A Wideband Differential-Fed Microstrip Patch Antenna Based on Quad-Mode Resonance With Radiation Patterns Correction

A wideband differential-fed microstrip patch antenna (DMPA) based on quad-mode resonance with radiation patterns correction is proposed in this communication. First, the common problems presented in multi-mode resonant microstrip patch antenna (MPA) are introduced: it is difficult for the numbers of operation modes to exceed two, and there are radiation nulls emerged in the broadside. Second, the physical structure and mode combination process of the DMPA are demonstrated in detail. Third, through the equivalent magnetic current array model, we comprehensively introduce the principles and processes of radiation patterns correction. Finally, a prototype is fabricated and measured. The measuring results are consisted with simulation ones. The proposed DMPA achieves 29.4% (3.22–4.33 GHz) impedance bandwidth at the profile of $0.058\lambda $ (center frequency wavelength), and it has a stable gain in broadside without radiation nulls.