A W-Band E-Plane Waveguide In-Phase Power Divider With Full Bandwidth and High Isolation

In this letter, a new two-way E-plane waveguide in-phase power divider (PD) with high port-port isolation operating in full W-band is proposed. This architecture is based on the classical six-port branch guide coupling principle, and consists of one input port, two output ports, and three isolation ports. To overcome the inherent tradeoff between fractional bandwidth and processing difficulty, a novel rectangular cavity coupling structure with greater waveguide width has been proposed. By analyzing, it is found that this novel layout allows broadband isolation and larger branch height which greatly eases the fabrication. Finally, an eight-branch prototype at W-band is designed, fabricated, and measured. In full W-band, the return loss is better than 20 dB and the isolation is better than 25 dB. The amplitude and phase imbalance between two output ports are less than ±0.4 dB and ±3.6°, respectively. The simulated and measured results are in good agreement.