Brief introduction of four kinds of connectors of optical fiber jumpers

Optical fiber jumpers (also known as optical fiber connectors) refer to the connector plugs installed on both ends of the optical cable to realize the active connection of the optical path; the plugs on one end are called pigtails.

Optical fiber jumpers (also known as optical fiber connectors), that is, optical fiber connectors connected to optical modules, also have many kinds, and they cannot be used with each other. SFP modules (SFP (Small Form-factor Pluggables) can be simply understood as an upgraded version of GBIC. SFP modules (half the volume of GBIC modules) can be configured with more than double the number of ports on the same panel. The function is basically the same as that of GBIC. Therefore, it is also called Mini-GBIC (Mini-GBIC) by some switch manufacturers.

SFP modules further compress size and power consumption by placing CDR and electrical dispersion compensation outside the module.

Google is currently buying SPF+ modules in bulk to design and manufacture its own 10 Gigabit Ethernet switches to run its data center database systems.

Fiber Patch Cord Connector

Connect to LC fiber optic connector, while GBIC connects to SC fiber optic connector. The following is a detailed description of several commonly used optical fiber connectors in network engineering:

①FC type optical fiber jumper: The external strengthening method is a metal sleeve, and the fastening method is a turnbuckle. Generally used on the ODF side (the most used on the patch panel)

②SC type optical fiber jumper: the connector connecting the GBIC optical module, its shell is rectangular, and the fastening method is the plug-and-pull type, which does not need to be rotated. (Most used on router switches)

③ST-type optical fiber jumper: commonly used in optical fiber distribution frame, the outer shell is round, and the fastening method is turnbuckle. (For 10Base-F connections, the connectors are usually ST type. Often used in fiber optic distribution frames)

④LC-type fiber jumper: a connector for connecting SFP modules, it is made with a modular jack (RJ) latch mechanism that is easy to operate. (commonly used by routers)

⑤MT-RJ type optical fiber jumper: a square optical fiber connector with integrated transceiver, one dual-fiber transceiver integrated

ST, SC connector joints are often used in general networks. After the ST head is inserted, it is fixed with a bayonet in half a circle, but the disadvantage is that it is easy to break; the SC connector is directly inserted and unplugged, which is very convenient to use, but the disadvantage is that it is easy to fall out; It is reliable and dust-proof, but the disadvantage is that the installation time is slightly longer. MTRJ type fiber optic patch cord consists of two high-precision plastic molded connectors and fiber optic cables. The outer parts of the connector are precision plastic parts, including a push-pull plug-in clamping mechanism. Suitable for indoor applications in telecommunication and data network systems.

Optical fiber modules: generally support hot swap, the optical fiber interface used by GBIC is mostly SC or ST type; SFP, namely: small package GBIC, the optical fiber used is LC type.

Fiber used:

Single mode: L wavelength 1310 single mode long distance LH wavelength 1310, 1550

Multimode: SM wavelength 850

SX/LH means single mode or multimode fiber can be used

In the label indicating the pigtail connector, we often see "FC/PC", "SC/PC", etc., the meanings are as follows

1 The front part of "/" indicates the connector type of the pigtail

The "SC" joint is a standard square joint, made of engineering plastics, which has the advantages of high temperature resistance and not easy to be oxidized. The optical interface on the side of the transmission equipment generally uses the SC connector

The "LC" connector is similar in shape to the SC connector and is smaller than the SC connector.

The "FC" connector is a metal connector, which is generally used on the ODF side. The metal connector can be plugged more frequently than plastic.

There are many varieties of connectors. In addition to the three types described above, there are MTRJ, ST, MU, etc.

2. The back of '/' indicates the cross-section process of the optical fiber connector, that is, the grinding method

"PC" is most widely used in telecom operators' equipment, and its connector section is flat.

The attenuation of "UPC" is smaller than that of "PC". It is generally used for equipment with special needs. Some foreign manufacturers use FC/UPC for the internal jumper of ODF racks, mainly to improve the indicators of the ODF equipment itself.

In addition, the "APC" model is more widely used in radio and television and early CATV. Its pigtail head adopts an end face with an inclination angle, which can improve the quality of the TV signal. The main reason is that the TV signal is analog light modulation. When the connector is coupled When the face is vertical, the reflected light returns along the original path.

Due to the uneven distribution of the refractive index of the fiber, it will return to the coupling surface again. At this time, although the energy is small, the noise cannot be completely eliminated by the analog signal, so it is equivalent to superimposing a weak signal with time delay on the original clear signal. The performance on the screen is ghosting. The inclination of the pigtail headband prevents the reflected light from returning along the original path. General digital signals generally do not have this problem.

Scope of use:

A: Optical fiber communication system

B: Optical fiber broadband access network

C: Optical fiber CATV

D: local area network LAN

E: Optical fiber instrument table

F: Fiber Optic Sensor

G: Optical fiber teaching data transmission system

H: Test equipment

fiber optic connector

FC round with thread (most used on patch panels)

ST snap-on round

SC card connection type (the most used on router switches)

PC microsphere grinding and polishing

APC is at an 8-degree angle and is ground and polished with microspheres

MT-RJ square, one dual-fiber transceiver (useful for Huawei 8850)

In the label indicating the pigtail connector, we often see "FC/PC", "SC/PC", etc., the meanings are as follows

The front part of "/" indicates the connector model of the pigtail

The "SC" joint is a standard square joint, made of engineering plastics, which has the advantages of high temperature resistance and not easy to be oxidized. The optical interface on the side of the transmission equipment generally uses the SC connector

The "LC" connector is similar in shape to the SC connector and is smaller than the SC connector.

The "FC" connector is a metal connector, which is generally used on the ODF side. The metal connector can be plugged more frequently than plastic.