from unknown (HELO warrior.services.quay.plus.net) (212.159.14.227) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 21 Nov 2001 10:34:59 -0000 X-Priority: 3 X-MSMail-Priority: Normal Received: (qmail 5311 invoked from network); 21 Nov 2001 10:35:11 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior.services.quay.plus.net with SMTP; 21 Nov 2001 10:35:11 -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 166Ucg-0001JJ-00 for rsgb_lf_group-outgoing@blacksheep.org; Wed, 21 Nov 2001 10:28:54 +0000 Received: from k2.pncl.co.uk ([212.35.226.183]) by post.thorcom.com with esmtp (Exim 3.33 #2) id 166Ucf-0001JE-00 for rsgb_lf_group@blacksheep.org; Wed, 21 Nov 2001 10:28:53 +0000 Received: from blanch.pncl.co.uk (52.234.35.212.in-addr.arpa.ip-pool.cix.co.uk [212.35.234.52]) by k2.pncl.co.uk (8.11.3/8.11.3) with ESMTP id fALASB502393 for ; Wed, 21 Nov 2001 10:28:11 GMT Message-ID: <5.0.2.1.2.20011121102520.00a5ddc0@mail.pncl.co.uk> X-Sender: blanch@mail.pncl.co.uk X-Mailer: QUALCOMM Windows Eudora Version 5.0.2 Date: Wed, 21 Nov 2001 10:28:44 +0000 To: rsgb_lf_group@blacksheep.org From: "Walter Blanchard" Subject: Re: LF: Phased rx In-reply-to: References: <5.0.2.1.2.20011120101111.00a2bb80@mail.pncl.co.uk> <5.0.2.1.2.20011120101111.00a2bb80@mail.pncl.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: At 09:40 21/11/01 Wednesday +0000, you wrote: >On Tue, 20 Nov 2001 11:13:53 +0000, you wrote: > > >As for getting "beams", if you add together a lot of antennas on a long > >baseline (tens of kilometres) whether for Tx or Rx you will get what > >superficially look like multiple narrow "beams" with very deep (40-50 dB) > >nulls between them. The longer the baseline or the more antennas you use > >the more "beams" and nulls you will get. In fact, an interferometer. The > >problem is that the "gain" in any one beam is miniscule, perhaps 0.5 > >dB. > >Would the steerable attenuation be more useful for nulling out >interference than >the gain itself? > >Nick Hi Nick, In theory, yes, but there are multiple nulls of varying depth and you probably don't know which direction they're in.. Accurate phase shifting to do it is a problem, also. Much easier to use a loop! Walter G3JKV.