Novel and active technique for controlling the radiation pattern of the half-width microstrip leaky wave antenna array

Abstract

A novel, half width–microstrip leaky wave antenna (HW–MLWA) array is presented in this paper. It can electronically control its beam at fixed frequency using a double gap capacitor with diodes and has good impedance matching and very small variation gain while scanning. The control radiation pattern of leaky wave antennas (LWAs) is examined in steps at a certain frequency using binary switches, and a novel HW–MLWA array is proposed. This antenna is mainly composed of two elements of HW–MLWA and seven control unit cells (CUCs). In addition, a reconfigurable CUC is created by combining two triangle patches as double–gap capacitors with two diodes as a switch to connect the patches with a ground plane. The proposed antenna is fabricated and validated. To achieve certain–frequency beam steering, a patch in each CUCs is independently disconnected or connected with the ground plane by using PIN diode switches. When the state of the patch cell is changed, the reactance profile is altered at the free edge of the microstrip that caused the direction of the main beam to change. This proposed antenna prototype can scan the main beam between +22° to +63° at 4.2 GHz, and the antenna has a measured peak gain of 12.72 dBi at 4.2 GHz.