Star coupler : Wikipedia, the free encyclopedia

Star coupler

A star coupler is a device that takes in an input signal and splits it into several output signals.

In fiber optics, and especially in telecommunications, a star coupler is a passive optical device, used in network applications. An optical signal introduced into any input port is distributed to all output ports. Because of the way a passive star coupler is constructed, the number of ports is usually a power of 2; i.e., two input ports and two output ports (a "two-port" coupler, customarily called a directional coupler, or splitter ); four input ports and four output ports (a "four-port" coupler); eight input ports and eight output ports (an "eight-port" coupler), etc.

Digital Equipment Corporation (now part of Hewlett-Packard) of Maynard, Massachusetts sold a star coupler which interconnected links to computers via coaxial cable rather than optical fibres, but the function was essentially the same. The signal that was distributed was 70 Mbit/s computer interconnect (CI) data and the star coupler provided two redundant paths of either 8 or 16 ports each. Digital's star coupler was developed for use with the VAX- and later Alpha-based computers running Digital's OpenVMS operating system, to provide a passive, highly reliable interconnect for Digital's cluster technology.

References

Federal Standard 1037C. General Services Administration. Archived from the original on 2022-01-22.
FAA Glossary of Optical Communications Terms

Digital Equipment Corporation

Key people

Ken Olsen (founder and CEO, 1957–1992)
Harlan Anderson (co-founder)
Gordon Bell (VP of engineering)
Robert Palmer (CEO, 1992–1998)

Instruction set
architectures,
processors

PDP-11	LSI-11 F-11 T-11 J-11
VAX	V-11 MicroVAX 78032 CVAX SOC Rigel Mariah NVAX
Alpha	Alpha 21064 21066 21068 Alpha 21164 (21164PC) Alpha 21264 Alpha 21364 Alpha 21464
Other	MicroPRISM StrongARM