I love the dialog. The 34" antenna is a LPDA and wide band. There is going to have to be segmentation in the bands. Very few antenna systems have the wide band characteristics of a log periodic. Maybe that WILL be the normal antenna for the new technology, but it is quite easy to make other types of gain antennas with a smaller footprint. Kind of like we have different versions of 5 GHz antennas, there will no doubt be specific choices for specific portions of the spectrum.
Thanks guys for sharing the height thing. Such restrictions on the "production" plan won't work. If the goal is to allow such use in an urban setting, the modulation technique would have to be able to survive severe multipath. I'll have to think about the AP on the ground and the client on the roof. Does that make sense? It would certainly keep interference to the AP down. Mike At 02:22 PM 10/23/2009, Mike Hammett wrote: >Due to the number of channels and the likelihood of channel bonding, there's >not going to be an antenna that covers from 692 - 698 MHz, then another that >covers 686 - 692 MHz. it also depends on the area. Maybe the broadcasters >are all sitting on channels 35 - 50, forcing you to use the lower UHF and >VHF channels. It is possible (hopefully) that we'll have gear that does 3, >4, 5 channels bonded together. > >http://www.winegarddirect.com/cview.asp?d=winegard-television-(tv)-antennas&c=UHF%20Only%20Antennas > >That page will have antenna sizes and gains for TV UHF and VHF antenna. > >A 22"x34" only has a 9 - 11.5 dB gain. >A 32"x27"x93" only has 12 - 16 dB gain. > >Those are only UHF. > > >----- >Mike Hammett >Intelligent Computing Solutions >http://www.ics-il.com > > > >-------------------------------------------------- >From: "Mike" <m...@aweiowa.com> >Sent: Friday, October 23, 2009 2:06 PM >To: "WISPA General List" <wireless@wispa.org> >Subject: Re: [WISPA] Holy cow! > > > Jack: > > > > If your goal is to use VHF frequencies at 54 MHz then YES you will > > need a large radiator! If your goal is to use UHF frequencies at > > 300, or 500 MHz, then NO, you won't need a 'TV sized" antenna. If > > *MANY* 6 MHz wide allocations are made, then one would be stupid to > > use a "do all" antenna for all frequencies. Maybe I am missing > > something here. Perhaps a newly revised rules of physics? > > > > Mike Hammett, I am not just trying to be contrary but am willing to > > learn. UHF antennas are *MUCH* smaller than VHF antennas. > > > > Mike > > > > At 01:50 PM 10/23/2009, you wrote: > >>Mike, > >> > >>You are correct. I'm deep into a final review of WISPA's Spectrum > >>for Broadband FCC filing right this minute (well, actually all > >>morning) but I plan to respond to Mike's points with more > >>information that he may not have about the TV White Spaces FCC > >>rules. I think once he has that additional information, he will > >>understand why your (and my) conclusion about needing a "TV-sized" > >>antenna is correct. > >> > >>jack > >> > >> > >>Mike Hammett wrote: > >>> > >>>The 30 meter antenna was misconstrued from the antenna height > >>>requirements. > >>>It's required to be 10 meters or above for CPE use and no higher than 30 > >>>meters for AP use. > >>> > >>>Why would a TV antenna or a TVWS antenna on the same frequency be any > >>>different in size? Maybe some missing elements if your antenna only > >>>covers > >>>part of the band, but a full band antenna should be roughly the same size > >>>as > >>>current TV antenna. We have the use of 54 - 698 MHz (with the current > >>>rule > >>>set, minus a few reserved channels). > >>> > >>>Unless I'm missing something, which I doubt because Jack and I discussed > >>>this at FISPA. > >>> > >>> > >>>----- > >>>Mike Hammett > >>>Intelligent Computing Solutions > >>><http://www.ics-il.com>http://www.ics-il.com > >>> > >>> > >>> > >>>-------------------------------------------------- > >>>From: "Mike" <mailto:m...@aweiowa.com><m...