Something still isn't working out for me... I'm coming up with just under 200db of free space loss for geosynchronous orbit... 30dBm txpower + 25dBi antenna + 25dBi antenna - 200db free space loss, gets me a signal of -120, that just isn't going to work!
On Tue, Feb 23, 2016 at 5:11 PM, Chuck McCown <[email protected]> wrote: > Yep, the sheet I was looking at didn’t say that. So yes. > > So feel free to use it out to 77,625 miles. > > You can use it for geosynchronous orbit with some fade margin! > > *From:* Mathew Howard <[email protected]> > *Sent:* Tuesday, February 23, 2016 4:09 PM > *To:* af <[email protected]> > *Subject:* Re: [AFMUG] Fw: Force 200 Ptp distance > > I see now, I was confused where the 158 was coming from... but the Force > 200 spec sheet says the antenna is 25dBi and trasmit power is up to > 30dBm... so, shouldn't that get us 173? > > On Tue, Feb 23, 2016 at 5:04 PM, Chuck McCown <[email protected]> wrote: > >> 22 dBm transmit power with a 23 dBi integrated antenna == 45 dBm EIRP >> RX sensitivity, adaptive = –93 dBm. >> To me that would be a system gain of only 138 dB. >> Oh, but you have to add the RX antenna, so another 23 dBi and you get 158 >> dB. >> >> There ya have it. >> >> *From:* Chuck McCown <[email protected]> >> *Sent:* Tuesday, February 23, 2016 4:01 PM >> *To:* [email protected] >> *Subject:* Re: [AFMUG] Force 200 Ptp distance >> >> If you max out the EIRP and go for minimum usable RX signal level, >> Cambium says that difference is 158 dB. >> (system gain) >> >> The rest is a free space path loss formula run backwards. >> >> *From:* Craig House <[email protected]> >> *Sent:* Tuesday, February 23, 2016 3:58 PM >> *To:* [email protected] >> *Subject:* Re: [AFMUG] Force 200 Ptp distance >> >> I understood it perfectly. Up to the period after sheet . It got a bit >> fuzzy after that. >> Craig >> >> >> ------------------------------ >> *From: *"Mathew Howard" <[email protected]> >> *To: *"af" <[email protected]> >> *Sent: *Tuesday, February 23, 2016 4:57:33 PM >> *Subject: *Re: [AFMUG] Force 200 Ptp distance >> >> Your math confuses me... >> >> On Tue, Feb 23, 2016 at 4:52 PM, Chuck McCown <[email protected]> wrote: >> >>> 158 dB using 23 dBi integrated antenna according to the spec sheet. >>> >>> 158=20 log D + 20 log 5800 >>> 7.9=log D +3.76 >>> 4.14=log D >>> >>> 10 to the 4.14 power = 13,804 miles >>> >>> *From:* Joseph Marsh <[email protected]> >>> *Sent:* Tuesday, February 23, 2016 3:45 PM >>> *To:* [email protected] >>> *Subject:* [AFMUG] Force 200 Ptp distance >>> >>> >>> What is the max distance for a force 200 Ptp link? >>> >> >> >> > >
