A wheel unit for a system for transmitting data from the wheel unit to a receiver of a vehicle. The wheel unit is configured for mounting to a wheel of the vehicle, and the wheel unit includes the following: a memory for storing wheel type data related to the type of the wheel at which the wheel unit is mounted; a processor for processing the wheel type data stored in the memory; a transmitter for RF-transmitting data telegrams to a vehicle-mounted receiver. The processor determines an RF power value based on the stored wheel type data, and the transmitter transmits the data telegrams with an RF power based on the determined RF power value.