Method and device for wireless topology discovery for train backbone networks

A device for wireless topology discovery for train backbone networks, comprising:

• a receiver, for receiving topology frames and hello frames over a receiving channel frequency, by a backbone node in a train backbone network data from a neighbor backbone node of the backbone node, through one directional antenna of at least one pair of directional antennas provided thereon, each antenna in the pair having a different frequency band,
• a recorder, for recording a receiving direction of said data, and determining said data to be a hello frame or a topology frame,
• a neighbor discovery processor, for performing neighbor discovery or topology discovery based on a type of said data, and in neighbor discovery phase, performing a pair consistency checks on the data received by the backbone node along a same direction, so as to identify a neighbor of the backbone node, and simultaneously, stopping receiving hello frames along said direction by the backbone node,
• a topology store, for updating a local topology table of the backbone node based on received topology frames in topology discovery phase, and
• a topology generator, for performing a topology convergence check to determine whether any change occurs to the local topology table of the backbone node during a period of time, and, reporting a status of the topology discovery phase to a high-level application if no changes occur;
• wherein the backbone node transmits over a transmission channel frequency that is different than the receiving channel frequency, and
• wherein the backbone node performs the topology discovery in one direction of the train backbone network and the topology discovery in the other direction of the train backbone network.

On a car in an elongated serial succession of cars disposed along a linear or curved path, the car disposed between a first adjacently neighboring car on one side thereof along the path and a second adjacently neighboring car on another side thereof along the path, a network backbone node disposed on the car, the network backbone node comprising:

• an RF transceiver configured to communicate point-to-point with a first neighboring backbone node on the first neighboring car using a first directional antenna operating on a first frequency band and aimed along the path in a first direction, and to communicate point-to-point with a second neighboring backbone node on the second neighboring car using a second directional antenna operating on a second frequency band different from the first frequency band and aimed along the path in a second direction different from the first direction;
• a data discriminator connected to the RF transceiver, the data discriminator determining:
• (a) whether received data was received in the first direction or the second direction, and (b) whether said received data comprises a hello message or a topology message indicating network topology along the path beyond the car and the first and second adjacently neighboring cars;
• and
• a topology discovery processor coupled to the data discriminator, the topology discovery processor discovering network topology based on the received data, the topology discovery processor performing a pairwise consistency check on data received in a common direction to confirm the received data is from an adjacently neighboring car along the path, the topology discovery processor updating a stored network topology representation based on received topology messages, performing a topology convergence check to detect changes in the network topology representation over time, and reporting detected topology changes to an application,
• wherein the network backbone node performs the topology discovery in one direction of the train backbone network and the topology discovery in the other direction of the train backbone network.