Common Capabilities Link the Undersea Fleet
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The Common Submarine Radio Room (CSRR) system reduces the equipment footprint on a submarine through a combination of commercial technology and other novel features. |
The U.S. Navy is installing a network-based communications architecture to use bandwidth more effectively on a variety of submarines. The technology automates functions and requires less equipment and fewer personnel than current systems. The Navy recently declared the technology ready for the fleet.
The Common Submarine Radio Room (CSRR) system will modernize communications onboard Virginia-class, Ohio-class SSBN and SSGN, and Seawolf-class submarines. Unlike older technologies, the CSRR includes network-based architecture that is not baseband limited. Previous systems have 64-kilobyte-per-second limitations. The CSRR also has lower modernization costs because its open architectures are easier to upgrade, as opposed to those of closed systems, which have greater limitations. The use of “big Navy” communications solutions for commonality across all Navy platforms, as well as the system’s commonality among the various types of submarines, allows a single integration effort to implement the sea service’s modernization goals.
Commonality across the submarine platforms also lowers the cost to maintain technical documentation and results in more focused training, allowing operator experience to transfer to other submarine platforms. Additional costs are reduced through the common parts support system, which translates into larger procurements of spare parts and less inventory on the supply systems shelves. The CSRR’s automation functions enable the submarine force to support missions with significantly higher communications requirements without additional personnel.
The CSRR also supports the Navy’s portion of the Global Information Grid architecture and will support interoperability at the radio level. As the CSRR system integrates other Navy radio programs of record, the submarine force reduces non-interoperability risks resulting from unique submarine radio solutions.
One of the technologies that could integrate into the CSRR system is the Airborne, Maritime and Fixed Station Joint Tactical Radio System (AMF JTRS). Wendy Underwood, director for communications and networking with Lockheed Martin Tactical Systems, says that when AMF JTRS is available, it will fit easily into the CSRR system. Lockheed Martin developed the CSRR and is working with the Navy’s Submarine Integration Program Office, which falls under the Navy’s Program Executive Office for Command, Control, Communications, Computers and Intelligence (PEO C4I). One tenet of the PEO C4I is to use Navy programs of record. “The key is to allow the Navy to easily incorporate in programs of record updates and that sort of thing into the CSRR design,” Underwood explains.
Her colleague, John Uittenbogaard, technical director, Common Radio Room Programs, states that the precursor to JTRS, the Digital Modular Radio, is the heart of the CSRR from a radio standpoint. The software-defined, reconfigurable radio is the key to enabling an automated radio room. Uittenbogaard adds that two Cisco routers that provide interoperability with the rest of the fleet are at the core of the network-centric design, again enabling the FORCEnet connectivity. “It enables the FORCEnet-type vision of communication network centricity all the way through to the operator,” he shares. FORCEnet is the operational and architectural framework that integrates warriors, sensors, networks, command and control, platforms and weapons into a networked, distributed combat force for the future.
The various capabilities and functionalities of the CSRR system bring multiple benefits to submarines as compared to prior submarine external communications systems. One benefit is the network-based architecture that does not limit available bandwidth to 64 kilobytes per second. The flexibility of the network-based architecture enables the system to use all available bandwidth so it better meets mission requirements. According to Dan Brothers, CSRR assistant program manager, Submarine Integration Program Office, Navy PEO C4I, the SSGN could not support special operations forces missions without the CSRR system because of the high bandwidth requirements.
Other benefits include an efficient management control workstation that leverages automation of radios and overall system control. This allows a single operator to manage 30 circuits simultaneously, whereas legacy systems require an operator for every five to 10 circuits.
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The U.S. Navy’s success with the CSRR on submarines has sparked interest in using the technology on new surface ships such as the littoral combat ship and to modernize older vessels. |
The software talks to each radio and each different piece of equipment in the radio room. Once operators establish communication through the software, all the tasks they are required to perform to configure a circuit are automated. Operators can graphically use the software to create circuits and then save various configurations for different missions. By doing this, they can bring up pre-set communications plans during operations, and the software automatically tunes the equipment.
