High Gain, Wideband Aperture Coupled Microstrip Antenna Design Based on Gain-Bandwidth Product Analysis

Aperture coupled antennas are studied in terms of Gain-Bandwidth Product (GBWP). To understand whether resonant or non-resonant slot coupled antenna has better performance, several antenna designs with different slot shapes are optimized and compared to each other. Even for a pin-feed microstrip antenna, we show that there exists a substrate height and aspect ratio for optimal GBWP. Based on this analysis, a stacked aperture coupled antenna is designed and optimized for high gain and wideband for Ku band downlink (10.8- 12.75 GHz) applications. The designed antenna exhibits 9.5 dBi broadside gain with 80° half power beam width and almost 30% bandwidth. Ku-band gain ripple is less than 0.5 dB. The antenna is built and measured. Several figure-of-merits based on GBWP have been defined to compare its performance with earlier works. Proposed antenna can be used in demanding high gain, wideband, beam scanning array applications.