e for this part of the spectrum. This licence authorises positioning data , paging messages and voice communication to be sent via satellites. Iridium made variations on the way the satellites are to be launched. At one time, one dedicated space-craft was to be used, but now , to minimise risks , the satellites are being launched a few at a time by different launch vehicles such as the US Delta 2 , or the Russian Proton rocket . Furthermore Iridium shunted down the number of satellites from 77 to 66 , with each having a 48 channel capability instead of 37 . That means each satellite will be able to process more calls at the same time. They will be deployed in six different orbital planes with eleven satellites in each plane. Each satellite is triangular in shape , about 4.5 m long and 1 m across each base . (Fig 4 ).This shape allows for more than one satellite to be placed on a single launch vehicles . Including fuel the satellite weighs 690 kg and has an orbit of 780 Km above the earth's surface . The total cost of the Iridium project would be US $ 4,370 million.Fig 4 : An Iridium satellite GlobalstarThe Globalstar proposal is from Loral Qualcom Satellite Services Corporation, LQSS. Heavily backed by French interests, including Aerospaciale, Alcatel, and Alenia, LQSS will initially launch 24 satellites to initially provide an optimised service to continental USA. International operations will follow, after deployment of an additional 24 satellites . Each satellite should cover an area of 400 miles in diameter. Two kinds of user equipment have been proposed . The first, a vehicle mounted terminal based on a car radio design, will be easily removable and easy to operate. The second is a hand held terminal that the user can take anywhere. Each terminal has an average transmitting power less that 1 watt .Like Iridium, LQSS plans to provide transmission services to organisations which will resell capacity to other resellers . Globals...
