Design And Research Of MEMS Phase Shifter Based On SPDT Switch

As a key microwave device in the phase control array,which adjusts the phase of waves,phase shifter is widely used in telecommunication and radar fields.Featuring high phase shifting accuracy,low insertion loss,high linearity and low cost,MEMS phase shifter is widely used in radar,electronic warfare,remote sensing,radiation measurement and other fields.This thesis has completed the design of high-performance RF MEMS SPDT switch and high-precision switching linear MEMS phase shifter,and completed the process and test of RF MEMS SPDT switch.Firstly,the RF MEMS SPDT switch,the core component of MEMS phase shifter,is designed and studied.By analyzing the substrate material and characteristic impedance of coplanar waveguide,the design of coplanar waveguide transmission line is completed.Then,two power divider structures,funnel-shaped and ladder-shaped,are proposed,and the design of RF MEMS SPDT switch with wide frequency band and high performance is completed.Secondly,the MEMS phase shifter is designed and studied.The theoretical calculation of delay line is completed by studying the working principle of switching linear MEMS phase shifter.The preliminary design of MEMS phase shifter is completed by cascading RF MEMS SPDT switch and extension line structure.By optimizing the corner structure and air bridge structure of the phase shifter,the design of two 4-bit switching linear MEMS phase shifters in K band and Ka band is completed.And the best simulation results are obtained through HFSS software simulation optimization.Finally,the processing and testing of RF MEMS SPDT switch,the core component of MEMS phase shifter,are studied.The layout and process flow design of RF MEMS SPDT switch are completed.Through MEMS processing such as electroplating,lithography and etching,the RF MEMS SPDT switch is prepared,and the RF MEMS SPDT switch samples are tested.The test results show that the driving voltage of RF MEMS SPDT switch is 60.1V,the switching response time is 57?s,the insertion loss is better than-0.48 d B and the isolation is better than-32 d B in the frequency range of 0.1?20GHz,and the RF MEMS SPDT switch has good microwave performance.