On Wed, Nov 05, 2008 at 06:50:45AM -0800, Marlon K. Schafer wrote: > 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.
2.4 is of limited use in scenes like this, where 90% of the houses are not visible from a hilltop or tower. http://www.f64.nu/albums2007/album114/DSC1595.jpg I don't need 50 miles. It would be overloaded in short order unless I charged by the byte like the cell companies. I want 2-6 miles and good woods penetration. I'm kinda pleased the have the new frequencies as unlicensed. Sure licensed lite would be nice, but unlicensed means inexpensive commodity equipment. That used to mean junk, but now, it's now there are diamonds in the rough developing for commodity based unlicensed equipment. > 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/ -- /* Jason Philbrook | Midcoast Internet Solutions - Wireless and DSL KB1IOJ | Broadband Internet Access, Dialup, and Hosting http://f64.nu/ | for Midcoast Maine http://www.midcoast.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/
