Investigations of AMC and its applications for performance enhancement of planar antenna arrays

Artificial magnetic conductor structures (AMCs) is an effective approach to significantly improve the bandwidth and radiation gain of low-profile antennas. Comparing with other techniques, it needs no extra fabricated processes and takes the merit of easy integration. Three examples of AMC structure-based patch antennas are proposed and experimentally demonstrated. As a result, the 2×2 edge-fed patch antenna array using AMCs can achieve over 4 times bandwidth enhancement and about 3dB peak gain improvement than cavity backed antenna. Comparing with the conventional square AMCs, the patch antenna using the AMCs with inserted-stubs can achieve wider bandwidth and higher and more stable gain. Although low temperature co-fired ceramics (LTCC) substrate has a high permittivity, the relative bandwidth of the mmW LTCC antenna array using AMCs can reach 13.7%, which is about 5 times wider than that of ordinary antenna; meanwhile the peak gain can reach 13.3dBi, the stable gain (±1dB) and radiation pattern in the whole band of interest can be observed also.