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In this study, the optimal sensor placement problem for multi-source angle of arrival localisation is investigated. The authors adopt the A-optimality criterion, maximising the trace of Fisher information matrix, to determine the optimal sensor-target geometry under distance-dependent Gaussian noise model. A recursive representation of the Cramer-Rao lower bound is derived to recast the sensor placement problem into a sequential method, obtaining the optimal sensor geometries in a step by step manner. Note that the state-of-the-art methods are highly sensitive to the source location changes such that they should be relocated by any later changes in target geometries, which is practically... 

In this study, the optimal sensor placement problem for multi-source angle of arrival localisation is investigated. The authors adopt the A-optimality criterion, maximising the trace of Fisher information matrix, to determine the optimal sensor-target geometry under distance-dependent Gaussian noise model. A recursive representation of the Cramer-Rao lower bound is derived to recast the sensor placement problem into a sequential method, obtaining the optimal sensor geometries in a step by step manner. Note that the state-of-the-art methods are highly sensitive to the source location changes such that they should be relocated by any later changes in target geometries, which is practically... 

This paper presents a new approach to sensor placement strategy in emitter localization problem which is based on Time Difference of Arrival (TDOA) measurements. The advantage of this method is its flexibility and capability of positioning sensors in constrained or non-stationary situations in which the positions of the sensors are restricted to certain portions of the space and/or needed to be changed repeatedly. The validity of the proposed algorithm is assessed by three different simulation scenarios and the results verify its proper operation  

This study presents a new approach to sensor placement strategy in emitter localisation problems based on time difference of arrival measurements. The method addresses a flexible procedure which is capable of positioning the sensors in constrained environments or non-stationary situations where the positions of the sensors are restricted to certain parts of the space and/or need to be changed repeatedly. This method is sequential and has lower computation burden compared to other methods. The validity of the proposed algorithm is assessed by many different numerical scenarios and the results verify its proper operation. © The Institution of Engineering and Technology 2017  

The problem of sensor placement for passive source localization under the non-line of sight signal propagation is considered in this paper. To this end, first we derive the Cramer-Rao lower bound for the time of arrival based source localization under non-line of sight conditions. Then, the optimal arrangement of sensors to achieve this lower bound is obtained in the two important cases with all of the receivers being non line of sight ones in the first case and a combination of line of sight and non-line of sight receivers in the 2nd case. © 2018 IEEE  

Localization of an emitting or reflecting target is one of the most important issues in a wide range of applications including radar, sonar, wireless communication and sensor networks. Due to significant effect on the positioning accuracy, designing the optimal sensor-target geometry has been considered as an important problem in the localization literature. The existing sensor placement methods mainly solve the problem in the cases without any constraints on the sensors locations. In the realistic scenarios, however, the sensors cannot be placed simply in arbitrary locations due to such constraints as the geographical limitations, communication problems between the sensor pairs and the... 

The sensor-source geometry has a significant effect on accuracy of source localization problems. In a sensor placement problem, one attempts to optimally place the sensors in the surveillance area so as to optimize a performance criterion. Sensor placement methods mainly solve the associated problems without taking any specific constraint on permissible location of sensors into account. In practical applications, however, possible location for deployment of the sensors are subject to such limitations as environmental, industrial, and communication constraints, which affects the optimal sensor-source geometry. In this article, we consider the problem of optimal sensor placement, based on time... 

Many modern industrialized systems such as aircrafts, rotating turbines, satellite booms, etc. cannot perform their desired tasks accurately if their uninhibited structural vibrations are not controlled properly. Structural health monitoring and online reliability calculations are emerging new means to handle system imposed uncertainties. As stochastic forcing are unavoidable, in most engineering systems, it is often needed to take them into the account for the control design process. In this research, smart material technology is utilized for structural health monitoring and control in order to keep the system in a reliable performance range. In this regard, a reliability-based cost... 

The Cramer-Rao lower bound for source localization based on Time Difference of Arrival and Frequency Difference of Arrival is investigated in this paper. The result is used for theoretical analysis of optimality in sensor placement. An optimal sensor-target geometry including sensors locations and velocities is presented and its properties is studied  

Voting logic or k out of p redundancy is widely used in safety systems to meet two key objectives: enhancing reliability and reducing spurious performance. Even so, in designing gas detector systems especially of flammable gas type, it is a common engineering practice to consider at least two different detection levels in addition to normal voting. Under such circumstances, the presence of gas is confirmed if sensed by two detectors at two different concentrations: one at a low level and another one in the same voting network at a high level. Existing formulations for optimal placement of gas detectors do not consider this type of voting. In this study, first the general form of multi-level... 

This paper presents a new framework for the optimal placement of actuators in uncertain dynamic networks. The objective is to select a subset of nodes from a set of potential actuator placements, such that the controllability of the network with norm-bounded perturbation is preserved over the entire uncertain region. Evaluation of robust controllability is known to be computationally intractable. The recent results of Babazadeh and Nobakhti (2016) are utilized to establish equivalent conditions for robust controllability of uncertain networks. It is shown that for a large class of dynamic systems, including undirected networks, the exact distance to uncontrollability is evaluated by solving... 

In this paper, we consider the problem of sensor placement for passive source localization under conditions where there are multiple sources and noise measurement is distance dependent. To this end, first we derive the Cramer-Rao bound for the angle of arrival (AOA) based source localization for distance-dependent noise model and existence of multiple sources. Then, the optimal arrangement of sensors to achieve this bound is obtained  

A major challenge in automatic irrigation of extensive agricultural fields is large scale soil moisture monitoring. Proper orthogonal decomposition (POD) is a widespread data-driven dimension reduction technique which can be combined with QR pivoting method for estimation of high-dimensional signals and optimal sensor placement. However, it requires computation of tailored basis functions which should be extracted from known training data. This is feasible for problems with constant features such as face recognition. However, using fixed bases (and probably fixed sensor selection) may not be an appropriate approach for estimation of signals with time-variant features. This paper demonstrates... 

This paper addresses the optimality of Network topology for localization purposes when measurements are range-only. Localization procedures based on TOA and TDOA range measurements are considered in this paper. As of now, the optimal placement of fixed terminals to locate mobile terminals has been studied based on Cramer-Rao Lower Bound (CRLB). CRLB is a universal bound on the variance of a general unbiased estimator and therefore is not dependent to the estimator and methods of localization. Here we introduce another algorithm dependent criterion, based on perturbation theory of linear equations. Different optimal topologies are presented using the new criterion. These optimal topologies,... 

Although the main objective of utilizing gas detection systems is risk reduction by detecting high-risk scenarios, the majority of published placement procedures do not address the risk concept quantitatively. To include this concept, a risk-based methodology is proposed that consists of four key steps: input data, dispersion analysis, risk analysis, and optimization. In the first step, a set of release scenarios are defined and required data, including frequency of release, wind rose, and grid set, are provided. In the dispersion analysis step, the set of scenarios is simulated using a dispersion simulation tool and the ability of grid points to detect any scenario is stored in a binary...