DESIGN AND OPTIMIZATION OF DUALBAND YAGI-UDA ANTENNA FOR WIRELESS COMMUNICATIONS

摘要

A novel branch structure is proposed and optimized to design a Yagi-Uda antenna with dual-band (915-935 MHz and 1760-1805 MHz) performance. In the design, some parametric studies and computational experiments are made to investigate the variation of performance with some of the key parameters. The proposed antenna is optimized by using multiobjective differential evolution algorithm to obtain required performances of voltage standing wave ratio (VSWR), gain and front-to-back ratio (FBR) in the two bands. Prototype with optimal dimension is manufactured and measured, and the results are in good agreement with the simulated ones. In the two operating bands, the proposed antenna achieves directional radiation and the performances that VSWR < 2, gain 4.9-7.6 dBi and FBR 9.8-17.3 dB, making it suitable for the nonfixed base station backhaul in wireless communications.