16dB by 120* won't have much of a vertical pattern will it? I'd guess less than 10*. marlon
----- Original Message ----- From: "Chuck McCown" <[EMAIL PROTECTED]> To: "WISPA General List" <[email protected]> Sent: Wednesday, November 05, 2008 10:43 AM Subject: Re: [WISPA] Theoretical TVWS coverage > No but they will be about 20 feet high for an H pol 600 MHz slotted > waveguide 16 dBi 120 degree sector. > > ----- Original Message ----- > From: "Mike Hammett" <[EMAIL PROTECTED]> > To: "WISPA General List" <[email protected]> > Sent: Wednesday, November 05, 2008 8:36 AM > Subject: Re: [WISPA] Theoretical TVWS coverage > > >>I could see 16 dB sectors. Of course they will be large, but that's what >>it >> takes at these frequencies. We'll have antennas the same size as the >> broadcast TV antennas are now (I've seen some over 40' tall). Hopefully >> a >> manufacturer can work something out with regards to not having to have 4x >> 40' sectors on a tower to provide the needed coverage... that could >> result >> in some tasty rates. >> >> I don't think the number of wifi devices we see is a useful argument. >> Their >> response is 3.65 and 5.4 GHz... plenty of new space and no wifi devices. >> We need to stress the penetration abilities and the need for copious >> amounts >> of spectrum that has these penetration abilities. I believe these lower >> frequencies will help fill in coverage gaps within any given range. We >> may >> not have any more range with TVWS vs. existing bands with equal EIRP >> because >> of smaller antenna requirements, but buildings and trees no longer make >> that >> coverage spotty. >> >> >> ---------- >> Mike Hammett >> Intelligent Computing Solutions >> http://www.ics-il.com >> >> >> >> -------------------------------------------------- >> From: "Marlon K. Schafer" <[EMAIL PROTECTED]> >> Sent: Wednesday, November 05, 2008 8:50 AM >> To: "WISPA General List" <[email protected]> >> Subject: Re: [WISPA] Theoretical TVWS coverage >> >>> Hmmm >>> >>> Just for fun I ran the numbers at 600mhz. >>> >>> 20 dB tx from the radio, 16dB tx antenna (probably not at all reasonable >>> due >>> to size and small 50ish* coverage) to a 10 dB cpe antenna. -80 at 50 >>> miles! >>> >>> Same thing with an 8dB (say omni) would be 20 miles at -80. >>> >>> The sad part though? We can do that with today's wifi gear! 20 miles >>> is >>> pretty easy in the open. >>> >>> Now lets run this at the WISPA 20 WATT level. That's 43dB eirp. >>> >>> So, 35dB tx power and 8dB omni to 10dB cpe antenna. I get -80 at 100 >>> miles! >>> Now we're talkin! >>> >>> The next question that has to be answered. What is the receive signal >>> of >>> the average TV set these days? What does it need to be able to pick up >>> a >>> signal? We need to know that number if we're to come up with a non >>> interfering OOB level that we can suggest to the FCC. >>> >>> This is why people need to join wispa. We have to fight this fight. >>> They >>> are still looking at what to do with us it sounds like. We have to be >>> ready >>> to go back there again. We need to show them pictures of our areas, >>> demographics, screen shots of all of the wifi devices we pick up at our >>> ap's. etc. etc. etc. >>> >>> Pretty cool. >>> marlon >>> >>> ----- Original Message ----- >>> From: "Mike Hammett" <[EMAIL PROTECTED]> >>> To: "WISPA List" <[email protected]> >>> Sent: Wednesday, November 05, 2008 5:12 AM >>> Subject: [WISPA] Theoretical TVWS coverage >>> >>> >>>> Based on TV antenna, it looks like the largest gain CPE will be around >>>> 10 >>>> dB for all but the lowest of frequencies. >>>> >>>> I just ran a Radio Mobile coverage area using a guesstimate at a white >>>> spaces system... EIRP of 20 dBm, 16 dBi sector, 10 dBi CPE, -80 dBm >>>> minimum allowed receive. The range wasn't much more than 2 miles in >>>> flat >>>> country land. >>>> >>>> With those same measurements with a 36 dBm EIRP, we have 10 miles, but >>>> terrain comes more into play here. >>>> >>>> For the extreme rural areas, this is where tower height comes into >>>> play. >>>> For everyone else, this is your foliage beater. In these areas we >>>> still >>>> need small cells for bandwidth capacity and interference rejection. >>>> >>>> Remember, the only signal levels mentioned were 40 mw for personal >>>> portable devices. Anything else is just speculation at this point. >>>> They >>>> may very well give fixed stations 4 W as they do in all other >>>> unlicensed >>>> bands. >>>> >>>> >>>> ---------- >>>> Mike Hammett >>>> Intelligent Computing Solutions >>>> http://www.ics-il.com >>>> >>>> >>>> >>>> -------------------------------------------------------------------------------- >>>> 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! 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