Ruckus Wireless has beamforming (i.e. smart antenna technology)... does it on a packet by packet basis. But it's a WiFi system (although from what I understand its being deployed overseas now in Muni-Wifi situations... I just proposed to someone using Ubquity Nanostations to them).
Daniel White 3-dB Networks http://www.3dbnetworks.com >-----Original Message----- >From: [email protected] [mailto:[email protected]] On >Behalf Of Marlon K. Schafer >Sent: Sunday, November 01, 2009 2:40 PM >To: WISPA General List >Subject: Re: [WISPA] Backhaul Questions > >Correction, under the 3 for one rule you can go UP 3 dB in antenna gain >for every 1 dB of radio transmit power that you go down, but only for >client side or ptp installations. It STARTS at 30 dB radio and 6dB >antenna. > >So if you have a 30dB radio, it's a 6dB antenna. 29dB radio you can use >a 9dB antenna. > >28-12 >27-15 >26-18 >25-21 >24-24 >This is the one that excited me years ago. This meant I could use a >quarter watt amp, 24dB with a 24dB grid for a ptp link! That'll give >you a -72dB rssi (54 meg speeds!) at 100 miles! Get this one, -78dB >rssi at 200 (not a typo, two HUNDRED MILES)! I love big antennas! grin > >Again, this is only for 2.4 client side installs (radio only talks to >ONE other radio). > >There is a bit of an exception to this rule based on smart antenna >technology. One that no one has successfully used (as far as I know). >Vivato and Nivini tried. We (WISPA) did get the FCC to issue a written >interpretation of the rules allowing us to use routed AP's as a >substitute for active beam steering systems (in the end it has the same >effect). > >In theory we COULD ring a building with 24dB grid antennas with 24dB >radios for a 42 WATT system and still be within the power level rules. >In reality though, antennas are too "leaky" and you'd be hard pressed to >avoid massive self inflicted interference. I always wanted to try >building a system like this though! grin. (disclaimer, it's been a >while since I studied that part of the rules, the max output power could >be lower than 42 watts.....) > >laters, >marlon > > ----- Original Message ----- > From: Jack Unger > To: WISPA General List > Sent: Sunday, November 01, 2009 12:17 PM > Subject: Re: [WISPA] Backhaul Questions > > > EIRP is a TRANSMIT number. "Equivalent isotropic RADIATED power". This >is the radiated power on transmit in dBm leaving the transmit antenna in >the favored direction compared to the power that would be radiated if 1 >milliwatt (0 dBm) were fed into a theoretical isotropic antenna that had >0 dBi (no) gain in any direction. > > EIRP = TX power (minus) transmission line loss (plus) antenna gain = >EIRP > > Further, > > 2.4 GHz allows more than 6 dBi antennas even with 1-watt radios under >the "3:1" rule for point-to-point use. This is why CPE can run more than >+36 dBm because the CPE are effectively point-to-point radios talking to >only one access point. The AP is NOT a point-to-point radio therefore it >is limited a maximum EIRP of +36 dBm. > > 5.8 GHz allows more than 6 dBi antennas with 1-watt radios for point- >to-point use. That's how those long 5.8 GHz backhauls can be made to >work reliably. > > jack > > > > Marlon K. Schafer wrote: >Yeah. > >People all too often forget that eirp is a RECEIVE number not a TRANSMIT >number. All it takes is big, big ears and you can hear the other end >from a >very long ways away. Makes for much less noise in the area too. > >I hate the trend toward high power radios with low power antennas. > >You guys do realize that 2.4, 900 and 5.8 gig bands limit you to a 6 >(that's >S-I-X) dB antenna if you use a 1 watt (30 dB) radio? Base station >especially. For CPE you can use higher gain cpe antennas on 5 gig and >still >be OK within the rules. > >But all of these stupid, noisy, wasteful, cpe systems with 1 watt radios >and >19dB panels make a mess of your networks. (and mine) > >marlon > >----- Original Message ----- >From: "Mike Hammett" <[email protected]> >To: "WISPA General List" <[email protected]> >Sent: Saturday, October 31, 2009 10:50 AM >Subject: Re: [WISPA] Backhaul Questions > > > 30 dB EIRP with a 44 DBi antenna on each side over 73 miles produces - >75 >signal. I'll let him say what he did to make it work, but it's >certainly >possible. > > >----- >Mike Hammett >Intelligent Computing Solutions >http://www.ics-il.com > > > > >From: Bret Clark >Sent: Saturday, October 31, 2009 11:02 AM >To: WISPA General List >Subject: Re: [WISPA] Backhaul Questions > > >Man...what