基于等效电路模型的基片集成波导滤波器快速设计方法

A fast design method of substrate integrated waveguide filter based on equivalent circuit model

提出了一种基片集成波导滤波器(SIW)的快速设计方法,减少全波仿真的优化次数,缩短设计时间。建立了SIW滤波器的等效电路模型,采用LC并联谐振器代表SIW谐振腔,采用移相器代表耦合窗口。通过电路级仿真优化使得等效电路模型的响应与SIW滤波器全波仿真结果一致,从而获取SIW滤波器各个谐振腔的谐振频率、各个耦合窗的耦合系数,并与目标值相比对进而得知SIW滤波器各个尺寸参数的优化方向。为验证该方法的有效性,设计了一款中心频率为21 GHz、带宽为1 GHz的6阶SIW滤波器。设计过程只需6次全波仿真即可得到较为理想的滤波器结果。

A fast design method of substrate integrated waveguide(SIW)filters is proposed to reduce the optimization times of the full-wave simulation and the design time.The equivalent circuit model of the SIW filter is established,with the resonant cavity represented by LC parallel resonators,and the coupling iris by phase shifters.The resonant frequencies and coupling coefficients of the SIW filter are obtained through the circuit-level simulation and optimization,which make the frequency response of the equivalent circuit model coincide with one of the full-wave simulation results.Compared with the desired values,the optimization direction of the SIW filter in dimensions and parameters is acquired.A six-order SIW filter is designed,with the center frequency of 21 GHz,and the bandwidth of 1 GHz,to verify the effectiveness of the method.A filter with good performance can be obtained only through 6 full-wave simulations.