I think we may see some panels become available in the 12-13+ dB range but more like 15-18 inches.
The thing about gain is that once you reach FCC allowed EIRP of +36 dBm, and if SNR is limited by interference not receiver noise floor, there is no advantage to more antenna gain except the narrower beamwidth that comes with it. But people have found that shooting through foliage, high gain and narrow beam doesn’t always help. So for NLOS it’s hard to say if 12 dBi is better than 10 dBi. I will say that sidelobe and especially F/B performance is important. We often run into situations where a strong interferer is behind the customer, and a lot of 900 MHz antennas have poor F/B ratio. So when I hear 12 dBi gain in 14 inches, I wonder if other specs like F/B have to be compromised. For example, MTI makes an 18 inch single pol panel, big and expensive, but it has very good specs. The reason I say 12 inches is it’s difficult for us to mount an 18 inch panel, or a 3-5 ft yagi, at many installations. Especially if we are retrofitting an installation with a smaller panel, integrated or external. A 14 inch panel would actually be 20 inches to the corners assuming a diamond shape. Ideally there would be both a compact solution, and a higher gain solution. A bracket to hold the 450i SM, at a location where the coax jumpers dress nicely to the SMA jacks on the top of the SM, would also be a big plus. The Cambium dual pol yagi has the bracket, I’m just very dubious about those things with the snow and ice we get here, I’m pretty sure they would get fouled with wet snow a lot. We just had one of those snowstorms, and trees that still had leaves lost a lot of branches from the weight of the snow. From: Chuck McCown Sent: Wednesday, November 25, 2015 9:32 AM To: [email protected] Subject: Re: [AFMUG] PMP450i 900MHz How about a 14 inch 12 dBi panel? From: Ken Hohhof Sent: Tuesday, November 24, 2015 9:40 PM To: [email protected] Subject: Re: [AFMUG] PMP450i 900MHz MSRP is $89. Not difficult to figure out street price. I can get two TY-900s for $280. But spatial diversity! And gold! Actually, I wish there was a 12 inch 10 dBi panel, like a dual pol version of this: https://www.tessco.com/products/displayProductInfo.do?sku=474662 From: Chuck McCown Sent: Tuesday, November 24, 2015 10:13 PM To: [email protected] Subject: Re: [AFMUG] PMP450i 900MHz When someone discovers the street price of this thing, please let me know. From: Sriram Chaturvedi Sent: Tuesday, November 24, 2015 6:44 PM To: [email protected] Subject: Re: [AFMUG] PMP450i 900MHz Hi Eric, Yes. We offer an official Cambium dual polarity yagi. More info here: http://www.cambiumnetworks.com/products/accessories/pmp450-900mhz-directional-antenna/ 900 MHz Directional Antenna - cambiumnetworks.com 900 MHz Directional Antenna. Details on the PMP 450i 900 MHz directional antenna. Read more... Thanks, Sriram -------------------------------------------------------------------------------- From: Af <[email protected]> on behalf of Eric Kuhnke <[email protected]> Sent: Tuesday, November 24, 2015 7:37 PM To: [email protected] Subject: Re: [AFMUG] PMP450i 900MHz Is there an 'official' Cambium antenna or recommended antenna for dual polarity 900 MHz yagi? Something like the ubnt dual polarity yagi? On Tue, Nov 24, 2015 at 3:15 PM, Mathew Howard <[email protected]> wrote: Pricing has been available for awhile, APs are the same as the other 450, and SMs are a bit cheaper (considering no they're all uncapped). Last I heard they were saying it will ship late November... which should mean any day now. On Tue, Nov 24, 2015 at 5:01 PM, Ryan Ray <[email protected]> wrote: "We've been testing PMP450i 900MHz for almost a month now and we're really impressed with it. I have a 1.5 mile shot through multiple evergreen and deciduous trees, along with heavy interference in an urban environment (pager /scada noise spikes at around -65dBm across every channel). I get about 25mbps down and 2mbps up on speed tests using a 10MHz channel width. Latency/jitter is good enough for VoIP and gaming. I believe distributors will be shipping radios just after thanksgiving." I found this on DSL reports. Anyone else had any experience with this equipment? How's it looking? Is there any word on pricing or ship times yet?
