Butterfly-shaped optical cable for access network

Butterfly-shaped optical cables are flat, wing-profiled fiber optic cables designed for efficient, bend-insensitive deployment in access networks, including FTTH and indoor installations.

Design and Structure

Butterfly-shaped optical cables feature a flat, wing-like cross-section with the optical fiber positioned at the center and two parallel strength members on either side, typically made of Fiber Reinforced Plastic (FRP) for durability and flexibility . This design minimizes stress on the fiber when bent in the flat plane, while edge-on bending requires more force, reducing accidental kinks during installation . The cable is usually sheathed in Low Smoke Zero Halogen (LSZH) material for safety and environmental compliance .

Fiber Type

These cables almost universally use bend-insensitive single-mode fibers, conforming to ITU-T G.657 standards. For most residential and light commercial deployments, G.657.A1 is preferred, tolerating 10 mm bend radii and fully compatible with legacy G.652.D fibers. G.657.A2 is recommended for routing through conduits with sharp bends or irregular surfaces .

Variants

• Indoor Butterfly Cables (GJXH): Lightweight, flexible, and designed for internal building distribution. Fiber counts range from 1–4 cores for single-unit residential use, up to 12 cores for multi-tenant buildings .
• Self-Supporting Outdoor Butterfly Cables (GJXFH/GJYXFCH): Include a steel messenger wire for aerial deployment, allowing spans up to 50 meters without external support. These cables combine FRP strength members with steel for tensile performance and compression resistance .

Applications

• FTTH Networks: Direct fiber connections from distribution points to homes or apartments, supporting high-speed internet, TV, and voice services .
• Indoor Cabling: Ideal for multi-story buildings, riser spaces, walls, or conduits due to compact, lightweight, and bend-resistant design .
• Data Centers and FTTX: Suitable for high-bandwidth, large-capacity data transmission while maintaining stability and reliability .

Installation and Maintenance

Butterfly-shaped cables are easy to strip and splice, supporting both fusion splicing (low-loss permanent connections) and mechanical splicing (temporary or field connections). Their flat profile simplifies routing along walls, door frames, and conduits, reducing installation complexity .

Advantages

• Bend-insensitive: Reduces signal loss in tight spaces.
• Lightweight and flexible: Simplifies indoor routing.
• Electromagnetic immunity: Non-metallic FRP members prevent interference.
• Safety: LSZH sheath ensures flame retardancy and environmental compliance.
• Self-supporting options: Steel messenger wire allows aerial deployment without additional support . Butterfly-shaped optical cables provide a practical, reliable solution for the last segment of access networks, combining mechanical strength, bend resistance, and ease of installation for both indoor and aerial applications.