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Quantum key distribution (QKD) provides the opportunity to deliver unconditional communication security. The most robust version of QKD relies on quantum entanglement. Very recently, ubiquitous deployment of such entanglement-based QKD over large distances has moved closer to reality, as verified by quantum entanglement distribution from a low Earth orbit satellite. We will demonstrate that this robust...
In this paper, we propose a robust Student's t filtering algorithm designed for Cooperative Navigation (CN) for Autonomous Underwater Vehicles (AUVs). In a CN system, an acoustic communication technique is usually used to exchange information and measure range between AUVs, and many cheap but low-accuracy Micro-Electro-Mechanical Systems (MEMS)-based Inertial Measurement Units (IMUs) are used as Dead-Reckoning...
In-shore and off-shore wind farms are nowadays representing strategic assets for the generation of clean energy. However their presence interferes with existing surveillance systems, such as primary radar systems. In order to achieve painless coexistence of radar and wind farms systems, solutions can be explored from both the renewable energy and radar communities. In particular, this paper deals...
This paper addresses the identification of sourcesensor transfer functions from the measured space-time covariance matrix in the absence of any further side information about the source or the propagation environment. Using polynomial matrix decomposition techniques, the responses can be narrowed down to an indeterminacy of a common polynomial factor. If at least two different measurements for a source...
A distributed spectral clustering algorithm to group sensors based on their location in a wireless sensor network (WSN) is proposed. For machine learning and data mining applications in WSN's, gathering data at a fusion center is vulnerable to attacks and creates data congestion. To avoid this, we propose a robust distributed clustering method without a fusion center. The algorithm combines distributed...
In traditional direction-of-arrival (DoA) estimation, the number of sources to be detected is widely assumed to be smaller than the number of physical sensors. In practice, however, the number of sources encountered may be greater than that of the sensors. To address this problem, nested array structure can be considered, however, the effects of mutual coupling between sensors may become significant...
Employing the stepped-frequency waveforms is an efficient way to improve the range resolution of synthetic aperture radar (SAR) retaining the benefits of low instantaneous bandwidth. A conventional stepped-frequency waveform used in high-resolution SAR is stepped-frequency chirp signal (SFCS). Range sidelobe suppression of SFCS can be improved if minor frequency overlap between pulses is introduced...
This paper presents the design and implementation of an inexpensive and generic Spectrum Alerting System (SAS), based on Software Defined Radio (SDR), by using the RTL-SDR USB device and a low- power microprocessor Raspberry Pi. The main aim of the SAS is within a defence surveillance system for discovering rogue or unidentified signals in an attentive spectrum, sending alerts to the signals intelligence...
Cyber-security threats are a growing concern in networked environments. The development of Intrusion Detection Systems (IDSs) is fundamental in order to provide extra level of security. We have developed an unsupervised anomaly-based IDS that uses statistical techniques to conduct the detection process. Despite providing many advantages, anomaly-based IDSs tend to generate a high number of false alarms...
Nonlinearity in Raman spectral mixtures caused by wavenumber shifts, has been investigated in this paper. The spectral shifts are mainly caused by the existence of multiple chemicals in the mixtures, with complex molecular interactions, which can change the spectral features of each constituent. While such non-linear behaviour may be negligible in some mixtures, it may lead to incorrect identification...
Image analysis methods that are based on exact blur values are faced with the computational complexities due to blur measurement error. This atmosphere encourages scholars to look for handcrafted and learned features for finding depth from a single image. This paper introduces a novel exact realization for blur measures on digital images and implements it on a new measure of defocus Gaussian blur...
Classification of pulse repetition interval (PRI) modulation type is an important task of electronic warfare systems. Correct classification of the PRI modulation of an emitter can lead to significant knowledge about the observed emitter and can facilitate an electronic warfare system with applying its functions. Several methods have been proposed in the literature for identifying standard PRI modulation...
We investigate the detection and classification of human motions using ambient 802.11 wifi signals. Extensive experiments are conducted and show that different human motions introduce unique patterns in the received signal waveforms. As a starting point of the research, the Received Signal Strength (RSS) is explored as a reliable measurement due to its easy implementation and robustness against frequency...
In this paper, an enhanced Gaussian mixture probability hypothesis density filter (GM-PHD) using convolutional neural network (CNN) based weight penalization is proposed to track multiple targets in video. Existing GM-PHD filter based tracking methods are not always able to accurately track the targets when they are in close proximity, especially with noisy detection responses or in a crowded environments...
This paper presents a new method for DOA estimation using multiple distributed antenna arrays. Unlike conventional methods that process covariance matrix at each array, the proposed method is based on cross-correlation matrix between two arrays. This method does not require the beamforming step in order to associate different DOAs from different antenna arrays. More importantly, this method, by exploiting...
In a previous work, model based automatic target recognition (ATR) from synthetic aperture radar (SAR) images is implemented through matching between the three-dimensional (3D) hot scattering point images (HSPI) and the 3D back projection scattering images (BPSI), where HSPI is generated from 3D model, while BPSI is formed from SAR images projecting onto a 3D target geometrical model. A technique...
Passive Bistatic Radar (PBR) systems use non- cooperative illuminations of opportunity to detect, localise and track targets. The aim of this paper is to investigate the potential of PBR target detection in the presence of non-random signals emitted by non-cooperative transmitters of opportunity, such as radar systems, and without the use of a reference channel. An experiment to detect a moving target...
In blind source separation (BSS), the number of sources present in the measured speech mixtures is unknown. The focus of this work is therefore to automatically estimate the number of sources from binaural speech mixtures. Collapsed Gibbs sampling (CGS), a Markov chain Monte Carlo (MCMC) technique, is used to obtain samples from the joint distribution of the speech mixtures. Then the Chinese Restaurant...
A number of algorithms capable of iteratively calculating a polynomial matrix eigenvalue decomposition (PEVD) have been introduced. The PEVD is a generalisation of the ordinary EVD and will diagonalise a parahermitian matrix via paraunitary operations. Inspired by the existence of low complexity divide-and-conquer solutions to eigenproblems, this paper addresses a divide-and-conquer approach to the...
The paper considers signal-to-interference ratio (SIR) based macro-diversity reception with macro level (MaL) selection combining (SC) diversity and three dual branch SC diversity receivers at micro level (MiL) in correlated Gamma shadowed Rayleigh multipath fading environment. Rapidly converging, infinite series expression for outage probability (OP) is obtained, graphically presented and analyzed...
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