Wifibroadcast

Wifi is almost everywhere and used for many purposes – it works well for many tasks but is not optimal for all. Wifibroadcast Makes WiFi FPV Video More Like Analog article tells that normal WiFi is not what you want to send video from your quadcopter back to the first-person-view (FPV) goggles strapped on your head. The reason for that is that WiFi is designed for 100% correct, two-way transmission of data between just two radios: When you’re near the edge of your radios’ range, you care much more about getting any image in a timely fashion than about getting the entire video sequence correctly after a delay. And that’s why [Befinitiv] wrote wifibroadcast: to give his WiFi FPV video system some of the virtues of analog broadcast -  dd in a custom retransmission routine that helps limit lost packets, and even allow multiple receivers to listen in to the same signal. The needed hardware is two Raspberry Pis combined with WiFi radios.

Wifibroadcast – Analog-like transmission of live video data article tells that Wifibroadcast puts the wifi cards into monitor mode. This mode allows to send and receive arbitrary packets without association. Additionally, it is also possible to receive erroneous frames. Not all wifi cards are compatible with wifibroadcast (the test were made with ATHEROS AR91729. This is because wifibroadcast uses injection mode which not fully supported by most wifi chipsets.

I have not tried this hack, but this looks interesting.