After more than 10 years of operational use in military and commercial settings, active electronically scanned array radar should soon be aloft in Air Force surveillance operations.
First deployed in 1991, the Air Force's Joint Surveillance Target Attack Radar System (JSTARS) program has come due for a $6 billion recapitalization, which will likely include upgrades to its radar and sensor capabilities. One of those potential improvements could be a step up to AESA technology.
An E-8C Joint Surveillance Target Attack Radar System returns from a mission at Al Udeid Air Base, Qatar, May 1, 2014, after reaching a milestone of 100,000 flying hours to include more than 88,000 hours in the U.S. Central Command area of responsibility since 2001.
Photo Credit: Senior Airman Jared Trimarchi/U.S. Air Force
AESA could make it possible to perform wide-area scans, achieve higher resolution on targets of interest, and achieve multitarget track and attack, all while remaining highly stealthy by dispersing signal emissions across a band of frequencies.
"It's just a much better way of implementing any radar," said Sean Farrell, Air Force JSTARS recap radar integrated product team engineer.
JSTARS recap has drawn the attention of a number of contractors. Boeing has shown an interest, Northrop Grumman says it will team with General Dynamics and Gulfstream, and Lockheed Martin plans to partner with Bombardier and Raytheon. Among these, a number of AESA solutions are percolating up among potential competitors.
At Northrop Grumman, planners note AESA radar will offer greater flexibility by allowing synthetic aperture radar and ground moving target indicator information to be collected simultaneously. The present system can't do both at the same time, said Paul Kalafos, vice president of Northrop Grumman's surveillance systems unit.
"An AESA (radar) also has much faster switching speeds to rapidly move the beam. This allows rapid revisit rates to key areas while still performing other modes encompassing the wide surveillance area," Kalafos said.
Raytheon, meanwhile, is pushing forward with its Skynet radar solution. Despite its JSTARS relationship with Lockheed Martin, Raytheon says it's willing to offer Skynet to all interested parties in the competition.
Skynet already conforms to Navy requirements. As part of JSTARS, it would "also allow the Air Force to leverage a tier one acquisition radar development program that brings current and relevant sensor and processing technologies to bear," said Jerry Powlen, vice president of intelligence, surveillance and reconnaissance systems for Raytheon Space and Airborne Systems.
Skynet draws from a number of current radar technologies including advanced airborne sensor, the littoral surveillance radar system and multiplatform radar technology insertion program to deliver its capabilities, Powlen said. By combining these diverse elements, the system should enable multifunction, moving-target detection, tracking and high-resolution mapping at standoff ranges. Raytheon says the system will detect small, slow-moving targets over extremely large search areas and offer faster revisit rates over multiple search areas simultaneously.
At the heart of these improvements is the AESA configuration, which, unlike previous generations of radar, "provides battlespace awareness, while advanced processors allow for near-simultaneous mapping and tracking," Powlen said. Synthetic aperture radar and inverse synthetic aperture radar imagery allow for target identification and classification.
"Radar modes and overall capability have made great strides since JSTARS was fielded," Kalafos said. Today's tools can better detect very slow-moving targets, deliver automatic target recognition, and counter advanced electronic threats.
Many of these advanced functions are the result of improved computing power. Outside observers say the exponential growth in processor capabilities over recent years is helping to drive these improvements.
"The capability and resolution of the radars are based upon the processing power available, and as time goes by you are getting steadily increased processing power and increased capabilities," said David Deptula, dean of the Mitchell Institute for Aerospace Studies. He is also president of The Deptula Group, and retired Air Force Lt Gen/former deputy chief of staff for ISR, Headquarters, U.S. Air Force.
As processors continue their inevitable advances, "there are always improvements," he said. "We will be able to do more things we weren't able to do when the original JSTARS was built."
Perhaps the most appealing element of emerging AESA solutions will be the tried-and-true nature of these systems.
The Air Force is not looking for cutting-edge upgrades in the JSTARS recap, said Lt Col John Kurian, JSTARS recap mission systems program materiel leader. "This is really to provide existing capabilities on a smaller platform, as quickly as possible."
AESA fits that requirement. It is smaller than its predecessors (how much smaller depends on configuration); it can be deployed tomorrow; and it has already been through the wringer.
Long experience with AESA should help the Air Force bring its JSTARS crews up to speed quickly. "The operators will certainly take lessons learned from other platforms and other missions," Kurian said. "There are specific issues in terms of tracking targets, specific uses in terms of automation. The existing understanding of those will help the operator, especially with fewer crew on board."
In a further effort to speed development and deployment, the Air Force has committed itself to pursuing JSTARS recap using open-systems architecture, meaning that essential systems can be mixed and matched regardless of vendor.
"A lot of our work is focused on trying to make sure we can achieve our goal of being able to integrate new technology in the most efficient manner," Kurian said.
