8,672 research outputs found
Mode Selection and Target Classification in Cognitive Radar Networks
Cognitive Radar Networks were proposed by Simon Haykin in 2006 to address
problems with large legacy radar implementations - primarily, single-point
vulnerabilities and lack of adaptability. This work proposes to leverage the
adaptability of cognitive radar networks to trade between active radar
observation, which uses high power and risks interception, and passive signal
parameter estimation, which uses target emissions to gain side information and
lower the power necessary to accurately track multiple targets. The goal of the
network is to learn over many target tracks both the characteristics of the
targets as well as the optimal action choices for each type of target. In order
to select between the available actions, we utilize a multi-armed bandit model,
using current class information as prior information. When the active radar
action is selected, the node estimates the physical behavior of targets through
the radar emissions. When the passive action is selected, the node estimates
the radio behavior of targets through passive sensing. Over many target tracks,
the network collects the observed behavior of targets and forms clusters of
similarly-behaved targets. In this way, the network meta-learns the target
class distributions while learning the optimal mode selections for each target
class.Comment: 6 pages, 5 figure
Joint Route Optimization and Multidimensional Resource Management Scheme for Airborne Radar Network in Target Tracking Application
In this article, we investigate the problem of joint route optimization and multidimensional resource management (JRO-MDRM) for an airborne radar network in target tracking application. The mechanism of the proposed JRO-MDRM scheme is to adopt the optimization technique to collaboratively design the flight route, transmit power, dwell time, waveform bandwidth, and pulselength of each airborne radar node subject to the system kinematic limitations and several resource budgets, with the aim of simultaneously enhancing the target tracking accuracy and low probability of intercept (LPI) performance of the overall system. The predicted Bayesian Cramér–Rao lower bound and the probability of intercept are calculated and employed as the metrics to gauge the target tracking performance and LPI performance, respectively. It is shown that the resulting optimization problem is nonlinear and nonconvex, and the corresponding working parameters are coupled in both objective functions, which is generally intractable. By incorporating the particle swarm optimization and cyclic minimization approaches, an efficient four-step solution algorithm is proposed to deal with the above problem. Extensive numerical results are provided to demonstrate the correctness and advantages of our developed scheme compared with other existing benchmarks
Distributed physical sensors network for the protection of critical infrastractures against physical attacks
The SCOUT project is based on the use of multiple innovative and low impact technologies for the protection of space control ground stations and the satellite links against physical and cyber-attacks, and for intelligent reconfiguration of the ground station network (including the ground node of the satellite link) in the case that one or more nodes fail. The SCOUT sub-system devoted to physical attacks protection, SENSNET, is presented. It is designed as a network of sensor networks that combines DAB and DVB-T based passive radar, noise radar, Ku-band radar, infrared cameras, and RFID technologies. The problem of data link architecture is addressed and the proposed solution described
Feature diversity for optimized human micro-doppler classification using multistatic radar
This paper investigates the selection of different combinations of features at different multistatic radar nodes, depending on scenario parameters, such as aspect angle to the target and signal-to-noise ratio, and radar parameters, such as dwell time, polarisation, and frequency band. Two sets of experimental data collected with the multistatic radar system NetRAD are analysed for two separate problems, namely the classification of unarmed vs potentially armed multiple personnel, and the personnel recognition of individuals based on walking gait. The results show that the overall classification accuracy can be significantly improved by taking into account feature diversity at each radar node depending on the environmental parameters and target behaviour, in comparison with the conventional approach of selecting the same features for all nodes
Multistatic human micro-Doppler classification of armed/unarmed personnel
Classification of different human activities using multistatic micro-Doppler data and features is considered in this paper, focusing on the distinction between unarmed and potentially armed personnel. A database of real radar data with more than 550 recordings from 7 different human subjects has been collected in a series of experiments in the field with a multistatic radar system. Four key features were extracted from the micro-Doppler signature after Short Time Fourier Transform analysis. The resulting feature vectors were then used as individual, pairs, triplets, and all together before inputting to different types of classifiers based on the discriminant analysis method. The performance of different classifiers and different feature combinations is discussed aiming at identifying the most appropriate features for the unarmed vs armed personnel classification, as well as the benefit of combining multistatic data rather than using monostatic data only
Deployable antenna demonstration project
Test program options are described for large lightweight deployable antennas for space communications, radar and radiometry systems
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