Power control error in a CDMA satellite communication system

An adaptive power control (APC) scheme is essential to overcome shadowing and distance losses in a land mobile satellite system. Such a scheme, implemented on the uplink, ensures that all users' signals arrive at the base station with equal average power as they move within the satellite spot beam-an important requirement in a CDMA system. Because of the lengthy round-trip delay on a satellite link, closed-loop power control systems are only of marginal benefit. Monk et al (1994) proposed an open-loop APC scheme to counteract the effects of large scale losses. A model was developed to characterize the performance of the APC. In this paper, we use the model to derive the overall system performance of shadowed users on the uplink of a coherent, asynchronous, coded CDMA system, on a land mobile satellite link.<
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