A single-substrate microstrip-fed slot antenna array with reduced back radiation

A novel design for a microstrip-fed slot antenna array is proposed and developed for reducing back radiation. The proposed design is based on a new aperture coupling technique in which two parallel slots are fed by a microstrip line and coupled to two pairs of microstrip patch radiators etched on the opposed side of the slots. In contrast with most slot and microstrip patch combinations, the patches are employed to reduce radiation into the half-space that they occupy. By adjusting the suitable structure parameters, the back radiation of the slots is significantly reduced. Design considerations for the structure are given, and the design is validated by measurements.