ABERDEEN PROVING GROUND, Md. -- GPS provides Soldiers with position, navigation and timing information; however the signal's susceptibility to interference can turn a routine mission into anything but.

In addition, each platform function, such as driver navigation, overall situational awareness or weapons targeting information requires a separate GPS receiver, creating additional size, weight and power issues inside the vehicle.

To address these concerns, the Army's Communications-Electronics Research, Development and Engineering Center has developed the Mounted PNT system, which complements the existing GPS-only capability should the signal become degraded or denied, and, as a single system, unclutters the platform in keeping with today's expeditionary missions.

"GPS signal issues occur in a variety of environments, including city buildings, forests and mountainous terrain, or from adversarial sources who employ jamming devices to degrade or completely block the signal," said Van Tran, lead engineer for Mounted PNT under CERDEC's Command, Power and Integration Directorate's Positioning, Navigation and Timing Division. "To aid GPS, we grouped an assortment of sensors based on their function and the platform's mission to form the Mounted PNT system."

Sensor options include inertials, which use accelerometers and gyroscopes to measure position orientation and velocity; radios to conduct RF ranging, which obtains distances by measuring the time it takes the signal to go from Point A to Point B; cameras to shoot and compare pictures frame by frame to determine movement, and the Chip Scale Atomic Clock, which provides very accurate time.

"No single PNT sensor will provide you with assured PNT everywhere all the time," said Rex Howe, CP&ID PNT&D senior engineer. "Each has its own specific strength and weakness, but by uniting them into a fully integrated system the result is better overall performance."

The system is adaptable and can be tailored prior to fielding to reflect mission requirements. For example, developers can replace just the GPS module or individual sensors rather than having to replace the entire system, Tran said.

"The flexible design will also seamlessly operate with the new Military Code, or M-Code, signal, which will replace the current GPS signal to help provide protection against intentional GPS interference and is a component of the Army's GPS modernization effort," Howe said.

CERDEC has been developing PNT capabilities since the 1960s and currently Direct Reporting Program Manager PNT, which is providing Assured PNT to mounted and dismounted Soldiers.

"The Army deemed Assured PNT as a critical function for mission success and Soldier safety," said Charlie Miller, chief of CP&ID's PNT&D. "We are able to leverage our organization's vast research and development expertise to develop forward-thinking PNT capabilities."

CERDEC has already shown success in addressing future Mounted PNT capabilities by developing a prototype system that consolidates multiple warfighting function systems into one mounted product. This effort known as Hardware/Software Convergence features one chassis that contains separate payload cards to address areas such as PNT, communications, electronic warfare and mission command.

"By using a chassis, the platform could alleviate space-stealing components such as transit cases, power supplies, mounts, and cabling," Howe said. "It will provide an entire PNT solution as well as a system clock that provides slot to slot synchronization to less than 80 pico seconds, or less than 80 trillionths of a second."

The system will feature an open architecture and open standards design, which will provide a competitive field to develop hardware and software updates instead of entire system builds, Howe said.

"Our innovative PNT solutions can support short-term program goals or be program-or product-agnostic when we are conceptualizing future innovations," Miller said. "In either instance, we believe our R&D efforts will lead to robust Assured PNT solutions that support many Army warfighting functions and the Soldiers who rely on them."

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The U.S. Army Communications-Electronics Research, Development and Engineering Center is part of the U.S. Army Research, Development and Engineering Command, which has the mission to provide innovative research, development and engineering to produce capabilities that provide decisive overmatch to the Army against the complexities of the current and future operating environments in support of the Joint warfighter and the nation. RDECOM is a major subordinate command of the U.S. Army Materiel Command.