is the EIRP on these links that people are posting high bit >rates? As someone else stated, gotta wonder if the FCC won't start >getting >suspicious at some point. > >Travis Johnson wrote: > 73 miles... and I get 28Mbps total (14Mbps each direction) using a >20mhz >channel. > > Travis > > > Josh Luthman wrote: >Travis is getting 28 megs on a really long backhaul - like 58 miles? > >You will not see >30. > >On 10/31/09, Eric Rogers <[email protected]> wrote: > Ok guys...Looking for both Mikrotik experience and others. We >currently >have a Mikrotik backhaul between each of our towers using NStreme and we >have been extremely happy with the performance. We recently upgraded a >tower because we were hitting 15M or so during peak times and was afraid >it couldn't handle much more. We upgraded that backhaul to a Motorola >PTP for future capacity. > > > >The questions: > > > >MT Gurus: > >Each backhaul ranges in distance, each ranges from 3 miles (3 backhauls) >and the rest are about 12 miles (5 backhauls). Since we have been using >Mikrotik, I have reliably seen up to 10 Meg, and I am afraid 15 Meg is >pushing the envelope on a 20 MHz channel. > > > >How much capacity can I reliably push on a 20 MHz channel using NStreme? > > > >Other Gurus: > >I understand the following are loaded questions, but budget is around >$1000-3000 range and the capacity needs to be around the 60Meg mark (30 >each way or without a defined 1:1 guarantee, capability to flex and be >able to push 30M each way). > > > >If I start upgrading to larger backhauls on busy links, what type of >equipment should I look at? > >What can support VoIP? > >Anything that GPS times for frequency reuse? > >Anything work in the 5.4GHz range at a 12 mile distance? > > > >Eric Rogers > >Precision Data Solutions, LLC > >(317) 831-3000 x200 > > > > > >------------------------------------------------------------------------ >-------- >WISPA Wants You! Join today! >http://signup.wispa.org/ >------------------------------------------------------------------------ >-------- > >WISPA Wireless List: [email protected] > >Subscribe/Unsubscribe: >http://lists.wispa.org/mailman/listinfo/wireless > >Archives: http://lists.wispa.org/pipermail/wireless/ > > > > ----------------------------------------------------------------------- >------- > > >------------------------------------------------------------------------ >-------- >WISPA Wants You! Join today! >http://signup.wispa.org/ >------------------------------------------------------------------------ >-------- > >WISPA Wireless List: [email protected] > >Subscribe/Unsubscribe: >http://lists.wispa.org/mailman/listinfo/wireless > >Archives: http://lists.wispa.org/pipermail/wireless/ > > > >------------------------------------------------------------------------ >-------- > > > > >------------------------------------------------------------------------ >-------- >WISPA Wants You! Join today! >http://signup.wispa.org/ >------------------------------------------------------------------------ >-------- > >WISPA Wireless List: [email protected] > >Subscribe/Unsubscribe: >http://lists.wispa.org/mailman/listinfo/wireless > >Archives: http://lists.wispa.org/pipermail/wireless/ > > >------------------------------------------------------------------------ >-------- >WISPA Wants You! Join today! >http://signup.wispa.org/ >------------------------------------------------------------------------ >-------- > >WISPA Wireless List: [email protected] > >Subscribe/Unsubscribe: >http://lists.wispa.org/mailman/listinfo/wireless > >Archives: http://lists.wispa.org/pipermail/wireless/ > > > >------------------------------------------------------------------------ >-------- >WISPA Wants You! Join today! >http://signup.wispa.org/ >------------------------------------------------------------------------ >-------- > >WISPA Wireless List: [email protected] > >Subscribe/Unsubscribe: >http://lists.wispa.org/mailman/listinfo/wireless > >Archives: http://lists.wispa.org/pipermail/wireless/ > > > > >-- >Jack Unger - President, Ask-Wi.Com, Inc. >Author - "Deploying License-Free Wireless WANs" >Serving the Broadband Wireless Industry Since 1993 >www.ask-wi.com 818-227-4220 [email protected] > >Sent from my Pizzicato PluckString... > > > > > >------------------------------------------------------------------------ >------ > > > > > ---------------------------------------------------------------------- >---------- > WISPA Wants You! 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