When choosing the appropriate specification of optical fiber cable based on the transmission distance, it is necessary to comprehensively consider the type, performance and actual application requirements of the optical fiber. The following are suggestions for choosing optical fiber cables based on the transmission distance:
Optical fibers are mainly divided into two types: single-mode optical fibers and multi-mode optical fibers, and their transmission characteristics are different:
Single-mode optical fiber
Features: The core diameter is relatively small (typically 9 microns), and it can only transmit one mode of optical signal. Therefore, the intermode dispersion is small, the transmission distance is long, and the bandwidth is high.
Applicable scenarios: It is suitable for long-distance and high-speed communication transmission, such as intercity optical cables, submarine optical cables, core networks of data centers, etc.
Multimode optical fiber
Features: The core diameter is relatively large (usually 50 microns or 62.5 microns), capable of transmitting multiple modes of optical signals, but the intermode dispersion is relatively large, and the transmission distance and bandwidth are relatively limited.
Applicable scenarios: It is suitable for short-distance and low-rate communication transmission, such as within buildings, local area networks, data center access layers, etc.
Short-distance transmission (usually less than 2 kilometers) :
Recommended choice: Multimode optical fiber.
The reason is that multimode optical fibers have a relatively low cost, are easy to install and maintain, and can meet the requirements of short-distance transmission. In short distances, the transmission loss and dispersion of multimode optical fibers have a relatively small impact on signal quality.
Medium and long-distance transmission (2 kilometers to tens of kilometers) :
Recommended choice: Select single-mode or multi-mode optical fiber based on specific needs, but single-mode optical fiber is more commonly used.
Analysis:
Multimode optical fiber: Under specific conditions (such as using new multimode optical fibers and optimized optical transceivers), medium and long-distance transmission can be achieved, but the transmission distance and bandwidth are relatively limited.
Single-mode optical fiber: Due to its low loss and high bandwidth characteristics, it is more suitable for medium and long-distance transmission. At wavelengths of 1310nm or 1550nm, the transmission distance of single-mode optical fibers can reach tens of kilometers or even longer.
Long-distance transmission (tens of kilometers or more) :
Recommended choice: Single-mode optical fiber.
The reason is that the transmission loss of single-mode optical fibers is extremely low. At a wavelength of 1550nm, with the use of advanced amplifiers and dispersion compensation technology, transmission distances of hundreds or even thousands of kilometers can be achieved.
Bandwidth requirements: In addition to the transmission distance, bandwidth requirements also need to be taken into consideration. For high-bandwidth application scenarios (such as high-definition video transmission, big data processing, etc.), single-mode optical fibers should be given priority.
Cost budget: Under the premise of meeting the transmission requirements and bandwidth requirements, the cost factor should be fully considered. Multimode optical fibers have relatively low costs and are suitable for application scenarios with limited budgets.
Future scalability: When choosing the specifications of optical fibers, future scalability should also be taken into consideration. With the continuous growth of network bandwidth demands, choosing optical fiber specifications with higher bandwidth and longer transmission distance potential can facilitate future network upgrades and expansions.
For the internal connections of the data center:
For short distances: 50/125 microns or 62.5/125 microns multimode optical fibers can be selected.
For medium and long distances: If the data center is large in scale, the connection between core networks needs to be considered, and single-mode optical fiber can be selected.
For metropolitan area network or wide area network connections:
It is recommended to choose single-mode optical fiber to meet the transmission requirements of long distances and high bandwidth.
For special application scenarios:
For instance, in submarine optical cables, aerospace, etc., it is necessary to select optical fiber cables with special properties, such as high voltage resistance, low temperature resistance, and radiation resistance.
In conclusion, when choosing optical fiber cables, a comprehensive consideration should be made based on specific transmission distances, bandwidth requirements, cost budgets, and future expandability, among other factors, to select the most suitable optical fiber specification.
