Abstract: A communication system with a master device configured to determine location information in real-time with respect to a portable device. The master device may direct one or more monitor devices to monitor communications that occur over a primary communication link. The monitor devices may sense characteristic information about the signal from the portable device, and communicate this characteristic information to the master device via an auxiliary communication link. The communication system may determine location of the portable device, authenticate the portable device, determine whether the portable device is authorized to allow or initiate an action, and command or enable an action with respect to equipment.

Abstract: A system and method for using a portable device to communicate with a vehicle to authorize one or more vehicle operations. The portable device may authorize the vehicle to unlock/lock doors, start the vehicle engine, or mobilize the vehicle, or a combination thereof. The vehicle may include a vehicle transmitter system with one or more transmitters disposed at various locations on the vehicle, and the portable device may be configured to monitor a communication strength between the portable device and the one or more transmitters of the transmitter system. Based on the monitored signal strength, the portable device may determine location information about itself.