Mike, you are certainly correct about the propagation characteristics. This is both good and bad depending on how people plan to deploy. I think that a lot of people are thinking that this space will let you have a self installed, desktop unit because of the NLOS and indoor penetration. My point is that units like these would have trouble on the uplink because they would have low power and possibly negative gain. A yagi, while a good technical solution is visibly unattractive and I know that many of my customers would not allow me to install one. A panel with similar gain characteristics to a yagi will be large (compared to what people are used to) at these frequencies, again a barrier to overcome to convince some customers. I'm not arguing either...30m is way out there, but 24x24 panel is not, and would probably still be pretty low gain, depending on if it is a patch, array of dipoles, or whatever. That size antenna on the roof will be a turn off to a lot of customers. Also, on the towers, to get decent gain (assuming that the power limitations will be very low) on a linearly polarized, broad beam antenna, the antenna will be larger than anything people have seen to date. Yagi's and lp's won't work here. Again a lot will depend on how the networks are designed and deployed, but my feeling is that because of the (assumed) power constraints that will most likely be placed on the band, and the size limitations that will be a necessity on the towers, a given network may well end up with more towers, not fewer as one would assume because of the better propagation characteristics. Lower frequency is not the end all panacea that many are hoping for.
Regards, Cameron Mike wrote: > 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" <g...@aeronetpr.com> >>>> Reply-To: WISPA General List <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 >>>>> g...@aeronetpr.com >>>>> Aeronet Wireless Broadband Corp. >>>>> 787.273.4143 >>>>> -----Original Message----- >>>>> From: 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" <jun...@ask-wi.com> >>>>>> Sent: Thursday, October 22, 2009 11:49 AM >>>>>> To: "WISPA General List" <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 >>>>> >>>>> >>>>>>> providers to figure out whether there is enough spectrum in a >>>>>>> >>>>>>> >>>>> potential >>>>> >>>>> >>>>>>> service area to make it economically viable. >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>> ------------------------------------------------------------------------ >>>>> ---- >>>>> ---- >>>>> >>>>> >>>>>>> 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/ >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>> -- >>>>>> Jack Unger - President, Ask-Wi.Com, Inc. >>>>>> Author - "Deploying License-Free Wireless WANs" >>>>>> Serving the Broadband Wireless Industry Since 1993 >>>>>> www.ask-wi.com 818-227-4220 jun...@ask-wi.com >>>>>> >>>>>> Sent from my Pizzicato PluckString... >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>> ------------------------------------------------------------------------ >>>>> ---- >>>>> ---- >>>>> >>>>> >>>>>> 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/ >>>>> --- >>>>> [This E-mail scanned for viruses by Declude Virus] >>>>> >>>>> >>>>> >>>>> >>>> Wireless High Speed Broadband service from Info-Ed, Inc. as low >>>> >> as $30.00/mth. >> >>>> Check out www.info-ed.com/wireless.html for information. >>>> >>>> >>>> >>>> >> -------------------------------------------------------------------------------- >> >>>> 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/ >> > > > > > -------------------------------------------------------------------------------- > 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/
