Differentially Proximity Coupled Ring Printed Antenna Array For L-Band SAR Application

Abstract

This paper presents the development of ring printed antenna array fed by differentially proximity coupled technique. The proposed antenna array is designed to operate at the center frequency of 1.275 GHz for L-band synthetic aperture radar (SAR) application. It is deployed on 2 layers of FR4 epoxy dielectric substrate with each layer thickness of 1.6mm. The antenna array consists of 5 circular ring shape elements on the top side of first layer dielectric substrate, while the microstrip line feeding network is on the top side of second layer. Some parametric studies are conducted to investigate the impact of varying physical parameters to its performance. The optimized antenna array which is implemented for realization has the dimension of 61.4mm × 173mm. The characterization result shows that the realized antenna array works properly at the desired frequency of 1.275GHz with the reflection coefficient (S11) value of –25.56dB and the –10dB impedance bandwidth of 30MHz. The measured –3dB beamwidth in E-plane is 103° and 52° for θ = 0° and ϕ =90°, respectively, while in H-plane for θ = 90° is 96°.