中文摘要：

提出一种采用阶跃阻抗谐振器（SIR）设计双频天线的方法．通过建立天线的传输线模型，得到了双频天线的工作频率与传输线特性的关系式．然后，利用该方法设计了一个2．4／5．2GHz的小型化双频天线，其结构尺寸由工作频率直接综合得到．同时用电磁全波仿真，优化了天线的馈电位置．所实现的天线尺寸为29．3mm×7．7mm，相当于0．5λ×0．125λ．仿真和测试结果表明，采用阶跃阻抗谐振器设计双频天线的方法是可行且有效的．

英文摘要：

A design method of dual-band antenna by using stepped impedance resonator （SIR） is proposed. By establishing the transmission line model of the SIR dual-band antenna,the relation between the two operation frequencies and the characteristics of the transmission lines is obtained. Moreover, a miniaturized 2. 4/5.2 GHz antenna is designed by using the method. The geometry of the designed antenna can be synthesized directly from the operation frequencies. The designed antenna size is 29.3mm× 7.7 mm,about 0.5λ×0.125λ. Finally, the antenna is simulated and measured,and the results indicate that the design method of dual-band antenna by using SIR is feasible and effective.