基于H型缺陷地结构的超宽带带通滤波器设计

微波频段的宽带滤波器一般具有通带插入损耗大,带外抑制性差等问题,为了解决这个问题,采用具有慢波效应的缺陷地结构(DGS)和缺陷微带结构(DMS),设计了一种新型微波频段的超宽带滤波器。分别利用电磁仿真软件HFSS和平面印制板技术对其进行建模仿真和实物加工。实测与仿真结果良好吻合,带内插入损耗优于1.64dB,回波损耗优于13.93dB,通带范围在2.75~8.3GHz,实现相对带宽100.45%,高低阻带均抑制在-10dB以下,且该滤波器结构紧凑,体积小。

Design of a Ultra wideband Bandpass Filter Using H shaped DGS

Aiming at the problems of big passband insertion loss and poor out of band rejection of wideband filter operating at microwave band, a novel ultra wide band microwave filter with defected ground structure(DGS) and defected microstrip structure(DMS),which are of slow wave effect and single pole band reject characteristic,was designed in this paper. The modelling and simulation of the filter have been carried out by using the electromagnetic simulation software HFSS and the devices have been fabricated by the PCB process. The measured results agree well with the simulation ones. The proposed filter has an insertion loss of better than 1.64 dB and a return loss of better than 13.93 dB;a fractional bandwidth of 100.45% are achieved, the passband range is from 2.75 to 8.3 GHz; besides, the stopband attenuation is up to -10 dB. The filter shows a desired performance with a compact size.