@aweiowa.com> > >>>Sent: Friday, October 23, 2009 1:10 PM > >>>To: "WISPA General List" <mailto:wireless@wispa.org><wireless@wispa.org> > >>>Subject: Re: [WISPA] Holy cow! > >>> > >>> > >>>> > >>>>Well the comments I've heard ARE ludicrous. Antennas as big as a TV > >>>>antenna, 30 meter antennas, and others. > >>>> > >>>>Free space path loss is greater at 5.8 GHz than at 2.4 > >>>>GHz. Substantially. Free space path loss at 700 MHz, or 600 or 500 > >>>>is also SUBSTANTIALLY lesser than at 2.4 GHz. > >>>> > >>>>Free space path loss is proportional to the square of the distance > >>>>between the transmitter and receiver, and also proportional to the > >>>>square of the FREQUENCY of the radio signal. > >>>> > >>>>The FREQUENCY effect of the free space path loss is directly coupled > >>>>to the aperture of the antenna, which describes how sensitive an > >>>>antenna is to an incoming electromagnetic wave for which it is > >>>>resonant. Lower frequency equates to a larger aperture, and a larger > >>>>capture area for similar antennas, as compared to a much higher > >>>>frequency. > >>>> > >>>>If it is indeed a narrow band, then of course the chances of self > >>>>interference are there. The propagation characteristics of UHF for > >>>>fixed wireless are what cause me to want to "play" in this band > >>>>instead of some new allocation in the microwave regions. Think > >>>>through the trees, over the horizon, near line of site possibilities. > >>>> > >>>>You also can't just reinvent the Yagi-Yuda or log periodic antenna > >>>>either. The sizes I stated for those frequencies ARE the full size > >>>>of an antenna, not some miniaturized or "rabbit ear" antenna. > >>>> > >>>>Actually, I don't even think I'm arguing anything, just trying to > >>>>dispel a belief that white space antennas are these huge > >>>>monstrosities; they aren't. > >>>> > >>>>For what it's worth, my personal record for distance on UHF is around > >>>>44,000 miles. REALLY! > >>>> > >>>>Mike > >>>> > >>>>At 12:20 PM 10/23/2009,Cameron wrote: > >>>> > >>>>> > >>>>>It is not "ludacrous". Sure you can receive with a small yagi or panel > >>>>>or heck, even a set of rabbit ears. It's the uplink that will be the > >>>>>major issue. If you are using small cells for coverage you can probably > >>>>>get away with "smaller" antennas on the towers, but this will limit > >>>>>your > >>>>>uplink capability if you are wanting a desktop type CPE or even a small > >>>>>roof mount antenna. Small cell coverage like with uW freqs will have to > >>>>>be carefully planned due to the propagation characteristics and the > >>>>>potential for self interfernece on such a narrow band. It's not > >>>>>impossible, just more complicated. > >>>>> > >>>>>Cameron > >>>>> > >>>>>Mike wrote: > >>>>> > >>>>>> > >>>>>>At 704 MHz, a quarter wave is about 4 inches long. The driven > >>>>>>element of a Yagi would be about 8 inches long. They would be way > >>>>>>shorter than 30 meters, or what do you mean? Think about the 900 MHz > >>>>>>antennas you see but just a little bigger for the upper UHF white > >>>>>>space. > >>>>>> > >>>>>>Ch 52 is 698 MHz. Ch 69 is 800 MHz. Some of the talk I've seen > >>>>>>about enormous antennas in the "white space" is ludicrous. > >>>>>> > >>>>>>Give me ANY part of it and the radios to use it and I > >>>>>>will. Propagation would be superior to anything we're using now. > >>>>>> > >>>>>>Mike > >>>>>> > >>>>>> > >>>>>>At 07:46 PM 10/22/2009, you wrote: > >>>>>> > >>>>>> > >>>>>>> > >>>>>>>What equipment are they using? Did they have to do the 30 meter > >>>>>>>antennas? > >>>>>>> > >>>>>>>Scottie > >>>>>>> > >>>>>>>---------- Original Message ---------------------------------- > >>>>>>>From: "Gino Villarini" <mailto:g...@aeronetpr.com><g...@aeronetpr.com> > >>>>>>>Reply-To: WISPA General List > >>>>>>><mailto:wireless@wispa.org><wireless@wispa.org> > >>>>>>>Date: Thu, 22 Oct 2009 12:05:22 -0400 > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>>> > >>>>>>>>IIRC, 6 mhz channels were proponed on the FCC RO, you could bond > >>>>>>>>them... > >>>>>>>>so with current OFDM technologies you can get 10 - 12 Mbps on a 6 > >>>>>>>>mhz > >>>>>>>>channel. > >>>>>>>> > >>>>>>>>Not bad for a NLOS, self install and mobile probability > >>>>>>>> > >>>>>>>>Gino A. Villarini > >>>>>>>><mailto:g...