Earlier in the year on YouTube, Yaniv Hoffman and Occupy The Web haved discussed research showing how Wi-Fi signals can be used to detect and track people through walls. The idea is simple from an RF point of view. Wi-Fi is just radio, and when those signals pass through a room they reflect and scatter off walls, furniture, and human bodies. By analyzing these reflections, it is possible to infer movement and even rough human outlines without placing any hardware inside the room.
Using low-cost SDRs, a standard PC, an NVIDIA GPU, and open-source AI tools like DensePose, researchers can reconstruct basic 3D human shapes in real time. In some cases, the system does not even need to transmit its own signal. It can passively analyze reflections from an existing Wi-Fi router already operating in the home.
The speakers note that this raises obvious privacy concerns. While there are some benign uses like motion-based home security or monitoring breathing in elderly care, the same techniques could be misused. Countermeasures are limited, as Wi-Fi uses spread spectrum techniques that make jamming difficult.
If you're interested, we posted about something similar in 2015, where USRP radios were being used to detect the presence of people behind walls.
They’re Watching You Through Wi-Fi… And You Have No Idea
In April, a stock research firm told clients that a Gulfstream V owned by Houston-based Occidental Petroleum Corp. had been spotted at an Omaha airport. The immediate speculation was that Occidental executives were negotiating with Buffett’s Berkshire Hathaway Inc. to get financial help in their $38 billion offer for rival Anadarko Petroleum Corp. Two days later, Buffett announced a $10 billion investment in Occidental.
There’s some evidence that aircraft-tracking can be used to get an early read on corporate news. A 2018 paper from security researchers at the University of Oxford and Switzerland’s federal Science and Technology department, tracked aircraft from three dozen public companies and identified seven instances of mergers-and-acquisitions activity. “It probably shouldn’t be your prime source of investing information, but as a feeder, as an alert of something else what might be going on, that’s where this work might be useful,” says Matthew Smith, a researcher at Oxford’s computer science department and one of the authors.
"Alternative data" collection firms like Quandl Inc. have services like "corporate aviation intelligence", where they use ADS-B data to keep tabs on private aircraft, then sell their data on to hedge funds and other investors who are hoping to gain an edge in the stock market.
Popular flight tracking sites that aggregate ADS-B data like FlightAware and FlightRadar24 censor data from private jets on their public maps upon the request of the owner, but it's not known if they continue to sell private jet data on to other parties. ADS-B Exchange is one ADS-B aggregator that promises to never censor flights, however the data is only free for non-commercial use. The value from using companies like Quandl is that they probably have a much more accurate database of who each private jet belongs to.
