SAW FILTER MATRIX FOR SS/FDMA SYSTEM

The configuration and function of a surface acoustic wave (SAW) filter matrix used on board a satellite to implement a subchannel switched FDMA (SS/FDMA) system is described. The function and configuration of the SAW filter matrix (SFM) are described. Conditions imposed on the amplitude and phase of two adjacent subchannels to provide a broad channel by combining the outputs of the subchannels are investigated. Electrical and transmission characteristics of an SAW filter matrix used in four-beam SS/FDMA system with a subchannel-combining function are presented, demonstrating its technical feasibility. When implementing an SFM, it is important that the devices used for a satellite-based SS/FDMA router are sufficiently reliable for the design life of the satellite. A methodology is shown that gives a redundant configuration with the lightest mass and that achieves the targeted reliability. Example calculations for a four-beam SS/FDMA router are given.