PRODUCTS
- Aerial Bundled Cables
- Airport Cables
- Automotive Cables
- Alarm & Audio & Electronic Cables
- Belden Equivalent Cables
- Bus Cables
- Cable Glands
- Cables for Oil Industry
- Coaxial Cables
- Composite Cables
- Control Cables
- Data Cables
- Elevator Cables
- Fiber Optic Cables
- Fire Resisting Cable(Fireflix)
- Fire Retardant Cable(FIRETOX)
- Flame Retardant Cable (FIREGUARD)
- Flexible Cables
- Heat Detection Cables
- High Temperature Cables
- Highway Cables
- Industrial Cables
- Instrumentation Cables
- Marine Cable
- NEK606 Water Blocked Offshore & Marine Cables
- IEC60092 STANDARD Offshore & Marine Cables
- BS 6883&BS7917 STANDARD Offshore & Marine Cables
- UKOOA Offshore & Marine cables
- VG 95218 Navy Cables
- Mining Cables
- Airframe Wire
- Marine, OIL,GAS & Petrochemical Cables
- Power Cables
- Railway Cables
- Robotics
- Rolling Stock Cables
- Rubber & Crane Cables
- Security Cables
- Special Cables
- Spiral Cables
- Telephone Cables
- Thermocouple Cables
- BS 5308 Cable
- PAS 5308 Cable
- BS 5467 Cable
- BS 6724 Cable
- BS 6346 Cable
- BS 7211 Cable
- IEC 60502-1 Cable
HOT PRODUCTS
APPLICATIONS
|
The Differences Between Single-mode Fiber And Multi-mode Fiber
Single-mode fiber and multi-mode fiber are two main types in optical fiber communication. The core differences lie in transmission principles, structural characteristics, performance parameters, and application scenarios, which are compared as follows:
1. Differences in Transmission Principles and Structures
1. Single-mode Fiber
- Principle:
The core is extremely thin (with a diameter of about 8-10μm, close to the wavelength of light), allowing only a single mode of light signal (fundamental mode) to travel in a straight line. This avoids modal dispersion (signal distortion) caused by differences in the propagation paths of different light modes. - Structural Features:
- Core: High-purity silica (with minimal doping) and high refractive index;
- Cladding: Lower refractive index than the core to form total reflection conditions;
- Advantage: Stable transmission and no modal dispersion, suitable for long-distance and high-speed transmission.
2. Multi-mode Fiber
- Principle:
The core is thicker (commonly 50μm or 62.5μm), allowing multiple modes of light signals to transmit simultaneously. However, different light modes have different path lengths, causing modal dispersion and leading to signal attenuation with distance. - Structural Features:
- Core: Doped with more substances (such as germanium and phosphorus) to increase the refractive index, with a larger diameter;
- Cladding: Functions similarly to single-mode fiber but has lower requirements for material purity;
- Limitation: Modal dispersion limits transmission distance and bandwidth.
2. Comparison of Key Performance Parameters
| Dimension | Single-mode Fiber | Multi-mode Fiber |
|---|---|---|
| Core Diameter | 8-10μm | 50μm or 62.5μm |
| Light Source Type | Laser (e.g., 1310nm/1550nm lasers) | LED or VCSEL (vertical-cavity surface-emitting laser) |
| Transmission Distance | Tens of kilometers (long-distance) | Usually ≤2 kilometers (short-distance) |
| Bandwidth Performance | Ultra-high (tens of Tbps level) | Lower (hundreds of MHz·km to several GHz·km) |
| Cost | Higher (complex manufacturing process) | Lower (simple manufacturing process) |
| Type of Dispersion | Almost no modal dispersion, mainly material dispersion | Modal dispersion dominant, limiting transmission distance |
3. Application Scenarios
1. Application Scenarios for Single-mode Fiber
- Long-distance communication: Long-haul trunks, undersea cables, backbone networks (e.g., 5G core network interconnection);
- High-speed transmission: Inter-data center interconnection, 100G/400G optical module transmission;
- Precision sensing: Fiber optic gyroscopes, distributed temperature/strain monitoring.
Typical Case: Transoceanic undersea cable systems (such as FASTER and SEA-ME-WE 6) almost entirely use single-mode fiber.
2. Application Scenarios for Multi-mode Fiber
- Short-distance interconnection: Internal rack connections in data centers, enterprise local area networks (campus networks, park networks);
- Low-cost scenarios: Industrial automation control, building integrated wiring;
- Education/medical fields: Optical communication experiments in laboratories, endoscopic image transmission.
Typical Case: In cloud computing data centers, multi-mode fiber combined with VCSEL light sources enables 10G/25G rate transmission between racks.
4. How to Choose?
- Prefer single-mode fiber: For scenarios requiring long distance (>2 km), high speed (>10 Gbps), and low latency, such as wide area networks and backbone networks.
- Prefer multi-mode fiber: For short-distance (<1 km), medium-to-low speed (<10 Gbps), and cost-sensitive scenarios, such as local area networks and internal data center connections.
- Note the matching: The light source must be consistent with the fiber mode (single-mode fiber with lasers, multi-mode fiber with LED/VCSEL).
Conclusion
Single-mode fiber relies on the core advantages of "single mode, long distance, and high speed" to serve as the "main road" for long-distance communication; multi-mode fiber is more suitable for short-distance "last mile" connections due to its characteristics of "multiple modes and low cost". The two complement each other and jointly form the cornerstone of modern optical communication networks.
