A researcher at Ettus (creators of the USRP line of software defined radios) has uploaded a video showing how he is using his USRP to help with frequency management at FPV time trial racing events.
One important technical challenge at these events is frequency management. FPV drones use many frequencies at around 2.4 GHz for control and 5.8/2.4/1.3 GHz for video. With many drones in the air it is important that frequencies are managed appropriately so as to not jam each others signals.
To try and solve this problem Balint has been using GNU Radio coupled with a USRP X310 software defined radio to get very wide band RF spectrum waterfall views of the 2.4 and 5.8 GHz bands. In the waterfalls he is able to see when control signals and video signals are transmitted and at what frequency, and is able to tell if any are overlapping and jamming each other.
The technology allows monitoring of both the full frequency spectrum used by 5.8ghz analog video transmitters, and 2.4ghz RC links. I imagine the software could also be expanded to allow the single receiver to decode and display all of the FPV video streams simultaneously for spectating and documenting races.