DEF CON 25 Wifi Village - Balint Seeber - Hacking Some More of the Wireless World

The hacking continues on from last year! Three interesting applications will be demonstrated, and their underlying theory and design explained. The audience will be exposed to some novel GNU Radio tips and DSP tricks. INMARSAT Aero will be revisited to show (in Google Earth) spatial information, such as waypoints and flight plans, that are transmitted from airline ground operations to airborne flights. A good chunk of the VHF band is used for airline communications; plane spotters enjoy listening to tower and cockpit communications. Modern SDRs can now sample the entire band, and as AM modulation is used, it's possible to use a counterintuitive, but simple, demodulator chain (first shown by Kevin Reid's wideband 'un-selective AM' receiver) to listen to the most powerful transmission. This will be demonstrated with a GNU Radio-based implementation. It is also possible to 'spatialise' the audio for the listener using stereo separation, which can convey a transmission's relative position on the spectrum. FMCW RADAR experiments are enhanced to include Doppler processing. Plotting this new velocity information, due to the Doppler effect, shows whether a target is heading toward or away from you, and often reveals targets not normally seen in range-only information - this demonstrates the true power of full RADAR signal processing. This technique will be applied to the live audio demo, a new live SDR demo, CODAR ocean current tracking, and passive RADAR exploiting powerful ATSC digital television signals (this was used to track aircraft on approach across the Bay Area).