New trends in radio network positioning

vi.uni-klu.ac.at

After his master thesis, he joined the Institute of Communications Engineering, Group of Positioning and Location-based Services also at the Leibniz University of Hannover, where he is now working towards his PhD thesis in the field of mobile positioning in wireless networks. The research interests of Mr. Khalaf-Allah include positioning and tracking technologies, data fusion and filtering techniques. He has also worked as a consulting engineer for an automotive competence center in the field of GPS/INS vehicle navigation. Mr. Khalaf-Allah is a member of IEEE and VDE (German Association for Electrical, Electronic & Information Technologies). Dr. Kyandoghere Kyamakya obtained his master of science (Ingénieur Civil) in Electrical Engineering at the University of Kinshasa in 1990. In 1999 he completed his doctorate in Electrical Engineering at the Fernuniversität Hagen in Germany. He then spent two years of postdoc research at the Leibniz University of Hannover in the field of "Mobility Management in Wireless Networks and Location Based Services".

IEEE Signal Processing Magazine, 2000

2007

This paper describes the current efforts to develop an open source, privacy sensitive, location determination software component for mobile devices. Currently in mobile computing, the ability of a mobile device to determine its own location is becoming increasingly desirable as the usefulness of such a feature enhances many commercial applications. There have been numerous attempts to achieve this from both the network positioning perspective and also from the wireless beacon angle not to mention the integration of GPS into mobile devices. There are two important aspects to consider when using such a system which are privacy and cost. This paper describes the development of a software component that is sensitive to these issues. The ICiNG Location Client (ILC) is based on some pioneering work carried out by the Place Lab Project at Intel. (Hightower et al., 2006) The ILC advances this research to make it available on mobile devices and attempts to integrate GSM, WiFi, Bluetooth and ...

The huge success of location-aware applications has called for the rapid development of an alternative positioning system to the global positioning system (GPS) for indoor localization based on existing technologies, such as 802.11 wireless networks. This paper proposes the Wireless MAC Processor Positioning System (WMPS), which is a localization system running on off-the-shelf 802.11 Access Points and based on the time-of-flight ranging of users' standard terminals. This paper proves through extensive experiments that the propagation delays can be measured with the accuracy required by indoor applications despite the different noise components that can affect the result: latencies of the hardware transreceivers, multipath, ACK jitters and timer quantization. Key to this solution is the choice of the Wireless MAC Processor architecture, which enables a straightforward implementation of the ranging subsystem directly inside the commercial cards without affecting the basic DCF cha...

Recent advancement in wireless networks and systems has seen the rise of localization techniques as a worthwhile and cost-effective basis for novel services. These location based services (LBSs) have been more and more beneficial and money-making for telecommunications operators and companies. Various LBSs can be offered to the user such as tracking, advertisement, security, and management. Wireless networks themselves may benefit from localization information to enhance the performances of the different network layers. Location based routing, synchronization, interference cancellation are some examples of fields where location information can be fruitful. Two main tasks a localization system must be able to do: measurement of locationdependent parameters (LDPs) (e.g. time of arrival -TOA-, time difference of arrival -TDOA-, and received signal strength indicator -RSSI-) and estimation of position using location estimation techniques. The main goal of this dissertation is the study of different location estimation techniques. Estimation and measurement of LDPs are also investigated using a provided measurements campaign in order to have a complete understanding of localization field.

In this paper we present a distributed positioning system for indoor environments based on a network of compact independent anchor nodes operating as specialized WiFi access points. Each node is built with component-off-the-shelves and it is capable of standard IEEE 802.11 connectivity at 2.45GHz. The enabling technology for the localization is the Switched Beam Antenna (SBA) equipped in each node, which permits a space division multiple access at network-level. The positional information is the result of a maximum likeli- hood estimation driven by the expected signal space partition of the constellation, and it is tolerant to noisy power measurements, such as Received Signal Strength Indicator, thanks to angular filtering capability of the SBA, which in addition operates in circular polarization. Experimental validations demonstrate the performance of a 3-anchors network, operating within the IEEE 802.11 protocol, monitoring a single nomadic node inside a 7m 2 indoor square area. It results that 68% of the square area is covered with a localization error below 50cm, with a mean error of 47cm. Inside the triangular mesh defined by the three anchors, the mean error drops to 39cm, with 88% of the area being below 50cm. In addition, the maximum error is always below 77cm.

2011

Nowadays, several positioning systems are available for outdoor localization, such as the global positioning system (GPS), assisted GPS (A-GPS), and other techniques working on cellular networks, for example, Time of Arrival (TOA), Angle of Arrival (AOA) and Time Difference of Arrival (TDOA).However, with the increasing use of mobile computing devices and an expansion of wireless local area networks (WLANs), there is a growing interest in indoor wireless positioning systems based on the WLAN infrastructure. Wireless positioning systems (WPS) based on this infrastructure can be used for outdoor / indoor localization to determine the position of mobile users. An important factor in achieving this is to minimize and simplify the instructions that the mobile station (MS) has to execute in the location determination process. Finding an effective location estimation technique to facilitate processing data is the main focuses in this paper. Therefore, in the wireless propagation environmen...

