1. What are the development and advantages of the optical fiber transmission system of cable TV optical transceivers?

Answer: The transmission of TV signals and data information by light waves is a new science and technology developed at the end of the 20th century. Its appearance has made the world information industry develop rapidly. Now optical fiber transmission technology is developing at a speed beyond people's imagination. The transmission speed has increased by 100 times compared with 10 years ago, and it is estimated that it will increase by about 100 times in the future development. With the continuous development of optical fiber transmission technology, multiplexing, demultiplexing, routing, and switching can be performed in the optical domain. The network can utilize the huge bandwidth resources of optical fibers to increase network capacity and achieve "transparent" transmission of various services. .

2. What is the basic principle of optical signal transmission by cable TV optical transceiver?

Answer: Optical transmission is a technology that transmits in the form of optical signals between the sender and the receiver. The working process of optically transmitting TV signals is carried out between the optical transmitter, optical fiber and optical receiver; the optical transmitter in the central computer room converts the input RF TV signal into an optical signal, which is converted by an electrical/optical converter ( Electric-Optical Transducer, E/O) is completed, and the converted optical signal is received by the optical fiber transmission guide receiving device (optical receiver), and the optical receiver converts the optical signal obtained from the optical fiber and restores it to an electrical signal. Therefore, the basic principle of optical transmission signal is the whole process of electrical/optical and optical/electrical conversion, also known as optical link.

3. How does the optical fiber guide the transmission of optical signals?

A: The fiber used in the current cable TV system is a cylindrical fiber, which is composed of a fiber cylinder and a cladding, and is made of quartz glass. The cladding plays the role of tightly enclosing the light in the fiber, protecting the core and enhancing the strength of the fiber itself. The function of the fiber core is to transmit optical signals. Although the core and cladding are produced from quartz glass materials, the doping components of the two are different during production, resulting in different refractive indices (1.463~1.467 for the core and 1.467 for the cladding). 1.45~1.46), of course, it is also related to the different materials used. When the light source emitted by the laser enters the fiber core and the light is incident on the cladding interface, as long as the incident angle is greater than the critical angle, total reflection will be generated in the core, and the light will not leak into the cladding, so that it will be concentrated into the fiber. The optical signal in the core will propagate uninterruptedly until it is directed to the optical receiver. This process is the basis for the transmission of optical signals in optical fibers.