Research And Design Of Array Antenna Based On CMMPT

With the development of modern science and technology,array antennas are gradually used in satellite communication,wireless energy transmission,microwave hyperthermia and other application fields,which places a higher demand on antenna technology.Array antennas have higher gain and directivity than a single antenna unit,and can achieve special radiation performance by giving different excitations to the ports.In this paper,the power transfer efficiency is taken as the optimization objective,and the constrained maximum power transmission efficiency method(CMMPTE)is used to optimize the design of dual-frequency circular polarization reconfigurable array antenna,which ensures that the circular polarization beam has a low cross polarization level and axial ratio in the large-angle scanning.Then,the wireless power transmission system with a specific energy distribution is then optimized by the CMMPTE method,which constrains the electric field values at the sampling points in the target region and achieves a three-dimensional shape distribution of the electric field in the near-field region.This paper mainly carried out the following research:1.Firstly,a circularly polarized reconfigurable array antenna for Ka-band satellite communication is designed,which is a dual-band circularly polarized reconfigurable array antenna with a simple structure and a low profile.In this paper,the dual-port receiving antenna is placed in the far field area where the beam of the array antenna needs to be directed,and the circularly polarized beam is optimized by polarization constraints to achieve a circularly polarized beam that maintains a low cross-polarization level and axis ratio during scanning.Two beamforming controllers working in the transmitting and receiving frequency band are designed,and the antennas are manufactured and measured in the microwave anechoic chamber.The measured results matched well with the simulation results,which confirms the feasibility of the proposed method.2.Then,a near-field three-dimensional shaped array antenna is designed by using CMMPTE to optimize the wireless power transmission system with specific energy distribution.By taking the electric field value of the sampling point in the target region as the constraint condition,the power transmission efficiency can be maximized while the expected shape of electric field is achieved.Compared with traditional CMMPTE,this method no longer necessary to place the receiving antenna for optimization,and has higher freedom in practical applications.In this paper,the near-field three-dimensional shaped array antenna achieves sphere-shaped electric field distribution and offset distance in the desired direction.Finally,it is verified that the method also achieves good three-dimensional shaping effect in solution environment.