Method for optimizing sum and difference beams of array antenna with cover

The invention discloses a sum and difference beam optimization method for an array antenna with a cover. The method comprises the following steps: creating an array antenna model and an array antenna model with a cover; respectively carrying out quadrilateral mesh generation on the models; based on the quadrilateral grids correspondingly subdivided by the model, respectively performing simulation calculation by adopting a high-order moment method, and extracting corresponding active unit directional diagrams; excitation is applied to an antenna unit in the model, sum and difference beams corresponding to the model at different scanning angles are calculated in combination with an active unit directional diagram, and corresponding performance indexes are compared; an improved hybrid differential evolution algorithm is adopted to carry out optimization design on sum and difference beams of the array antenna model with the cover, wherein the sum and difference beams do not meet the index requirements; wherein th