The difference between single-mode cable and multi-mode cable

Single-mode optical cable is actually used for transmission is the middle fiber core, called optical fiber. That is, the single-mode optical cable is composed of optical fiber + outer sheath + intermediate medium. In optical fiber communication, single-mode optical fiber (SMF) is a kind of optical fiber that directly transmits optical signals in the lateral mode. Single-mode fiber runs at a data rate of 100 M/s or 1 G / s, and the transmission distance can reach at least 5 km.

Single-mode optical fiber: the central glass core is very thin (the core diameter is generally 9 or 10 μ m), only one mode of optical fiber. Therefore, the inter-mode dispersion is very small, suitable for remote communication, but there are still material dispersion and waveguide dispersion, so the single mode fiber has high requirements on the spectral width and stability of the light source, that is, the spectral width is narrow and the stability is good.

Multi-mode optical cable is mainly used for short-distance optical fiber communication, such as in buildings or on campus. The typical transmission speed is 100 M/s, with a transmission distance of up to 2km, 1000m for 1 G / s, and 550m for 10 G / s. There are two types of refractive index: gradient refractive index and step refractive index.

Multi-mode fiber: transmitting fiber of multiple modes at a given working wavelength.

According to the distribution of their refractive index, they are divided into mutant and gradient types. Because there are hundreds of transmission modes in multimode optical fiber, the propagation constant and group rate of each mode are different, so that the band width of optical fiber is narrow, large dispersion and loss is large, which is only suitable for short and medium distance and optical fiber communication system with small capacity.

The distinction between single-mode optical cable and multi-mode optical cable?

Model: GYFTY and GYFTZY are generally multi-mode; GYXTW and GYTS are generally single-mode.

Color: indoor multi-mode optical cable is orange, indoor single-mode optical cable is yellow.

Identification: MM is multi-mode, SM is single mode.

Transmission mode: distinguish according to the transmission mode of the light in the optical fiber.