A 60-GHz Out-of-Phase Power Divider with WR-15 Standard Interface Based on Trapped Printed Gap Waveguide Technology

Recent developments in communication networks are catering to dynamic requirements as well as providing facilities for future potential applications that are significantly expanded. This necessitates the emergence of mm-wave components that exhibit desirable electrical characteristics, such as compactness, cost efficiency, and minimal manufacturing complexity. Gap waveguide (GW) technology is being considered a potential solution since it provides a promising guiding structure for millimetre-wave applications. This paper presents a novel out-of-phase power divider using the standard waveguide WR-15 interface. The presented power divider is based on a trapped printed gap waveguide (TPGW), which is designed to employ aperture coupling to achieve a stable \(180^{\circ }\) ${180}^{\circ }$ phase imbalance. The power divider and transition have been designed and optimised to minimise the reflection coefficient at the input WR-15 port within the desired frequency range of 50-65 GHz. A deep matching level of beyond \(-\) $-$ 20 dB is sufficient to obtain a relative bandwidth of 29% at 60 GHz. A back-to-back model is developed to validate the performance of the proposed power divider configuration and a standard WR-15 waveguide. Furthermore, mathematical analyses are performed to investigate the relationship between the back-to-back model and the individual power divider. A prototype for the proposed power divider through a back-to-back structure is fabricated to validate its performance, and good agreement is achieved between the simulated and measured results.