Joint STARS Research Articles

Joint STARS—The Start of 50 Years of All Speed Surface Moving Target Detection and Tracking

The Joint Surveillance Target Attack Radar System (Joint STARS) radar program was conceived in the mid-1970s as a means of utilizing advanced airborne radar and smart munitions technologies to counter the potential of a massive armed vehicle invasion of Western Europe. Initiated by several cooperative research and development programs sponsored by the U.S. Defense Advanced Research Program Agency (DARPA) and the U.S. Air Force's Advanced Research Laboratories in Rome, NY, USA, and supplemented by parallel complementary research and devleopment activities within various U.S. Army agencies, the technology was developed and field tested in a series of real-world tactical demonstrations. The demonstrations, conducted at the Air Force's extensive facility in Alamogordo, NM, USA, involved combinations of both stationary and remotely controlled tanks deployed in a variety of configurations and, additionally employed state-of-the-art airborne radar sensors from two different large radar system corporations and two different types of autonomous terminally guided multiple-submunition-based weapons designed to achieve multivehicle kills on each weapon launch. DARPA and Air Force programs that contributed to the success of the tactical demonstrations and the ultimate development and operational deployment of the Joint STARS system included Pave Mover and Assault Breaker. Related Army programs included Airborne Long-range Alerting Radar for MTI (ALARM), Project Periodically Elevated Electronic Kibitzer (PEEK), and Stand Off Target Acquisition System (SOTAS).

About Northrop Grumman

The Northrop Grumman (formerly Ryan Aeronautical) RQ-4 Global Hawk (known as Tier II+ during development) is an Unmanned Aerial Vehicle (UAV) used by the United States Air Force and Navy and the German Air Force as a surveillance aircraft. The Northrop Grumman B-2 Spirit (also known as the Stealth Bomber) is an American strategic bomber, featuring low observable stealth technology designed for penetrating dense anti-aircraft defenses; it is able to deploy both conventional and nuclear weapons. The bomber has a crew of two and can drop up to eighty 500 lb (230 kg)-class JDAM GPS-guided bombs, or sixteen 2,400 lb (1,100 kg) B83 nuclear bombs. The B-2 is the only aircraft that can carry large airto-surface standoff weapons in a stealth configuration. The BQM-74 Chukar is a series of aerial target drones produced by Northrop. The Chukar has gone through three major revisions, including the initial MQM-74A Chukar I, the MQM-74C Chukar II and the BQM-74C Chukar III. They are recoverable, remote controlled, subsonic aerial target, capable of speeds up to Mach 0.86 and altitudes from 30 to 40,000 ft (10 to 12,000 m). Northrop Grumman Corporation (NYSE: NOC) is an American global aerospace and defense technology company formed by the 1994 purchase of Grumman by Northrop. The company was the fourth-largest defense contractor in the world as of 2010 and the largest builder of naval vessels. Northrop Grumman employs over 75,000 people worldwide. Its 2010 annual revenue is reported at US$34 billion. Northrop Grumman ranks #72 on the 2011 Fortune 500 list of America's largest corporations and ranks in the top ten military-friendly employers. It has its headquarters in Falls Church, Virginia. Separate sectors, such as Aerospace Systems, produce aircraft for the US and other nations. The B-2 Spirit strategic bomber, the E-8C Joint STARS surveillance aircraft, the RQ-4 Global Hawk and the T-38 Talon supersonic trainer, are used by the US Air Force. The US Army uses Northrop Grumman's RQ-5 Hunter unmanned air vehicle, which has been in operational use for more than 10 years. The US Navy uses Northrop Grumman-built aerial vehicles such as the BQM-74 Chukar, RQ-4 Global Hawk based BAMS UAS, C-2 Greyhound, E-2 Hawkeye and the EA-6B Prowler. Northrop Grumman provides major components and assemblies for different aircraft such as F/A-18 Hornet, F/A-18E/F Super Hornet and the EA-18G Growler. Many aircraft, such as the F-5, T-38 Talon and E-2 Hawkeye are used by other nations.

Wind-Tunnel Measurements of the E-8C Modeled with and Without Winglets

Wind tunnel measurements conducted on a variety of E-8C configurations were collected and compared to flight test data to provide baseline data should new engines be retrofit to the Joint STARS aircraft. The series of wind tunnel tests, which used rapid prototype models of the aircraft, quantified the extent to which the radome yields a destabilizing yaw moment. The data indicated that the lower angles of attack represented the worst-case scenario for directional stability for the clean-aircraft configuration. A wind tunnel model built with the rudder deflected provided a means to compare wind tunnel results to trim conditions acquired through flight tests. A portion of the wind tunnel study was devoted to exploring the effects of winglets on the aircraft. The winglets, with a geometry closely matching the design described in the joint NASA/USAF study of winglets conducted in the 1970’s and 1980’s, increased the directional stability of the aircraft. For the conditions tested, winglets entirely offset the destabilizing effect of the radome. The effect of the winglets, quantified in terms of Cn-s, are consistent with the conclusions of the NASA/USAF study of a KC-135, which like the E-8C, is based on a Boeing 707 configuration.

