initial commit to make it work on non Apple Computers
implemented dummy method to send RSSI values
Changed Vehicle to use a Propagation model when sending RSSI values.
Added Dummy Implementation for a Propagation model
modified Vehicle to send beacons to RSUs.
fiexed Vehicle to send beacons to RSUs without crashing the simulation.
added PropagationModel class for rssi calculation
Changed Vehicle and RSU to use the PropagationModel when sending rssi
values. rssi values are stored in KnownVehicle/RSU for further usage.
added a method to calculate the distance from rssi values