Multiple-port SIW power divider utilizing cascade-connected crisscross directional couplers

This paper presents a compact multiple-port power divider with a Substrate Integrated Waveguide (SIW) structure. The proposed divider consists of several cascaded-connected directional couplers inserted a number of metallic posts within the SIW with suitable coupling coefficients and a right-angled corner, and realizes an equal power division in a same direction by using honeycomb structures which consist of a large number of small-size holes vertically installed between the directional couplers as phase shifters. By optimizing the circuit dimensions of directional couplers and the right-angle corner at a operating frequency of 17GHz based on the H-plane planar circuit approach [1], a good performance of an equal power division within ±0.3dB unbalance and 20dB return loss can be obtained with a relative bandwidth of about 2%. The 5-way SIW power divider which the circuit patter is decided by electromagnetic simulations is fabricated on a dielectric substrate to verify the design procedure. Measurement results of the fabricated divider are nearly agreement with the simulation results.