Radar: the evolution since World War II

Modern radar design has benefited from the evolution of specialized digital processing, allowing high resolution ground mapping, target identification, and target tracking under many conditions. Air-to-air interception makes use of complex decision processes to select from many modes that depend on the clutter backgrounds and flight profiles. Today's multimode radars provide this information for each task while minimizing distractions. Fire control radars support a wide selection of weapons, including cannons and guided missiles. This is possible because of advanced digital processing. In the interval since WW II, radar design evolved from vacuum tubes to semiconductors and then to massively integrated circuits. Computers specialized for fast Fourier transforms (FFTs) have revolutionized radar data processing. System reliability has improved from a few hours to hundreds of hours. Effective built-in test informs ground maintenance personnel of problems for easy maintenance and low failure rates reduce or eliminate field maintenance benches at forward locations. Airborne surveillance radars, such as AW ACS Joint Stars have changed the nature of warfare. Commanders have virtually full view of enemy and friendly forces. Radars, in combination with other remote sensors, provide precise weapon delivery, reducing collateral damage and making all weapons more effective.

Reverse engineering of software threads: A design recovery technique for large multi-process systems

Many software systems currently being deployed in both military and industrial domains serve their users through a large number of concurrent processes. Such systems are expensive and time consuming to build and thus cannot be lightly discarded when circumstances change. Instead, the systems must be able to evolve to meet new challenges. But a software system cannot evolve without an understanding of its design, and such understanding is easily lost when the developers disperse. A particularly difficult problem may be to understand how the many processes cooperate to produce each functionality that the user needs. This paper presents a novel, but relatively simple method for using traces of inter-process messages to recover functional software design threads from a large, multi-process system. The method is illustrated with a preliminary case study of the Joint STARS battle management software. The method seems to be effective in identifying the “as built” threads, and in providing unexpected insights even to Software Engineers who are relatively familiar with the system. Design thread recovery for Joint STARS is feasible because instrumentation to capture inter-process messages was designed into the original system. Our results suggest that the designers of new systems should give thought to including such instrumentation since the cost is small and the future economic benefits in easier evolution could be very large.

Joint STARS phased array radar antenna

The Joint STARS phased array radar system is capable of performing long range airborne surveillance and was used during the Persian Gulf war on two E8-A aircraft to fly many around-the-clock missions to monitor the Kuwait and Iraq battlefield from a safe distance behind the front lines. This paper is a follow-on to previous publications on the subject of the Joint STARS antenna and deals mainly with mission performance and technical aspects not previously covered. Radar data of troop movements and armament installations are presented, a brief review of the antenna design is given, followed by technical discussions concerning the three-port interferometry, gain and sidelobe design approach, cost control, range test implementation and future improvements.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

SPECIALTY ENGINEERING INNOVATIONS ON THE U.S. ARMY JOINT STARS GSM BLOCK I UPGRADE CONTRACT

AbstractThe Joint Surveillance Target Attack Radar System (Joint STARS) proved highly successful during Operation Desert Storm. Although unique circumstances in Operation Desert Storm permitted onequipment contractor support of the system, the U.S. Army is committed to operation and maintenance by the soldier.The new Joint STARS Block I Ground Station Module (GSM) is produced by Motorola Government Electronics Group, and must satisfy a formidable mix of requirements. The system must substantially exceed the complexity and performance levels of the Interim Ground Station Module (IGSM) sent to the Gulf, yet be operable and maintainable by soldiers rather than contractor engineers and technicians. This paper documents the unique interactions and degree of integration associated with the specialty engineering functions on the Joint STARS Block I GSM program, and illustrates the success that can be achieved.

Gulf legacy: from factory floor to desert war

The role in the Persian Gulf War of maintenance and of contractor support of the high-tech systems used is examined. Two of the most difficult maintenance challenges were the F-15E and the Joint Stars surveillance aircraft. The measures that enabled maintenance crews to achieve a full mission-capable rate of 94% for the F-15E are described. The Joint Stars program, in which two modified Boeing 707 aircraft were outfitted with an advanced radar to detect moving targets over vast stretches of ground and provide high-resolution images of some of them, was a developmental project whose operational use was sustained by constant contractor involvement. With a war effort depending on developmental systems too new to have stocks of spare parts, rushing newly minted parts to the theater was of paramount importance. Deployment of men and material was planned, simulated, and monitored on computers. Transportation and logistics within the theater, however, were often horrendous. The Defense Logistics Agency hopes to improve the process with a laser-card-based system. >