In this paper, we focus on cooperative spectrum sensing (CSS) for double threshold improved energy detector. In this method, the improved energy detector compares positive power operation p of the amplitude of received signals at each secondary user (SU) with two thresholds to make binary decision about presence or absence of primary user (PU). The energies lying between upper and lower thresho...

Our previous work on stochastic resonance (SR) in threshold based systems proved that the SR effect is dependent on the nature of the input signal distribution; more specifically, for certain types of signal distribution SR is not observed [Das A, Stocks NG, Nikitin A, Hines EL. Quantifying stochastic resonance in a single threshold detector for random aperiodic signals. Fluctuation Noise Lett ...

The lobula giant motion detector (LGMD) is a wide-field bilateral visual interneuron in North American locusts that acts as an angular threshold detector during the approach of a solid square along a trajectory perpendicular to the long axis of the animal (Gabbiani et al., 1999a). We investigated the dependence of this angular threshold computation on several stimulus parameters that alter the ...

Cognitive Radio threshold optimization has been an on-going research concern. With mature energy detector algorithms, the CR implemented in this work uses an energy detector as the primary sensing module for the primary user signal. In order to achieve this detection in an efficient way, various techniques have been proposed in literature for optimization and different levels of optimization ha...

We present the results of a search for Extreme Ultraviolet emission in A4059, a cluster with an Xray emitting cluster gas. Our analysis of Extreme Ultraviolet Explorer (EUVE) Deep Survey observations of this cluster shows that it is associated with diffuse EUV emission. Outside the central 2 arcmin radius the entire EUV emission detected is explained by the low energy tail of the X-ray emitting...

The Milagro Gamma Ray Observatory, located at an altitude of 8,600 feet in the Jemez Mountains of New Mexico, is the world’s first large-area water Cherenkov detector capable of continuously monitoring the entire sky for sources of TeV gamma rays. It is uniquely capable of searching for transient sources of VHE gamma rays. The core of the detector is a 60m x 80m x 8m pond instrumented with 723 ...

We developed a framework to evaluate the performance of a detection system for contaminated surfaces. We employ the radiative transfer model for contaminated surfaces (Ben-David and Davidson, ECBC-TR-1084, 2013) and transform the physical model into a stochastic probability model with which detection probability and false alarms can be estimated for scenarios of interest. Our algorithm employs ...

Detecting and tracking small targets in the aerospace is both a significant and difficult issue for the satellite tracking system. It is fundamentally challenging due to the existence of strong noise in captured images, the few characteristics of spot-like target, the simultaneous multiple targets, the real-time requirements, and so on. To address these challenges, we respectively design the de...