Detail Of Single Mode And Multi Mode Fiber Optic Cable

by Fiber-MART.COM

Fiber optic cable has become apparent that fiber-optics are steadily replacing copper wire as an appropriate means of communication signal transmission. They span the long distances between local phone systems as well as providing the backbone for many network systems. Other system users include cable television services, university campuses, office buildings, industrial plants, and electric utility companies.

 

There are three types of fiber optic cable commonly used:  single mode, multimode and plastic optical fiber (POF).  Although fibers can be made out of transparent plastic, glass, or a combination of the two, the fibers used in long-distance telecommunications applications are always glass, because of the lower optical attenuation.  Both multi-mode and single-mode fibers are used in communications, if you need to transmit less data over longer distances, use single mode fiber optic cables. For a greater data capacity over shorter distances, go with multi mode fiber optic cables, with multi-mode fiber used mostly for short distances (up to 500 m),Multi mode is often used for LANs and other small networks. And single-mode fiber used for longer distance links.

 

Single Mode Fiber: Single Path through the fiber

 

Single Mode cable is a single stand (most applications use 2 fibers) of glass fiber with a diameter of 8.3 to 10 microns that has one mode of transmission.  Single Mode Fiber with a relatively narrow diameter, through which only one mode will propagate typically 1310 or 1550nm. Carries higher bandwidth than multimode fiber, but requires a light source with a narrow spectral width.  Single Mode is also referred to as single-mode fiber, single-mode optical waveguide, mono-mode optical fiber and uni-mode fiber. Single-mode fiber gives you a higher rate of transmission, it also can carry the signal up to 50 times farther distance than multimode, at a slightly higher cost.Single-mode fiber has a much smaller core than multimode.

 

Single Mode fiber is used to connect long distance switches, central offices and SLCs (subscriber loop carriers, small switches in pedestals in subdivisions or office parks or in the basement of a larger building). Practically every telco’s network is now fiber optics except the connection to the home.

 

Multi Mode Fiber: Multiple Paths through the fiber

 

Multi-Mode cable has a little bit bigger diameter, with a common diameters in the 50-to-100 micron range for the light carry component (in the US the most common size is 62.5um).Typical multimode fiber core diameters are 50, 62.5, and 100 micrometers.  Multi Mode fiber is used for shorter distances. Most applications in which Multi-mode fiber is used, 2 fibers are used. Multimode fiber gives you high bandwidth at high speeds (10 to 100MBS – Gigabit to 275m to 2km) over medium distances. Light waves are dispersed into numerous paths, or modes, as they travel through the cable’s core typically 850 or 1300nm. Long cable runs (Above 3000 feet 914.4 meters in length), the multiple paths of light are believed to cause signal distortion at the receiving end, resulting in lost packets and incomplete data transmission. IPS recommends the use of single mode fiber in all applications using Gigabit and higher bandwidth.