Low Sidelobe X Band Patch Antenna Array Design with High Isolation

Abstract

Several factors that influence radar performance are the side lobe level, front to back ratio, polarization, and main beam width, which are caused by the antennas utilized. The isolation between the transmit and receive antennas is crucial for FMCW radars. The highest transmit power is constrained by isolation, which also directly impacts the sensitivity of the radar receiver. In the past, electromagnetic bandgap ( [1 ]], air gap[2], and baffle construction [ were used to obtain high isolation levels. However, the EBG and air gap considerably increased the antenna's size, and the solid metallic baffle design was bulky and had a narrowband effect. The aim of this study is to design a wideband FMCW radar antenna with greater than 70 dB isolation between TX and RX antennas with a low sidelobe ( 20 dB) in both azimuth and elevation planes.