Mutual coupling reduction of quasi-Yagi antenna array with hybrid wideband decoupling structure

Unlike conventional decoupling technologies that merely concern antenna characteristics in a limited range of frequency, this paper proposes a novel hybrid wideband structure to decouple ultra-wideband (UWB) quasi-Yagi antenna array. With the demand of achieving trade-off between mutual coupling and gain in the entire operating band, the evolution of the configuration is meticulously conducted by introducing multiple slots and their complementary counterpart, a rake-type locker, and an I-shaped isolator. Simulation and measurement results indicate that the decoupled array owns an increased impedance bandwidth (92.1%), reduced mutual coupling (lower than -20 dB), comparable gain and modified radiation patterns. The hybrid wideband decoupling structure reveals its potential application in planar wideband and multielement antenna arrays.