N23A-T002   TITLE: DIGITAL ENGINEERING - Integration of Fiber Optics Systems Design, Supportability, and Maintainability

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Microelectronics;Networked C3

OBJECTIVE: Develop modeling approach for designing, maintaining, and supporting air and sea platform digital and analog fiber optic communications technology.

DESCRIPTION: The use of optical fiber on air, surface ship, and undersea platforms is pervasive, and is an enabling technology. Current military electronics, electro-optic, communications, radar, and electronic warfare systems require ever-increasing bandwidths, while simultaneously demanding reductions in space, weight, and power (SWaP). The effectiveness of these systems hinges on optical communication components that realize sufficient link budget, dynamic range, and compatibility with military surface ship, undersea platform, and aircraft maintenance environments [Refs 1-5]. Future digital and analog/radio frequency (RF) signal transmission rates and frequencies have increased to the point where fiber optics is the only medium with the capacity and low loss for maintaining communications signal integrity. Maintainability and supportability are well-known operational availability drivers for fiber optics technology deployment on military platforms [Ref 6]. Key systems engineering design considerations include architecture (openness, modularity, scalability, and upgradeability), reliability, maintainability, and supportability. Supportability infrastructure is difficult to add on after the design is established, and therefore should be included in the systems engineering design process.

Key fiber optics systems engineering design considerations include architecture, reliability, maintainability, and supportability. Integrating the disparate interfaces associated with digital and analog/RF fiber optic systems, and a model-based engineering approach, requires significant digital engineering research and innovation. Although the Navy has complete knowledge of the required connections and interfaces for digital and analog/RF fiber optics, there is no model-based approach to selecting components (connectors, cable, termini, transmitters, receivers), support equipment (maintenance sets), training, and the required supportability and maintainability concepts. MIL-HDBK-217 requires modernization for fiber optics reliability engineering [Ref 7]. This digital engineering research effort should develop models that include all of the platform components, support equipment, associated fleet maintainer training, reliability data, and digital and analog/RF fiber optic system design engineering principles. Digital engineering research should capture approaches to minimize the number and diversity of parts and interfaces, and be applicable to aircraft, surface ship, and undersea platform specific model-based system-engineering models. Digital engineering research is also required to understand how to best utilize the existing CAMEO Systems Modeler tool [Ref 8] and Systems Modeling Language (SysML) [Ref 9] for ship and aircraft fiber optics hardware integration, relevant use cases, use of existing standards, digital and analog/RF link design principles, and use of existing and emerging components.

Fiber optics supportability cuts across reliability, maintainability, and the supply chain to facilitate detection, isolation, and timely repair/replacement of system anomalies. Typical supportability features include prognostics, diagnostics, skill levels, support equipment footprint, training, maintenance data collection, compatibility, packaging and handling, and other factors that contribute to an optimum environment for sustaining a fiber optic system. The ability to sustain the operation of a fiber optic system on a surface ship, undersea platform or aircraft, is established by the inherent supportability of the system and the processes used to sustain the functions and capabilities of the system in the context of the end user. The focus of sustainment planning is to influence the inherent supportability of the system and to plan the sustainment capabilities and processes used to sustain system operations. Sustainment influence requires an understanding of the system missions and mission profiles and to provide rationale for functional and performance priorities. Understanding the rationale paves the way for decisions about necessary tradeoffs between system performance, with impact on the cost effectiveness of system operation, maintenance, and logistics support. There is no single list of sustainment considerations or a specific way of grouping system operation, maintenance, and logistics support, as they are highly inter-related. They include compatibility, transportability, the actual maintenance environment, diagnostics and prognostics (including real-time maintenance data collection and built-in test), and corrosion protection and mitigation.

