The embodiments relate to an image reconstruction to be carried out on a base unit of a MRI system, where data is formed by reception signals obtained by a local coil unit. Provisions are made for an alternating magnetic field, modulated in accordance with a reference clock, the alternating magnetic field to be used by the local coil unit for obtaining electric energy for supplying local electronics of the local coil unit and the reference clock to be retrieved from the received alternating magnetic field by the local electronics, a radio signal containing MRI information representing the reception signals and clock information representing the retrieved reference clock to be produced by the local electronics and transmitted to the base unit, and the received radio signal to be processed by the base unit such that the data and the clock information are retrieved therefrom and provided for the image reconstruction.