Abstract：Flat-topped beams can provide a uniform power density to the receiver in wireless power transmission, which is of great significance to improve the receiving efficiency and to simplify the design of rectifier circuit. This paper firstly studies the conditions of realizing flat-topped beam based on the Orchard synthesis by moving the zero points positions on the Schelkunoff’s unit circle; secondly, it introduces the Sinc function and gives the relationship between the solution and the width of a flat-topped beam; finally, it discusses the relationship between the width and three parameters, rectangle coefficient, ripple factor, and side lobes level by using perturbation method and numerous calculations. An example of ten-element array is given to illustrate the procedure of achieving the narrowest flat-topped beam with a side lobe level less than verifying the efficiency of the methods and conclusion in this paper.
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