A novel two-layer electronically controllable substrate integrated waveguide phase shifter

A novel approach to develop a digital phase shifter based on two-layer substrate integrated waveguide with the capability of electronic control is proposed in this paper. The phase shifter exhibits the properties of low insertion loss, wide relative bandwidth and good amplitude/phase imbalance performance. Wideband coupling technique with a transverse slot is used to guarantee the wideband performance. Electronic control is achieved by utilizing PIN diodes on transverse slots. Moreover, a simple equivalent circuit and analysis method is explained. The results of fabricated prototype agree well with the simulation. A phase shift of 90° with ≤ 1.5 dB insertion loss and 36% relative bandwidth (9 GHz to 13 GHz) is achieved for 15 dB return loss. Amplitude and phase imbalance is measured to be ±0.4 dB ±4°, respectively.