From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from vsmx002.dclux.xion.oxcs.net (vsmx002.dclux.xion.oxcs.net [185.74.65.108]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 5AC9D3CB37 for ; Wed, 31 Aug 2022 05:59:19 -0400 (EDT) Received: from proxy-1.proxy.oxio.ns.xion.oxcs.net (proxy-1.proxy.oxio.ns.xion.oxcs.net [83.61.18.4]) by mx-out.dclux.xion.oxcs.net (Postfix) with ESMTPA id 25F268C643F for ; Wed, 31 Aug 2022 09:59:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=dclux.xion.oxcs.net; s=mail1; t=1661939958; bh=eeTpbwsGuToUF+71nE2FhibDlQ4Og7k63nFZja9JQKk=; h=Date:From:To:In-Reply-To:References:Subject:From; b=jJ8QIcYTdwCO+bpLHtMhXECG08gRlo23T0Dd0RuXTxeCb2a/K8f2wB/fvQVQ4xnk8 R4JrcxsoHb3KN53x+cYpKMBCZnap2d2Rv5W+UfeVX++Vc4JesCkvO/zSI1hFyX4Er0 Bb6eCXDuNxINwBpnqZRCJ55g41LyTq5q8/xaLwHd0gOF8alRNlAk8rj4jYwumoDgap YhkZm+7CFQRZWb+bVP8GbrVKA45KKwWRq8ecy2IQk4xksBKL2pLXvfM5CeJiAFsnSQ gNHd3iRXs0PzwJar8+dEvlekcTIgDm0AC4NFcE5P9j6zCPb7WNX23l6Wb7qLbRtO90 68XC3Pui/wxpQ== Date: Wed, 31 Aug 2022 11:59:10 +0200 From: Mike Puchol To: starlink@lists.bufferbloat.net Message-ID: In-Reply-To: <8978587-42op-q175-2o41-qq9p4491459s@ynat.uz> References: <1661878433.14064713@apps.rackspace.com> <6p5n9262-3745-pq31-5636-1rnon987o255@ynat.uz> <20220830220710.GA2653@sunf10.rd.bbc.co.uk> <15982a40-2b34-7ed1-bfa3-bced03fc3839@auckland.ac.nz> <9CE05D69-FC37-4C97-9D8D-D46B2DF6DE16@gmx.de> <2321be3b-957f-2d1f-c335-119c8e76efe5@auckland.ac.nz> <8978587-42op-q175-2o41-qq9p4491459s@ynat.uz> X-Readdle-Message-ID: be8f4d46-f310-4bf4-ade5-2744f301b4ca@Spark MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="630f30f3_2e48f044_2eb" X-VadeSecure-Status: LEGIT X-VADE-STATUS: LEGIT Subject: Re: [Starlink] Starlink "beam spread" X-BeenThere: starlink@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Starlink has bufferbloat. Bad." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 31 Aug 2022 09:59:19 -0000 --630f30f3_2e48f044_2eb Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On this particular one, the gateway beams are extremely narrow, around 1.= 5=C2=BA to 2.5=C2=BA. SpaceX is working on =E2=80=9Cmega-gateways=E2=80=9D= where 32 antennas will co-exist. They are also deploying a new gateway d= esign with a larger antenna, and thus narrower beamwidth and more gain, a= llowing for a considerable reduction in TX power. Best, Mike On Aug 31, 2022, 09:33 +0200, David Lang via Starlink , wrote: > On Wed, 31 Aug 2022, Ulrich Speidel via Starlink wrote: > > > This combines with the uncomfortable truth > > that an R=46 =22beam=22 from a satellite isn't as selective as a lase= r beam, > > so the options for frequency re-use from orbit aren't anywhere near a= s > > good as from a mobile base station across the road: Any beam pointed = at > > you can be heard for many miles around and therefore no other user ca= n > > re-use that frequency (with the same burst slot etc.). > > not quite, you are forgetting that the antennas on the ground are also = steerable > arrays and so they can focus their 'receiving beam' at different satell= ites. > This is less efficient than a transmitting beam as the satellites you a= ren't > 'pointed' at will increase your noise floor, but it does allow the same= > frequency to be used for multiple satellites into the same area at the = same > time. > > David Lang > =5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F= =5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F > Starlink mailing list > Starlink=40lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/starlink --630f30f3_2e48f044_2eb Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
On this particular one, the gateway beams are extre= mely narrow, around 1.5=C2=BA to 2.5=C2=BA. SpaceX is working on =E2=80=9C= mega-gateways=E2=80=9D where 32 antennas will co-exist. They are also dep= loying a new gateway design with a larger antenna, and thus narrower beam= width and more gain, allowing for a considerable reduction in TX power.

Best,

Mike
On Aug 31, 2022, 09:33 +0200, David= Lang via Starlink <starlink=40lists.bufferbloat.net>, wrote:
=
On Wed, 31 Aug 2022, Ulrich Speidel via Starlink wrote:

This combines with the uncomfortable truth<= br /> that an R=46 =22beam=22 from a satellite isn't as selective as a laser be= am,
so the options for frequency re-use from orbit aren't anywhere near as good as from a mobile base station across the road: Any beam pointed at you can be heard for many miles around and therefore no other user can re-use that frequency (with the same burst slot etc.).
=
not quite, you are forgetting that the antennas on the ground are also st= eerable
arrays and so they can focus their 'receiving beam' at different satellit= es.
This is less efficient than a transmitting beam as the satellites you are= n't
'pointed' at will increase your noise floor, but it does allow the same frequency to be used for multiple satellites into the same area at the sa= me
time.

David Lang
=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F= =5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F
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