Analysis of CDMA for non-geostationary satellite systems .1. Forward service link in Rician fading channel with satellite diversity and power control

Analytical methods to analyze the forward service link from satellites to users of non-geostationary multi-beam satellite systems using direct-sequence spread-spectrum code-division multiple-access (DS-SS CDMA) techniques in a Rician fading channel with satellite diversity and power control are presented. Specifically, analytical expressions of the probability of the received ratio of bit-energy to noise-plus-interference density at the user's RAKE receiver output less than the required ratio are derived. The derived expressions are functions of the satellite constellation, user distribution, loading scenario for satellite antenna beams, spread-spectrum chip rate, information rate, traffic loading for each CDMA carrier, path loss, transmit power, transmit antenna patterns of the satellite antenna beams, receive antenna patterns of the users, Rician fading parameters, satellite diversity order, as well as power control scenario. Thus, this paper provides the analytical methods to determine system availability and capacity for the specified system parameters.