A novel wideband slot loaded microstrip patch antenna through reallocation of TM 1,0 , modified TM 0,2 and TM 1,2 modes

Abstract This paper presents a novel wideband microstrip patch antenna (MPA) characterised by a straightforward structure and operational efficacy across four resonances. The antenna consists of a truncated square patch, a coplanar capacitive feed and a slot on the patch. The square radiating patch is strategically truncated at its four corners to perturb the electric field distribution characteristic of the TM 0,2 mode, thereby facilitating the generation of a unidirectional far‐field pattern. Extensive analysis has elucidated the mechanism through which corner truncation diminishes the electric field peak associated with the TM 0,2 mode at the centre, resulting in the transformation of the dual‐beam pattern into a distinct single beam pattern. In addition, unlike conventional approaches that require additional components such as shorting pins, this approach reallocates three radiative modes—specifically TM 1,0 , TM 0,2 , and TM 1,2 —resulting in a simplified structure. Finally, a coplanar capacitive feed and a slot are employed to boost the input impedance frequency bandwidth and generate the fourth resonance, respectively. Therefore, four adjacent resonances are simultaneously excited by this method and a wide frequency bandwidth of approximately 80% with stable unidirectional radiation pattern and same polarisation are fulfilled. A prototype of the antenna is fabricated and measured to validate the design procedure.