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The graphs they present show the largest response with 110db audio, which is about as loud as a car honking right in front of you[1], but even still, to eavesdrop on corner offices from tens of meters away with nothing but a telescope and a video recorder is a huge feat.

[1] https://www.chem.purdue.edu/chemsafety/Training/PPETrain/dbl...

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That’s to be expected, but they could still recover audio at vastly lower DB levels.

Pointing a telescope at tens of meters away will get you noticed pretty quick. Now one can sell lightbulbs with noise modulation to defeat it.

Yeah, not sure why they patented the attack, and not the defense.

It seems much easier to enforce a patent against technologies that defeat the attack.

From the article, it looks like one can build the surveillance device from a few readily available parts, and then hack together the signal processing software. That’s not even in violation of the patent if you don’t sell / distribute it.

The attack obviously works only at night, when the light bulbs are on. Pretty sure you can easily disguise it.

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