差分双频滤波天线设计

Design of Diffirential Dual-Fequency Filting-Antenna

本文设计了一个能够工作在WLAN频段的差分双频滤波天线,该差分双频滤波天线由差分双频滤波器和差分双频天线构成.通过在天线的馈线上插入滤波器,可以改善滤波天线阻抗带宽;通过在双频滤波器内部引入交叉耦合和内部反馈特性,可以有效提高滤波天线的选择性.仿真结果表明:该差分滤波天线可以工作在2.4GHz和5.8GHz频率范围内,两个通带的相对带宽达到17%和20%,并且在2.05GHz,4.75GHz和6.95GHz出现了3个辐射零点,两个通带内最大增益均达到了3.3dBi.

In this paper, a differential dual-frequency filtering-antenna is designed for WLAN band. The differential dual-frequency filtering-antenna is consist of a differential dual-frequency filter and a dif- ferential dual-frequency antenna. By embedding a filter inside feeding line of antenna, the impedance bandwidth can be improved for the differential dual-frequency filtering-antenna. And by adopting the cross coupled and self-feedback structure, the good selectivity at the pass band edge can be achieved. The simulation results show that the proposed differential dual-frequency filtering-antenna can work at center frequencies of 2.4 GHz and 5.8 GHz, with the fractional bandwidth band 17% and 20%, respec- tively. Three radiation zeros appear at 2.05 GHz, 4. 75GHz and 6.95 GHz. Moreover, the 3.3 dBi peak gain can be obtained over two operating bands.