Decentralized and synchronous data transmission process and network

• US 4,930,124 A
• Filed: 09/21/1987
• Issued: 05/29/1990
• Est. Priority Date: 11/21/1985
• Status: Expired due to Fees

• Current Assignee: Thomson-CSF
• Original Assignee: Thomson-CSF
• Inventors: Salvan, Michel, Gugenhein, Michele, de Boisseron, Bertrand
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Jung, Min
• Application Number:
  US07/086,082
• Time in Patent Office: 981 Days
• Field of Search: 370/94, 370/54, 370/58, 370/85, 370/60, 370/95, 370/86, 370/89, 370/92
• US Class Current: 370/400
• CPC Class Codes: H04W 40/12 based on transmission quality or channel quality
• CPC Class Codes: H04W 56/004 compensating for timing error of reception due to propagation delay

Abstract

A process and network are provided for data transmission between a plurality of transmitting/receiving stations, called participants. The network is synchronous and decentralized. The connections between stations are omnidirectional in nature and the communications take place at the same frequency in accordance with a time multiplexing principle. Each of the different participants have one or more predefined transmission times towards one or more participants, also predefined, all of which is within a cycle.

Claims

1. A method of data transmission between a plurality of stations, called participants, capable of transmitting and/or receiving data, wherein the data is transmitted by the participants by way of time multiplexing, each of the participants having a predefined transmission time within a period of time called a cycle wherein said cycle is divided into sequences and, for each sequence a single predefined participant may transmit data which is designated to one or more predefined participants;

said method comprises at least one step for the initial synchronization of all of the participants with each other and, prior to any transmission of data other than synchronization data, the method further comprises a routing step, determining the participant receiving data information to be transmitted wherein said data information is a function of the final destination of said data information and of the quality of the communication links between participants wherein said quality is based upon prior error counts of said connections.

2. The method as claimed in claim 1, wherein said step for the initial synchronization of the participants with each other takes place based upon one of the participants being designated as an origin, with all of the other participants not taken as the origin receiving data from the participant designated as the origin, being called a participant of the first type and which, synchronize themselves in a first stage, at the reception of a first message transmitted by the origin and then, in a second stage, correcting this synchronization of the actual travel time of a message between the origin and, with the synchronization of any given station, wherein any given station is synchronizing itself at a later time which is determined by the original participant upon the reception of a second message from a participant of the first type.

3. The method as claimed in claim 2, wherein those of the participants, called participants of second type, which are other than the original participants of the first type, who receive the data transmission from a participant of the first type, synchronize themselves to the participants of the first type in the same manner as the original participants, as set forth in claim 3.

4. The method as claimed in claim 3, further comprising:

a step of maintaining the synchronization, for each participant, by synchronizing itself, in the same manner as set forth in claim 3 based upon each message which it receives from the participant who provided said participants initial synchronization, and correcting this synchronization by the actual travel time which it has stored during said stations'"'"' initial synchronization.

5. The method as claimed in claim 4, further comprising a step for updating the travel time.

6. The method as claimed in any one of claims 1, 2, 3, 4, or 5, further comprising an additional step:

for compilation by each of the participants, of statistical data concerning the type, number of errors in each of the connections to which each of said participants is connected, followed by a step for transmitting these statistics to the same participant, followed by a step for transmitting these statistics to all of the other participants.

7. The method as claimed in claim 6, wherein the routing step is achieved by consulting a table based upon the simplest path which has been corrected by the quality of link data, elaborated by each participant on reception of the statistics, and giving the best paths between the participants as a function of the quality of the connections.