A Q-Band dual-mode cavity-backed wideband patch antenna with independently controllable resonances

In this paper, a dual-mode cavity-backed patch antenna and a 2×2 array is proposed for Q-band wireless applications. In addition to the original TM01 mode of patch antenna, an independently controllable resonance is introduced by loading the antenna with an inductive via and an annular slot. The bandwidth (return loss<;-10 dB) of the antenna element is thus expanded to 12.4% while the bandwidth of the 2×2 array is 12.7%, with a peak gain of 6.57 dBi and 10.6 dBi, respectively. The 2-dB gain bandwidth of the array is wider than 13.95%. Besides, in order to provide a deep understanding of the antenna, a fully physically based circuit model is presented. The circuit simulation and full wave simulation agree well with the measurements.