Fully Reconfigurable Manifold Multiplexer

In this paper, a fully reconfigurable three channel manifold-coupled output multiplexer is presented. The multiplexer is based on frequency and bandwidth reconfigurable four-pole filters with two transmission zeros. The filters employ nonresonating cavities to achieve tunability of couplings. A novel manifold reconfiguration concept has been developed, allowing frequency and bandwidth tuning for filters connected to the manifold. This is achieved by adding tunable reactive elements along the manifold. These reactive elements allow the phase relationships between the channels to be adapted. This concept has been demonstrated on a three-channel multiplexer operating at ka-band frequencies (in satellite communication ka-band denotes the 17.7-21.2-GHz band for downlink). It allows contiguous as well as noncontiguous frequency plans. The multiplexer band could be tuned to a frequency range of 500 MHz (19.9-20.4 GHz), and the bandwidth for the individual filters could be tuned from 36 to 72 MHz. Even swapping the center frequencies of two filters on the manifold is possible.