What single-mode optical cables are actually used for transmission is the intermediate core, called optical fiber.
That is, single-mode optical cable is composed of optical fiber + outer sheath + intermediate medium.
In fiber optic communications, single-mode fiber (SMF) is an optical fiber that directly transmits optical signals in a transverse mode.
Single-mode optical fiber runs at a data rate of 100M/s or 1G/s, and the transmission distance can reach at least 5 kilometers.
Single-mode fiber: The central glass core is very thin (the core diameter is generally 9 or 10 μm) and can only transmit one mode of fiber.
Therefore, its inter-mode dispersion is very small and is suitable for long-distance communications, but there are still material dispersions and waveguide dispersions. In this way, single-mode optical fiber has higher requirements for the spectral width and stability of the light source, that is, The spectrum width should be narrow and the stability should be good.
Multimode optical cable is mainly used for short-distance optical fiber communications, such as Inside a building or on campus.The typical transmission speed is 100M/s, the transmission distance can reach 2km, 1G/s can reach 1000m, and 10G/s can reach 550m.
There are two types of refractive index: gradient index and step index.
Based on the distribution of refractive index, it is divided into mutation type and gradual type.
Since there are hundreds of modes transmitted in multi-mode optical fiber, the propagation constant and group rate of each mode are different, which makes the optical fiber have narrow bandwidth, large dispersion and large loss, and is only suitable for medium and short distances. and low-capacity fiber optic communications systems.
Model: GYFTY and GYFTZY are generally multi-mode; GYXTW and GYTS are generally single-mode.
