Cooperative localization (also known as sensor network localization) using received signal strength (RSS) measurements when the source transmit powers are different and unknown is investigated. Previous studies were based on assumption that of nodes same perfectly which not practical. In this paper, considered nuisance parameters estimated along with locations. The corresponding Cramér-Rao lower bound (CRLB) problem derived. To find maximum likelihood (ML) estimator, it necessary to solve a...

Emerging communication network applications including fifth-generation (5G) cellular and the Internet-of-Things (IoT) will almost certainly require location information at as many nodes possible. Given energy requirements lack of indoor coverage Global Positioning System (GPS), collaborative localization appears to be a powerful tool for such networks. In this paper, we survey state art in with an eye toward 5G IoT applications. particular, discuss theoretical limits, algorithms, practical...

In this letter, cooperative source localization using range-based measurements in severe non-line-of-sight (NLOS) environments is studied. The accuracy of can significantly degrade indoor and dense environments, where the majority connections are NLOS. Cooperative highly beneficial such by improving performance considerably. However, NLOS still must be handled properly. work, a novel algorithm with ability to mitigate propagation based on semidefinite programming (SDP) derived. It assumed...

This correspondence studies the received signal strength-based localization problem when transmit power or path-loss exponent is unknown. The corresponding maximum-likelihood estimator (MLE) poses a difficult nonconvex optimization problem. To avoid difficulty in solving MLE, we use suitable approximations and formulate as general trust region subproblem, which can be solved exactly under mild conditions. Simulation results show promising performance for proposed methods, also have...

In this paper, cooperative sensor localization using asynchronous time-of-arrival measurements is investigated. It well known that performance in wireless networks time-based ranging or pseudo-ranging methods greatly affected by the accuracy of timing synchronization between nodes involved estimation. Commonly, original estimation problem broken down into two subproblems, and problem, what as a two-step approach. However, joint considered examined for use networks. discussed cooperation...

Received signal strength (RSS)-based single source localization when there is not a prior knowledge about the transmit power of investigated. Because nonconvex behavior maximum likelihood (ML) estimator, convoluted computations are required to achieve its global minimum. Therefore, we propose novel semidefinite programming (SDP) approach by approximating ML problem convex optimization which can be solved very efficiently. Computer simulations show that our proposed SDP has remarkable...

In this work, time-of-arrival (TOA)-based wireless sensor localization in non-line-of-sight (NLOS) environments is investigated. such environments, the accuracy of techniques significantly degraded. While previous work often assumes some knowledge NLOS environment, we assume that estimator knows neither which connections are nor distribution errors. It shown maximum likelihood using only LOS provides a lower bound on estimation accuracy. Furthermore, novel mitigation technique based...

Intelligent Transportation Systems (ITS) have emerged to utilize different technologies enhance the performance and quality of transportation networks. Many applications ITS need a highly accurate location information from vehicles in network. The Global Positioning System (GPS) is most common accessible technique for vehicle localization. However, conventional localization techniques which mostly rely on GPS technology are not able provide reliable positioning accuracy all situations. This...

In this paper, asynchronous wireless source localization using time-of-arrival (TOA) measurements is studied. TOA localization, the travel time of signal between node and anchor nodes measured used to estimate range. synchronous networks, know when starts transmission. however, transmit unknown have a positive bias due synchronization error which could lead large error. One way tackle problem use time-difference-of-arrival (TDOA) do not depend on transmission time. However, in work, applying...

This paper represents a preliminary study of cooperative positioning in Long Term Evolution (LTE) systems. Many applications, such as location-based services and Enhanced 911 (E911), require that the locations users cellular system are available. The global navigation satellite (GNSS) is most accessible systems which widely used cellphones. However, poor operation indoor dense environments leads us to use localization backup solution. In localization, determined via measurements obtained...

The accuracy of localization is highly degraded in indoor and harsh environments where source nodes either do not have connections with a sufficient number anchor due to strong attenuation or very poor range estimates NLOS propagation. Cooperative technique which the communicate only nodes, but also each other. Hence, can collect several additional measurements significantly improve performance. Although many studies examined NLOS-degraded static node noncooperative networks, others impact...

In this paper, the bearing-only target localization problem when observer positions are subject to error is investigated. problem, angle of arrival transmitted signal between and used estimate position. It assumed that not only bearing measurements corrupted by noise but also exact position available estimator. The accuracy estimated location depends on reliability information from Therefore, previously published algorithms considering measurement do meet expected performance error. maximum...

Cooperative time-of-arrival-based sensor localization in a non-line-of-sight (NLOS) environment is investigated. plays an important role indoor networks where GPS limited. However, suffer from NLOS propagation which degrades accuracy significantly. In this paper, we assume that the estimator able to discriminate connections line-of-sight (LOS) connections. We introduce novel semidefinite programming (SDP) approach for cooperative exploits enhance of localization. The performance proposed...

