Substrate-Integrated-Waveguide Diplexer Filter for SATCOM-on-the-Move

Satellite communication (SATCOM) on-the-move applications require low-cost compact antenna arrays to enable mobile users to track the satellites. Full-duplex operation requires efficient diplexers that satisfy stringent requirements in a compact footprint to enable tight integration within the antenna system. In this contribution, substrate-integrated-waveguide technology is leveraged to design a single-layer third-order diplexer filter based on a dual-mode cavity. Simulations and measurements demonstrate that the diplexer enables full-duplex operation for Ku-band SATCOM on-the-move systems, effectively separating the [11.7-12.75] GHz downlink (Rx) band from the [13.75-14.50] GHz uplink (Tx) band, yielding an isolation larger than 20 dB and an insertion loss below 3.7 dB over a fractional bandwidth (FBW) of 8.6% in Rx and 5.3% in Tx.