I Mapped an Entire Building’s RF Footprint Without Walking Inside. Here’s How. (opens in new tab)

Photo by Nathan Dumlao on Unsplash A 200$ drone, a 25$ SDR dongle, and an afternoon\. That’s all it took\. It started with a bet\. A friend — let’s call him Marcus — works in physical security\. He runs RF site surveys for corporate clients\. The kind of work where you walk into a building with a spectrum analyzer, a directional antenna, and a laptop, and you spend two days mapping every wireless signal in the place\. He charges $8K per survey\. I told him I could do the same thing from the p...