Method for Synchronization and Data Transmission in a Multi-Hop Network

A method for synchronization and communication in a multi-hop network having a multiplicity of nodes and a central node, each of which having at least one transmitting/receiving unit, a storage unit and a processor unit, with communication between the transmitting/receiving units being based on wireless data transmission in frames, which are subdivided into defined slots, the nodes and the central node being spatially positioned in relation to each other in such a manner that at least one further node and/or the central node is located in the transmitting/receiving range of each node as its neighbor, communication between a node and the central node, if the node is located outside the central node's transmitting/receiving range, occurring utilizing further nodes as intermediate nodes via a multi-hop communication, and each node being assigned a hop count value giving the number of intermediate nodes raised by one for the respective node via which communication with the central node occurs, with the nearest intermediate node of the respective node in the network during communication with the central node being referred to as the node's predecessor, the node as successor of the intermediate node and all the nodes with the same hop count values being referred to as layer, comprising the following process steps:

• a) Transmission of a synchronization signal by the central node or a previously synchronized node, with the slot in the frame of the synchronization signal, the so-called beacon slot, determined by the node transmitting the synchronization signal being assigned a data package, the so-called beacon, and at least the hop count value of the transmitting node being transmitted in the frame of the synchronization signal, and, for all the previously synchronized neighbor nodes of the transmitting node known to the transmitting node, transmission of the respective beacon slots and the hop count values in the frame of the synchronization signal or as a separate data signal by the transmitting node,
• b) Reception of the synchronization signal and the data transmitted in connection therewith by a first node lying in the transmitting/receiving range of the transmitting node,
• c) Synchronization of the first node to the synchronization signal,
• d) Detection by the first node of its neighbors and their respective beacon slot assignment and hop count values,
• e) Determination of the predecessor of the first node in the network by the first node on the basis of given criteria,
• f) Storage by the first node of the data received with the synchronization signal as well as data received in connection therewith and determined therefrom,
• g) Repetition of steps a) to f) at least until synchronization of all the nodes.