Method for wire-free transmission of data packets between network nodes in a control network, wherein the data packets each have a preamble for synchronization, which preamble consists of a predetermined number of preamble symbols; wherein, in a first operating mode (FIG. 5a), each preamble-subsymbol (Cj, Cj+1) of a preamble symbol in the preamble is coded by the phase angle of a transmitted single signal pulse; wherein, in a second operating mode (FIG. 5b), in order to increase the signal recognition performance, for the preamble which is transmitted in the data packet, a signal pulse sequence (SIF) for coding the preamble-subsymbol (Cj, Cj+1) is transmitted instead of a single signal pulse, in which signal pulse sequence (SIF) the single signal pulse is transmitted repeatedly.