基于异向传输线的亚波长谐振腔设计

Design of left-hand transmission line based subwavelength cavity resonators

提出了一种新型的谐振腔,该谐振腔的谐振条件与普通谐振腔不同,其两个端面的总相移不必是180°的正整数倍。这种谐振腔由异向传输线和右手传输线两种不同性质的传输线级联构成,它利用耦合腔链作为异向传输线实现负相移,同轴波导作为右手传输线实现正相移,使谐振腔两个端面的总相移为零,满足谐振腔的谐振条件。由于它与传统谐振腔谐振条件不同,理论证明这种谐振腔的长度可远远小于传统谐振腔,设计实例的仿真结果表明这种新型谐振腔的长度最短仅为传统谐振腔的1/7。

Resonant condition of this new cavity resonator is different from that of the traditional cavity resonators for its total phase shift need not be a positive integral multiple of 180°. The left-handed transmission line（LHTL） which can realize a negative phase shift is a resonant-slot coupled cavity chain, while the right-handed transmission line（RHTL） which realizes a positive phase shift is a coaxial waveguide, and resonant condition can be satisfied as long as the total phase shift keep zero. Because of its larruping resonant condition, the theory and simulation prove the length of the cavity resonators can be much smaller than that of the traditional cavity resonator.