Presents the table of contents for this issue of the publication.

Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.

Presents the table of contents for this issue of the publication.

Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.

Presents the table of contents for this issue of this publication.

Provides a listing of current staff, committee members and society officers.

Kalman filter-based retrodiction plays an indispensable role in modern multitarget tracking and retrodiction (MTTR) algorithms. To this end, the Rauch–Tung–Striebel (RTS) smoother is a widely used Kalman filter-based target state smoother. With a large number of targets, MTTR algorithms, particularly with large window sizes, become very computationally intensive. If not addressed, these algorithms

This paper presents an innovative control architecture for tilt-rotor quadcopters with H-configuration transporting unknown, sling payloads. This control architecture leverages on a thorough analysis of the aircraft's equation of motion, which reveals gyroscopic effects that were not fully characterized and were disregarded while synthesizing control algorithms in prior publications. Furthermore, the

Reusable liquid-propellant rocket engines (LPREs) imply more demanding robustness requirements than expendable ones due to their extended capabilities. Therefore, the goal of this work was to develop a control loop adapted to all the operating phases of LPRE, including transients, and robust to internal parametric variations. Firstly, thermo-fluid-dynamic simulators representative of the gas-generator-cycle

Recent work have shown how the optimal state-feedback, obtained as the solution to the Hamilton-Jacobi-Bellman equations, can be approximated for several nonlinear, deterministic systems by deep neural networks. When imitation (supervised) learning is used to train the neural network on optimal state-action pairs, for instance as derived by applying Pontryagin's theory of optimal processes, the resulting

Global Navigation Satellite Systems (GNSS) provide ubiquitous, continuous and reliable positioning, navigation and timing information around the world. However, GNSS space segment design decisions have been based on the precursor Global Positioning System (GPS), which was designed in the 70s. This paper revisits those early design decisions in view of major technological advancements and new GNSS environmental

Nowadays, mutual interference among automotive radars has become a problem of wide concern. In this paper, a decentralized spectrum allocation approach is presented to avoid mutual interference among automotive radars. Although decentralized spectrum allocation has been extensively studied in cognitive radio sensor networks, two challenges are observed for automotive sensors using radar. First, the

This paper provides a comparative performance analysis of different acquisition and tracking methods of GPS L1 C/A and GPS L5 signals testing their robustness to the presence of scintillations in the propagation environment. The paper compares the different acquisition methods in terms of probabilities of detection/false alarm, peak-to-noise floor ratios for the acquired signal and execution time,

Land vehicle navigation based on inertial navigation system (INS) and odometers is a classical autonomous navigation application and has been extensively studied over the past several decades. In this work, we seriously analyze the error characteristics of the odometer (OD) pulses and investigate three types of odometer measurement models in the INS/OD integrated system. Specifically, in the pulse

Model-based approaches for target tracking and smoothing estimate the infinite number of possible target trajectories using a finite set of models. This paper proposes a data-driven approach that represents the possible target trajectories using a distribution over an infinite number of functions. Recursive Gaussian process and derivative based Gaussian process approaches for target tracking and smoothing

In this study, an intelligent predictor-corrector entry guidance approach for lifting hypersonic vehicles is proposed to achieve real-time and safe control of entry flights by leveraging the deep neural network (DNN) and constraint management techniques. First, the entry trajectory planning problem is formulated as a univariate root-finding problem based on a compound bank angle corridor, and two constraint

A nonlinear controllability analysis for fixed-wing aircraft has been performed in an earlier effort by the authors, which revealed a novel roll mechanism due to a nonlinear interaction between elevator and aileron control inputs. In this effort, we perform a detailed investigation of this novel roll mechanism, called LIBRA (Lie Bracket Roll Augmentation). First, we show the nonlinear flight physics

The utilization of extremely high frequency (EHF) bands can achieve very high throughput in satellite networks (SatNets). Nevertheless, the severe rain attenuation at EHF bands imposes strict limitations on the system availability. Smart gateway diversity (SGD) is considered indispensable in order to guarantee the required availability with reasonable cost. In this context, we examine a load-sharing

Formation reconfiguration of multiple unmanned aerial vehicles (UAVs) is a challenging problem. Mathematically, this problem is an optimal control problem subject to continuous state inequality constraints and terminal state equality constraints. The first challenge is that there are an infinite number of constraints to be satisfied for the continuous state inequality constraints, which makes the problem

