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Technology Stocks : CellularVision (CVUS): 2-way LMDS wireless cable. -- Ignore unavailable to you. Want to Upgrade?

To: dwight martin who wrote (986)	2/4/1998 5:32:00 PM
From: Rob Preuss	Respond to of 2063

For any "newbies" who aren't in touch with "LMDS" it might be worth a few minutes of your time to investigate this fixed broadband wireless technology. Here's some starter info, along with a few pointers and some quotes/remarks, which can serve as technology backgrounder. (I'm new to this thread and put this together for other reasons but I thought it might be worth sharing with everyone here.) Rob +++ The FCC has been fooling around with this since 1992. Bandwidth auctions have been delayed several times and are now set for 2/18/98. Cellularvision has already been awarded a "Pioneer License" and is currently offering LMDS services in the New York metropolitan area. cellularvision.com +++ ajs2.com >Local Multipoint Distribution Service (LMDS) uses millimeterwave signals >in the 28 GHz spectrum to transmit voice, video, and data signals within >cells 3-10 miles in diameter. > LMDS is a microwave broadband service that will allow license holders >to control up to 1.3 GHz of wireless spectrum in the 28 GHz Ka-band once >FCC auctions have been completed. The extremely high frequency point to >multipoint transmissions will be "cellular," based on multiple contiguous, >or overlapping cells. The FAQ is quite informative: ajs2.com Among many other things, its states that LMDS has more than 40x the bandwidth of PCS but, unlike PCS, it requires a stationary receiver. Note also that LMDS is strictly LOS between the base station and the fixed receivers (point-to-multipoint). +++ This older (9/30/96) article internettelephony.com seems to have good info including the statement: >* Line-of-sight access. According to Endgate's Lockie, signals at 28 GHz >propagate like "fat laser beams" and may be blocked by foliage. It is best >to communicate above the tree line. HP plans to use line-of-sight >communication from rooftop antennas to elevated hubs. It may be possible >to overcome lack of line-of-sight with increased power, but that brings >its own set of challenges, including possible higher transmitter costs. +++ While Universal ADSL seems like a good near-term offering (of about 1 Mbps to the home) with fairly small infrastructure costs (by using the higher frequencies in standard phone lines to provide a continuous connection without interfering with phone usage), and this can be increased to maybe 5-10Mbps (at the expense of greater infrastructure costs), the longer-term demands for ever-higher bandwidth will continue. LMDS looks like a good candidate to meet this longer-term demand since 1 Gbps is practical and per-user infrastructure costs are low (and getting lower with advances in GAAS semiconductor technology). webcel.com +++ uswavelink.com >Local Multipoint Distribution System (LMDS) is poised to be the dominating force >in fixed wireless applications. The technology can replace existing phone lines, >cable and other infrastructure. LMDS provides, in effect, a single information >stream into the home or business, at significantly lower cost than equivalent >connections today. The technology overcomes the traditional "last mile" problem >in adding bandwidth to existing communications systems and networks. Operating >at between 26 and 30 gigahertz the technology uses a much higher frequency than >most existing wireless applications. +++ uniquesys.com >LMDS Main Advantages > * LMDS technology offers fiber bandwidth wit out the fiber costs > * Cell structure offers efficient coverage of desired locations > * The up front capital investment to set up an LMDS network is > many times lower than land lines > * Point to multipoint capabilities combined with bidirectionality > offers numerous services > * Allows rapid deployment +++ ovum.com >"Wire telegraph is a kind of very very long cat. You pull his tail in New York >and his head is meowing in Los Angeles.... And radio operates exactly the same >way: you send signals here, they receive them there. The only difference is that >there is no cat." - Albert Einstein +++ its.bldrdoc.gov > Study of the Local Multipoint Distribution Service Radio Channel > Published in IEEE TRANSACTIONS ON BROADCASTING, VOL. 43 NO. 2, JUNE 1997 >This paper summarizes radiowave propagation impairments for local multipoint >distribution services (LMDS) and reports measurement data for small cells. >Results include area coverage estimates over a range of basic transmission losses >for 0.5-, 1.0- and 2.0- km suburban cells with foliated trees. Multipath, signal >attenuation, depolarization, and cell to cell coverage also are discussed. Data >indicates a high probability of non-line-of-sight paths due to trees which can >cause signal attenuation and signal variability when wind is present. Signal >variability was studied using k factors and compared to the Rician cumulative >distribution function. Depolarization caused by vegetation and other signal >scatterers was found to be an order of magnitude greater than rain-induced >depolarization. A simple tapped delay line model is presented to describe >multipath for three channel states. +++