Signal Intelligence System Uncovers Enemy Sites

Prophet finds what’s present, supports future tactics.

The U.S. Army has a new tool in its arsenal that allows mobile troops to gather intelligence about the location and activities of adversaries by pinpointing the source of signal transmissions and intercepting communications. The system will replace legacy electronic warfare systems that were developed more than 30 years ago, and it has already been deployed in Afghanistan in support of operation Enduring Freedom.

Part of the military’s intelligence gathering mission is to collect information about enemy intentions and to determine the locations of specific targets. One way to obtain this insight is by finding the electronic signature of their communications. Signals intelligence (SIGINT) contributes to situational awareness by adding detail to the profile of the battlespace. Once the source of the signal is determined, military commanders can map the area’s landscape and may, if they choose, employ electronic warfare or other tactics to interrupt communications.

The Prophet system, created and produced by Titan Systems Corporation, San Diego, provides this capability not only from a fixed command post but also on the move. Mounted on a high mobility multipurpose wheeled vehicle (HMMWV), the system allows troops in the field to intercept radio frequency signals, perform signal direction finding and develop actionable intelligence from the voice and communications data. Adversaries are not aware that they are being monitored. The Army’s Program Executive Office Intelligence, Electronic Warfare and Sensors manages the project.

An onboard precision lightweight global positioning system receiver and tactical navigation system interfaces with Prophet to provide accurate worldwide self-positioning location data to within 10 meters, and a north sensing device indicates the heading of the vehicle, which supports on-the-move operations.

A manportable unit that can be removed from the HMMWV allows soldiers to continue gathering SIGINT even when away from the vehicle. The manpack system also can support forced-entry airborne or air assault operations.

The system’s primary mission is to provide continuous force protection to the maneuver brigade. It will be the echelons-division-and-below tactical commander’s sole organic SIGINT, electronic warfare, measurement and signature intelligence, and ground surveillance capability.

In concert with the division tactical unmanned aerial vehicle (TUAV) SIGINT payload, a capability that is currently under development, a division commander will have a comprehensive, near-real-time picture of the enemy’s electronic emitters and the ability to detect, identify, locate and track selected emitters.

Engineering, manufacturing and development models of Prophet-equipped vehicles were part of the military’s initial entry units in Afghanistan in November 2001. Lt. Col. William W. Stevenson, USA, product manager, Prophet, Fort Monmouth, New Jersey, explains that an Army unit, which cannot be identified for security reasons, was using the system in an exercise before operation Enduring Freedom began. Prophet had already successfully completed the test and evaluation stage, so the unit was granted permission to take two systems on its deployment to the Afghan theater of operations.

“The system provides exactly what we have been touting,” Col. Stevenson says. “It offers force protection notification to that unit. It tells the troops where enemy emitters are located and, as a result, the commander can use that information in advance of moving to an area and determine what the unit is going to do in the area. It directly influences the commanders’ plans.”

Prophet has supported multiple operations in Afghanistan, the colonel states, and its reliability has prompted other units to request the system. In fact, plans are currently in the works to determine how the Army National Guard can obtain the equipment for use in Bosnia.

Prophet equipment is about one-third both the weight and the size of legacy systems and offers other distinct benefits. In addition to the on-the-move operation capability, it features digital triangulation to determine the origin of the signal. Legacy systems obtain bearing data that must then be plotted on a map using a grease pencil. And while it can take up to four hours to set up the antenna mast for older systems, the Prophet’s 20-foot mast can be erected in two minutes. Finally, because it uses the HMMWV’s batteries rather than a separate generator as a power source, thermal and acoustics signatures are reduced.

The Prophet’s equipment package includes the single channel ground and airborne radio system (SINCGARS), which provides secure voice communications. Using two receiver-transmitters and two radio amplifiers, Prophet operators can communicate over two networks simultaneously.

HMMWVs equipped with the Prophet system can carry four people as well as enough mission-essential equipment, personal gear and fuel to complete a 72-hour mission.

The technology is being developed using a spiral approach. Prophet Block I contains the electronic support component, which is the receiver/processor. This core system detects and demodulates intercepted enemy signals of interest and determines their lines-of-bearing data. It comprises three receivers: one designated as the direction-finding receiver and two as monitor receivers.

Prophet operates in the high frequency, very high frequency and ultrahigh frequency spectrums. Types of searches include channel scan, fix-tuned, band sweep and manually tuned. Amplitude modulation, frequency modulation, single side-band and continuous wave signals can be demodulated and collected. It covers 10 times the radio frequencies of older electronic warfare systems.