Maximizing the coherent processing interval (CPI) is crucial when performing passive radar detection on weak signal reflections. In practice however, the CPI is limited by the target movement. In this work, the extent of the range and Doppler migration effects occurring when using a long CPI to integrate the returns from an L-band digital aeronautical communication system (LDACS) based passive radar

Linear least squares (LS) frequency estimators are popular because they are closed-form and easy to implement. However, they are applicable to compressive frequency estimation only after reconstruction. This is because compressive sensing (CS) breaks up the temporal order of the original sinusoidal samples. This correspondence proposes an efficient sensing scheme to obtain CS samples. They are sums

This article is devoted to the problem of multitarget tracking in the maritime environment using Bernoulli track-before-detect (TBD) filtering. Detection and tracking of weak targets in sea clutter using high-resolution airborne radar is notoriously challenging compared to classical target tracking problems. Furthermore, the measured amplitude in range–azimuth cells that are in the vicinity of closely

In this article, autonomous ground vehicle (AGV) path planning is considered. The AGV is assumed to be equipped with receivers capable of producing pseudorange measurements to overhead global navigation satellite systems (GNSS) satellites and to cellular base stations in its environment. Parameters of the cellular pseudoranges related to the transmitter clock bias are estimated in an initialization

Data and signal authentication schemes are being proposed to address Global Navigation Satellite Systems' (GNSS) vulnerability to spoofing. Due to the low power of their signals, the bandwidth available for authentication in GNSS is scarce. Since delayed-disclosure protocols, e.g., TESLA (timed-efficient stream loss-tolerant authentication), are efficient in terms of bandwidth and robust to signal

The histogram-probabilistic multihypothesis tracker (H-PMHT) is an efficient, track-before-detect algorithm that can operate directly on detection surfaces such as data from a focal-plane array (FPA). It provides good performance for low computational cost but is sensitive to sensor parameter changes, e.g. number of channels, gain, normalization, etc. This is because H-PMHT interprets the measured

In the present age of high-density integrated circuits, radiation-induced adjacent multibit upsets (AMBUs) or clustered errors are very prominent in the configuration memory of static-random-access-memory-based field-programmable gate array (FPGA) devices. Radiated particles with high energy and low momentum may damage a group of adjacent logic cells and switches in reconfigurable devices, which can

A tightly coupled inertial navigation system (INS) aided by ambient signals of opportunity (SOPs) is developed. In this system, a navigating vehicle aids its onboard INS using pseudoranges drawn from terrestrial SOPs with unknown emitter positions and clock biases through an extended Kalman filter-based radio simultaneous localization and mapping (SLAM) framework. The SOP-aided INS uses both global

Finding codes for the desired autocorrelation function (ACF) based on phase-coded modulation waveforms has always been a popular research topic, and the relevant literature is abundant. However, the optimized ACF may not be obtained in band-limited hardware due to the extended spectral sidelobes generated by instantaneous phase changes. Polyphase-coded FM (PCFM) waveforms based on continuous phase

In this article, a novel finite-time approximation-free control scheme is proposed for the attitude tracking of quadrotor unmanned aerial vehicles. Prescribed performance functions are employed to transform the original attitude tracking problem into an alternative system stabilization problem. By incorporating a finite-time error compensation mechanism into the recursive control design, the finite-time

Binary code negation and reversal are known to leave the autocorrelation sequence unchanged. However, for some code lengths, there exist code pairs for which the mechanism behind shared autocorrelation is not so simple; these are called shared-autocorrelation (or shared-ACS) binary code pairs. They are useful for, among other things, constructing binary and quad-phase Golay pairs of longer lengths

This article presents a command limiting method for attitude protection on aerial vehicles equipped with rate control augmentation systems.The method is developed based on exponential potential functions. To avoid excessive corrections, a switched command limiting control law is proposed. Stability analysis is provided for the closed-loop system. Phase portrait analysis on a linear plant with the proposed

Optical wireless communication (OWC) has garnered significant importance to provide gigabit capacity links owing to its unique features. Free-space optics (FSO) communication, which is the term used for OWC in an outdoor scenario, is a good candidate to establish ground-to-satellite/satellite-to-ground links. Despite of many advantages, FSO communication in uplink is limited by the adverse effects

