Simplex and Duplex Fiber Optic Patch Cable Overview

It is generally known that fiber optic patch cable can be classified by transmission medium (single mode or multimode), by connector construction (FC, LC etc) and by fiber cable structure (simplex or duplex). 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.

Definition of Simplex

Simplex communication is a communication channel that sends information in one direction only (see Figure 1). For instance, in TV and radio broadcasting, information flows only from the transmitter site to multiple receivers.

simplex transmission
Figure 1
Definition of Duplex

Duplex communication system is a point-to-point system composed of two connected parties or devices that can communicate with each other in both directions. It has two clearly defined paths and each path could carry information in only one direction (A to B over one path, and B to A over the other). Duplex communication system can be classified into half-duplex and full duplex. In a half-duplex system, there are still two clearly defined paths/channels, and each party can communicate with the other but not simultaneously (see Figure 2). Typically, once a party begins receiving a signal, it must wait for the transmitter to stop transmitting, before replying. A walkie-talkie is a half-duplex communication system. In a full duplex system, both parties can communicate with each other simultaneously (see Figure 3), such as a telephone.

half duplex transmission
Figure 2
full duplex transmission
Figure 3
Simplex Fiber Optic Patch Cable

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 (see Figure 4) is a great option for data travelling in one direction over long distance.

LC-LC simplex single mode fiber patch cable
Figure 4
Duplex Fiber Optic Patch Cable

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 (see Figure 5) can make simultaneous data transfer with LC-LC connectors over long distance.

LC-LC duplex single mode fiber patch cable
Figure 5

After reading the above statements, do you have a brief 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. Fiberstore has large numbers of simplex and duplex fiber optic patch cables, 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 find a suitable fiber optic patch cable for your devices in Fiberstore.

Introduction to Fiber Optic Patch Cable


Fiber optic patch cable, also known as fiber optic patch cord or fiber jumper cable, is a fiber optic cable terminated with fiber optic connectors on both ends. It is characterized by low insertion loss and high return loss, good repeatability and good interchange as well as excellent environmental adaptability. Fiber patch cables are mainly applied in two areas: computer work station to outlet and fiber optic patch panels or optical cross connect distribution center.


Generally, fiber optic patch cables are classified by fiber cable mode, fiber cable structure and connector types etc. According to fiber cable mode, fiber patch cable could be simply divided into single mode patch cable and multimode patch cable. Single mode patch cable is usually yellow with a blue connector and has a longer transmission distance. While the multimode patch cable is orange or grey with a cream or black connector and has a shorter transmission distance.

single mode and multimode patch cable

Single mode (yellow one) and multimode (orange one) fiber patch cable

By fiber cable structure, fiber optic patch cable could be classified into simplex fiber optic patch cable and duplex fiber optic patch cable. Simplex patch cable has only one fiber and one connector on both ends. However, the duplex patch cable has two fibers and two connectors on each end. Each fiber is marked “A” or “B” or different colored connector boots are used to mark polarity.

Connector design standards include FC, SC, ST, LC, MTRJ, MPO, MU, SMA, FDDI, E2000, DIN4, and D4. The commonly used fiber patch cable types include FC fiber patch cable, SC fiber patch cable, ST fiber patch cable and LC fiber patch cable. If the fiber patch cable has the same type of connector on both ends, it would be called same connector type fiber patch cable. For example, LC to LC fiber patch cable is same connector type fiber patch cable. On the contrary, if the fiber patch cable has different connectors on each end, it would be called hybrid fiber optic patch cable. For instance, LC to ST fiber patch cable is hybrid fiber optic patch cable.


When using fiber patch cable, we should pay attention to some details.

  1. Choose the right cable with right connectors according to your equipment.
  2. Protect the fiber patch cable with dust caps as dust or grease contamination will damage the fiber optic connectors and cause reflect and refract loss.
  3. Don’t excessively bend the fiber optic patch cable, or it will increase the attenuation for transmission signal.
  4. When working with fiber patch cords, pay attention to the core diameter. A large attenuation penalty will occur when using 62.5 micron multimode cords in a 50 micron cabling plant, and vice versa.

By reading the above description, hope you have a basic understanding of fiber optic patch cables and know their application principles. If you are looking for fiber patch cables, Fiberstore is a primary option. Fiberstore has various of single and multimode patch cables, including multimode SC patch cable, single mode LC to ST fiber patch cable, LC to LC fiber patch cable etc. For more information, please visit Fiberstore.

Fiber Optic Access Network Will Be The Main Force Of Internet Information Highway In The Future

As with the rapid development of social information, fiber optic technology and devices which are dedicated to provide transfer of a new business for WAN and fiber optic access network. Developments of MSTP and PON are the most representative. They are also the best solution to provide various new business in the MAN and fiber optic access network which are based on fiber optic transmission technology. As water to the fish, the developments of fiber optic access technology can not without the support and development of fiber optic access devices.

