In Airshark: Detecting Non-WiFi RF Devices using Commodity WiFi Hardware (PDF), researchers from U Wisconsin (Madison) document a firmware for WiFi access points that can detect and dynamically adjust to interference from vacuum cleaners, baby monitors, and other non-WiFi devices that operate in WiFi's radio spectrum. This kind of thing is the backbone of the theory of cognitive radio: devices that can use software defined radio, phased-array antennas, and cleverness to route around other devices in the band, which may, eventually, enable the a lot more data to occupy the radio spectrum. In Airshark's case, the cleverness is in using the wireless cards on the computers and other devices as a sensing array to triangulate on interference.
Airshark taps into the application programming interface of wireless cards used on access points to gather data about radio frequencies in the surrounding environment. The software has been trained to recognize signatures of various devices, and can pick them out from the ambient radio noise with more than 90% accuracy even if signals from multiple such devices are present.
False positives were .39% for environments with four or more interfering devices and using various signal strengths. The researchers found the rate was .068% for signals stronger than -80dBm. "We also found its performance to be comparable to a commercial signal analyzer," according to their research paper "Airshark: Detecting Non-WiFi RF Devices using Commodity WiFi Hardware."
Behold, the Blue Marlin, a “semi-submersible heavy lift ship” that is capable of hoisting and transplanting other, full-sized ships (that is ships as big or bigger than a US Destroyer-class vessel) all around the oceans.
Mister Alphabet is an action-figure designed to cleverly bend and contort into every letter of the Latin alphabet; the website is long on trademark warnings and arty Instagram photos, but short on details, like, “Is this an object of commerce?” and “If so, where does one buy it?” (via Kottke)
Phone chargers usually only deliver a few volts of juice at a feeble amperage, but they’ll deliver a lot more if you give them the chance. The BBC writes that a UK man died in the bathtub after being shocked by a charger connected to an extension cord. Richard Bull, 32, died when his iPhone […]
What could be more fun than a slingshot that shoots tiny airplanes? A slingshot that shoots tiny glowing airplanes of course! These toy planes are outfitted with ultra-bright LEDs, so you can fly all night without losing them in the trees.Whether you are a regular-sized child, or an overgrown adult one, these light-up flyers offer […]
You know the drill. You go to the dentist and they ask you how often you floss. You lie through your teeth and say, “every day!” (Bonus points if you have some cilantro or chives stuck in your gums from lunch). You don’t want to keep up the charade any longer, but rubbing that tiny strand […]
The Raspberry Pi Foundation has done outstanding work packing a fully capable desktop computer into a package the size of a deck cards—especially one that only costs $35. But if you already have a working laptop, why should you care? Oh, how much you have to learn. Besides operating well as a compact digital media hub, […]