Analysis of the microstrip-grid array antenna and proposal of a new high-gain, low-complexity and planar long-range WiFi antenna

This study presents a systematic numerical analysis of the microstrip-grid antenna aiming not only to explore the antenna performance limits in terms of frequency impedance bandwidth and maximum gain, but also to use this analysis as a starting point for further optimisation. The obtained antenna has dimensions 297mm x 210mm x 9.9mm and at 2.41 GHz, has a maximum gain of 15.4 dB, which is very close to the directivity of an ideal, lossless aperture antenna with the same dimensions, at the same frequency. Measurements have shown that the antenna operates from 2.38 to 2.51 GHz (i.e. across the WiFi-band with a 5.32% frequency bandwidth relative to 50 Omega), with maximum radiation efficiency 98.2%, while the latter remains over than 91% for the whole WiFi-band, and finally has a measured half-power beamwidth of 18.5 and 34.5 degrees in the horizontal and vertical planes, respectively. Thus, the antenna is suitable candidate for long-range WiFi links.