The presence of sea clutter in marine radar signals is sometimes not desired. So, efficient radar signal processing techniques are needed to reduce it. In this way, nonlinear signal processing techniques based on neural networks (NNs) are used in the proposed clutter reduction system. The developed experiments show promising results characterized by different subjective (visual analysis of the ...

This paper addresses the effects of sea clutter on the clutter-based atmospheric refractivity estimation techniques. It provides a mean square error (MSE) metric for refractivity estimators based on the available clutter-to-noise (CNR) ratio, the type of the sea clutter statistics (Rayleigh, K-distributed and log-normal) and the parameters forming these probability density functions (pdf) such ...

Existing evidence for and against sea clutter being chaotic and nonlinearly predictable is briefly discussed. Despite the uncertainty surrounding the chaotic nature of sea clutter, and its nonlinear predictability, the purpose of this paper is to examine what the best design criterion is for a nonlinear predictor which is to be used to detect targets against clutter which is known to be chaotic...

We investigated the relationship between visual clutter and visual search in real-world scenes. Specifically, we investigated whether visual clutter, indexed by feature congestion, sub-band entropy, and edge density, correlates with search performance as assessed both by traditional behavioral measures (response time and error rate) and by eye movements. Our results demonstrate that clutter is ...

Digital Signal Processing techniques for ground surveillance RADAR has been thoroughly investigated and optimized for an improved detection of target. Using the established techniques like Pulse compression, Fast Fourier Transform and Windowing, the present work optimizes the selection of pulse coding techniques, window type and different filters.The work proposes techniques to mitigate inheren...

A technique is presented to cluster geospatial features on an electronic display and determine a meaningful measure of display clutter. An algorithm previously developed by the Naval Research Laboratory (NRL) to cluster objects in sidescan imagery has been modified to cluster any displayed features in three dimensions: geospatial location (x, y) and color (z). This paper presents preliminary re...

Target objects required for goal-directed behavior are typically embedded within multiple irrelevant objects that may interfere with their encoding. Most neuroimaging studies of high-level visual cortex have examined the representation of isolated objects, and therefore, little is known about how surrounding objects influence the neural representation of target objects. To investigate the effec...

In over-the-horizon radar (OTHR) systems, the signal-to-clutter ratio (SCR) used for moving target detection is very low. For slowly moving targets such as ships, the SCR is typically from 250 dB to 260 dB and their Doppler frequencies are close to that of the clutter. For manoeuvring targets, such as aircraft and missiles, the Doppler frequencies are time-varying when a long integration time i...