Evaluation of Optical Fiber Communication System Performance in Nigerian Telecommunications Infrastructure

Optical fiber communication systems form the backbone of Nigeria's long-haul and metropolitan telecommunications infrastructure, yet performance characterization and fault diagnostics of deployed fiber networks remain technically challenging for many Nigerian operators. This study evaluates the physical layer performance of optical fiber communication systems in three metropolitan area networks in Abuja FCT, Kaduna State, and Enugu State, North Central and South East Nigeria respectively. Optical time domain reflectometry measurements were performed on 47 fiber spans to characterize attenuation, splice loss, connector loss, and identify fault points. Bit error rate, optical signal-to-noise ratio, and chromatic dispersion penalty were measured at representative nodes in each network using calibrated optical power meters and eye diagram analysis. Measured span attenuation values averaged 0.22 dB/km for single-mode fiber at 1550 nm, consistent with ITU-T G.652 specifications, but splice losses averaged 0.14 dB per splice, exceeding the optimal 0.05 dB target. The study identifies poor field splicing practices as the primary source of excess link loss in the assessed networks. Eye diagram analysis at 10 Gbps indicates adequate signal quality with Q-factors above 10 at all tested nodes. A systematic maintenance protocol based on periodic optical time domain reflectometry surveillance and splice quality auditing is developed and costed. Professional training recommendations for Nigerian fiber optic technicians targeting splice and connector handling best practices are provided. Keywords: optical fiber, telecommunications, optical time domain reflectometry, network performance, signal quality