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Tema ovog rada je bežično pozicioniranje pomoću Wi-Fi mreže. Prvi dio rada se bavi teorijskim dijelom opisivanja razvoja Wi-Fi-a, WLAN arhitekture i njezinih komponenata. Također, opisuje se problematika i funkcioniranje pozicioniranja u zatvorenim prostorima te IPS sustava. Zatim, slijedi usporedba različitih tehnologija, tehnika i algoritama za pozicioniranje u zatvorenom prostoru. Zadnji dio rada se odnosi na provedbu mjerenja snage signala pet AP-ova postavljenih na hodniku u zgradi Fakulteta elektrotehnike, računarstva i informacijskih tehnologija Osijek – FERIT. Svrha mjerenja je bila izmjeriti mobilnom aplikacijom u odabranim referentnim točkama duž cijelog hodnika snagu signala svakog pojedinog AP-a u datoj točki. Na temelju prikupljenih podataka i uz pomoć Cell-ID metode pokušala se procijeniti lokacija odabranih točaka i usporediti sa stvarnom lokacijom koja je poznata. Prikupljeni podaci su prikazani tablično i pomoću grafova, te su opisana zapažanja i zaključci. The topic of this thesis is wireless positioning using a Wi-Fi network. The first part of the paper deals with the theoretical part of describing the development of Wi-Fi, WLAN architecture and its components. Also, the problems and functioning of positioning indoors and IPS system are described. Then, a comparison of different technologies, techniques and algorithms for indoor positioning follows. The last part of the paper refers to the implementation of signal strength measurements of five APs installed in the hallway in the building of the Faculty of Electrical Engineering, Computing and Information Technology Osijek - FERIT. The purpose of the measurement was to measure the signal strength of each individual AP at a given point with a mobile application at selected reference points along the entire corridor. Based on the collected data and using the Cell-ID method, an attempt was made to estimate the location of the selected points and compare them with the actual location known. The collected data are presented in tables and graphs, and observations and conclusions are described.

International audience; The Cell-ID positioning technique is usually implemented on cellular networks to locate mobile phones according to the cell identification code forwarded by the Base Transceiver Station (BTS). The user is then assumed to be located at the same coordinate position as the BTS. However, this simple positioning method, also used in indoor location systems with WiFi or RFID technologies, suffers from a lack of accuracy due to the size and the density of cells. In this paper we propose an indoor positioning system in underground mine tunnels based on the cell-ID method and the innovative Visible Light Communications (VLC) technology. Unlike previous technologies, it is possible to increase the position accuracy in controlling the number of light sources, i.e. the distribution of overlapping cells. As a result, self-adaptive positioning systems could be developed, where the switch on (or off) of the individual LEDs is determined according to the precision required by the application. We present an analytical model for such systems, based on Euclidean geometry equations. It is shown that the maximum position error in each cell may be fixed to obtain a positioning system with a constant accuracy. Finally, an application of this system is given to locate people or machinery in underground mine tunnels.

International audience; The Cell-ID positioning technique is usually implemented on cellular networks to locate mobile phones according to the cell identification code forwarded by the Base Transceiver Station (BTS). The user is then assumed to be located at the same coordinate position as the BTS. However, this simple positioning method, also used in indoor location systems with WiFi or RFID technologies, suffers from a lack of accuracy due to the size and the density of cells. In this paper we propose an indoor positioning system in underground mine tunnels based on the cell-ID method and the innovative Visible Light Communications (VLC) technology. Unlike previous technologies, it is possible to increase the position accuracy in controlling the number of light sources, i.e. the distribution of overlapping cells. As a result, self-adaptive positioning systems could be developed, where the switch on (or off) of the individual LEDs is determined according to the precision required by the application. We present an analytical model for such systems, based on Euclidean geometry equations. It is shown that the maximum position error in each cell may be fixed to obtain a positioning system with a constant accuracy. Finally, an application of this system is given to locate people or machinery in underground mine tunnels.

In this paper we evaluate user-equipment (UE) positioning performance of three cluster-based RF fingerprinting methods using LTE and WLAN signals. Real-life LTE and WLAN data were collected for the evaluation purpose using consumer cellular-mobile handset utilizing ‘Nemo Handy’ drive test software tool. Test results of cluster-based methods were compared to the conventional grid-based RF fingerprinting. The cluster-based methods do not require grid-cell layout and training signature formation as compared to the gridbased method. They utilize LTE cell-ID searching technique to reduce the search space for clustering operation. Thus UE position estimation is done in short time with less computational cost. Among the cluster-based methods Agglomerative Hierarchical Cluster based RF fingerprinting provided best positioning accuracy using a single LTE and six WLAN signal strengths. This method showed an improvement of 42.3 % and 39.8 % in the 68th percentile and 95th percentile of positioning error (PE) over the grid-based RF fingerprinting. peerReviewed

