# Friday math movie: Wireless data from every light bulb

By Murray Bourne, 19 Aug 2011

Many of us worry about the effect of wireless radiation on our bodies. And those towers pumping out data are very energy inefficient. Another concern is how insecure wireless communications can be.

Perhaps there's a better way?

Engineer Harald Haas demonstrates a clever alternative using LED lights. The concept is something similar to what we've had for ages with the (wired) telephone - part of the signal is a constant DC voltage (which is necessary for transmission over long distances) and on top of that is the voice signal. (See Composite trigonometric curves for some background.)

Bring it on, I say.

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