Low loss H-shape SIW hybrid coupler for millimeter-wave phased arrays antenna systems

A simple low loss H-shape hybrid coupler based on the substrate integrated waveguide technology is presented for millimeter-wave applications. The coupler operation is based on the excitation of two different modes, TE₁₀ and TE₂₀. The coupler S-matrix is calculated by using a full-wave solver that uses the even/odd mode (symmetry) analysis to minimize the computational time and provides more physical insight. The simulated return and insertion losses are better than -20 dB and -3.90 dB, respectively over the operating frequency bandwidth of 39-40.50 GHz.