Simplex and Duplex Fiber Optic Patch Cable Overview

When talking about fiber optic patch cable, related products that initially come into our mind are single mode and multimode fiber patch cable. However, there are still many other relevant terminologies such as multimode duplex LC LC cable, LC to LC duplex single mode patch cable and single mode simplex cable. For those who are new in this field, there is still much confusion about them. This paper will introduce simplex fiber patch cable and duplex fiber patch cable. In order to have a better understanding of simplex and duplex fiber optic patch cable, the definition of simplex and duplex will be explained in the first part.

What Do Simplex and Duplex Mean?

According to the ITU-T definition, a simplex circuit is one where signals can flow in only one direction at a time. One end is the transmitter, while the other is the receiver and that is not reversible. For example, in TV, audio or visual information flows from transmitter to numerous receivers.

However, at other times, communications can flow in the reverse direction. That is half-duplex. Half-duplex system means a communication channel that operates in one direction at a time and may be reversible. A good analogy for half-duplex system will be two roads with a traffic controller at each end, in order to ensure smooth flow of traffic, the traffic controller only allows one direction at a time. But if one party transmits at the same time, a collision occurs, resulting in lost messages.

“Duplex” comes from “duo” that means “two”, and “plex” refers to “weave” or “fold”. A duplex system has two clearly defined paths with each path providing information in only one direction, that is A to B over one path, B to A over the other. Compared with half-duplex, a full-duplex system, or sometimes called double-duplex allows communication in both directions and allowing this to happen simultaneously. Just like the cellphone, both parties can speak and be heard at the same time.

Simplex vs Duplex Fiber Optic Cables

Simplex fiber optic patch cable consists of a single strand of glass fiber, and is used for applications that only require one-way data transfer. It is commonly used where only one single transmit and receive line is desired. Simplex fiber optic patch cable is available in single mode and multimode. For instance, a single mode simplex fiber patch cable is a great option for data travelling in one direction over long distance.

Duplex fiber optic patch cable consists of two strand fibers of glass structured in a zipcord arrangement where each fiber strand has independent coatings that are linked together by a thin layer of coating material. Duplex fiber patch cable is most used where separate transmit and receive signals are required, that is, one strand transmits in one direction while the other strand transmits in the opposite direction. It is available in single mode and multimode. Multimode duplex fiber optic patch cable or single mode duplex fiber optic patch cable is usually used for applications that require simultaneous and bi-directional data transfer. For example, 10 gigabit multimode duplex cables can support 10 Gb/s bandwidth in both directions within a short distance. LC to LC duplex single mode fiber patch cable can make simultaneous data transfer with LC-LC connectors over long distance.

Conclusion

Through the above analysis, do you have a clearer understanding of simplex fiber patch cable and duplex fiber patch cable? When choosing one over the other, the key factor is that the equipment requires one-way or bi-directional data transfer. FS.COM supplies numerous types of simplex and duplex fiber optic patch cables (or fiber jumpers), such as single mode simplex fiber patch cable, LC to LC duplex single mode patch cable, 10 gigabit multimode duplex cables, LC ST duplex patch cord and so on. I believe you can always find a suitable fiber optic patch cable for your devices here.