Constrained trajectory optimization has been a critical component in the development of advanced guidance and control systems. An improperly planned reference trajectory can be a main cause of poor online control performance. Due to the existence of various mission-related constraints, the feasible solution space of a trajectory optimization model may be restricted to a relatively narrow corridor,

In this article, we propose a hybrid conditional random field model based on complex-valued 3-D convolutional neural network (C3NN), named as HCRF-C3NN, for polarimetric synthetic aperture radar (PolSAR) image classification. HCRF-C3NN combines the modeling power of random fields with the representation-learning ability of deep learning model for PolSAR image. By C3NN, HCRF-C3NN exploits deep amplitude

In this article, an augmented subspace-based algorithm for detecting the direction of arrival (DOA) of signals is presented. In the developed scheme, a uniform circular antenna array with a full range of lateral capacity is first transformed into a uniform linear antenna array in which the steering matrix has a Vandermonde form. This kind of structure can be exploited to formulate computationally efficient

Estimating the signal transmitted by a noncooperating radar is of great use in radar countermeasures. In this article, we propose to improve the noise resilience of the radar signal estimation by constraining the estimate to be in a low-dimensional signal space. In particular, we focus on estimating nonlinear frequency modulated radar signals that have good target resolution characteristics. A flexible

This article presents the development of an autonomous flight control system for a small-scale unmanned helicopter based on an online adaptive learning-based observer and model predictive control (MPC). The adaptive learning-based observer provides an approximate dynamic inversion for solving the coupled dynamic problem. The discrete-time MPC (DMPC) uses a prediction process to obtain a stable model

Attitude estimation based on a magnetic and inertial measurement unit is popular in the areas of robotics, aerospace, and unmanned aerial vehicles. Nevertheless, the magnetometer is prone to external magnetic disturbance that deteriorates the state estimation. This article proposes a novel partial state update strategy in the extended Kalman filter (PS-EKF) by optimally solving the posteriori covariance

Sensitivity and performance of homodyne radar are notably improved if the phase noise terms of transmit and receive signals are correlated and canceled out by the receiver. However, in a bistatic setup with separate oscillators, this correlation is inherently not given. To achieve a good carrier phase and phase noise coherency, it is required to transmit a radio frequency (RF) reference, e.g., by using

A robust constant false alarm rate (RCFAR) detector based on bilateral-trimmed-statistics (BTS-RCFAR) with a closed-form solution is proposed. BTS-RCFAR aims at improving the detection performance in complex ocean scenes such as the multiple-target environment, off-shore, oil-spilled ocean area, etc. In these circumstances, the clutter samples are often contaminated by the outliers. Consequently, the

Space missions exploiting small satellite networks with a use of software-defined radio (SDR) and advanced random access (RA) protocols have attracted an increased amount of attentions given their low costs, low latency levels, low complexity, and yet competitive data rates for global network services. In this article, we derive a mathematical model to demonstrate the reliability of a small satellite

A hierarchical clustering architecture is proposed to deal with the problem of jamming environment classification when multiple noise-like jammers are possibly present. Assuming the availability of clutter-free multichannel data, a two-level hierarchical procedure is devised to unveil the presence of clusters containing range cells experiencing the same jamming interference as the cell under test.

In this article, an observer-based adaptive hybrid attitude controller is presented that overcomes the topological obstructions associated with the global attitude stabilization. This hybrid controller consists of two major parts: an adaptive trimodal hybrid controller to eliminate $unwinding$ phenomenon, and a centrally synergistic potential function. In the adaptive trimodal hybrid controller, the

Sensor registration is an important problem that must be considered when attempting to perform any kind of data fusion in multimodal, multisensor target tracking. In this multiple target tracking (MTT) application, any inaccuracies in the registration can lead to false tracks being created, and tracks of true targets being stopped prematurely. This article introduces a method for simultaneously tracking

Over the last decade, there has been an increase in air transportation, which has raised awareness to provide necessary procedures to respond to air transportation demands and reduce delay costs. One such procedure, “performance-based navigation (PBN),” currently studied, is expected to increase the airspace capacity based on aircraft's individual performances. This research describes an efficient

The thermal modeling of small satellites (up to 100 kg) is crucial for predicting and managing their operation, and may present significant differences when compared to the thermal modeling carried out in relation to larger spacecraft. In this article, the modeling of their solar panels is underlined as one of these differences. The efficiency of spacecraft solar panels is affected by three main variables:

