RTT measurements are hard to make reliable with wireless systems. You don't want to set the bounds to tight, to avoid locking out the car owner in circumstances

RTT measurements are hard to make reliable with wireless systems. You don't want to set the bounds to tight, to avoid locking out the car owner in circumstances with a lot of interference. But neither do you want a signal booster to be in those bounds. But there are better solutions. I've heard about a car maker (I think it was BMW, but don't quote me on that) that put an acceleration sensor in the key fob. It would only broadcast the signal while the key fob is moving.