The CSRR system reduces the radio room operator workload and enhances the operators ability to understand the communications picture. The automation enables operators to both configure and monitor equipment automatically. If any equipment goes down, the system will alert the operator, enhancing the communications posture of the ship. Other sailors benefit as well, such as commanders who have a better understanding of their communications. They can view their communications software status screens to know immediately what communications are available. The automation also reduces the chance of human error.
In conjunction with reducing manpower through automation, the CSRR system reduces the Navy’s total ownership costs. The CSRR offers the Navy a configuration control board for use across all subsurface platforms, giving the sea service a common baseline. It also reduces training needs.
According to Brothers, the Navy currently provides a full suite of hardware and control and management software tied to simulation/stimulation hardware at the Trident training facilities in
Brothers says the biggest benefit the CSRR system offers to individual sailors is the combination of training and ease of modernization. The similarities among the various platforms and the trainers enables sailors to move among the different submarines and be ready to support systems operations almost from the day they arrive onboard. “Only the small differences between variants that are a result of different missions will have to be learned as compared to the radical differences in system architecture and operations on older submarine external communications systems,” Brothers explains. The open system architecture permits easier, less-expensive modernization so the latest communications upgrades can be deployed more quickly.
The CSRR system also reduces the equipment footprint on subsurface ships. When the CSRR was installed on a Virginia-class submarine, only nine racks of equipment were necessary. In contrast, the Los Angeles-class attack submarine requires 13 racks of communications gear. The reduction results from the use of commercial technology—which is inherently smaller than custom technology in many cases—employed in conjunction with existing programs of record to optimize the submarine’s footprint.
The use of modern, reconfigurable radios eased the equipment load as well. The computer automation software allows submarine personnel to reuse the same radios in different missions by reconfiguring them instead of having to use separate radios or different configurations for different missions. With older systems, sailors dedicated several radios to a particular type of communication, even though they might use only one of three of the radios at a given time. With the reconfigurable radios, sailors can eliminate the excess two radios by using the software to reconfigure them for each mission.
In addition to the range of missions the CSRR system can support, each platform has to communicate with varying members of the Navy. Uittenbogaard explains that two main types of communications exist: communications with other members of a battle group and communications with a shore facility. The CSRR system is interoperable with those other Navy components and can create circuits on both the secret Internet protocol router network and the nonsecure Internet protocol router network.
In terms of supportability, Brothers believes important advantages of the CSRR system are that a single integration effort will support modernization across all submarine platforms and that training and logistics supportability will be common across all platforms as well. The commonality results in higher states of fleet readiness.
The notion of common requirements harmonized across ship classes has aided developers and engineers as they work on different platforms. For example, when the Seawolf program implemented the CSRR system, the requirements for that platform were only 17 percent in common with the common baseline already developed for other submarine classes. However, when the engineers from Seawolf, PEO C4I and Lockheed Martin sat down together to resolve the issue, they found that the essence of certain requirements were the same among the various platforms. Working with that idea in mind, the commonality increased from 17 percent to 85 percent. “That’s a remarkable aspect of where the power of commonality pays off,” Underwood states. She adds that if personnel strive for commonality, they can achieve it.
The CSRR became operational as an Ohio SSGN conversion baseline system in October 2005, and the conversion baseline provided approximately 30 percent of the total SSGN baseline system capability. The CSRR system reached successful initial operational capability with completion of operational testing in September 2006. The first Seawolf CSRR system deployed on SSN-21 in summer 2006. In November 2006, the first SSGN full-baseline CSRR system was completed and became operational. Three Seawolf CSRR systems are operational; two complete SSGN systems are operational; two SSBN systems are operational; and the first full Virginia-class CSRR baseline system started testing earlier this year.
The success of implementing the CSRR system on submarines, as well as the system’s cost and supportability advantages, has led the Navy to consider installing the technology on surface vessels as well. The PEO C4I is working to place into operation a surface variant for new construction platforms, such as the littoral combat ship, and eventually to modernize older platforms. The effort is in the early planning stages.
Web Resources
Navy PEO C4I: http://enterprise.spawar.navy.mil/body.cfm?type=c&category=24&subcat=53
Lockheed Martin: www.lockheedmartin.com
AMF JTRS: http://www.lockheedmartin.com/products/AirborneMaritimeFixedStationJointTa/index.html