Due to the constantly updated fiber optic access technology and more and more manufacturers’ accession, nowadays the fiber optic access devices categories are more and more obvious, mainly divided into three categories:

  • Fiber optic connection elements, it is applied into telecommunications and computer network terminal connections, related product: Fiber optic patch cable, fiber optic connector and so on.
  • Fiber optic transceiver, it is utilized for computer network data transmission, related products: Fiber optic splitter, fiber patch panels and so on.
  • Fiber optic engineer devices and fiber optic testers, it is specially for large-scale project, related products: Fiber optic fusion splicer, fiber optic testers.

Next we will introduce these three fiber optic access devices with a representative products respectively, they are fiber patch cables, fiber optic splitter, fiber optic fusion splicer.

Fiber optic patch cable (shown as the figure)is fiber optic cable or fiber optical unit which without fiber optic connector, it is used in fiber distribution frames on various link roads. Fiber patch cables are also used in long distance local optical network, data transmission and private network, various testing and control system.

Fiber optic splitter (shown as the figure), someone calls it as fiber coupler, it belongs to optical passive components, it is used in the telecommunications networks, fiber cable television networks, subscriber loop system. Fiber optic splitters can be divided into standard coupler (double branch, unit 1 x 2, that is, the light signal into two power, for example, 1×2 fiber optic splitter, 1 x4 fiber optic splitter, 1 x 8 fiber optic splitter and so on), star/tree fiber splitters and wavelength division multiplexer (WDM, if the wavelength is a high-density separation and wavelength spacing is narrow, it belongs DWDM).

Fiber optic fusion splicer(shown as the figure) is mainly used in telecommunication for fiber optic cables construction and maintenance, it is applied into telecommunication operators, engineering companies, private network, also used in the production of optical passive and active devices and fiber optical modules for fiber splicing.

All above the fiber optic access devices highly improve the data transmission and processing capabilities of fiber optic access network, and at the same time they can bring two advantages:

First, it solved the long distance transmission problems of fiber line attachment,and made its coverage range more widely. In this way, then it can reduce the number of transit nodes through whole the coverage network, make the structure of the network easier.

Second, it satisfied people’s needs to various broadband business, and improve the quality of new business data. It solved the problem of traditional copper cable access network fundamentally and laid a good foundation for achieving the dream of FTTH. I believe that in the future, fiber optic access network will be the main force of internet information highway.

New Application of Fiber Optic Connector Assembly at the Scene

Recent years, PON technology has been more widely used in the fiber optic industry because of its advantages on building cost, protection cost and the broad width. And in China, the three major telecom operators – China telecom, China unicom and China mobile all bring the EPON and GPON into the telecommunication network, at the same time, in order to support the application of PON technology, ODN network is built strongly, then it put forward higher requirements to fiber optic connection, protection as well as the application and management of fiber cable devices, the most obvious device among them is fiber optic patch cable.

We all know that tradition fiber patch cables are made to follow as the certain length of fiber optic connector assembly process, different lengths of fiber cables and connectors composed of a wide variety of fiber patch cords, they can be used in fiber optic patch panels, fiber transfer boxes, fiber cable devices and the connection between the devices and other optical ports, but just because these different fiber patch cables, it bring heavy pressure to storage management. Except this, traditional factory custom the length of fiber patch cables usually more than the actual length if the route and it leaves the length of the excess in a small disk space, we can see from the figure that not only it adds the cost of distribution frame and other cable devices but also not easy to manage, and too longer fiber cables always happens intertwined, knotted squeeze and circumstances, then result in unnecessary trouble, increase the cost of maintenance and management.

longer cable

Therefore, how to control the length of fiber patch cables effectively, to avoid all the trouble. To solve the problem, Fiberstore makes his opinion. we use the on site assembly of fiber connectors, and on the 2 mm or 3 mm fiber pigtail?into end and make fiber patch cable at the scene, replacing the traditional custom factory fiber patch cables, it can greatly alleviate the traditional fiber patch cables left too long, difficulties of managements, frequent failure those a series of maintenance problems. Fiberstore comes with the close communication with all the operators and joint efforts, apply the fiber optic connector assembly of FTTH at the secne into fiber patch cables managements of fiber equipments.

After the constant experiments and used for many time successfully, we have to believe that the embedded optical fiber types of fiber optical connector assembly at the scene will be the first choice for the fiber distribution frame, cable box, optical distribution boxes and other cable device in the future, it also can give ODN network cabling system maintenance and management to bring a revolutionary change.