Is the single-mode double fiber divided into a.b end?

　　Single-mode dual fiber does not distinguish between A and B ends. The following is a detailed explanation of single-mode dual fiber:

　　First, the definition and principle

　　Definition: Single-mode dual fiber refers to the connection method that uses two fiber cores for data tranSMission in an optical fiber communication system. One fiber core is used to send data and the other fiber core is used to receive data.

　　Principle: In a single-mode dual-fiber connection, the signal at the sending end is transmitted through one fiber core, while the signal at the receiving end is returned through another fiber core, thus realizing two-way data transmission.

　　Second, the difference with single-mode single fiber

　　Single-mode single fiber: uses a single fiber core for data transmission, but requires the use of two different wavelengths of light to achieve. Therefore, there is a difference in the wavelength of the emitted light between the A terminal and the B terminal. The A terminal usually represents one wavelength combination (such as 1310nm/1550nm), and the B terminal represents another wavelength combination (such as 1550nm/1310nm). Users must ensure that the A terminal and the B terminal are paired correctly when using.

　　Single-mode dual fiber: Since two fiber cores are used for data transmission, there is no need to distinguish between A and B ends. Just connect the sending end to one fiber core and the receiving end to the other fiber core.

　　III. Application scenarios

　　Single-mode dual fiber is widely used in high-performance network communication scenarios such as long-distance communication and data center interconnection due to its long transmission distance and strong anti-interference ability.

　　In summary, single-mode dual fiber does not need to distinguish between A and B terminals, but realizes bidirectional data transmission through two fiber cores.