Wireless sensor localization using received signal strength (RSS) measurements is investigated in this paper. Most studies for RSS assume that the shadowing components are uncorrelated. However paper, we spatially correlated. Under condition, it can be shown accuracy improved if correlation among links taken into consideration. Avoiding maximum likelihood (ML) convergence problem, derive a novel semidefinite programming (SDP) approach by converting corresponding noncovex ML estimator convex...

In this paper, asynchronous sensor localization using time-of-arrival (TOA) measurements is studied. Accurate TOA-based requires perfect timing synchronization between the source and anchor nodes. networks, nodes are assumed to be synchronized, while clock of node needs synchronized with those Although typically performed separately, in work a joint framework considered, as it expected provide significant improvement over two-step approaches. The parameters (clock offset skew) estimated...

In this paper, cooperative positioning for Long Term Evolution (LTE) cellular systems using Radio Frequency Pattern Matching (RFPM) is studied. Having the locations of users in a system supports many applications such as location-based services and E911. Although Global Positioning System (GPS) can be found every smartphone, its poor performance indoor dense environments encourages development network-based solutions. Cellular localization has emerged which user determined by measurements...

This paper studies cooperative user positioning using uplink time-difference-of-arrival (UTDOA) measurements for 4G Long Term Evolution (LTE) cellular networks. Many applications in a network, such as location-based services and E-911, rely on accurate locations of users the network. Although Global Positioning System (GPS) is widely used cellphones, their poor localization performance indoor dense environments leads to emergence network-based techniques backup solution. In techniques, are...

In this paper, joint sensor synchronization and localization using time-of-arrival measurements is studied. wireless networks, the accuracy of clock among nodes has a great impact on performance time-based ranging methods. The clocks anchor are typically synchronized with each other, while those source must be nodes. Each node its own characterized by offset skew. Synchronization process determining these parameters for node, estimating location. Generally, estimation problem broken down...

In this paper, the problem of target tracking in non-line-of-sight (NLOS) environments is investigated. Target has many commercial, civilian, and military applications. The accuracy highly affected indoor where majority connections are NLOS. A novel estimator based on semidefinite programming (SDP) with ability to mitigate NLOS propagation derived. Requiring no statistical information about propagation, proposed SDP algorithm estimates biases jointly location velocity target. performance...

In this paper, the problem of mobile tracking in dense environments is studied. The Global Positioning System (GPS) most accessible positioning technique. However, GPS does not work properly indoor and areas, as receiver typically have access to a sufficient number line-of-sight satellites. Therefore, localization these networks can be alternatively done by using measurements collected within network without aid any external resources (e.g., GPS). includes several static reference nodes...

A novel multilayer neural network model, called artificial synaptic network, was designed and implemented for single sensor localization with time-of-arrival (TOA) measurements. In the TOA problem, location of a source is estimated based on its distance from number anchor sensors. The measured values are noisy estimator should be able to handle different amounts noise. Three models: proposed multi-layer perceptron generalized radial basis functions were applied problem. performance models...

In this paper, joint sensor localization and synchronization in non-cooperative wireless networks (WSNs) using time-of-arrival (TOA) measurements is studied. addition to zero-mean errors TOA we consider other sources of error such as non-line-of-sight (NLOS) propagation anchor uncertainty make our technique more useful practice, where the presence these inevitable. The proposed based on semi-definite programming (SDP) relaxation which can be solved polynomial time guarantees convergence...

Full-dimension MIMO (FD-MIMO) using planar active antenna systems (AAS) is considered a critical technology for fifth-generation (5G) cellular to improve network capacity.An AAS typically subject hardware impairments that negatively impact capacity.Hence, this article focuses on cause phase and magnitude errors between radio frequency (RF) chains shows why they are particularly difficult avoid in practical AAS.Although previous investigations show these degrade performance, not useful...

It is well-known that non-line-of-sight (NLOS) propagation degrades the accuracy of localization in indoor and harsh environments. In such environments, source nodes either do not have connections with a sufficient number anchor due to strong attenuation or very poor range estimates NLOS propagation. Cooperative localization, which node communicates both other nodes, can benefit scenarios by providing additional measurements significantly improve performance. While most earlier works studied...

Passive localization of a radio emitter on the ground is an important subject in military and security contexts. In passive localization, time-difference-of-arrival (TDOA) frequency-difference-of-arrival (FDOA) combination received signals can be used to determine location emitter. The performance TDOA/FDOA estimation using single-input-single-output (SISO) well-known literature. However, multiple-input-multiple-output (MIMO) how they affect accuracy have not studied before. this paper, we...