X-Band Cavity-Backed Stacked Rectangular Microstrip Antenna for Super-Wideband and High Isolation

A rectangular one bottom four top (1B4T) stacked antenna has been proposed in X-band. The antenna has superwideband, high gain and high isolation. The two cavity walls have been used to improve the bandwidth (BW) and gain performance of the antenna. The antenna has been designed with air substrate for broad BW and high efficiency. The antenna designed at the center frequency of 10.3 GHz is yielding a BW of 72% (6.59-14.01 GHz) for |S
11
| ≤ –10 dB and a minimum isolation of 36 dB between two such antennas. The results show that it has a maximum gain of 12.62 dBi, with an average gain of 11 dBi over the entire impedance BW. The radiation efficiency is above 97% throughout the super-wide BW. The achieved features make the proposed antenna a good candidate for FMCW radars and military applications.