Spectrum sensing technology is a key component of cognitive radio whose function is to find out the empty frequency bands quickly and reliably.

频谱检测是感知无线电的关键技术之一，要求感知用户可靠、快速地检测频谱空洞。

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Weighing in at less than 9 ounces, it can control a component from as far away as 33 feet, and with an optional radio frequency receiver, it can control components in more than one room from farther away.

FORBES: True Remote Control