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Microcap & Penny Stocks : Globalstar Telecommunications Limited GSAT -- Ignore unavailable to you. Want to Upgrade?

To: djane who wrote (3923)	4/16/1999 8:18:00 PM
From: djane	Respond to of 29987

G/I technical differences (via LOR yahoo thread) Top>Business and Finance>Stocks>Services>Communications Services>LOR (Loral Space & Communications Ltd) Help - Add to My Yahoo! - Sign Out Tahoetech, Crisis, et al by: lorlurker (35+/M/Palo Alto, CA) 13560 of 13561 Well, you guys asked for it by encouraging me, so here is some more rambling on the differences between G* and I. First, look at the difference in orbits and what that implies. G flies at a higher orbit, therefore "sees" more of the Earth at any given time than I. Implication: needs fewer satellites, therefore less cost. Second, G flies at a 52 degrees inclination, while I* flies at about 90 degrees. Implication: I* spends a lot more time over water and unpopulated regions, generating a lot less revenue. Next, I* has at many times only one satellite in view of the user; G* usually has 3, but the range is 2-7 in the heavily populated regions. Implication: I* has a fade-out problem when the user is behind a tree, G* gateways combine the different signals from different sats and can recover from fading very nicely. Next, TDMA vs. CDMA. Hey, I think TDMA is great, but it has real limitations, like needing to know the time delay. When you are talking from a fixed ground station to a GEO bird, the time delay is known. When you are I, and your birds are at slightly different altitudes, and your users are moving and are in sight at various points in view, well, you have to compensate by allocating slop to each signal. Implication: reduced capacity. I think I can only handle 2400 bps, while G* is 9600. I* cannot even send data packets, as I understand it, but only voice. Another implication: I* demods and remods, making the flight electronics much more complicated. More complicated = less reliable. Handsets? I* handset is probably great if you are not getting to the gym regularly and need another form of working out. G, while not the size of a cell phone, is reasonable, and reasonably priced. (Maybe I should market their phones as a health aid <g>). Finally, G* handsets have been and are being tested- so far, so good. Since the first launch the boys at Qcomm have been playing with the sets, and the results are quite a bit better than the press on I*. I know, a bit of a ramble. In my defense, you did encourage me... Posted: 04/16/99, 2:11PM EDT as a reply to: Msg 13557 by tahoetech View Replies to this Message

To: djane who wrote (3923)	4/18/1999 3:01:00 AM
From: djane	Read Replies (1) \| Respond to of 29987

Little LEOs Advocating More Global Spectrum From the April 19, 1999 issue of Wireless Week By Caron Carlson WASHINGTON--Satellite data service providers, known as "little LEOs," will meet this week in Geneva and discuss ongoing efforts to share land mobile radio frequencies. But prospects for an additional allocation in the near term are dim. The little low-Earth orbit satellite operators long have eyed the 450 MHz band for expansion, which is heavily used by private wireless and other land mobile operators. Having received an international allocation in 1997 to share 2 megahertz of the band--455-456 MHz and 459-460 MHz--in North and South America, they hope to extend the allocation globally. This week the International Telecommunication Union's working party on mobile satellite services will make further preparations for the ITU's World Radiocommunications Conference in 2000. Global use of the 1997 allocation would require authorization to use it in Europe and Asia, where there has been less enthusiasm for it. The 455-456 MHz and 459-460 MHz bands are currently used by TV broadcasters for remote newsgathering. Broadcasters are fighting the FCC's implementation of the ITU allocation, but land mobile radio operators in the United States have not objected to it. However, land mobile users are concerned that the satellite operators have gained a foothold in the 450 MHz band, and they oppose any little LEO efforts to share other parts of the band. "The land mobile community remains concerned about interference potential from the little LEOs," said Mike Lewis, engineering consultant with the law firm of Wiley, Rein & Fielding. "The little LEOs have long sought spectrum through the international process, and mostly land mobile spectrum." While sharing may be feasible in the frequencies used by broadcasters, it is not palatable to the land mobile community because of the different way the frequencies will be used, licensing processes and loading situations in their spectrum, said Thomas Keller, attorney for the Association of American Railroads. Although the little LEOs have presented extensive sharing studies to support their efforts, the studies do not satisfy land mobile operators. "All of the spectrum sharing studies end up with the admission that [little LEOs] will cause interference," he said. "They say it will be minimal, but any interference can be detrimental." Many sensitive communications in the land mobile bands require real-time dispatch and absolute control, Keller added. Although he sees no imminent threat to these communications from satellite operators, Keller said it is important to monitor the international discussions closely. The little LEOs themselves are less than hopeful that the ITU will authorize more shared spectrum before the systems already licensed use it to capacity. "We advocate additional spectrum, but we are not optimistic it will come in 2000," said Teresa Jay, director of business development for LEO One USA. "We certainly have enough spectrum to deliver the services we've promised." \| Home Page \| Site Map \| Search Archive \| PowerSearch \| \| International \| Wireless Web Sites \| Hot Stories \| Please send comments and suggestions on this Web site to jcollins@chilton.net Wireless Week, 600 S. Cherry St., #400, Denver, CO 80246 Voice: 303-393-7449, Fax: 303-399-2034 Published by Cahners Business Information © Copyright 1999. All rights reserved.