As one of the nine Navy Manufacturing Technology's (ManTech) Centers of Excellence, the EMPF's objective is to improve the affordability and readiness of Department of the Navy systems. By working with other defense contractors, advances in manufacturing processes, techniques, and equipment can be implemented that support the fleet while ensuring reduced cost and risk.

The EMPF (in conjunction with Penn State's Electro-Optics Center and Lockheed Martin) is taking aim at reducing the costs of shipboard communications by reducing the number of cables. There are hundreds of cables and miles of cable length used to connect shipboard electronics. Most are individual connections between equipment that reside in distant locations throughout the ship. By leveraging commercial off-the-shelf (COTS) telecommunications industry fiber optics and optical wavelength division multiplexing (WDM) technology¹, a significant number of copper based Ethernet cables can be replaced by a few fiber optic cables and a fiber optic network.

Not only will this approach reduce the cost and weight of the cables, the space needed for the cables is reduced and the cable installation and maintainability is improved. Fiber optics also provides a huge increase in bandwidth and an improved immunity to electro-magnetic interference (EMI).

Of course, the insertion of any newer technology requires changes in the status quo. These are all being evaluated with an eye on affordability. Techniques for making fiber optic connections under non-ideal conditions by naval crew members are being evaluated with time studies and a variety of connection devices. By using an expanded beam connector, connections will be easier to make and less susceptible to contamination. Trade studies examining the costs of different connector techniques will help determine the most affordable approach for inserting this technology.

To minimize the number of connections and significantly reduce the size and assembly cost of the fiber optic cabling, a variety of harnesses are being evaluated. In addition to being less sensitive to environmental conditions and requiring less maintenance, the harness will provide better performance than a commercial breakout panel and require less labor to configure. A manufacturing process plan for the optical harness will be developed and prototypes constructed and evaluated.

In order to multiplex signals from a variety of equipment onto one fiber, a WDM electro-optic assembly is being developed. Typically, fiber optic components can not be exposed to as high a temperature normally seen on electronic circuit boards. They are typically hand placed and hand soldered as one of the final assembly steps. The EMPF is reducing this labor intensive effort by developing automated techniques to place and individually solder the electro-optical components using processes similar to electrical component assembly. This automation will significantly reduce assembly time and solder time while improving the reliability of the mixed technology board containing both optical and electronic components (Figure 1-1).

WDM technology allows several different signals to be simultaneously sent down one fiber-optic cable. Each signal sent down the fiber optic cable corresponds to a different wavelength or color of light. A WDM system uses a multiplexer at the transmitter to join all the signals together and a demultiplexer at the receiver to separate the signals as seen in Figure 1-2. All the Ethernet signals from one location will be combined on a single fiber, networked to an optical coupler, and combined with all the other signals from all the other locations.

This will result in a cost savings of over $1.78M per hull and could be expanded to include other digital signals that could easily be passed across the WDM fiber optic network. Other benefits include:

• Reduction of ~100 Ethernet cables (several miles of cable)
• Reduction of weight, and required cable space
• Improved cable installation, maintainability, and supportability
• Increase available bandwidth without installing additional cables
• Improved electro-magnetic interference (EMI) immunity
• Reduced manufacturing time and increased reliability of electro-optical assemblies

This effort will culminate in a proven technology providing both cost and performance benefits that can directly transition onto naval equipment and provide an off-the-shelf (OTS) path to future technology insertions. By capitalizing on the significant investment made by many DoD organizations in bringing telecommunications' industry technology to military systems, the EMPF continues to significantly deliver affordable solutions to DoD electronic systems.

Other recent EMPF affordability endeavors include:

• Flexible Antenna System for Littoral Combat Ship Phase 2
• SiGe-Based System-On-Chip Low Cost/Weight Phased Array Antennas Phases A&B
• Manufacturing of Light Activated Semiconductor Switches Phase 3
• High Voltage Encapsulation for High Power SiC Device Packaging
• Advanced Packaging Technology with Insertion into Defense Systems (APTIDS)
• Joint Strike Fighter System-on-Chip RF Tuner Manufacturing
• Power Electronic Module Cost Out for the IFTP Program

The EMPF will continue to be an active partner in the Navy's ship building affordability initiative by developing projects that reduce the acquisition costs of ship board electronics through the introduction of advanced manufacturing processes, improved electronic devices, materials, and system technologies. Expanded use of COTS, open systems, and an increased use of electronic functional integration will be applied to ship board systems resulting in substantial savings to the Navy.

For more information about the EMPF Center of Excellence and Navy ManTech Projects, contact the EMPF Helpline at 610.362.1320 or via email at helpline@aciusa.org.

Reference

• Bratt, Paul W. "Fiber Optic Wavelength-Division Multiplexing." EMPF - National Electronics Manufacturing Center of Excellence. Empfasis, Nov. 2010. Web. http://www.empf.org/empfasis/2010/November10/fiber.html