Recently I'm doing a project about broadcast my location infos (latitude, longitude, bearing and speed) from gps module in smartphone, then ppls or drivers who are closer to each other could get the distance and avoid the collision(actually part of the VANET). I wanna use the Wi-Fi Direct to broadcast these infos without establishing connections among the devices. Just fill the infos into the name of Wi-Fi Direct ssid and change it when gps data changes. Then a problem occurs that the delay is really long. When I switched on the Wifi Direct of one device, another one could find it after about 1 second. However it’s not enough when comes to the vehicular network. This problem became more terrible when changing the device name periodically. If anyone can tell me whether this method is feasible to do the collision avoidance job or not? If there are some better ways using android smartphones? Thanks a lot!
I'm assuming this is a proof of concept, because this approach will not work in a real autonomous vehicle- you have no authentication or proof that a broadcast isn't being faked. In a real solution wifi just doesn't work well, its based on the idea of sending packets to an access point that works as a gateway, not broadcasting data. You're better off with a dedicated wireless frequency and a broadcast protocol.
For a proof of concept without being willing to tinker at the kernel level I think you're pretty much stuck here. Depending on how big a course you're testing on you may be best off using a wireless AP with each vehicle hard coded to an IP address and sending the data to all others via IP. Another option may be to turn on the wifi hotspot of one or all of the devices and use the devices themselves as the AP. Thus the AP moves with the vehicles.