The transmission distance of optical transceiver can be divided into short-distance (within 2km), medium-distance (10-20km), and long-distance (more than 30km).
With the continuous development and upgrading of networks, the transmission distance has been extended to hundreds of kilometers. However, the optical signal would be weak during long-distance transmission. Thus many optical devices are used to solve the problem.
What would limit the transmission distance of an optic fiber transceiver? —The main factors are light source, dispersion and loss.
①Light source: generally uses an LED (light emitting diode) or a laser diode whose quality will directly affect the transmission distance of the optical signal. The laser diode can only transmit at a short distance and low rate while FD-LD laser or DFB-LD laser is generally used as the light source for medium and long distance transmission.
②Dispersion: the main reason for the dispersion is that the speed of the optical signals of different frequencies is different during the transmission, so that the time to reach the receiving end is different, which leads to the broadening of the pulse and the inability to distinguish the signal value.
③ Loss: It's the light energy loss due to the absorption, scattering and leakage of the medium during transmission. The energy is dissipated at a certain rate as the transmission distance increases.
There are many factors that affect the transmission distance of optical transceivers but they are the three most important factors. We believe that these problems will be solved with the development of technology of China transceiver and the transmission distance of optical transeivers will be longer and farther.