Uniform microstrip array antenna with low sidelobe level for coastal surveillance radar application at 9.37–9.43 GHz

Abstract

Coastal Suveillance Radar (CSR) is crucial for coastal navigation. A microstrip rectangular patch with slotted inset-line antenna is proposed in this paper. The antenna operates at the frequency 9.37–9.43 GHz with VSWR below 1.3 and printed on Epoxy FR-4 substrate of dielectric constant of 4.6. The antenna array is also simulated on CST using uniform microstip array configuration consisting of 6×120 elements to yield the specification of horizontal beamwidth ≤ 1°, vertical beamwidth ≤ 20°, gain ≥30dB and sidelobe level ≤ −27dB. The simulation result of the array antenna has a horizontal beamwidth of 0.4°, vertical beamwidth of 14.2°, gain of 30.8dB, and sidelobe level of −27.5dB. Hence the proposed array antenna configuration is suitable for CSR application.