基于双模环形谐振器的双频带滤波器设计

Design of the dual frequency band filter based on dual mode ring resonator

为实现无线通信领域对滤波器的小型化要求,基于微带平面结构易于集成的特点,设计了一款应用于无线局域网(WLAN)的双频带微波滤波器,其中心频率为2.4/5.2 GHz.首先,利用矩形环形微带谐振器自身存在的两个模态相互耦合形成通带,以缩小滤波器体积,并且在通带两边各形成一个零点,以提高滤波器的选择性.然后,对矩形环形谐振器进行压缩,以进一步缩小滤波器体积.最后,采用IE3D仿真软件对所设计滤波器的性能进行仿真测试.实验结果显示:在2.4/5.2 GHz时,滤波器通带内的插入损耗分别为-3.0 dB和-2.5 dB,回波损耗均小于-15 dB,且整个电路尺寸为18 mm×18 mm.这表明,该方案设计的滤波器达到了性能指标,且实现了小型化.

Aiming at the requirement of miniaturization of filter in wireless communication field,based on the characteristics of easy integration of microstrip plane structure,a dual-frequency microstrip filter with central frequency of 2.4/5.2 GHz for Wireless Local Area Network(WLAN)is designed.Firstly,two modes of the rectangular ring microstrip resonator are coupled each other to form the passband to reduce the volume of the filter,and two zeros are formed on both sides of the passband to improve the selectivity of the filter.Then,the rectangular ring resonator is compressed to further reduce the filter size.IE3 D simulation software is used to simulate the performance of the designed filter.The test results show that the insertion loss in 2.4/5.2 GHz is-3.0 dB and-2.5 dB respectively,and the return loss is less than-15 dB,and the overall circuit size is 18 mm×18 mm.The experimental results show that the filter proposed in this paper can meet the requirements of performance indicators,and the structure can realize the miniaturization.