Real-Time ISAR Image Synthesis of Ballistic Targets

Abstract

Digital image synthesis(DIS) is a specific we make several hypotheses: (1) the rocket has a counter-ISAR technique which employs a false target single-stage and the propellant is consumed during the synthesized to deceive the imaging radar. To make the burn time in a linear fashion;(2) all the forces act on one synthesized false missile images more actual, the point and the moment is not considered; (3) the distribution of the scattering centers for the according longitudinal axis of the missile is aligned with the velocity false object must be similar to the real-timeISAR images vector; (4) the calculation of trajectory is base on a of a true BM over the whole trajectory. This paper Cartesian coordinate system whose x axis andy axis is the presents a novel process to synthesize the images along earth flat and z axis is the height; and (5) the gravity the trajectory which is used as the false target to be acceleration is a constant ie., 9.8 mIs2. synthesized. The kinematic model of the BM is developed flrstly and the trajectory is calculated based on such a Three main forces affect the BM motion, namely, the model. Then the RCS of the BM as a function of the flight thrust, the drag and the gravity. The irust acceleration time is calculated and the time-dependent ISAR image depends on the missile warhead body massMb, the fuel sequences along with the trajectory are formed. The real-time ISAR images of a ballistic target along its massMf, eburnouttimetBOt,ebuningimpulseIs, trajectory being used in false image synthesis can improve and the gravity acceleration. The thrust acceleration acts the counter-ISAR capability of the DIS. along the longitudinal axis of the BM body and the direction is the same as that of the velocity according to the above third hypothesis. After the fuel bums out, the L. Introduction thrust acceleration disappears. The development of ballistic missile defense (BMD)) syThemdevelopmand more efftivcounte miss feasures tt Under the first hypothesis the absolute value of the tirust system demands more effective countermeasures that aclrto a eepesda aim at the target detection and identification sensors used acceleraton can be expressed as in BMD. Digital image synthesis(DIS) is a specific I M counter-ISAR technique which employs a false target =Fth _ f synthesized with the objective of deceiving the imaging M(t) tBJM (t) radar into believing the false target is a real one [1]. Equipped with DIS jammer, a ballistic missile (BNI) can where M(t) is te instantaneous time-varyi mass of protect itself against being destroyed and improve its the BM, penetrability. To make the synthesized false missile Mf images more actual, the distribution of the scattering M(t) = Mb +Mf -r t (2) centers for the according false object must be similar to tBO tie real-time ISAR images of a true BM over the whole The vector of the thrust acceleration can be expressed as: trajectory. de= dthJ*ilV (3)This paper presents a novel process to synthesize the where i4 is the uitary vector of the velocity. images along the traject...

Anti-jamming of Inverse Synthetic Aperture Radar based on Slope-varying Linear Frequency Modulation Signal

“…Besides, US GBR-X has been used to detect ballistic target in favour of anti-missile system seeking and recognition. ISAR with high-resolution, all-day, all-weather and directly observational characteristics plays an important role in military field, which makes the active jamming to ISAR to be a new research area [3,4,6].…”

“…To ISAR deceptive interference, studied done in the technology of digital Anti-jamming of Inverse Synthetic Aperture Radar based on Slope-varying Linear Frequency Modulation Signal image synthesis (DIS) against chirp ISAR, concluded that the DIS combined with high-instantaneous-wideband digital RF memory (DRFM) can synthesise the jamming signal of false target [3]. Another sudy realised a deceptive jamming against ISAR in anti-missile system and studied the method by which the real-time echo signal of false ballistic targets is produced [4]. With the development of ISAR jamming technology, it is important to develop ISAR anti-jamming and strengthen the ISAR electromagnetic combating ability, but less research about ISAR antijamming is reported.…”