Improving the efficiency of military signal jammer for self-protection electronic warfare systems is an important area of research in air operations. Of all the factors that affect jamming performance, two parameters that improve jamming efficiency without changing radar and jamming system design parameters are RCS and range. It is unwise to change the distance between the radar and the target to increase the jamming effect. Because violating the path for the sake of distance can destroy the operational objective. Tuning the RCS for this situation seems to be a suitable way to increase the interference efficiency. According to related research, a new method to improve the interference effect by appropriately changing the RCS is proposed. Therefore, the heading calculator unit is integrated into the self-protection electronic warfare system. The heading calculator interacts with the radar warning receiver and jammer and points to the appropriate heading direction during jamming. Target differences are limited to as small a variation as possible.
Today's technology presents a capable and flexible Integrated Air Defense System (IADS) to potential adversaries. IADS includes different types of modern fighter jets for air interception, advanced multi-frequency radars for surveillance and target acquisition, and high-precision surface-to-air missiles (SAMs) ranging from short-range to long-range for different levels of air defense. Airborne platforms engage in different air operations in an adversary IADS environment, possibly for intelligence, fire support, offensive, and defensive purposes. These airborne platforms are expected to be equipped with special electronic warfare (EW) capabilities known as self-protection electronic warfare suits. These systems detect, deny, disrupt, degrade and evade lethal threats and provide radio frequency (RF), infrared (IR), and laser spectroscopy. In this study, the scope is focused on the RF missile threat, so in this case, the Radio Frequency Countermeasures (RFCM) distributor and the radio frequency jamming subsystem can be considered. Since the study aims to examine the relationship between jamming and radar cross section (RCS), only jamming systems are considered.
The Self-Protection Jamming System is designed to protect airborne platforms from acquisition and target tracking radars from SAM, Airborne Interceptor (AI) and Anti-Aircraft Gun (AAA) systems. Self-protection jamming systems apply noise jamming to generate enough tracking errors to prevent successful engagement or perform deceptive jamming to deny threatening the system's automatic tracking capabilities. Both the noise and deceptive jamming calculations include the effect of the self-protecting jammer platform RCS. In fact, RCS is an element of the radar range equation, which measures the ability of a target to reflect the radar signal in the direction of the radar receiver. Radar detects or tracks a target, and sometimes it can only be identified because of the presence of an echo signal. Therefore, being able to quantify or otherwise describe the echoes is critical in the design and operation of radars, especially in terms of target characteristics such as size, shape, and orientation. For this purpose, targets belong to a valid area called RCS. It is the projected area of the metal sphere and it will return the same echo signal as the target, if the target is replaced by a sphere.
RCS is part of the radar detection process and also directly affects the calculation of the tracking process. For this reason, RCS reduction has been an important area of research and development for many years. Research on RCS reduction for different airborne platforms and surface ships has continued since the 1940s. Especially in the past four years, there has been significant progress in stealth technology to reduce the RCS of different airborne platforms. These studies help make aircraft difficult to detect by radar and give them enough time to react before being tracked.
These methods use different techniques to reduce the RCS of the flying platform. The scope of this work does not apply to all air platforms, especially fighter jets. In the practice of applying the above techniques, different methods are used to reduce the RCS of the fighter. These are as follows:
The shape of the plane's surface causes radar waves to scatter away from the radar.
Different radar absorbing materials (RAM) are used without affecting the flight dynamics.
Apply predetermined maneuver and avoidance strategies under threat.
In addition, fighter jets are hidden or rejected by radar jamming equipment.
In this study, an approach using both RCS reduction and jamming is proposed for fighter jets. The method includes determining the best maneuvering direction to reduce RCS while applying self-protection jamming to the threat system radar. The purpose is to increase the effectiveness of applying jamming. The best solution is to get the highest interference efficiency with slight maneuvering. Before writing the heading calculator, the RCS of the fighter should be measured and the RCS data of all aspects recorded into the calculation computer. Therefore, the low RCS region of the fighter is known, and this information is used in the calculation. The fighter side can be divided into four (or more) sectors and define low RCS areas for each sector. Heading is adjusted for the nearest low RCS area and the calculated heading change is expected to be within reason. As a result, not only is the interference efficiency improved, but the operational objectives are not affected. In any case, the heading calculator only shows the direction in which the effect of jamming is optimized by the electronic warfare self-protection system, and the decision to maneuver in that direction is left to the pilot.