Fiber optics maintainability considerations encompass modularity, interoperability, physical accessibility, training, testing, and human systems integration. Maintainability generally requires balancing the maintenance requirement over the life cycle with minimal user workload. The emphasis on maintainability is to reduce the maintenance burden and supply chain by reducing time, personnel, tools, test equipment, training, facilities, and cost to maintain the system. Maintainability engineering includes the activities, methods, and practice to design minimal system maintenance requirements and associated costs for preventative and corrective maintenance, as well as servicing and calibration activities. Maintainability should be a designed-in capability and not an add-on option, because good maintenance procedures cannot overcome poor system and equipment maintainability design. The primary objective is to reduce the time and complexity for a properly trained maintainer to detect, isolate and repair a failure.

PHASE I: Collect research data on fiber optic components, link-loss power budget methodologies, system design concepts, maintenance concepts, support equipment concepts, and overall maintainability and supportability. Using SysML, create handoff between reliability, maintainability, and supportability within the bounds of the military platform fiber optic systems engineering process. Identify key risk areas for tracing lower level fiber optic system designs to higher level supportability and maintainability considerations to realize desired life cycle performance, and mitigate these risks using digital engineering research concepts and modeling tools. Demonstrate operational suitability trade-offs of model-based system engineering approaches to fiber optic system design and support. The Phase I effort shall include plans to be developed under Phase II.

PHASE II: Develop digital engineering-based prototype software to enable modeling of fiber optics integration in the context of supportability and maintainability. Optimize the model designs using representative cases from ships and aircraft. Build and test support equipment prototypes based on results from the models. Determine the efficacy of the entire support concept. Deliver the SysML model and digital engineering software.

PHASE III DUAL USE APPLICATIONS: Finalize the application. Verify and validate the application in model-based systems engineering environments that are applicable to aerospace, surface ship, and undersea platforms. Transition to applicable naval platforms.

Commercial sector telecommunication systems, fiber optic networks, and data centers could benefit from the development of this application.

REFERENCES:

1.       Binh, L. N. (2017, July 26) Advanced digital optical communications (2nd ed.). CRC Press. https://www.worldcat.org/title/advanced-digital-optical-communications/oclc/1053852857?referer=br&ht=edition

2.       Urick, V. J., Williams, K. J. & McKinney, J. D. (2015). Fundamentals of microwave photonics. John Wiley & Sons. https://www.worldcat.org/title/fundamentals-of-microwave-photonics/oclc/895388531&referer=brief_results

3.       AS-3 Fiber Optics and Applied Photonics Committee. (2018, January 23). AS5603A Digital Fiber Optic Link Loss Budget Methodology for Aerospace Platforms. Warrendale: SAE. https://www.sae.org/standards/content/as5603a/

4.       AS-3 Fiber Optics and Applied Photonics Committee. (2018, January 23). AS5750A Loss Budget Specification for Fiber Optic Links. Warrendale: SAE. https://www.sae.org/standards/content/as5750a/

5.       Naval Sea Systems Command. (1997, October 10). MIL-STD-2052A: Department of Defense design criteria standard: fiber optic systems design. Department of Defense. http://everyspec.com/MIL-STD/MIL-STD-2000-2999/MIL-STD-2052A_9141/

6.       Department of Defense. (1991, December 2). MIL-HDBK-217F: Military Handbook: Reliability prediction of electronic equipment. Department of Defense. http://everyspec.com/MIL-HDBK/MIL-HDBK-0200-0299/MIL-HDBK-217F_14591/

7.       CATIA. (n.d.). Cameo systems modeler. 3DS.com. Retrieved August 25, 2021, from https://www.nomagic.com/products/cameo-systems-modeler

8.       Defense Supply Center Columbus. (2010, May 28). MIL-STD-1678/1: Department of Defense standard practice: Fiber optic cabling systems requirements and measurements (Part 1: Design, installation and maintenance requirements). Department of Defense. http://everyspec.com/MIL-STD/MIL-STD-1600-1699/MIL-STD-1678-1_20346/

9.       The Object Management Group. (n.d.). What is SYSML? OMG Systems Modeling Language. Retrieved August 25, 2021, from https://www.omgsysml.org/what-is-sysml.htm

 

KEYWORDS: Fiber optics; system design; supportability; maintainability; model-based systems engineering; digital engineering

---