A wideband broad-wall directional coupler is designed using the ridge-gap-waveguide (RGW) technology operating on the quasi-TEM mode. Large coupling apertures are used between two mirrored RGWs. Several coupling levels are achieved according to the number of apertures used and the ridge height in the two RGWs. Furthermore, a design procedure to obtain the desired coupling levels is introduced. Simulations and measurements show that tight-to-loose coupling levels (3–33 dB) can be achieved with the same coupler configuration, but with different parameters within ±1-dB coupling variations. The couplers achieve better than 15-dB return loss and better than 20-dB isolation within a 40% bandwidth with ±1 dB and ±2 degrees of magnitude and phase errors, respectively.

中文翻译：

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宽带脊隙波导紧松耦合器的分析与设计

使用在准 TEM 模式下运行的脊隙波导 (RGW) 技术设计了宽带宽壁定向耦合器。两个镜像 RGW 之间使用大耦合孔径。根据使用的孔径数量和两个 RGW 中的脊线高度，可以实现多个耦合级别。此外，还介绍了获得所需耦合水平的设计程序。仿真和测量表明，可以使用相同的耦合器配置实现紧密到松散的耦合电平 (3–33 dB)，但在 ±1-dB 耦合变化范围内具有不同的参数。这些耦合器在 40% 的带宽内实现了优于 15dB 的回波损耗和优于 20dB 的隔离度，幅度和相位误差分别为 ±1dB 和 ±2 度。