Submarine Cable Networks

During construction, end face inspection can detect dirt particles or other physical defects whose impact can either diminish or halt the performance of the network (and produce bad test results). Perhaps the most essential tool for physical layer fibre verification is the OTDR. Specialized types can be used for long haul wet plant OTDR as well as versatile bidirectional dry plant OTDR.

Another parameter that must be measured and controlled during cable deployment for submarine network construction is the amount of strain being placed on the actual fibres; this must be lower than 0.34% for submarine fibre grade (IEC 60794-3-20), higher values will reduce the lifespan of the fibres. Strain measurement can be performed using portable Brillouin OTDR. Optical dispersion tools are also pivotal to the characterization of networks in order to baseline optical dispersion and assess if any dispersion compensation is required.

Service activation requires tools for optical power measurement and spectrum analysis along with data network equipment testing. In order to quantify optical power, a ruggedized optical power meter is an essential tool. High quality Optical Spectrum Analysers (OSA) for performing Optical Signal-to-Noise Ratio (OSNR) measurement and Network testers for latency, throughput, jitter, and frame loss/bit error rate analysis are also a must during this phase to validate and certify network performance.

Monitoring and maintenance are the keys to keeping the vital cable networks performing optimally. To assess the fibre’s physical health, an effective optical network monitoring system such as ONMSi can provide real-time fault, degradation, and security issue monitoring.

Fibre monitoring of links is an essential ongoing function. ONMSi can be used to detect fibre degradation and a wide array of fibre monitoring techniques may be utilized to meet the unique challenges associated with a fault. For example, to detect fluctuations in strain, temperature, and other parameters inherent to submarine cables, fibre optic sensing tools play a critical role. In addition, service performance monitoring is key to proactively identifying data issues (such as latency, throughput, jitter, and frame loss/bit error rate) and is usually required in order to prove SLA compliance for customers.