High-performance microwave hardware is used in a wide spectrum of communications systems, in particular, communication satellites, earth stations, wireless base stations, and other point-to-point repeaters.The demand for such high-performance devices originated from the extraordinary price operators paid to acquire the spectrum rights and also the high cost of sending a communication satellite into orbit.The history of high performance devices for wireless base stations and satellite payloads extends back many years with the invention of high selectivity filters, contiguous multiplexers and butler matrices.As a result, system architectures have evolved to the characteristics specific to these advances with ever increasing number of channels to gain flexibilities.The need for high perfor