In fiber-to-the-home (FTTH) network construction, optical splitters, as core components of passive optical networks (PONs), enable multi-user sharing of a single fiber through optical power distribution, directly impacting network performance and user experience. This article systematically analyzes key technologies in FTTH planning from four perspectives: optical splitter technology selection, network architecture design, splitting ratio optimization, and future trends.
Optical Splitter Selection: PLC and FBT Technology Comparison
1. Planar Lightwave Circuit (PLC) Splitter:
•Full-band support (1260–1650 nm), suitable for multi-wavelength systems;
•Supports high-order splitting (e.g., 1×64), insertion loss ≤17 dB;
•High temperature stability (-40°C to 85°C fluctuation <0.5 dB);
•Miniature packaging, though initial costs are relatively high.
2. Fused Biconical Taper (FBT) Splitter:
•Supports only specific wavelengths (e.g., 1310/1490 nm);
•Limited to low-order splitting (below 1×8);
•Significant loss fluctuation in high-temperature environments;
•Low cost, suitable for budget-constrained scenarios.
Selection Strategy:
In urban high-density areas (high-rise residential buildings, commercial districts), PLC splitters should be prioritised to meet high-order splitting requirements while maintaining compatibility with XGS-PON/50G PON upgrades.
For rural or low-density scenarios, FBT splitters may be selected to reduce initial deployment costs. Market forecasts indicate PLC market share will exceed 80% (LightCounting 2024), primarily due to its technological scalability advantages.
Network Architecture Design: Centralised versus Distributed Splitting
1. Centralised Tier-1 Splitter
•Topology: OLT → 1×32/1×64 splitter (deployed in equipment room/FDH) → ONT.
•Applicable scenarios: Urban CBDs, high-density residential areas.
•Advantages:
- 30% improvement in fault location efficiency;
- Single-stage loss of 17–21 dB, supporting 20 km transmission;
- Rapid capacity expansion via splitter replacement (e.g., 1×32 → 1×64).
2. Distributed Multi-Level Splitter
•Topology: OLT → 1×4 (Level 1) → 1×8 (Level 2) → ONT, serving 32 households.
•Suitable scenarios: Rural areas, mountainous regions, villa estates.
•Advantages:
- Reduces backbone fibre costs by 40%;
- Supports ring network redundancy (automatic branch fault switching);
- Adaptable to complex terrain.
Optimisation of Splitting Ratio: Balancing Transmission Distance and Bandwidth Requirements
1. User Concurrency and Bandwidth Assurance
Under XGS-PON (10G downstream) with 1×64 splitter configuration, peak bandwidth per user is approximately 156Mbps (50% concurrency rate);
High-density areas require Dynamic Bandwidth Allocation (DBA) or expanded C++ band to enhance capacity.
2. Future Upgrade Provisioning
Reserve ≥3dB optical power margin to accommodate fibre ageing;
Select PLC splitters with adjustable splitting ratios (e.g., configurable 1×32 ↔ 1×64) to avoid redundant construction.
Future Trends and Technological Innovation
PLC technology leads high-order splitting: The proliferation of 10G PON has propelled PLC splitters into mainstream adoption, supporting seamless upgrades to 50G PON.
Hybrid architecture adoption: Combining single-level splitting in urban areas with multi-level splitting in suburban zones balances coverage efficiency and cost.
Intelligent ODN technology: eODN enables remote reconfiguration of splitting ratios and fault prediction, enhancing operational intelligence.
Silicon photonics integration breakthrough: Monolithic 32-channel PLC chips reduce costs by 50%, enabling 1×128 ultra-high splitting ratios to advance all-optical smart city development.
Through tailored technology selection, flexible architectural deployment, and dynamic splitting ratio optimisation, FTTH networks can efficiently support gigabit broadband rollout and future decade-long technological evolution requirements.
Post time: Sep-04-2025