METHOD OF A VEHICLE FOR CONTROLLING THE TRANSMISSION POWER DURING THE COMMUNICATION WITH A VEHICLE KEY, AS WELL AS VEHICLE AND VEHICLE KEY

A vehicle-based communication system supports wireless data exchange with a vehicle key using ultra-high-frequency (UHF) radio. A control unit of the vehicle transmits a first message to a communication control device, the message indicating a transmission power to be set for a transceiver. The communication control device sets the UHF transmission power based on the message and activates the transceiver to transmit a data packet containing user data to the vehicle key. A low-frequency ping may establish a receive window during which the vehicle key receives the data packet. The vehicle key stores the received data packet, optionally transmits a checksum to confirm proper reception, and may adjust its own UHF transmission power based on the received data. The vehicle may re-transmit the data packet when an incorrect checksum is detected. The system enables flexible, software-based adjustment of UHF transmission power for reliable communication with the vehicle key.