一种宽带高方向性微带定向耦合器

A Broadband High Directional Microstrip Directional Coupler

文中设计了一种小型化的具有高方向性的多节微带线定向耦合器。通过将耦合微带线分段处理,得到由一节1/4波长段和两节1/8波长段组合的多段耦合器。非均匀介质微带耦合线中奇偶模相速度的差异导致微带定向耦合器的方向性较差。文中通过在耦合器馈线拐角处采用1/4圆弧提高了方向性。通过优化仿真设计实现了10 GHz耦合器,耦合度为25 dB,并且从6~14 GHz的方向性优于30 dB。与传统的并联耦合线耦合器相比,文中所提出的耦合器具有更小尺寸和更加出色的方向性,且实测和模拟仿真基本一致。

In this paper,a miniaturized directional multisegment microstrip directional coupler with high directivity is designed.By segmenting the coupled microstrip lines,a multisegment coupler composed of a quarter wavelength segment and two 1/8 wavelength segments is obtained.In addition,the difference of odd-even mode speed in the microstrip coupling line of non-uniform medium always leads to poor directivity of the microstrip directional coupler.Aiming at this problem,a quarter arc is adopted at the corner of the feed line of the coupler to improve directivity.A 10 GHz coupler is designed and implemented through optimized simulation.The coupling degree is 25 dB,and the directivity from 6 to 14 GHz is better than 30 dB.Compared with the traditional parallel coupled line coupler,the proposed coupler has smaller size has better directivity,and the measured and simulated results are basically consistent.