Modern base stations predominantly use fiber optic cables, especially for high-speed, long-distance, and high-capacity connections, though coaxial cables are still used in some legacy or short-distance setups.

Fiber Optic Cables in Base Stations

Fiber optic cables are the standard for connecting base station components due to their high bandwidth, low latency, and minimal signal loss over long distances . In modern architectures like FTTA (Fiber to the Antenna), fiber connects the Remote Radio Heads (RRHs) near the antennas to the Baseband Units (BBUs), replacing traditional coaxial feeder lines . Fiber supports both single-mode and multi-mode configurations, allowing flexible deployment for macro base stations, small cells, and C-RAN setups . It is also used in backhaul networks linking base stations to the core network and the Internet .

Coaxial Cables

Coaxial cables were traditionally used to connect antennas to base station equipment. They are suitable for short distances but suffer from higher signal loss and limited bandwidth, making them less effective for modern 4G and 5G networks . Coaxial lines are still found in some legacy installations or intra-site connections where fiber deployment is not feasible.

CPRI and Optical Interfaces

The Common Public Radio Interface (CPRI) standard often uses fiber optic cables to transport digitized radio signals between BBUs and RRHs . Fiber enables high data rates required for MIMO operations and supports flexible antenna placement, which is critical for 5G deployments . Wireless microwave links can be used as an alternative for backhaul, but they offer lower capacity and are more affected by environmental factors .

Summary

• Primary cabling: Fiber optic cables for high-speed, long-distance, and high-capacity connections.
• Legacy or short-distance cabling: Coaxial cables may still be used.
• Key technologies: FTTA, CPRI, and optical backhaul rely on fiber for modern 4G/5G networks.
• Advantages of fiber: Higher bandwidth, lower latency, reduced signal loss, and support for centralized and flexible network layouts . In conclusion, while coaxial cables exist in older or limited setups, fiber optic cables are the dominant choice for connecting base station components and ensuring high-performance mobile network operation.