Moving target indication

About: Moving target indication is a research topic. Over the lifetime, 2653 publications have been published within this topic receiving 32435 citations.

Track-before-detect for fluctuating targets using phase information

Abstract: The fluctuating target tracking problem through the use of dynamic programming based track-before-detect (DP-TBD) is considered in this paper. The target is modelled by the well-known Swerling family of target amplitude fluctuation models in order to capture the effect of radar cross-section changes that a target would present to radar over time. For each of the target fluctuation models, the complex likelihood ratio (CLLR), which utilizes the target amplitude fluctuation information together with the phase information, is derived and used in the integration process of DP-TBD. Simulation results show a significant gain in detection and tracking performance through accurately modeling the target amplitude fluctuations.

GMTI motion compensation

Abstract: Movement of a GMTI radar during a coherent processing interval over which a set of radar pulses are processed may cause defocusing of a range-Doppler map in the video signal. This problem may be compensated by varying waveform or sampling parameters of each pulse to compensate for distortions caused by variations in viewing angles from the radar to the target.

CART III: Improved camouflage assessment using moving target indication

Abstract: In order to facilitate systematic, computer aided improvements of camouflage and concealment assessment methods, the software system CART (Camouflage Assessment in Real-Time) was built up for the camouflage assessment of objects in image sequences (see contributions to SPIE 2007 and SPIE 2008 [1], [2]). It works with visual-optical, infrared and SAR image sequences. The system comprises a semi-automatic annotation functionality for marking target objects (ground truth generation) including a propagation of those markings over the image sequence for static as well as moving scene objects, where the recording camera may be static or moving. The marked image regions are evaluated by applying user-defined feature extractors, which can easily be defined and integrated into the system via a generic software interface. This article presents further systematic enhancements made in the recent year and addresses particularly the task of the detection of moving vehicles by latest image exploitation methods for objective camouflage assessment in these cases. As a main topic, the loop was closed between the two natural opposites of reconnaissance and camouflage, which was realized by incorporating ATD (Automatic Target Detection) algorithms into the computer aided camouflage assessment. Since object (and sensor) movement is an important feature for many applications, different image-based MTI (Moving Target Indication) algorithms were included in the CART system, which rely on changes in the image plane from an image to the successive one (after camera movements are automatically compensated). Additionally, the MTI outputs over time are combined in a certain way which we call "snail track" algorithm. The results show that their output provides a valuable measurement for the conspicuity of moving objects and therefore is an ideal component in the camouflage assessment. It is shown that image-based MTI improvements lead to improvements in the camouflage assessment process.

Sequential automatic gain control circuit

Abstract: The sequential automatic gain control circuit is an improved AGC circuit that can be used in search and track radars which receive a series of pulse returns from each target. The sequential AGC is well suited for monopulse radars and moving target indication (MTI) processing where gain stability and gain match between channels are required. The maximum input signal levels are sensed by a pair of AGC circuits which alternately provide output levels for a predetermined time. The output signal levels are proportional to the maximum input signal received during the previous pulse return period.