Indeed, that is how a radio antenna works, except that the weak current generated by the radio waves has to be amplified to do its job of carrying a signal round a radio.

而收音机的天线就是这样工作的，只不过电波所产生的电流非常弱，需要进一步放大从而完成信号传输。

youdao

That's because the prototype gadget, which works with an antenna and other components, made with nanoparticles of silver and other materials on an inkjet printer, can draw energy out of thin air.

这种雏形设备由纳米银颗粒和用在喷墨打印机上的其它材料制成，并与天线和其它组件配合使用，可以从稀薄的空气中获取能量。

youdao

How it works: a 2-metre antenna and mobile generator produce and aim a beam of 95-gigahertz (3-millimetre) radiation.

工作原理：一个两米长的天线和移动发电器制造95束千兆赫(3毫米)的辐射对准目标。

youdao

The fact is that HD via ATSC only works in applications where the antenna is stationary, which means that cable or satellite work just as well, but of course aren't free.

ENGADGET: Ask Engadget HD: Should the FCC kill DTV for better technology?

"If WIMAX technology a technology a lot of folks are talking actually works you can put an antenna on a tower downtown and the whole downtown is connected with very fast broadband, " he says.

NPR: Broadening the Reach of Broadband

It can work out where pheromone molecules are coming from by comparing the signals from each antenna, in the same way that a person works out the direction of a sound by comparing signals from each ear.

ECONOMIST: Robomoths | The