基于非线性优化方法研究了圆环单元频率选择表面（ＦＳＳｗ ｉｔｈ Ｃｉｒｃｕｌａｒ Ｒｉｎｇ ＵｎｉｔＣｅｌｌｓ）的设计问题，文中提出了圆环单元ＦＳＳ的新设计模型，探讨了该模型的计算方法．该模型可同时对影响ＦＳＳ频率特性的所有因素进行优化，并具有计算时间短、占用内存少的特点．仿真模拟结果表明，所提出的新模型及其计算方法可靠有效． Based on the nonlinear optimization method, the design problem of FSS ring  Circular Ring Unit (CFe) is studied. A new design model of FSS ring unit is proposed and the calculation method of the model is discussed. The model optimizes all the factors that affect the FSS frequency characteristics at the same time, and has the characteristics of short calculation time and less memory. Simulation results show that the proposed new model and its calculation method are reliable and effective.