基于L型槽结构的小型化SIW滤波器

为了解决传统基片集成波导(SIW)滤波器在通信电路中占用空间较大的问题,提出一种新型的开槽方法实现了小型化SIW滤波器。通过在四分之一模基片集成波导(QMSIW)谐振腔的顶层金属板上蚀刻L 型谐振槽,利用开槽扰动的模移技术原理,使QMSIW 腔的谐振基模被移动到低频处。基于此,设计了一款中心频率为2.6 GHz,相对带宽为8.6%的二阶准椭圆响应带通滤波器,且在通带外的上下阻带给出了传输零点,提高了滤波器的选择性。实际测试的S参数与仿真结果吻合,表明蚀刻L型槽结构可以实现小型化和高选择性。

Miniaturized SIW Filter Based on L-Shaped Slot Structure

In order to solve the problem that the traditional substrate integrated waveguide (SIW) filter occupies a large space in the communication circuit, a new slotting method is proposed to realize the miniaturized SIW filter. The Lshaped resonant slot is etched on the top metal plate of the quarter-mode substrate integrated waveguide (QMSIW) resonant cavity, and the resonant fundamental mode of the QMSIW cavity is moved to the low frequency by using the mode shift technique of slotted disturbance. Based on this, a second-order quasi-elliptic response band-pass filter with a center frequency of 2.6 GHz and a relative bandwidth of 8.6% is designed, and gives transmission zeros in the upper and lower stopbands outside the passband, thus improving the selectivity of the filter. The actual measured S parameters are consistent with the simulation results, which show that etching L-slot can realize miniaturization and high selectivity.