frequency trim频率微调frequencyn.频繁；频率frequency-discrimination method鉴频法frequency response characteristic频率响应特性Frequency of Optimum Transmission最优传输频率frequency and the displacement.计算与试验比较 ,吻合较好。frequency-modulated synchrotron调频同步加速器frequency correlation coefficient频率相关系数frequency translating transponder变频转发器frequency shift modulation system移频调制方式frequency-hopping communication跳频通信frequency control of mortor speed变频调速