A simple method for loading analysis of SATCOM system with heterogeneous gain states

The Wideband Global SATCOM (WGS) system is being developed to provide the ability of flexible band-switching in satellite, so-called “any coverage to any coverage”. With the digital channelizer transponder used in, the transponder power gain of individual links could be adjusted respectively. Heterogeneous gain states can be especially useful for balancing the needs of dissimilar links in the same transponder. This paper presents a simple optimum method which considers the effect of HPA nonlinear for deriving these individual channels gain to minimize the amount of transponder power utilized. As seen from the theory analysis the optimal terminal transmit powers are the allowable EIRP and the optimal gains for each-channels obtained by directly solves a set of simple nonlinear equations which does not use any search algorithms or matrix inversion. Take into account the power utility, the new algorithm also search the optimum transponder's operating point for obtain the maximum power utilization. A practical example in computing the optimum gains and transponder power utility is also presented.