Microstrip fed single-layered substrate aperture coupled microstrip antenna

A novel aperture coupled microstrip antenna is proposed. This structure uses a single substrate for achieving a low profile, good radiation efficiency and reduced back radiation. In the proposed design, a pair of radiating patches and a microstrip feed line are both etched on the top of a microwave substrate, and twin slots are etched on the bottom of this substrate. Simulated and measured radiation patterns indicate that the proposed structure can achieve high radiation efficiency, 25dB front-to-back radiation ratio, and 30dB cross-polarisation field level below the corresponding co-polarisation field level. Such antenna architecture is important for mobile communication systems, where low profile, compact size and high radiation efficiency are required.