主频段 meaning in English

p-gsm

Diode switches or voltage controlled varactors implement dual - band resonators such that they can offer low impedance at the second harmonic of each frequency band , while , in some cases , presenting high impedance at the fundamental frequency as an rf choke circuit
利用二极体开关或电压控制变容器实施双频共振器以提供在双频操作中每一个频段之二阶谐波的低阻抗，同时在一些实施例里也提供主频段的高阻抗、兼具有射频阻塞电路作用。
The research results show that the frequency zone is very wide during deformation and fracture process of loaded coal , the main frequency zone is changed with load change ; at the initial stage of the load the main frequency zone of eme is low , and sometime it takes on the trend from raise to drop ; at the later stage of the load the main frequency zone of eme is high , and its trend is that the larger the load is , the higher the main frequency zone is
研究结果表明，在受载煤体变形破裂过程中电磁辐射的频带很宽，其主频段随载荷的变化而发生变化，在受载初期，电磁辐射的主频带较低，电磁辐射主频带有时呈现先增高而后降低的趋势；在受载后期，电磁辐射的主频带较高，基本上表现为载荷越大，电磁辐射的主频段越高。