1、[通信]射频频谱
...第一次first; for the first time射频频谱radio spectrum; radio-frequency spectrum状态变化change of state ...
2、射频频谱
...第一次first; for the first time射频频谱radio spectrum; radio-frequency spectrum状态变化change of state ...
Radio-frequency spectrum preface无线电频谱
automatic radio-frequency spectrum recording equipment自动无线电频谱记录设备