Gain Enhancement and Sidelobe Level Reduction of Microstrip Patch Antenna under Operation of TM50-Like Mode

In this paper, we propose a microstrip patch antenna (MPA) operating in the TM50-like mode, designed for gain enhanced and sidelobe levels (SLLs) reduction. Our methodology involves altering the resonator's surface current distribution by introducing three groups of transverse slots at points of null electric field. Additionally, two symmetrically positioned stubs are utilized to the antenna's gain enhanced. We verify that proper combinations of such artifacts on the proposed radiators significantly reduce the SLL while maintaining the high-gain characteristics of the TM50-like mode. A prototype was fabricated and characterized for operation around 7.6 GHz, in the C band. The results demonstrate that a realized gain of 15.0 dBi can be achieved, with the SLL reduced to approximately 15 dB, representing an excellent option for high-gain applications requiring a low profile and compact size.