Design And Research Of Phased Array Antenna Based On RF MEMS Switch

Phased array antenna whose electronically scanning method has the advantages of fast scanning speed and high scanning precision and so on is an important component of phased array radar.Phase shifter is the key component to control phase scanning of phased array antenna.Based on the ferrite materials,the PIN diode,and FET switch,the traditional phase shifter was difficult to develop in high Frequency band due to loss of problems.However,the emergence of RF MEMS(Radio Frequency Micro-company Mechanical System,RF MEMS)technology provided method to solve this problem.The RF MEMS switches has many advantages,such as low insertion loss,high isolation.The application of RF MEMS switch to phase shifter and MEMS phase shifter to phased array antenna can improve the performance of phased array antenna.This paper designs a phased array antenna unit of MEMS phase shifter with backto-back multilayer and stacked structure.The advantage of this structure is to reduce the space occupied by the antenna radiation unit and phase shifter and achieve miniaturization.The antenna radiation unit and MEMS phase shifter are not on the same side,which improves the radiation performance of the antenna radiation unit.Firstly,the modeling and simulation of the antenna radiation element are carried out.Secondly,modeling and simulation of ground coplanar waveguide(GCPW)are carried out,and good RF performance is obtained.Thirdly,the modeling and simulation of other components of MEMS phase shifter are carried out,and combine each component to carry out the modeling and simulation of one-bit phase shifter.And three one-bit phase shifters are cascaded together to carry out the modeling and simulation of three-bit switch-line phase shifters,and to carry out optimization,so as to obtain good RF performance.Finally,according to the simulation results of the antenna radiation unit and the three-bit switch-line phase shifter,the directional diagram results of the phased array antenna with array size of 1*4 without considering the loss and considering the loss are given,and the maximum gain is 12.5dB and 12.0dB respectively.This paper design the processing technology of phased array antenna,including microstrip patch antenna,substrate bonding,MEMS phase shifter process design.