Charles, What equipment did you use to build up your WISP? Also what did you start with and what did you end up with?
Kurt Fankhauser WAVELINC 114 S. Walnut St. Bucyrus, OH 44820 419-562-6405 www.wavelinc.com -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Charles Wu Sent: Tuesday, January 17, 2006 6:55 PM To: 'WISPA General List' Subject: RE: [WISPA] Multiple Radios on Single antenna Hi, I would recommend that you do some research on the terms "dynamic range" and "front-end compression" as it relates to your particular hardware / radio platform. Understanding those terms / concepts will give you the understanding you need to make your "homebrew" system work Otherwise, if you want to just "plug and pray" your network -- you're better off probably just buying quality name brand products that have enough built-in "safeties" to let one just mindlessly deploy -Charles P.S. -- although I happen to have an understanding of Rf theory, HAM stuff, and Radio engineering, when I ran my WISP, I found that in the long run, it made better business sense to subscribe to a "lazy" WISP "plug-and-pray" mentality due to the fact that I liked knowing that I could focus my core efforts on sales, marketing and customer service. From a deployment side, I could just put some stuff up and have the ability to blame all my system mishaps on my friendly manufacturer / vendor =) ------------------------------------------- WiNOG Austin, TX March 13-15, 2006 http://www.winog.com -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bob Moldashel Sent: Tuesday, January 17, 2006 6:25 PM To: WISPA General List Subject: Re: [WISPA] Multiple Radios on Single antenna Ahhhhh......Lets do some math....... Lets say the radio has a +20 dB output. For this example there is no line loss. The antenna is rated at 30dB x-pole isolation. Here we go... +20 dB -30dB xpole = -10 dB receive level. In my book that is high enough to kill any link of the same freq on the opposite polarity....No??? Add to that a radio that needs to Rx and Tx on and off and you should have receiver blocking....... -B- Matt Liotta wrote: > Depending on various factors, you should see at least 15db of > attenuation between polarizations on a dual-pol antenna. > Theoretically, you should see 20db. In any case, 15db is enough > attenuation even on the same channel to operate two links reliably. > > -Matt > > Jason Wallace wrote: > >> List, >> >> When antennas are separated by normal distances, they can only "see" >> each other electromagnetically (ie, radio waves). However, when they >> are close they will experience capacitive and inductive coupling. >> Dual pol antennas work fine when only receiving (as in those large >> satellite dishes from the 80's that used 90° pol changes between >> adjacent channels). I think you will always have trouble overloading >> the receiver when transmitting with this setup. > > > -- Bob Moldashel Lakeland Communications, Inc. Broadband Deployment Group 1350 Lincoln Avenue Holbrook, New York 11741 USA 800-479-9195 Toll Free US & Canada 631-585-5558 Fax 516-551-1131 Cell -- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/ -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.371 / Virus Database: 267.14.18/230 - Release Date: 1/14/2006 -- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
