With standard FSK Canopy (7/14 Mbps) you can re-use frequencies on back-to-back sectors only. There is no throughput hit for doing so.
Think about what the GPS sync does- it causes all AP transmission timeslots to occur simultaneously, and all receive timeslots to be synchronized. So colocated APs will never be receiving while another is transmitting, avoiding self-interference. However, SMs receiving from a transmitting AP cluster must have enough separation between APs transmitting on the same frequency so that the signal from the desired AP is above the minimum SNR for the given modulation (10 dB for 2x mode) when compared to another AP transmitting on the same frequency. This can be achieved with a standard Canopy AP module by placing them back to back--the front/back ratio on the antennas provides more than 10 dB isolation. But a SM placed at the edge of two 60 degree sectors wouldn't have nearly enough isolation between the two sectors if they were running on the same frequency to maintain an acceptable SNR. So in short, you need three channels to run a standard 6 AP sector GPS sync'd with Canopy. Patrick Shoemaker Vector Data Systems LLC [email protected] office: (301) 358-1690 x36 http://www.vectordatasystems.com Mike Hammett wrote: > Going in a different direction... > > Can you reuse a given frequency on every sector around a tower (4x or > 6x), or are you limited to something less than that? Do you get full > capacity on each sector, or are you limited to some percentage of that > full capacity if you use the same channel all the way around? > > ----- > Mike Hammett > Intelligent Computing Solutions > http://www.ics-il.com > > > > On 6/14/2010 11:19 AM, Mike Hammett wrote: >> Other than Canopy, what systems also use GPS sync? >> > > > -------------------------------------------------------------------------------- > 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/
