Filtering Antenna for Satellite Communication Applications

Evanescent mode open-ended waveguides (OEWs) are ideally suited for satellite communications as they offer low-loss and high power handling capability in a compact footprint. As the dimensions of aperture are less than half-wavelength, the OEW can prevent grating lobes in phased-array applications. However, small aperture reflects the wave in the OEW, leading to inefficient radiation [1] . The antennas are conventionally connected to filters for rejection of out-of-band noise and for channelizing purposes. However, the classical methodology of independently designing filters/ antennas and connecting them through a transmission line not only increases the system loss, but also its size. Recently, ridge-waveguides [2] have been used to obtain simultaneous efficient radiation and filtering capabilities from an evanescent mode OEW.