EURASIP Journal on Advances in Signal Processing, 2006

received the Ph.D. degree in 1995 with distinction and the German Habilitation degree in 2000, both from Gerhard Mercator University Duisburg and in electrical engineering. In the summer of 2005 he joined Stanford's Smart Antenna Research Group (SARG) as a Visiting Professor. Now he holds a Chair on communication systems at the University of Hannover, Germany, and is the Founder of the spin-off company mimoOn GmbH. He has published more than 100 papers and has coedited four books on ultra-wideband and smart antenna systems. He is the founding Editor-in-Chief of the IEEE Signal Processing Society E-Letter. His research interest focuses on applied signal processing with emphasis on multiantenna systems, especially its applicability to ultra-wideband systems.

Satellite Positioning - Methods, Models and Applications, 2015

Lecture Notes in Computer Science, 2007

This paper describes the current efforts to develop an open source, privacy sensitive, location determination software component for mobile devices. Currently in mobile computing, the ability of a mobile device to determine its own location is becoming increasingly desirable as the usefulness of such a feature enhances many commercial applications. There have been numerous attempts to achieve this from both the network positioning perspective and also from the wireless beacon angle not to mention the integration of GPS into mobile devices. There are two important aspects to consider when using such a system which are privacy and cost. This paper describes the development of a software component that is sensitive to these issues. The ICiNG Location Client (ILC) is based on some pioneering work carried out by the Place Lab Project at Intel. (Hightower et al., 2006) The ILC advances this research to make it available on mobile devices and attempts to integrate GSM, WiFi, Bluetooth and GPS positioning into one positioning module. An outline of the ILC's design is given and some of the obstacles encountered during its development are described.

This paper provides an overview about the results of indoor and outdoor ranging measurements by radio based position estimation in the 2.4 GHz-band. A commercial wide band location system represents the basis therefore. Position estimation is based on distance measurements by means of a time of arrival (TOA) ranging method. The linear least square (LS) estimator is used for computing position estimation by transforming the original nonlinear LS problem into a linear one. The obtained accuracy has to be verified for telematics applications, influencing the coordination of road, rail, maritime and air transport. In these fields there are many special applications for example selective detection of a rail track, lane selective localization in automotive applications. The paper concludes with a prospect about further steps concerning the estimation algorithm enhancement.

2015 IEEE International Conference on Signal Processing, Informatics, Communication and Energy Systems (SPICES), 2015

Positioning techniques are known in a wide variety of wireless radio access technologies. Traditionally, Global Positioning System (GPS) is the most popular outdoor positioning system. Localization also exists in mobile networks such as Global System for Mobile communications (GSM). Recently, Wireless Local Area Networks (WLAN) become widely deployed, and they are also used for localizing wireless-enabled clients. Many techniques are used to estimate client position in a wireless network. They are based on the characteristics of the received wireless signals: power, time or angle of arrival. In addition, hybrid positioning techniques make use of the collaboration between different wireless radio access technologies existing in the same geographical area. Client positioning allows the introduction of numerous services like real-time tracking, security alerts, informational services and entertainment applications. Such services are known as Location Based Services (LBS), and they are useful in both commerce and security sectors. In this paper, we explain the principles behind positioning techniques used in satellite networks, mobile networks and Wireless Local Area Networks. We also describe hybrid localization methods that exploit the coexistence of several radio access technologies in the same region, and we classify the location based services into several categories. When localization accuracy is improved, positiondependant services become more robust and efficient, and user satisfaction increases.

2011

During the last years we witnessed an increasing interest in pervasive computing systems and applications. Ubiquitous computing environments provide multitudes of technologies seamlessly augmented with physical systems to aid users in everyday tasks. Accurate location awareness is of paramount importance in most pervasive applications. Numerous techniques for indoor localization based on IEEE 802.11, bluetooth, ultrasonic and vision technologies have been proposed. This thesis presents two di erent approaches for positioning. In the rst the IEEE 802.11 infrastructure is used and in the second computer vision is employed as the sensing modality. We propose a localization technique based on the generation of statistical ngerprints from signal strength measurements, that are collected from several access points (APs). A discretized grid-like form of the environment is considered and a signature at each cell of the grid is computed. At run time the system compares the signature at the u...

2011

This paper presents a reliable and accurate positioning method, which provides location estimates for the mobile user in a wireless network where IEEE802.11/WiFi, IEEE802.16/WiMAX, 3GPP LTE and Bluetooth wireless technologies are deployed. The developed data fusion algorithm utilises measurements and features such as Time of Arrival (TOA) and multiple input, multiple output (MIMO) antennas and wireless links between mobile users in order to enhance the positioning accuracy. Therefore, in the proposed concept of mobile user positioning is proposed and it is applied to hybrid wireless network environment. Results satisfy the FCC requirements for the network and mobile-centric positioning solution.

Radio Communications, 2010