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据TELEPHONY 1990年6月刊报道:莫托罗拉公司(Motrola Inc.)宣布,它将发射一个新的卫星通信系统,从而建立世界上第一个全球蜂房式电话服务网络。 Motorola公司最初的计划是在距地面约600英里的低轨上建造一个由15至22颗卫星组成的网络,预计可于1993年第二季度投入使用。与高轨相比,卫星在低轨能消防电话通讯中的时延问题。如果各方面的需求得到保障的话,该公司最终将发射60至70颗卫星。最初的投资接近十亿美
According to TELEPHONY, June 1990, Motrola Inc. announced that it will launch a new satellite communications system to establish the world’s first global cellular telephone service network. Motorola initially planned to build a network of 15 to 22 satellites on a low-rise rail about 600 miles above the ground and is expected to be operational in the second quarter of 1993. Compared with the high-speed orbit, satellite delay in low-rail fire telephone communication problems. The company will eventually launch 60 to 70 satellites if all aspects of demand are guaranteed. The initial investment of nearly one billion US dollars