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" <wireless@wispa.org> 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" <wireless@wispa.org> > 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: wireless@wispa.org >> >> 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: wireless@wispa.org > > 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: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
