Method for operating an ad-hoc network for the wireless data transmissions of synchronous and asynchronous messages

• US 7,349,339 B2
• Filed: 12/14/2001
• Issued: 03/25/2008
• Est. Priority Date: 12/14/2000
• Status: Expired due to Fees

• Current Assignee: 7 Layers AG
• Original Assignee: 7 Layers AG
• Inventors: Horn, Michael, Meckelburg, Hans-Jürgen
• Primary Examiner(s): Levitan; Dmitry
• Application Number:
  US10/450,690
• Publication Number:
  US 20040063401A1
• Time in Patent Office: 2,293 Days
• Field of Search: 370229-2301, 370/235, 370/310, 370343-345, 370/351, 370/400, 370/431, 370/436, 370/437, 370/442, 709/227, 709/228, 709230-236
• US Class Current: 370/235
• CPC Class Codes: H04L 45/302 Route determination based on requested QoS
• CPC Class Codes: H04W 28/26 Resource reservation
• CPC Class Codes: H04W 40/00 Communication routing or communication path finding
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A method for operating an ad-hoc network for the wireless data transmission of synchronous and asynchronous messages synchronizes the transmitters and receivers of neighboring nodes on a transmission path using cyclically transmitted identifiers, whose intervals define a time frame. The nodes of the transmission path reserve time slots within the time frame for the transmission of data packets of a virtual connection that are to transmitted synchronously. A start signal is transmitted at the stars of the synchronous transmission of a virtual connection, the data packets are then transmitted in the previously defined time slots and the synchronous transmission is concluded by a stop signal. Free time slots in the nodes are filled with data packets that can be transmitted asynchronously, the packets being read from an output buffer memory of the node.

Claims

1. A method for the operation of an ad hoc network for wireless transmission of synchronous and asynchronous messages,

where the network is composed of network nodes that are distributed in any desired manner, each of which has a receiving device having an input controller, a switching station, and a transmitting device having an output controller,

where transmission paths for logical connections to be transmitted from a starting node to a target node are established by way of intermediate nodes, according to a routing method, and

where the nodes administer local address and control data (LCI) that are assigned to the logical connections and are reported to a preceding node of the transmission path,

wherein

the messages are transmitted according to a frequency multiplex method, in the form of symbol vectors, which comprise a fixed, predetermined number of symbols transmitted in parallel,

the transmitting and receiving devices of adjacent nodes of a transmission path are synchronized, using cyclically transmitted identifiers whose periodicities define a time frame,

the nodes of the transmission path reserve time slots within the time frame, for transmitting symbol vectors of a logical connection to be transmitted synchronously, where a start signal is sent a synchronous transmission of the logical connection begins, subsequently data packets are transmitted in the reserved time slots, and the synchronous transmission is terminated by a stop signal,

after determination of a transmission path for a logical connection to be transmitted synchronously, a check is made as to whether the time slots required for the synchronous transmission are available on radio channels, whether all the nodes of the transmission path reserve the time slots, and whether a preceding node reports the local address data and the reserved time slot,

in the determination of the transmission path and the time slots for a connection to be transmitted synchronously, a time delay is proposed at a node whenever two independent logical connections between two nodes claim the same time slot, where all time delays of the transmission path, from the starting node to the target node, are added to obtain a total time delay, the total time delay for the synchronous transmission not being allowed to exceed a predetermined value,

if the total time delay is less than or equal to the predetermined value, synchronous transmission is permitted for the connection and if the total time delay exceeds the predetermined value, synchronous transmission is not established for the connection, and

any free time slots in the nodes are filled up with messages transmitted asynchronously, in a form of symbol vectors, each symbol vector having a respective header for identifying the symbol vector and being read out from an output buffer of the node.

2. The method according to claim 1, wherein system-specific symbol vectors for synchronization of the transmitting and receiving device of adjacent nodes along a transmission path are transmitted within the established time frame.

3. The method according to claim 2, wherein a number of empty vectors is transmitted within the time frame, which are removed in a node, as needed, in order to eliminate synchronicity errors between the receiving devices and transmitting devices of the adjacent nodes.

4. The method according to claim 1, wherein an error recognition and correction via a symbol vector or via a symbol stream that is transmitted in parallel takes place.

5. The method according to claim 1, wherein the symbol vectors of a receiving channel that arrive at a node are switched to a transmitting channel that is different from the receiving channel, where the symbols associated with a symbol vector are forwarded and transmitted in parallel.