a frequency or band of frequencies that lie in the range 10 kilohertz to 300 000 megahertz and can be used for radio communications and broadcasting 无线电频率 (Abbreviations rf, RF)
Many of them were using a pea-sized speaker to receive the answers over a radio frequency. 很多人借由一个豌豆大小的耳机来通过无线电频率接收答案。
Having the antenna at the bottom means less radio frequency waves are flooding the sensors. 将天线安置在底部意味着传感器会探测到最少的电磁波。
Underlying the Internet of Things are technologies such as RFID (radio frequency identification), sensors, and smartphones. 物联网背后的技术包括RFID(无线射频识别),传感器和智能手机。