An Innovative Reconfigurable Reflection-Type Phase Shifter for Dual Band WLAN Applications

This paper presents an innovative reconfigurable reflection-type phase shifter for dual band WLAN applications. The device allows an independent choice of the phase shifts for both the two WLAN bands, employing a quadrature hybrid dual band coupler, two diplexers and four reflective loads. A full 360deg phase shifter prototype has been realized in microstrip technology, the reflective loads being realized through eight varactors, whose capacitances are varied through two different biasing networks. Measured results show good performance in terms of return loss, insertion loss and excellent isolation between the two WLAN bands, confirming the feasibility of the proposed architecture and its applications to dual band smart antenna systems