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

To: Rocket Scientist who wrote (9349)	1/7/2000 12:36:00 PM
From: Geoff Goodfellow	Respond to of 29987

Dear RS/CC: My 1 Kc CZK (.028 USD) on Globalstar vs. Iridium "quality differential" is the multi-path wonder of CDMA vs. the single path nature of TDMA. In TDMA you are served by one and only one "cell site" (in the case of the satellite networks that cell site is floating in the heavens above). With TDMA as the signal quality from the subscriber unit degenerates, you need to find another cell site to hand off to. With a satellite system using TDMA this can be caused by the satellite itself zooming along its orbital path and passing you along to the next one as it comes over the horizon. However, if you are obstructed by a building, a mountain, a rock, tree or something else solid between you and the satellite "cell site" you are talking to before the next satellite "cell site" comes along you drop. In CDMA you can be served, or rather "listened to" by multiple "cell sites", and the site that hears you best is the one that your voice comes from. In CDMA this is known as "soft handoff" because you remain on the same frequency/channel, but the primary listening "cell site" changes. With a satellite system using CDMA like Globalstar this multi-listening capability has distinctive advantages over TDMA, namely, you can better work around the obstructed building, mountain, rock, tree or problem by being able to be simultaneously served by multiple "listeners". Hence, the inherent advantages of CDMA vs. TDMA can really help with signal quality and reliability in a mobile satellite system. I believe the CDMA signal multi-path nature of Globalstar vs. the TDMA single-path nature of Iridium is a very fundamental design "quality differential" between the two systems. Hope this is illuminating/elucidating. Best regards, Geoff