@aeronetpr.com>g...@aeronetpr.com > >>>>>>>>Aeronet Wireless Broadband Corp. > >>>>>>>>787.273.4143 > >>>>>>>>-----Original Message----- > >>>>>>>>From: > >>>>>>>><mailto:wireless-boun...@wispa.org>wireless-boun...@wispa.org > >>>>>>>>[mailto:wireless-boun...@wispa.org] > >>>>>>>>On > >>>>>>>>Behalf Of Scott Carullo > >>>>>>>>Sent: Thursday, October 22, 2009 11:58 AM > >>>>>>>>To: WISPA General List > >>>>>>>>Subject: Re: [WISPA] Holy cow! > >>>>>>>> > >>>>>>>> > >>>>>>>>My question is how fast can their internet go using tv whitespace? > >>>>>>>>Sprint > >>>>>>>>used to serve this area with an unutilized tv channel and it was > >>>>>>>>SLOW. > >>>>>>>>I > >>>>>>>>guess if you had nothing else but if it can't go one MB its not on > >>>>>>>>my > >>>>>>>>radar > >>>>>>>>of concern. Actually in our market if you cant deliver 10-20MB your > >>>>>>>>not > >>>>>>>> > >>>>>>>>playing the game. > >>>>>>>> > >>>>>>>>Scott Carullo > >>>>>>>>Brevard Wireless > >>>>>>>>321-205-1100 x102 > >>>>>>>>-------- Original Message -------- > >>>>>>>> > >>>>>>>> > >>>>>>>>> > >>>>>>>>>From: "Jack Unger" <mailto:jun...@ask-wi.com><jun...@ask-wi.com> > >>>>>>>>>Sent: Thursday, October 22, 2009 11:49 AM > >>>>>>>>>To: "WISPA General List" > >>>>>>>>><mailto:wireless@wispa.org><wireless@wispa.org> > >>>>>>>>>Subject: Re: [WISPA] Holy cow! > >>>>>>>>> > >>>>>>>>>See the attached Case Study and Press Release. > >>>>>>>>> > >>>>>>>>>jack > >>>>>>>>> > >>>>>>>>> > >>>>>>>>>Jonathan Schmidt wrote: > >>>>>>>>> > >>>>>>>>> > >>>>>>>>>> > >>>>>>>>>>Dell, Microsoft Launching Broadband Net In Rural Virginia > >>>>>>>>>>Computer Companies Join TDF Foundation, Spectrum Bridge To Debut > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>Network > >>>>>>>> > >>>>>>>> > >>>>>>>>>> > >>>>>>>>>>Using 'White Spaces' > >>>>>>>>>> > >>>>>>>>>>John Eggerton -- Multichannel News, 10/21/2009 3:47:19 PM > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>>>>Computer companies Dell and Microsoft are scheduled to join with > >>>>>>>>>>TDF > >>>>>>>>>>Foundation and Spectrum Bridge Wednesday to launch a broadband > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>network > >>>>>>>>in > >>>>>>>> > >>>>>>>> > >>>>>>>>>> > >>>>>>>>>>rural Virginia, using the so-called white spaces between TV > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>channels. > >>>>>>>> > >>>>>>>> > >>>>>>>>>> > >>>>>>>>>>House Communications Subcommitee Chairman Rick Boucher, who > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>represents > >>>>>>>> > >>>>>>>> > >>>>>>>>>> > >>>>>>>>>>rural Virginia, is scheduled to be on hand as the companies host a > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>Webcast > >>>>>>>> > >>>>>>>> > >>>>>>>>>> > >>>>>>>>>>with residents of an Appalachian community talking about how > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>wireless > >>>>>>>> > >>>>>>>> > >>>>>>>>>> > >>>>>>>>>>Interent connectivity can change their lives. > >>>>>>>>>> > >>>>>>>>>>The government is currently working on a national broadband plan, > >>>>>>>>>>including freeing up even more spectrum space for wireless > >>>>>>>>>>Internet. > >>>>>>>>>> > >>>>>>>>>>Spectrum Bridge, a sort of Ebay for identifying available spectrum > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>in > >>>>>>>> > >>>>>>>> > >>>>>>>>>> > >>>>>>>>>>secondary markets, launched a Web site in February to help > >>>>>>>>>>identify > >>>>>>>>>>available open TV channels. The site can be used by wireless > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>>Internet > >>>>>>>> > >>>>>>>> > >>>> > > >-------------------------------------------------------------------------------- >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/
