In the “gee-whiz” awesomeness of proliferating GNSS apps, it’s sometimes hard to remember that Global Positioning System originated as a military system designed to meet strategic and tactical needs on the battlefield.

And, with the U.S. Air Force continuing its 40-year mission as the executive agent for sustaining GPS, that undiminished military role plays no small part in ensuring the availability and reliability of the U.S. contribution to the GNSS system of systems.

The long road traveled by the Department of Defense (DoD) in bringing GPS to its prominent, even dominating, presence in the world of positioning, navigation, and timing (PNT) has encountered a growing number of challenges in recent years: budgetary constraints, pressures to modernize in a technologically evolving world, the recognition of GNSS vulnerabilities and physical constraints, and the need to accommodate civil, commercial, and scientific user communities along with the military services.

In the early years of the GPS program, for instance, some people thought that the new satellite-based technology would replace many legacy navigation systems, including those operated by the DoD. More recently, with growing awareness of the limitations of GPS access in some operational environments, as well as vulnerability to interference and jamming, defense officials seem to have re-set their expectations for GPS as they look for robust and ubiquitous PNT capabilities.

Another challenge: Even as the new military M-code signal becomes implemented on a growing number of GPS satellites, the GPS Directorate continues to search for the best way forward in getting M-code–capable receivers onto platforms and, especially, into the hands of military personnel in the field.

To address these and other questions regarding the role of GNSS in military affairs and the role of the military in GNSS affairs), we turned to Doug Taggart, president of Overlook Systems Technologies, Inc. Based in Vienna, Virginia, Overlook has a deep grounding in GPS, supporting over the years the Office of the Secretary of Defense (C3I, NII, AT&L and CIO), the Joint Staff, Secretary of the Air Force Acquisition Office, Departments of the Army and Navy, Air Force Space Command Headquarters, 50th Space Wing, and Space and Missile Systems Center (SMC) Global Positioning Systems (GPS) Directorate.

A former radionavigation program manager for the U.S. Coast Guard, Taggart earned a BSEE degree from the U.S. Coast Guard Academy and an M.S. degree in electrical and electronic engineering from Purdue University.