A Small Ultra-Wideband Unidirectional Microstrip Antenna for Through-Wall Radar Application

Abstract

A portable through-wall radar needs a small size broadband antenna with a unidirectional radiation pattern. The antenna that meets these requirements is microstrip antenna. This paper explains an Ultra-Wideband (UWB) microstrip antenna that has been designed and manufactured for through-wall radar application. The design and simulation of the antenna were carried out with 3D electromagnetic simulator. The substrate material of the antenna was FR-4 with a dielectric constant of 4.3 and a thickness of 1.6 mm. The simulation results showed that the antenna had a 4.8 GHz of bandwidth ranging from 4.2 to 9 GHz, with a return loss less than -10 dB. The antenna dimension using FR-4 substrate is smaller than using Duroid 5880 with a dielectric constant 2.2. Additionally, the measurement results showed that the antenna had a 5 GHz of bandwidth ranging from 3.8 to 8.8 GHz, with a return loss less than -10 dB.