基于LTCC技术的电磁混合耦合宽阻带滤波器设计

Design of Wide Stopband Filter with Electric and Magnetic Mixed Coupling Based on LTCC Technology

针对复杂电磁干扰,采用电磁耦合相消产生传输零点的原理,提出一种基于电磁耦合相消的宽阻带滤波器。对电路谐振单元进行奇偶模分析,在ADS软件中设计电路,然后在HFSS软件中对该电路进行三维仿真优化,最后采用LTCC材料进行生产。该器件采用左右对称结构,以降低设计复杂度和元件体积;利用电磁耦合相消原理确定零点位置,调整谐振间距实现零点控制;加入源负载耦合,以实现第4个传输零点,增强选择性和阻带宽度。最终设计的宽阻带滤波器物理尺寸为3.2 mm×1.6 mm×0.89 mm,实物测试结果表明该器件阻带范围广且通带具有高陡峭性。

Aiming at the complex electromagnetic interference,this paper adopts the principle of transmission zero point produced by electromagnetic coupling cancellation,and proposes a wide-band rejection filter based on electromagnetic coupling cancellation.The odd-even mode analysis is performed on the circuit resonant unit,the circuit is designed by the ADS software,and then the circuit is optimized by three-dimensional simulation with the HFSS software,and finally it is manufacuured by LTCC material.The device adopts left and right symmetrical structure to reduce design complexity and component volume;determines the zero position by electromagnetic coupling cancellation principle;adjusts the resonance spacing to achieve zero point control;adds source load coupling to achieve the fourth transmission zero point,enhances selectivity and the stop band width.The final wide stop-band filter is designed with a physical size of 3.2 mm×1.6 mm×0.89 mm.The physical test results show that the device has a wide stop band and a high steepness in the pass band.