Leveraging the benefits of the multiobjective particle swarm optimization (PSO) technique, we introduce a new concept of adaptive strictly negative imaginary (SNI) controllers. The proposed adaptive control systems are specifically designed to minimize a certain performance index, representing the objective of our control design, which is to obtain a stable, robust, and responsive 3-D tracking of the

The weather conditions affect the approach and departure routings of aircraft. The detection of flight status of aircraft faces two major issues under adverse weather conditions. They are how to select an approximate and effective feature combination from different flight parameters and how to identify the status of an aircraft via a reasonable flight parameter combination. This article presents a

The pole-placement issue for linear multi-input multi-output (MIMO) dynamic systems with uncertain parameters has been addressed in this article. A static feedback matrix has been designed for minimizing variances of closed-loop poles (CLPs) and for assigning poles to the nominal system at the desired places. It is assumed that the joint probability density function (PDF) of uncertain parameters is known

In this paper an energy optimal dynamic attitude for a solar-powered aircraft is determined and implemented using the finite-time sliding mode approach. A nonlinear constrained optimization technique has been considered to determine the optimal attitude of the aircraft for given a geographical location, solar position, heading direction and other flight conditions for clear sky conditions. The optimization

The design of multitarget rendezvous missions requires a method to quickly and accurately approximate the optimal transfer between any two rendezvous targets. In this article, an artificial neural-network-based method is proposed for the rapid approximation of optimal perturbed long-duration impulsive transfers. The relationship between the optimal transfer velocity increments and the initial right

This article presents an adaptive waveform design method using multitone sinusoidal frequency modulation (MTSFM). The MTSFM waveform's modulation function is represented as a finite Fourier series expansion. The Fourier coefficients are utilized as a discrete set of design parameters. These design parameters can be modified to shape the spectrum, auto-correlation function (ACF), and ambiguity function

In this article, a finite-time control scheme is proposed for a quadrotor unmanned aerial vehicle (UAV) with external disturbance. First, a finite-time disturbance observer is designed to cope with external disturbance. Then, a nonsingular terminal sliding-mode control scheme is developed, which avoids singularity problem of conventional terminal sliding-mode control. By Lyapunov stability theory,

A deep neural network (DNN) is used for achieving subpulse resolution in noncoherent stepped frequency waveform radar. The tradeoff between high resolution and long range in radar systems is often addressed using pulse compression, allowing both long pulses and high resolution by increasing the pulse bandwidth. This typically requires a coherent radar. In this article we present a deep learning-based

Recent publications have investigated and demonstrated new digital modulation techniques that allow realization of orthogonal frequency division multiplexing (OFDM) radar with relatively low hardware effort. This is especially interesting as the digitally defined signals offer additional freedom for multiplexing schemes of multiple-input multiple-output (MIMO) radar sensors. MIMO radar sensors rely

This article presents a computationally efficient, fixed complexity algorithm for estimating the angle of arrival of a radio frequency signal that impinges on a sparse linear array of sensors. The likelihood function for the bearing estimation problem is reduced to an inhomogeneous Diophantine approximation problem involving an unknown set of integer multiples of $2\pi$ . In solving for the integers

Azimuthal centrosymmetry in an array grid is typically associated with arrays that are circular, concentric, cylindrical, spherical, or hemispherical. However, a recently proposed alternative combines an azimuthal circular array with a linear vertical array. For this elegantly simple new array grid's use in the direction-of-arrival estimation, this article advances array-design insights to meet a given

The article addresses the fully distributed time-varying formation control problem for multiple missiles involving uncertainties. An adaptive control protocol is developed for the missiles, which includes uncertainties in the flight dynamics, while the adaptive control protocol does not require global information of the network missile system. Global formation flight stability is proven via the Lyapunov

In this article, a robust constant false alarm rate detector (CFARD) is proposed for dense outlier situations such as the presence of high-density interfering targets within the reference window. Harmonic mean mitigates the impact of large outliers better than the arithmetic mean. We propose a CFARD called censored harmonic averaging (CHA)-CFARD, by using the modified harmonic averaging instead of

Adaptive estimation of optimal combination weights for partial-diffusion Kalman filtering together with its mean convergence and stability analysis is proposed here. The simulations confirm its superior performance compared with the existing combiners. Sensor networks with limited accessible power highly benefit from this design.