JAMFEST

Testing Your Way Out of a GPS Jam

With attempts to jam GPS signals posing an ever-greater threat to military and civilian users, the real-world scenarios put together by the U.S. Defense Department’s lead GPS test organization help warfighters, defense contractors, and civil agencies evaluate the resistance or vulnerability of their equipment to unwanted interference.

Paul Benshoof, Angelo Trunzo, and 2d Lt Nick Uptain, 746th Test Squadron

Last November, the 746th Test Squadron (746 TS) planned and executed the latest installment in an innovative GPS jamming exercise at White Sands Missile Range (WSMR), New Mexico. Known as JAMFEST, this program is aimed at providing low cost, realistic, GPS jamming scenarios for testing GPS-based navigation systems, as well as training personnel in unique GPS denied environments.

Located at Holloman Air Force Base, New Mexico (NM), the 746th Test Squadron, also known as the Central Inertial and GPS Test Facility (CIGTF), is the U.S. Department of Defense (DoD) designated lead test organization chartered to test and evaluate GPS user equipment and integrated GPS-based guidance and navigation systems.

Through partnership with the GPS Wing and the Joint Navigation Warfare Center (JNWC), the 746 TS is able to provide this diverse testing and training opportunity at a significantly reduced cost to JAMFEST participants.

During JAMFEST ’07 — the fifth JAMFEST event since the concept was introduced in 2004 — the 746 TS hosted 17 simultaneous, yet very dissimilar customers, including multi-service DoD agencies, several defense contractors, and other government and civil
organizations.

. . . The overall goal of JAMFEST ’07 was to provide and characterize the GPS jamming environment in multiple configurations to enable the participants to test, train, or gain experience in a GPS-jammed scenario.

. . . One of the primary test resources used to create the jamming environment is the Portable Field Jamming System (PFJS), a modified Ford 350 van with a full suite of GPS electronic warfare (EW) equipment. PFJS elements include TMC Advanced Threat Emulators (TATEs) and TAVIA-32 Emulators (TAVIAs), as well as a variety of high power adjustable amplifiers.

. . . JAMFEST testing began on November 5, 2007, at 1500 MST and spanned the following five days. During the test week, 746 TS engineers conducted GPS jamming operations for 7-8 hours on each test day, and characterized the jamming field with ground and airborne monitoring equipment.

The next JAMFEST is scheduled for mid January, 2009.

For the complete story, including figures, graphs, and images, please download the PDF of the article, above.

Manufacturers

The CIGTF Reference System uses an H-764GU Embedded GPS/INS Navigation System, from Honeywell Sensor & Guidance, Clearwater, Florida, USA; Ashtech Z/G-12 receivers from Magellan Corporation, Santa Clara, California, USA; Force 5 GPS receivers from Trimble Navigation, Sunnyvale, California, USA; and an LR Rover from Locata Corporation Pty Ltd., Acton ACT, Australia.

The fixed radiation pattern antennas are Dorne and Margolin C146-2-1 from ITT/Edo Corporation, Bohemia, New York, USA. The controlled radiation pattern antennas are GAS-1 antennas from Raytheon Systems Limited, Harlow, Essex, United Kingdom. The Portable Field Jamming Systems and Portable Box Jammers use TMC Advanced Threat Emulators and TAVIA-32 Emulators from TMC Design Corporation, Las Cruces, New Mexico, USA.

Author Profiles

Paul Benshoof is chief of strategic operations at the 746th Test Squadron, Holloman AFB, New Mexico. He is a co-creator of the JAMFEST concept, has orchestrated several JAMFEST events, and actively continues to support the planning and execution of future JAMFEST events. He has spent the last 18 years in GPS with duties that include directing the GPS Test Center of Expertise, leading the development and procurement of secure handheld GPS receivers for the Army, developing assets to support navigation warfare advanced technology demonstrations, and supervising international test programs for NATO and allied forces.

Angelo Trunzo is currently the director of the GPS Test Center of Expertise, a multi-service consortium of GPS test organizations. Operating out of the 746th Test Squadron at Holloman AFB, New Mexico, he actively participates in JAMFEST planning and several GPS integrated test teams (ITTs), including the GPS Enterprise ITT. Past assignments have featured design and analysis, environmental testing, and test management that have included the Responsible Test Organization function for the USAF Joint Precision Approach Landing System (JPALS).

U.S. Air Force 2Lt Nick Uptain is the lead JAMFEST test manager at the 746th Test Squadron, Holloman AFB, New Mexico. His experience as a GPS vulnerabilities test manager includes testing of the Advanced Medium Range Air-to-Air Missile (AMRAAM), Joint Directed Attack Monition (JDAM) at the Weapon System Evaluation Program (WSEP), and operational training against micro-GPS jammers for carrier wing exercises.