There is a close relationship between the working wavelength and transmission distance of the optical transceiver module. The following introduces it to you from different aspects:
Wavelength and fiber loss characteristics: Optical fiber has different loss characteristics for light of different wavelengths. In optical communication, commonly used wavelengths are 850nm, 1310nm and 1550nm. Among them, the loss of light with a wavelength of 850nm is relatively large when it is transmitted in multimode optical fiber, and it is generally suitable for short-distance transmission, such as a few hundred meters. However, the loss of light with a wavelength of 1310nm and 1550nm is small in single-mode optical fiber, and it can achieve long-distance transmission, which makes them common wavelengths for long-distance communication.
The impact of dispersion on transmission distance: Dispersion is another important factor affecting the transmission distance of optical signals. When light of different wavelengths is transmitted in optical fiber, the degree of dispersion is different. The dispersion coefficient of light with a wavelength of 1310nm in ordinary single-mode optical fiber is small, and the signal is not easily distorted during transmission, so it can be transmitted over a long distance, generally up to tens of kilometers. In contrast, although the 1550nm wavelength light has more advantages in terms of loss, the dispersion in ordinary single-mode optical fiber is larger. If dispersion compensation is not performed, its transmission distance will be limited to a certain extent.
Correspondence between wavelength and transmission distance: Generally speaking, in multimode optical fiber, the transmission distance of the 850nm wavelength optical transceiver module is usually within 2km, which is suitable for short-distance communication scenarios such as local area networks. For single-mode optical fiber, the 1310nm wavelength optical transceiver module can achieve a transmission distance of about 10km to 40km, which is often used for medium-distance communications such as metropolitan area networks. After the 1550nm wavelength optical transceiver module is processed by dispersion compensation and other technologies, the transmission distance can reach 80km or even farther, which is suitable for long-distance backbone network communications.
Special applications and wavelength selection: In some special application scenarios, such as high-speed, large-capacity optical communication systems, in order to achieve longer transmission distances and higher transmission efficiency, specific wavelength combinations and advanced modulation technologies will be selected. For example, in a wavelength division multiplexing (WDM) system, multiple optical signals of different wavelengths are simultaneously transmitted in the same optical fiber. Ultra-long distance and ultra-large capacity communication can be achieved by precisely controlling parameters such as wavelength and dispersion.
Impact of optical device performance: The performance of the optical transmitter and receiver in the optical transceiver module will also affect the relationship between wavelength and transmission distance. High-performance optical devices can achieve higher optical power output and more sensitive optical signal reception at a specific wavelength, thereby extending the transmission distance.
Effect of environmental factors: Factors such as ambient temperature and humidity will also affect the working wavelength and transmission distance of the optical transceiver module. Temperature changes may cause the refractive index of the optical fiber to change, which in turn affects the transmission loss and dispersion characteristics of the light. In practical applications, it is necessary to select the appropriate wavelength and optical transceiver module according to environmental conditions, and take corresponding temperature compensation and other measures to ensure the stable operation of the communication system.
Future development trend: With the continuous development of optical communication technology, people are constantly exploring new wavelength ranges and more advanced optical transmission technologies to meet the growing communication needs. For example, optical communication technology in the terahertz band has higher frequency and greater bandwidth potential, and is expected to achieve ultra-high-speed and ultra-long-distance optical transmission.
