Neural Network-Based Multi-Target Detection within Correlated Heavy-Tailed Clutter

This work addresses the problem of range-Doppler multiple target detection in a radar system in the presence of slow-time correlated and heavy-tailed distributed clutter. Conventional target detection algorithms assume Gaussian-distributed clutter, but their performance is significantly degraded in the presence of correlated heavy-tailed distributed clutter. Derivation of optimal detection algorithms with heavy-tailed distributed clutter is analytically intractable. Furthermore, the clutter distribution is frequently unknown. This work proposes a deep learning-based approach for multiple target detection in the range-Doppler domain. The proposed approach is based on a unified NN model to process the time-domain radar signal for a variety of signal-to-clutter-plus-noise ratios (SCNRs) and clutter distributions, simplifying the detector architecture and the neural network training procedure. The performance of the proposed approach is evaluated in various experiments using recorded radar echoes, and via simulations, it is shown that the proposed method outperforms the conventional cell-averaging constant false-alarm rate (CA-CFAR), the ordered-statistic CFAR (OS-CFAR), and the adaptive normalized matched-filter (ANMF) detectors in terms of probability of detection in the majority of tested SCNRs and clutter scenarios.Comment: Accepted to IEEE Transactions on Aerospace and Electronic System

Fundamental aspects of netted radar performance

Netted radar employs several spatially distributed transmitters and receivers for information retrieval. This system topology offers many advantages over traditional monostatic and bistatic systems which use a single transmitter and a single receiver. For example, it provides better utilization of reflected energy, more flexible system arrangement and enhanced information retrieval capability. Therefore, the netted radar system is of emerging interests among radar researchers. This work investigates several fundamental aspects that determine netted radar performance. This includes netted radar sensitivity, the netted radar ambiguity function and the netted radar ground plane effect. Mathematical models are developed to provide a mean to examine different aspects of netted radar performance. Software simulations examine netted radar performance over a range of parameter variations. Simulation results show that netted radar can offer better performance over traditional monnostatic and bistatic radar in many cases. Some elementary field trials have been conducted using a prototype netted radar system developed within the UCL radar group to examine aspects of netted radar performance in practice. The field trials are focused on netted radar range and sensitivity which are fundamental. The field trial results show that the theoretical benefits that netted radar can offer are generally realizable in practice

Middle Atmosphere Program. Handbook for MAP, volume 28

Extended abstracts from the fourth workshop on the technical and scientific aspects of MST (mesosphere stratosphere troposphere) radar are presented. Individual sessions addressed the following topics: meteorological applications of MST and ST radars, networks, and campaigns; dynamics of the equatorial middle atmosphere; interpretation of radar returns from clear air; techniques for studying gravity waves and turbulence; intercomparison and calibration of wind and wave measurements at various frequencies; progress in existing and planned MST and ST radars; hardware design for MST and ST radars and boundary layer/lower troposphere profilers; signal processing; and data management

Middle Atmosphere Program. Handbook for MAP, volume 20

Various topics related to investigations of the middle atmosphere are discussed. Numerical weather prediction, performance characteristics of weather profiling radars, determination of gravity wave and turbulence parameters, case studies of gravity-wave propagation, turbulence and diffusion due to gravity waves, the climatology of gravity waves, mesosphere-stratosphere-troposphere radar, antenna arrays, and data management techniques are among the topics discussed

Bloodlines

Bloodlines is a collection of personal essays that focus on the process of remembering, imagining, and reflecting on the past through the lens of a perpetually shifting present. They consider situations ranging from mental and physical illnesses, from cancer to alcohol addiction, to career changes, to the often dysfunctional and displaced family ties that distance and adulthood have not severed. In Searching, I write the narrative of the ongoing search for my birthmother, and how the search complicates the relationship with my adoptive mother, who always feared she’d lose me. Similarly, Of Flesh and Blood recounts and negotiates how hereditary and environmental factors have shaped my identity. Loss and betrayal are weaved throughout Flight Patterns when I trace the links between relationships among my family and my pets. In Signs and Stars and Seeing Stars, I search for ways of dealing with my cancer diagnosis and alcoholism, weaving through my past as I fight for recovery. By exploring the subjective nature of memory and circumstance through sensory, expositional, structural, and even written documentation, I have attempted to capture what is, for me, the tenuous hold on intertwined moments in time by creating a palimpsest of perspectives

Visual Analysis of Large, Time-Dependent, Multi-Dimensional Smart Sensor Tracking Data

Technological advancements over the past decade have increased our ability to collect data to previously unimaginable volumes [Kei02]. Understanding temporal patterns is key to gaining knowledge and insight. However, our capacity to store data now far exceeds the rate at which we are able to understand it [KKEM10]. This phenomenon has led to a growing need for advanced solutions to make sense and use of an ever-increasing data space. Abstract temporal data provides additional challenges in its, representation, size, and scalability, high dimensionality, and unique structure.One instance of such temporal data is acquired from smart sensor tags attached to freely roaming animals recording multiple parameters at infra-second rates which are becoming commonplace, and are transforming biologists understanding of the way wild animals behave.The excitement at the potential inherent in sophisticated tracking devices has, however, been limited by a lack of available software to advance research in the field. This thesis introduces methodologies to deal with the problem of the analysis of the large, multi-dimensional, time-dependent data acquired. Interpretation of such data is complex and currently limits the ability of biologists to realise the value of their recorded information.We present several contributions to the field of time-series visualisation, that is, the visualisation of ordered collections of real value data attributes at successive points in time sampled at uniform time intervals. Traditionally, time-series graphs have been used for temporal data. However, screen resolution is small in comparison to the large information space commonplace today. In such cases, we can only render a proportion of the data.It is widely accepted that the effective interpretation of large temporal data sets requires advanced methods and interaction techniques. In this thesis, we address these issues to enhance the exploration, analysis, and presentation of time-series data for movement ecologists in their smart sensor data analysis

Butterflies of the southern Rocky Mountains area, and their natural history and behavior

This book reports the biology of the butterflies of the southern Rocky Mountains area, including all the species in Colorado, although surrounding areas are also discussed, especially the rest of the Southern Rocky Mts. in Wyoming and New Mexico and into Utah. This book presents what is known of the biology of the butterflies of Colorado and vicinity, including hostplants, eggs/larvae/pupae appearance and habits, behavior including flight habits and migration and mate-locating and mating and basking and roosting, and the flowers and other foods of adult butterflies, and natural history aspects of their biochemistry, plus mimicry, flight periods and number of generations, etc. It also includes taxonomic matters to assist identification of all the species and subspecies and forms. Much research on the biology of Colorado area butterflies has been done recently, but it has been published in many scattered publications and scientific journals and is not readily available, and some good research is unpublished; this book attempts to make it available, and provides the sources for good published research.Text only. To view Papilio (New Series) #28, 29, 30, 31 for photos, please see Associated Publications below