What is the combination of the fronthaul optical module

The primary function of combining fronthaul optical modules is to aggregate multiple radio services onto a single optical fiber, increasing bandwidth efficiency, reducing fiber usage, and supporting high-capacity, low-latency mobile networks.

Aggregation and Multiplexing

Fronthaul optical modules, often deployed in 5G and future 6G networks, connect Remote Radio Units (RRUs) to Baseband Units (BBUs) or Distributed Units (DUs). Combining these modules allows multiple data streams from different radio services to be multiplexed over a single fiber, significantly reducing the number of fibers required while maintaining high throughput and low latency. Technologies like Dense Wavelength Division Multiplexing (DWDM) enable each service to be transmitted on a separate wavelength, allowing up to 24 or more services per fiber strand.

Bandwidth Optimization

By combining optical modules, operators can achieve high-capacity transmission without increasing the physical fiber infrastructure. For example, using DWDM, 24 services at 25 Gbps each can be transported over a single fiber, resulting in 600 Gbps per fiber strand. This aggregation also supports mixed protocols such as CPRI, eCPRI, and Ethernet, enabling flexible and transparent transport of different service types.

Fiber Resource Efficiency

Combining fronthaul optical modules reduces the number of optical fibers needed by up to 90%, saving costs and simplifying network deployment. Single-fiber bidirectional (BiDi) modules and WDM solutions further optimize fiber usage by allowing uplink and downlink signals to share the same fiber, which is particularly valuable in dense urban deployments or areas with limited fiber availability.

Low Latency and Synchronization

Fronthaul links are highly latency-sensitive. Combining optical modules ensures that multiple services are synchronized and transmitted with minimal jitter, meeting strict timing requirements for 5G and 6G networks. Small form-factor modules like SFP28/25G or short-reach BiDi optics are commonly used to maintain precise timing and low-latency performance.

Summary

In essence, the function of combining fronthaul optical modules is to aggregate multiple radio signals efficiently, maximize fiber utilization, support high-speed and low-latency transmission, and enable scalable deployment of next-generation mobile networks. This approach is critical for meeting the growing bandwidth demands of 5G and future 6G networks while minimizing infrastructure costs and complexity.