Vehicle control system and mobile device used as vehicle key fob

A method of vehicle control for a vehicle including a vehicle computer configured to perform one or more smartkey-enabled features responsive to a smartkey present at the vehicle generating a successful response to a challenge from the vehicle computer, the method comprising:

• establishing a Radio Frequency (RF) communication link between an RF transceiver of a vehicle control system (VCS) at the vehicle and an authorized mobile device, the authorized mobile device being authorized to access one or more of the smartkey-enabled features of the vehicle;
• receiving by the VCS through the RF communication link a command corresponding to a smartkey-enabled feature;
• with the smartkey absent from the vehicle, selectively emulating with the VCS the presence of the smartkey at the vehicle by
• sending the command corresponding to the smartkey-enabled feature from the VCS to the vehicle computer,
• receiving by the VCS the challenge from the vehicle computer, and
• generating at the VCS an appropriate response to the challenge for the vehicle computer to make it appear to the vehicle computer that the smartkey is present at the vehicle for causing the smartkey-enabled feature to be performed by the vehicle computer.

A method of vehicle control for a vehicle including a vehicle computer configured to perform one or more smartkey-enabled features responsive to a smartkey present at the vehicle generating a successful response to a challenge from the vehicle computer, the method comprising:

• establishing a Radio Frequency (RF) communication link between an RF transceiver of a vehicle control system (VCS) at the vehicle and an authorized mobile device, the authorized mobile device being authorized to access one or more of the smartkey-enabled features of the vehicle;
• obtaining distance estimate from the vehicle to the authorized mobile device;
• receiving by the VCS through the RF communication link a command corresponding to a smartkey-enabled feature;
• and
• when the distance estimate is less than a limit, and with the smartkey absent from the vehicle, selectively emulating with the VCS the presence of the smartkey at the vehicle by
• sending the command corresponding to the smartkey-enabled feature from the VCS to the vehicle computer,
• receiving by the VCS the challenge from the vehicle computer, and
• generating at the VCS an appropriate response to the challenge for the vehicle computer to make it appear to the vehicle computer that the smartkey is present at the vehicle for causing the smartkey-enabled feature to be performed.