The paper reports on the design of coupled-line trans-directional (CL-TRD) coupler with independent or simultaneous tuned frequency, coupling coefficient and phase difference (PD). Based on the proposed structure, four kinds of couplers are exhibited, including a phase-tuned coupler with arbitrary frequency and coupling, a frequency-tuned coupler with arbitrary coupling and non-standard phase, a coupling-tuned coupler with arbitrary frequency and non-standard phase, a simultaneous frequency-, coupling- and phase-tuned coupler. In the section of theoretical analysis, rigorous closed-form design equations are derived using the even-odd mode analysis. For verification, four prototypes are designed, fabricated and measured. Three of them are couplers with independent frequency, coupling or phase tuned. The designed 3-dB frequency-tuned coupler exhibits a frequency tuning range of 58.8% with a PD of 60°. The coupling-tuned coupler shows a tuning range of 3–15 dB with a PD of 70°. The designed phase-tuned CL-TRD coupler can provide a PD from 45° to 135°. Finally, a coupler with simultaneously frequency-, coupling- and phase-tunable was implemented. It has a wide frequency tuning range from 1.2 GHz to 2 GHz with a tunable coupling from 3 dB to 15 dB, and a tunable PD from 45° to 135°.

本文报告了具有独立或同时调谐频率，耦合系数和相位差（PD）的耦合线横向（CL-TRD）耦合器的设计。根据所提出的结构，展示了四种耦合器，包括具有任意频率和耦合的相位调谐耦合器，具有任意耦合和非标准相位的频率调谐耦合器，具有任意频率和非频率耦合耦合的耦合器。标准相位，同时进行频率，耦合和相位调谐的耦合器。在理论分析部分，使用奇偶模分析得出严格的闭式设计方程。为了验证，设计，制造和测量了四个原型。其中三个是具有独立频率，耦合或相位调谐的耦合器。设计的3 dB频率调谐耦合器的频率调谐范围为58.8％，PD为60°。耦合调谐的耦合器显示3-15 dB的调谐范围，PD为70°。设计的相位调谐CL-TRD耦合器可提供45°至135°的PD。最终，实现了同时具有频率，耦合和相位可调性的耦合器。它具有1.2 GHz至2 GHz的宽频率调谐范围，可调耦合范围为3 dB至15 dB，PD可调范围为45°至135°。