2-Bit reconfigurable microstrip antenna with independently controlled hybrid slots for polarization and frequency switching

A 2-bit reconfigurable microstrip antenna capable of selectively switching its operating frequency and polarization is presented. The design features a novel dual-embedded, crossed-slot topology where slots on the radiating patch and the ground plane are controlled independently by two p-i-n diodes. This 2-bit control scheme facilitates four distinct operational states. When the diodes are in identical states (ON/ON or OFF/OFF), the antenna exhibits linear polarization at two discrete resonant frequencies, 2.51 GHz and 2.44 GHz. When the diodes are in opposing states (ON/OFF or OFF/ON), the antenna radiates with left-handed (LHCP) or right-handed circular polarization (RHCP) at 2.45 GHz. A prototype was fabricated and measured, with results showing excellent correlation with simulations. This compact, single-layer design demonstrates a versatile and efficient solution with high functional density for modern wireless systems requiring agile beam control.