TPC and LDPC are used extensively in satellite two-way stuff, for example, Datum satellite modems.
http://datumsystems.com/m7 On Fri, May 20, 2016 at 7:07 AM, Ken Hohhof <af...@kwisp.com> wrote: > Licensed links use FEC, don’t they? Like when they refer to stuff like > 1024 QAM 3/4, that would be a 3/4 rate code. Or SAF where they give you a > choice of weak or strong coding. > > I think all the cool kids are using turbo codes now? > > > *From:* Chuck McCown <ch...@wbmfg.com> > *Sent:* Thursday, May 19, 2016 10:34 PM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] Trango > > I think the square separated the points from each other equally. > I am surprised none of the RF designs use trellis coded modulation. That > was all the rage back in the dial up modem days. > > *From:* Ken Hohhof <af...@kwisp.com> > *Sent:* Thursday, May 19, 2016 8:46 PM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] Trango > > But the max power is a circle (in I-Q plane) set by either regulations or > power amp. And best noise performance is achieved by maximizing vector > distance between constellation points. So a square should be sub optimum. > > > > *From:* Chuck McCown <ch...@wbmfg.com> > *Sent:* Thursday, May 19, 2016 7:45 PM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] Trango > > According to something I read, square is more noise resistant. > > *From:* Ken Hohhof <af...@kwisp.com> > *Sent:* Thursday, May 19, 2016 6:23 PM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] Trango > > Do all these manufacturers really still use square constellations? I > thought when you were trying to eek out every last dB of performance, you > pruned a larger constellation to get a hexagon or something close to a > circle. > > > *From:* Chuck McCown <ch...@wbmfg.com> > *Sent:* Thursday, May 19, 2016 5:26 PM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] Trango > > 13 bits per symbol.... wow. Doesn’t take much noise to ruin your day. > I wonder what the symbol rate is. > > *From:* Eric Kuhnke <eric.kuh...@gmail.com> > *Sent:* Thursday, May 19, 2016 4:16 PM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] Trango > > Did somebody says more QAMs? > > https://twitter.com/ibelings/status/651162559089774592 > > 8192QAM > > But yeah, it's DOCSIS3.1 stuff, so not RF through the air... > > On Thu, May 19, 2016 at 3:05 PM, Ken Hohhof <af...@kwisp.com> wrote: > >> I think the StrataPro is maybe out now (24 GHz). Probably the only way >> to find out availability of 6/11/18/23 GHz is to call them, then apply some >> Kentucky windage. I think they are using some new chipset from Broadcom >> that goes up to 4096QAM? More QAMs, as George would say. Also supposed to >> be high xmt power without consuming a ton of power, due to xmt >> predistortion, if I remember right from the WISPA show. >> >> >> -----Original Message----- From: Dan Petermann >> Sent: Thursday, May 19, 2016 9:44 AM >> To: af@afmug.com >> Subject: [AFMUG] Trango >> >> Does anyone know when the Trango next gen radios are going to hit the >> market? >> >> Where can I find a spec sheet? >> >> >
