US 6,307,652 B1Granted

Fault tolerant optical communication apparatus and method

AssigneeWeed Instrument Company, Inc.

InventorsMohammed Fassih-Nia, Ernest A. Cisneros, Milton E. Cram, Donald Ray Taylor

Life of this patent

Estimating the term…

Loading patent…

Abstract

An optical communication system (11) includes a plurality of nodes (16,17,18,19), each node connected in a first optical communication path (22) and a second optical communication path (23) extending parallel to the first optical communication path. The first optical communication path (22) is joined to each node by a first receiver (30) and first transmitter (31), while the second optical communication path (23) is joined to each node by a second receiver (32) and second transmitter (33). One of the nodes comprises a control unit node (19) having a control unit (37) associated therewith. The other nodes of the communication system comprise data unit nodes, each having a data unit (36) associated therewith. The communication system (11) normally operates with the control unit (37) in an open mode of operation in which data is not transferred across the node. Thus, in normal operation, the communication system (11) operates in an open ring configuration. When a fault occurs on the optical communication path (22,23) between adjacent data units, the system detects the fault and switches the control unit (37) to a closed mode of operation in which data is transferred along both optical communication paths (22,23) across the control unit node (19).

Claims33

Dependent claims

An optical communication system comprising:

(a) a plurality of nodes, each node having associated therewith a first transmitter, a first receiver, a second transmitter, and a second receiver;
(b) a plurality of optical communication segments connecting the plurality of nodes together in a ring configuration having a first optical communication path and a separate, second optical communication path, the first optical communication path being joined at each node by the first transmitter and first receiver associated with the respective node, and the second optical communication path being joined at each node by the second transmitter and second receiver associated with the respective node;
(c) one of the nodes comprising a control unit node and having a control unit associated therewith, the control unit adapted for normally operating in an open mode and for operating in a closed mode when a communication fault occurs in either the first optical communication path or the second optical communication path, the open mode comprising a mode in which data is not communicated from the first receiver to the first transmitter and is also not communicated from the second receiver to the second transmitter, the closed mode comprising a mode in which data is communicated from the first receiver to the first transmitter and from the second receiver to the second transmitter;
and
(d) each node other than the control unit node having a data unit associated therewith, the data unit for transferring data from the first receiver to the first transmitter and for transferring data from the second receiver to the second transmitter of the respective node, the data unit also for transferring data to and from a control system device associated therewith.

2 more elements

A method of communicating between a plurality of nodes of a fiber optic communication system in which each node has associated therewith a first transmitter, a first receiver, a second transmitter, and a second receiver, with a plurality of optical communication segments connecting the plurality of nodes together in a ring configuration having a first optical communication path and a second optical communication path, the first optical communication path being joined at each node by the first transmitter and first receiver associated with the respective node, and the second optical communication path being joined together at each node by the second transmitter and second receiver associated with the respective node, the method comprising the steps of:

(a) transferring data from the first receiver to the first transmitter and from the second receiver to the second transmitter at the plurality of nodes except at a control unit node operating in an open mode;
(b) at each node transmitting from the first and second transmitters data transferred to the respective transmitter, said transmissions occurring over the optical communication segments;
(c) monitoring the first optical communication path and the second optical communication path for a communication fault;
and
(d) changing to a closed mode of operation at the control unit node in response to a communication fault sensed on either the first or second optical communication path, the closed mode of operation comprising a mode in which data is transferred from the first receiver of the control unit node to the first transmitter and from the second receiver of the control unit node to the second transmitter.

2 more elements

Dependencies are inferred from the claim text.