Fault tolerant optical cross-channel data link

United States Patent [19]

Goossen et al.

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIUIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIU

US0O5396357A

[ii] Patent Number: 5,396,357 [45] Date of Patent: Mar. 7, 1995

[54] FAULT TOLERANT OPTICAL CROSS-CHANNEL DATA LINK

[75] Inventors: Emray R. Goossen, Albuquerque, N.

Mex.; Larry A. Nelson, Bellevue,
Wash.; James W. Woods,
Albuquerque, N. Mex.

Assignee: Honeywell Inc., Minneapolis, Minn.

Appl. No.: 187,420

Filed: Jan. 25, 1994

[73]

[21]

[22]

[51] [52]

[58] [56]

Int. CL« H04B 10/20; H04J 14/00

U.S. Q 359/119; 359/110;

359/127; 359/152; 370/16.1; 371/20.6;

340/825.05

Field of Search 359/118-119,

359/110, 124, 125, 127, 152, 164; 370/16.1, 124;

340/825.05; 371/20.6; 364/713

References Cited

U.S. PATENT DOCUMENTS

4,704,713 11/1987 Haller et al 359/119

4,889,404 12/1989 Bhagavatula et al 359/124

4,947,459 8/1990 Nelson et al 359/110

4,973,169 11/1990 Slonecker 359/124

4,991,229 2/1991 Nelson et al 359/144

5,035,375 7/1991 Friedenthal et al 244/3.12

5,278,824 1/1994 Kremer 370/16.1

5,307,353 4/1994 Yamashita et al 371/20.6

FOREIGN PATENT DOCUMENTS

9110298 7/1991 WIPO 359/119

A cross-channel data link for interconnecting a plurality of computers together in a ring configuration using a single optical fiber between adjacent communication nodes includes wavelength division multiplexing circuitry in a way that improves the fault diagnostic capabilities of the system. By using a particular transmission protocol in which optical data representing signals of two discrete wavelengths are fed through a single optical fiber with one progressing in the clockwise direction and the other in a counterclockwise direction in two recurring time frames, at the conclusion each of the computers is guaranteed to have identical data irrespective of any single point failure in the data link.

6 Claims, 3 Drawing Sheets