An Improved Switched-line Phase Shifter Using Distributed MEMS Transmission Line
In this paper a new switched-line phase shifter is designed using Distributed MEMS Transmission Line (DMTL) instead of conventional transmission line. DMTL is transmission line with loaded MEMS bridges. At first using simplified model of DMTL the improved structure is analyzed. The design is explained by describing SIB frequency which minimizes return and insertion loss. The design procedure of improved structure is presented using closed-form equations. The Ansoft HFSS is used for simulation and a comparison is made between conventional and improved structures. The results show the feasibility of new design. Also it shows that the improved structure has low size and low loss compared with conventional switched-line.The simulation results show that the phase shifter creates180 degree with the average insertion loss and return loss of -1.1 dB and -38.2 dB at 2.45GHz respectively which demonstrate an improvement in loss and isolation of the new switched-line.