A vertically integrable, ridge-waveguide-based power divider topology for achieving arbitrary split ratios is presented, along with its detailed design procedure. The divider’s ridge-waveguide cross-section enables a compact design with minimal transmission loss, while its vertical topology supports modular deployment within multi-stage feed networks for antenna arrays. The proposed method achieves power split ratios between 0.05 (1:20) and 1 (1:1) using a co-design strategy of a dogbone aperture and a modified ridge geometry. By separating the power divider behavior into two distinct regimes, precise control of the split ratio is achieved while the design space remains compact, requiring no more than four geometrical parameters. Design rules are formulated accordingly, relating the targeted split ratio to each of the relevant parameters. To validate the design methodology, five power dividers were fabricated for the fifth-generation (5G) n257 frequency band between 26.5GHz and 29.5GHz, with representative split ratios of 0.05, 0.25, 0.5, 0.9 and 1. Their average measured split ratios equal 0.05, 0.24, 0.51, 0.91 and 0.99, while all are matched consistently with their reflection coefficient below -10dB within the n257 band, thereby confirming the effectiveness of the proposed design procedure.
