Excitation of parallel plate waveguide by an array of ridge waveguide T-junction

A broadband excitation of parallel plate waveguide fed by an array of ridge waveguide T-junction is proposed in this paper. This excitation is one of attractive candidates for high efficiency and mass producible planar array antenna in millimeter-wave applications. Since the proposed structure consists of feed circuit and parallel plate waveguide is compact in terms of size and arranged on the same layer as the parallel plate waveguide, it could be processed readily. The simulations show that the bandwidth is about 25.8% in terms of reflection less than -15dB with an amplitude fluctuate less than 2dB in parallel plate waveguide.