The present invention concerns a method, a device, a mobile terminal and a base station for transferring data from a mobile terminal to a base station after a wireless resource enabling the transfer of the data from the mobile terminal to the base station has been allocated. The method comprises the steps, executed by the mobile terminal, of transferring, information indicating whether or not an allocated wireless resource is needed for the transfer of the data from the mobile terminal to the base station, the information indicating that no allocated wireless resource is needed for the transfer of the data from the mobile terminal to the base station being transferred by setting the power of pilot symbols to a null value, receiving, from the base station, allocation information indicating that the wireless resource is allocated to the mobile terminal when the information indicates that the allocated wireless resource is needed, and transferring the data to the base station in the wireless resource indicated as allocated to the mobile terminal.