Modulations above 256QAM have diminishing returns, especially if you can’t do a true 80 MHz channel. Going from 2048 to 4096 QAM sounds like a huge leap, but it’s really 12 bits instead of 11.
Also important to look at performance during rain fade, like what is xmt power at 256QAM, also how seamlessly does automatic modulation and xmt power work. A radio that excels on those parameters might be as good as one that has a stellar spec at full modulation but then you find that running at 4096 or even 2048 QAM in the real world never quite seems to happen. Also with very high xmt power there’s the question if you’ll be able to coordinate the path at that power level, it will increase the likelihood that you’ll interfere with something existing. From: AF <af-boun...@af.afmug.com> On Behalf Of Peter Kranz Sent: Tuesday, February 26, 2019 4:58 PM To: 'AnimalFarm Microwave Users Group' <af@af.afmug.com> Subject: Re: [AFMUG] Higher power 18Ghz radios.. @Tim.. WTM platform may not support 80Mhz channel in 18Ghz, you may be stuck with 50 Mhz according to the technical datasheet: So, reviewing… The delta between 64Mhz and 80Mhz is not that high.. ~118 Mbps or around 9% which is interesting given the 25% more theoretical BW. Aviat 50 Mhz/2048QAM = 850 Mbps Aviat 80Mhz/2048QAM = 1370 Mbps DW 64 Mhz/2048 QAM = 1252 Mbps Peter Kranz <http://www.unwiredltd.com/> www.UnwiredLtd.com Desk: 510-868-1614 x100 Mobile: 510-207-0000 <mailto:pkr...@unwiredltd.com> pkr...@unwiredltd.com From: AF <af-boun...@af.afmug.com <mailto:af-boun...@af.afmug.com> > On Behalf Of Tim Hardy Sent: Tuesday, February 26, 2019 11:53 AM To: AnimalFarm Microwave Users Group <af@af.afmug.com <mailto:af@af.afmug.com> > Subject: Re: [AFMUG] Higher power 18Ghz radios.. Just an FYI.. According to this chart, the occupied bandwidth is only 64.5 MHz so you will be losing capacity vs radios that occupy the full 80 MHz bandwidth. The DW radio will have to be coordinated and licensed in one of the 80 MHz channel allocations as there are no FCC channel plans between 51 MHz and 79 MHz. There are only 4-channel pairs available at 80 MHz and its difficult to coordinate multiple pairs in many areas as a result. Finally, while these power levels are impressive, they don't tell the full story and you really need to compare the system gain values at the desired modulations. The DW 64.5 MHz radio’s system gain at 2048 QAM is 83 dB vs. the WTM 4100 80 MHz radio’s system gain at 2048 QAM which will be 73.5 dB. On Feb 26, 2019, at 12:19 PM, Peter Kranz <pkr...@unwiredltd.com <mailto:pkr...@unwiredltd.com> > wrote: +31 is the advertised 2048QAM output on the HP variant. Dragonwave contacted me offline and is indicating a March availability. Here is the table of power output levels for that radio. It should also support 4096QAM, but I’m not sure if that’s available in the software yet. <image001.png> Peter Kranz <http://www.unwiredltd.com/> www.UnwiredLtd.com Desk: 510-868-1614 x100 Mobile: 510-207-0000 <mailto:pkr...@unwiredltd.com> pkr...@unwiredltd.com From: AF < <mailto:af-boun...@af.afmug.com> af-boun...@af.afmug.com> On Behalf Of Ken Hohhof Sent: Monday, February 25, 2019 8:27 PM To: 'AnimalFarm Microwave Users Group' < <mailto:af@af.afmug.com> af@af.afmug.com> Subject: Re: [AFMUG] Higher power 18Ghz radios.. Looks like PTP820c is only +16. You’re talking about xmt power actually at 2048QAM modulation, right? +31 is hard to believe. I remember hearing that Broadcom was supposed to have a chip with adaptive digital predistortion for high xmt power also 4096QAM not sure if that became real. From: AF < <mailto:af-boun...@af.afmug.com> af-boun...@af.afmug.com> On Behalf Of Peter Kranz Sent: Monday, February 25, 2019 6:51 PM To: <mailto:af@af.afmug.com> af@af.afmug.com Subject: [AFMUG] Higher power 18Ghz radios.. Dragonwave announced over a year ago the Harmony Enhanced 18HP, with +31 TX power at 2048 QAM, but have never made it to production as far as I know. From the top of my head, here are some of the major radios TX power in 18 Ghz band: Dragonwave Harmony Enahcend HP – 31 <Vaporware?> Dragonwave Harmony Enhanced SP – 22 Bridgewave Navigator – 19 Aviat WTM 4200 – 17.5 SIAE AlfoPlus2 – 17 Curious if anyone is aware of an 18Ghz dual core radio capable of higher TX power at 2048QAM? It’s quite difficult to license 6Ghz or 11Ghz paths in my market. Peter Kranz <http://www.unwiredltd.com/> www.UnwiredLtd.com Desk: 510-868-1614 x100 Mobile: 510-207-0000 <mailto:pkr...@unwiredltd.com> pkr...@unwiredltd.com -- AF mailing list <mailto:AF@af.afmug.com> AF@af.afmug.com <http://af.afmug.com/mailman/listinfo/af_af.afmug.com> http://af.afmug.com/mailman/listinfo/af_af.afmug.com
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