That doesn't mean it's impossible to prevent relay attacks, it's just that people choose not to. Additionally, the highway scenario could also be mitigated wit

That doesn't mean it's impossible to prevent relay attacks, it's just that people choose not to. Additionally, the highway scenario could also be mitigated with a warning and a grace period. The desert scenario can be mitigated with having a fallback such as having the contactless system double as a smartcard you can put into a reader or by wireless power transfer. Plus, if your contactless system fails in the desert you're screwed anyway as soon as you turn off the engine once.