Fiber and Cable

Comparison of Technical Characteristics of Fiber and Cable

Fiber and cable, as core media for modern communications and power transmission, differ significantly in their technical principles. Fiber transmits light signals through glass or plastic fibers, offering advantages such as low attenuation (single-mode fiber can reach up to 0.2 dB/km), high bandwidth (supporting speeds exceeding 100 Gb/s), and resistance to electromagnetic interference. 

Traditional cables (such as copper cables) rely on electrical transmission and are susceptible to signal attenuation and external interference, but they offer lower costs and flexible deployment. For example, fiber optic cables excel in long-distance communications, while copper cables are more suitable for short-distance power transmission or low-speed data connections.

Application Scenarios and Industry Needs

Communications: Fiber is the preferred choice for 5G networks, data center interconnects (DCI), and submarine cables. Its single-mode fiber enables transcontinental signal transmission.

Power systems: Hybrid power cables (such as OPGW and OPLC) combine power transmission and communications functions, supporting the real-time monitoring needs of smart grids.

Industrial Manufacturing: Multimode fiber is used for factory automation equipment control, while high-temperature-resistant cables are suitable for extreme environments such as metallurgy and petroleum.

Technical Challenges and Future Trends

Despite the superior performance of optical fiber, its deployment still faces challenges such as high costs (e.g., optoelectronic conversion equipment) and fragility (e.g., prone to breakage when bent). Future development directions include:

Silicon photonics integration: Reducing the cost of optical modules and promoting fiber optic integration within data centers.

Smart cables: Embedded sensors enable real-time status monitoring and improve grid reliability.

Hybrid architecture: Optimal synergy between optical fiber and copper cables, balancing performance and cost (e.g., optoelectronic hybrid cables (GDs)).

Q&A 

Q: What is the biggest difference between optical fiber and copper cables?

A: They use different transmission media: optical fiber transmits signals while copper cables transmit signals electronically. Optimal bandwidth and interference immunity are superior in optical fiber.

Q: How do OPGW cables achieve both power and communication functions?

A: Their structure combines optical fiber units with overhead ground wires, providing both lightning protection and communication capabilities.

Q: Why is multimode fiber suitable for short-distance communications?

A: Its larger core diameter supports low-cost transmission of LED light sources, but long distances can easily lead to signal mode dispersion.

Q: How can fiber bending loss be addressed?

A: Use bend-resistant fiber designs (such as the G.657 standard) or add a buffer layer to protect the fiber core.

Q: Will fiber completely replace cable technology in the future?

A: Not in the short term. Copper cables remain irreplaceable in certain scenarios (such as PoE power supply), but the proportion of fiber will continue to increase.

(AI-generated)