Correlation tracking plays an important role in the automation of weapon systems. Area correlation is an effective technique for tracking targets that have neither prominent features nor high contrast with the background and the 'target' can even be an area or a scene of interest. Even though this technique is robust under varying conditions of target background and light conditions, it has some problems like target drift and false registration. When the tracker or target is moving, the registration point drifts due to the discrete pixel size and aspect angle change. In this research work, an attempt has been made to improve the performance of a correlation tracker for tracking ground targets with very poor contrast. In the present work only the CCD visible images with very poor target to background contrast are considered. Applying novel linear and nonlinear filters, the problems present in the correlation tracker are overcome. Confidence and redundancy measures have been proposed to improve the performance by detecting misregistration. The proposed algorithm is tested on different sequences of images and its performance is satisfactory.

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The image seen by the airborne seeker and the image (of the same scene) seen by the operator through the high resolution sensor (thennal sight) are different in spatial resolution. In. orDer to establish the correlation between these two images, the thennal sight image needs to be resampled and made similar to the .seeker image by applying a preprocessing technique. The preprocessing is carried out by a handing over system (HOS) that re samples the thennal sight image making it compatible with seeker image and hands over the resampled image to the seeker . This paper discusses the implementation of the suitable handing over algorithm. (Boland, J.S. et al. Automatic target hand using correlation techniques. Technical report, Auburn University, Alabama, 31 January , 1977, pp. 57-63). Emphasis is laid on developing suitable hardware and software and tests to match the two images obtained by two different sensors of th,; same scene. The hardware and software-have been evaluated with different sets of images. The H/W is designed around iAPX 86 family of processor and software is developed in PUM. Hardware also includes the recording facility on a standard VCR, to record the performance of handing over electronics (HOE) during testing/flight trials. Evaluation of the system by realistically simulating the field scenario in the laboratory has shown that the HOS is functioning satisfactorily. recognition is not possible through the seeker. Thus there is a requirement of a high resolution sensor such as thermal sight (TS) and handing over system (HOS). Ground-based TS can hav~ bigger optics, narrow field of view, high resolution sensor, etc.

The image seen by the(1ow resolution (LR) sensor and the image (of the same scene) seen by the operator through the high resolution (HR) sensor are different in spatial resolution. To establish the correlation between these two images, the HR image needs to be resampled and made similar to the LR sensor image by applying a'pre-processing technique. The pre-processing will be carried out by handing over system that resampies the HK sensor image making it compatible with LR sensor image and hands over the resampled image to the LR sensor through a serial link. The pre-processing technique reported by ~o l a n d ' has been studied, analysed2 and implemented3 using 86 family of processors. Automatic target handing over system discusses the implementation of pre-processing technique, computational complexity and criticality of the execution time. The execution time reported was 1.5 s, whereas the requirement is of the order of few milliseconds for the typical set of conditions. This paper discusses the implementation of a suitable handing over algorithm1 Emphasis has been to develop hardware and software to reduce the execution time, which has been brought down from 1.5 s to 40 ms for a typical set of conditions. Emplrasis has also been given to reduce the transmission time by applying suitable pyramid processing techniques. The hardware is designed around i486 processor, and the software E v e l o p e d in PL/M86.