A Single-Fed Microstrip Parasitic Array Antenna for Low-Cost Three-Dimensional Beam Steering

In this paper, the single-fed microstrip parasitic array antenna for low-cost three-dimensional beam steering in 5.8GHz ISM(5.725GHz?5.825GHz) band is designed and implemented. The antenna is comprised of one feed active element and four passive elements with variable reactance loads. The beam steering range of implemented antenna is achieved three-dimensional beam steering of ±28° at azimuth angle Φ=0°, Φ=45°, Φ =90°, and Φ=135° by adjusting variable reactance loads. The maximum gain of the antenna in the beam steering range have within 7.23dBi~9.36dBi and the bandwidth of return loss lower than ?10dB covers 5.8GHz ISM band regardless of the beam steering angles.