Integrated Multiport Leaky-Wave Antenna Multiplexer/Demultiplexer System for Millimeter-Wave Communication

A novel application of leaky-wave antennas (LWAs) as multiplexers/demultiplexers is proposed and experimentally demonstrated in the millimeter-waveband at 60 GHz. The first application is demultiplexing of an oblique-incident free-space wideband plane wave into 2N channels using N LWAs with different beam-scanning laws. The second application is N-channel multiplexing and demultiplexing using N pairs of identical LWAs in each other's far-field, where each LWA pair is designed such that the broadside frequency is the center frequency of its respective channel. The Friis transmission equation is first used to analytically demonstrate the two applications. The LWAs are then implemented using reflection-canceling slot pairs using substrate integrated waveguide technology. The two applications are demonstrated in full-wave simulations and experimentally by conducting horn-to-LWA and LWA-to-LWA transmission measurements. The proposed LWAs provide a simple, compact, and high-efficiency multiplexing/demultiplexing solution with high-integration capability with other circuitry. Compared with conventional multiplexers, LWAs do not require matching networks and can be directly scaled to higher frequencies using the same architecture.