4-core multimode fiber transmission capability

4-core multimode fiber can support ultra-high-speed transmission, achieving hundreds of terabits per second over long unrepeated spans using advanced modulation and OTN transceivers. Overview of 4-Core Multimode FiberA 4-core multimode fiber (MCF) consists of four independent cores within a single fiber cladding, allowing space-division multiplexing (SDM) to significantly increase total transmission capacity compared to single-core fibers. Each core can carry multiple modes of light, typically using VCSELs or LEDs for short- to medium-range applications, and is compatible with standard multimode fiber types like OM3, OM4, and OM5.

Transmission Performance

Recent field trials have demonstrated the real-time transmission of 800 Gb/s per core over a 106 km unrepeated span using commercial optical transport network (OTN) transceivers. By employing 130 Gbaud modulation and 16-array quadrature amplitude modulation (PCS-16QAM), the 4-core system achieved a total real-time capacity of 256 Tb/s across 80 wavelength channels over the C+L band. This shows that 4-core multimode fiber can support long-distance, high-capacity optical interconnections without the need for inline repeaters.

Key Factors Affecting Transmission

Core Type and Diameter: Most high-speed multimode fibers use a 50 µm core (OM3, OM4, OM5), which balances cost and bandwidth efficiency. Modal Dispersion: Advanced fibers like OM4 minimize modal dispersion, enabling higher data rates over longer distances. Modulation Format: High-order modulation formats (e.g., PCS-16QAM) increase spectral efficiency, allowing more bits per symbol.

OT

N Transceivers: Commercial OTN transceivers with optoelectronic multiple-chip module (OE-MCM) packaging enhance noise tolerance and support real-time high-speed transmission. Wavelength Division Multiplexing (WDM): Using multiple wavelengths per core further multiplies the total capacity, as demonstrated in the 256 Tb/s trial. Practical Applications4-core multimode fiber is particularly suitable for: Data centers requiring ultra-high bandwidth interconnects.

Campus networks where multiple cores can reduce fiber count while increasing capacity. Next-generation optical networks leveraging SDM to overcome single-mode fiber capacity limits.

Summary

A 4-core multimode fiber can achieve hundreds of terabits per second using advanced modulation, WDM, and OTN transceivers. Its performance depends on the fiber type (OM3/OM4/OM5), core diameter, modal dispersion, and transceiver technology. This makes it a promising solution for high-capacity, long-distance, and unrepeated optical transmission systems.