Among the legacy systems Prophet will replace are Trailblazer, Teammate, Trafficjam and the lightweight man-transportable radio direction finding system.

Although the Prophet system is designed primarily to locate signal origination points, Col. Stevenson relates that information collection is equally important. “We are now operating in direct support of a brigade commander. The information is provided to the commander as soon as it is actionable information. This is a polar shift in the way operations are conducted and in the way the information is shared,” he states.

Prophet allows data to be collected and sent back to safe areas where linguists can work on it while the commander plans what to do about the transmitter in the area of operations. “This is a shift in operations because it brings the intelligence, surveillance and reconnaissance information warfare aspect to the immediate forefront of the commander,” the colonel says. Because this information can be combined with intelligence gathered by other means, capabilities dynamically increase, he adds.

Col. Kevin Peterson, USA, training and doctrine system manager, Prophet, Fort Huachuca, Arizona, points out that the system informs commanders of what is in front of and around them. It gives the commander the option to either destroy or not destroy an enemy communications post or to maneuver out of contact.

The Training and Doctrine Command’s (TRADOC’s) role has been critical to the development of Prophet, Col. Peterson explains. By working with users, TRADOC identified requirements for the system. It also has determined how doctrine must change as a result of the new capability. As the new system is introduced, TRADOC will conduct training and will adjust current courses to reflect the changes the capability brings to operations.

“We are working hand-in-hand with Objective Force personnel to roll this into Objective Force initiative plans because the equipment in 2008 will have Prophet embedded in it, and those forces will need to be very familiar with it,” Col. Peterson explains.

Originally, Prophet’s Block II and Block III rollouts involved two distinct sets of improvements to the initial equipment. However, the Army has since combined the two, now calling the upgrades Block II/III, and companies are competing for the project. The improvements at this phase are scheduled to include an electronic warfare jamming capability and to increase the types of signals Block I equipment detects to include low-probability-of-intercept, modern and frequency-hopping signals.

Current plans call for the Block II/III contract to be awarded in December 2002, with operational test and evaluation of the system scheduled for summer 2004. During the first quarter of fiscal year 2005, a production decision will be made, and the upgrades should be made in late 2005 and 2006, Col. Stevenson says.

Ronald Gorda, senior vice president, Titan Systems Corporation, explains that Titan already has been working on the next generation of equipment. The open architecture design of the system will facilitate the incorporation of future improvements and allow for maximum reuse of the equipment when upgrades are developed, Gorda says.

Currently, 37 vehicles are in full production, and Titan is scheduled to deliver a total of 83 Prophet-equipped HMMWVs to the Army by 2004. The fielding plan calls for each division to get six models. Each armored cavalry regiment is scheduled to receive four systems, while Stryker brigades will each receive three and separate infantry brigades will each receive two. Five Prophet systems will be delivered to TRADOC to meet institutional training requirements.

Improvements to the system will continue in the Block IV and Block V stages. Scheduled upgrades in the Block IV would add a measurement and signature intelligence (MASINT) capability to the Prophet system on a separate vehicle. The MASINT component may feature mobile, unattended platform-based sensors and unattended ground sensors that would be deployed as a distributed and networked sensor array. In addition, when combined with the upgraded Block II/III electronic support platform, the warfighter will have a multispectral sensor system capability. SIGINT and MASINT capabilities may be fused in future combat vehicles. Col. Peterson explains that Block IV capabilities are set to coincide with the Objective Force in 2008.

Col. Peterson predicts that Block V enhancements will be online around 2015 and will incorporate microsensors and robotic platforms. As envisioned, electronic warfare, SIGINT, MASINT and direction finding capabilities would allow commanders to tailor the collection of information to changing mission requirements.

While improved ground-based SIGINT capabilities are being introduced in the field, the Army also is in the process of developing similar intelligence gathering capabilities from the air. The division TUAV signals intelligence program (DTSP) currently is in the component advanced development stage with three companies proposing designs.

The DTSP will allow commanders to electronically map radio frequency emitters on the battlefield and conduct electronic attacks against targeted emitters. It is envisioned to feature two components. The SIGINT and electronic warfare payloads would be installed on the TUAV, while the workstation software would control the mission payload remotely and display and analyze the data.

According to Col. Stevenson, the technologies will be demonstrated at Fort Huachuca during the middle of 2003, and a contract will be awarded in fiscal year 2004 or fiscal year 2005.

To ensure that these SIGINT capabilities can be used in joint and coalition environments, the Army has been working with intelligence agencies, the special operations community and all the services as well as other nations. The equipment is interoperable with other systems to ensure that the data that is collected can be shared, Col. Stevenson says.