一种结构紧凑的可抑制超宽带谐波的滤波天线

A Compact Filtering Antenna With Ultra⁃Wideband Harmonic Suppression

采用口径耦合馈电的方式设计了一种结构紧凑的可抑制超宽带谐波的滤波天线,为了提高近通带的选择性,在方形辐射贴片两侧放置带有容性负载的矩形寄生贴片,并在接地板上刻蚀开口矩形环,分别在上下边带各引入一个辐射零点。为实现超宽带谐波抑制,在馈线上加载平面耦合滤波结构,在4~18 GHz频段产生宽阻带,在接地板上刻蚀H形缝隙并减小接地板尺寸,进一步拓宽阻带带宽。天线的整体尺寸为40 mm×35 mm×2.4 mm。天线的工作频带为3.35~3.6 GHz,相对带宽为7.1%,在上下边带的滚降度分别为94 dB/GHz和54 dB/GHz,在4~23.48 GHz(6.7 f_(0),f_(0)为天线的中心频率)间的反射系数均大于−3 dB。

A compact filtering antenna with ultra-wideband harmonic suppression is proposed,using the aperture-coupled feeding.In order to improve the selectivity of the passband edge,the rectangular parasitic patch with capacitive loading is placed on both sides of the square radiation patch,the split rectangular loop is etched on the ground,and two nulls are beside the passband.In order to achieve an ultrawideband harm suppression,a planar coupling structure is loaded on the feedline to generate a wide stopband from 4~18 GHz,an H-shaped slot etched on the size-reduced ground forms defected ground structure(DGS)to enhance the suppression bandwidth.The antenna has an overall size of 40 mm×35 mm×2.4 mm.The impedance bandwidth of the antenna is 3.35~3.6 GHz(7.1%).The upper and lower selectivity is 94 dB/GHz and 54 dB/GHz,respectively.The reflection coefficient of the antenna is greater than−3 dB in 4~23.48 GHz(6.7 f_(0),f_(0) is the center frequency)