Submarine Optical Add Drop Multiplexer in Universal Joint
Solution Overview
Problem
Existing submarine optical communication systems face challenges in maintaining reliability and flexibility due to complex branching units, which require difficult marine operations for maintenance and have fixed wavelength allocations, limiting adaptability to changing traffic demands.
Innovation Solution
Incorporating an optical add/drop multiplexer within a universal joint, allowing for a compact, reliable, and flexible deployment of submarine optical cable joints with free space implementation, reducing the need for complex fiber splices and enabling easier maintenance by housing the multiplexer in a common component assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If branching units are made highly reliable by simplifying their structure, then maintenance becomes easier, but flexibility in spectral allocation is reduced
Solution Approach 1:
The system is divided into two functional segments: a simplified branching unit for reliable cable connections and a separate filter unit for spectral management. The branching unit handles physical connectivity with minimal complexity, while the filter unit (containing wavelength selective filters) handles spectral allocation flexibility. This segmentation allows each component to be optimized independently - the branching unit for reliability and the filter unit for adaptability.
Solution Approach 2:
The filter unit acts as an intermediary between the branching unit and the optical network. It mediates the spectral allocation requirements by inserting or removing specific wavelength channels from the optical signal passing through the branching unit. This intermediary function provides spectral flexibility without adding complexity to the branching unit itself, as the filters can be replaced independently through simpler marine operations.
2Reliability
If fixed wavelength filters are used in branching units, then reliability is improved and complexity is reduced, but spectral allocation flexibility is lost
Solution Approach 1:
The wavelength selective filters are extracted from the branching unit and placed in a separate, independently recoverable location. This extraction allows the branching unit to maintain its simple, reliable structure with fixed physical connections, while the filters provide the necessary spectral flexibility from a separate location that can be accessed and modified through simpler marine operations.
Solution Approach 2:
The system transitions from static fixed filters integrated into the branching unit to dynamic filters that can be independently replaced and reconfigured. The filters are positioned in a location that allows for dynamic changes in spectral allocation without requiring recovery of the entire branching unit, enabling the system to adapt to changing traffic demands while maintaining operational simplicity.
3Adaptability or versatility
If multiple branching units are deployed with unique OADM configurations, then spectral allocation flexibility is improved, but provisioning complexity and cost increase
Solution Approach 1:
The branching unit is designed as a universal platform that can serve multiple locations and functions with the same physical hardware. By separating the spectral allocation function into independently configurable filter units, the same branching unit infrastructure can support different OADM configurations at different locations. This universality reduces provisioning complexity and cost, as the branching units themselves can be standardized while the filters provide the necessary location-specific spectral flexibility.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution simplifies the deployment and maintenance of subsea optical networks, enhances reliability, and provides flexibility in spectral allocation, reducing the complexity and cost associated with maintaining branching units while allowing for efficient traffic management across multiple locations.
Implementation Method 1
wavelength selective filters are used to divert (drop) only the second range of wavelengths to the third location from the first location
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A common component assembly (10) is provided, for a cable joint for joining a first submarine optical cable and a second submarine optical cable. The assembly comprises: a first end face (71) comprising a first opening (73) and a first flange (72) for connection to a first cable termination unit (12) of an undersea optical cable joint; a second end face (81) comprising a second opening (83) and a second flange (82) for connection to a second cable termination unit (12) of an undersea optical cable joint; a fibre tray (85) connecting the first end face (71) to the second end face (81); and an optical assembly (185) connected to a first side of the fibre tray (85), the optical assembly (185) comprising a free space optical add/drop multiplexer.