Today, positioning with GPS and the advantages this entails are almost infinitive, which means that the technology can be utilized in a variety of applications. Unfortunately, there exists a lot of limitations in conjunction with the signals from the GPS can’t reach inside e.g. buildings or underground. This means that an alternative solution that works indoors needs to be developed. The report presents the four most common radio-based technologies, Bluetooth,Wi-Fi, UWB and RFID, which can be used to determine a position. These all have different advantages in cost, accuracy and latency, which means that there exist a number of different applications. The radio-based methods use the measurement techniques, RSSI, TOA, TDOA, Cell-ID, PD or AOA to gather data. The choice of measurement technique is mainly dependent of which radio-based method being used, since their accuracy depends on the quality of the measurements and the size of the detection area, which means that all measurement techniques have different advantages and disadvantages. The measurement data is processed with one of the positioning methods, LS, NLS, ML, Cell-ID, WC or FP, to estimate a position. The choice of positioning method also depends on the quality of the measurements in combination with the size of the detection area. To evaluate the different radio-based methods together with measurement techniques and positioning methods, accuracy, latency and cost are being compared. This is used as the basis for the choice of positioning method, since a general solution can get summarized by finding the least expensive approach which can estimate an unknown position with sufficiently high accuracy.

Today the need to locate people, objects or things have a growing demand for what Location Services are becoming a very popular service for mobile phone users, for informational purposes, security, entertainment, etc. In the context of positioning methods and general methods used in UMTS networks, this paper attempts to summarize and analyze the different positioning techniques commonly used in Location Services. The methods used in UMTS are: Cell-ID or cell coverage, OTDoA-IPDL or Observed Time Difference of Arrival, and Assisted GPS. From the standpoint of analytical and mathematical, we have proposed an algorithm in Matlab and Simulink to simulate the different methods and the technique used, graphically, thorough and understandable, especially as they intersect curves, circles and spheres, for find the position of the target. With this simulation we try to understand clearly the process of positioning and finally make a comparison between these methods.

There is some skepticism regarding the practical implementation of a tracking system that depends on cell identification (Cell-ID) information. This pessimism is due to the fact that tracking systems are known to require high positioning accuracy, while Cell-ID positioning is known as being "low accuracy" positing technique. However, using the Cell-IDs in a different way (a novel approach) than in current positioning will allow the implementation of a tracking system capable of providing sufficient positioning accuracy for many locationdependent applications.

Šio darbo tikslas – ištirti objektų pozicijų nustatymo Cell-ID metodu paklaidas. Darbe pateikiama esamų sprendimų analizė, pristatoma GSM/3G tinklo celių aprėpčių modelio įvertinimo metodika, jos pagrindu sukurta programinė įranga, pateikiami programinės įrangos kokybės ir eksperimentinis tyrimai. Atlikta vietos nustatymo Cell-ID metodu esamų sprendimų analizė parodė, kad GSM/3G tinklo celių aprėpčių teritorijų skaičiavimo modeliai yra netikslūs. Todėl operatoriai yra suinteresuoti gauti vietos nustatymo paklaidų įvertinimą. Sudaryta GSM/3G tinklo celių aprėpčių modelio įvertinimo metodika pagrįsta celių aprėpčių patikrinimu naudojant GPS sistemos duomenis. Remiantis aprėpčių modelio įvertinimo metodika sukurta GSM/3G tinklo celių aprėpčių modelio įvertinimo programinės įrangos kokybė yra aukšta. Programinė įranga išbandyta realiomis sąlygomis ir gauti vietos nustatymo paklaidų skirstiniai. Eksperimentinio tyrimo rezultatai parodė, kad kai kurie operatoriai užtikrina iki 20 procentų tikslesnę vietos nustatymo paklaidą GSM/3G tinklo celių aprėpčių atžvilgiu. GSM/3G tinklo celių aprėpčių modelio įvertinimo sistema įdiegta užsakovo įmonėje., The work investigates inaccuracies of objects positions’ location based on Cell-ID method. The work covers analysis of present solutions, presents the developed methodology of evaluation of cells‘ coverages‘ model in GSM/3G network, software which was designed and implemented according to the methodology, experimental research and research of the quality of the developed software. The analysis of present solutions of location based on Cell-ID method showed that calculating models of cells‘ coverages in GSM/3G network are inaccurate. Therefore operators are concerned to get an evaluation of location inaccuracies. The developed methodology is based on the verification of cells’ coverages using the data of GPS system. The quality of the developed software of evaluation of cells’ coverages’ model in GSM/3G network based on methodology of evaluation of cells’ coverages’ model is estimated as high. The developed software was tried in real conditions and distributions of location inaccuracies are received. The results of the experimental research showed that some operators provide approximately 20 percents more accurate location inaccuracy with regard to cells‘ coverages in GSM/3G network. The software of evaluation of cells‘ coverages‘ model in GSM/3G network is installed in the customer‘s company.

The majority of existing GSM positioning techniques can be described as either costly or with limited performance. Basic GSM positioning techniques Cell-ID and Cell-ID+TA can be upgraded to decrease positioning error. We introduce a new location technique E-CIDTA that requires no additional infrastructure. A probabilistic approach is used to model TA parameters behaviour over distance. These models are applied to the E-CIDTA algorithm to estimate the location of a mobile user. Finally, we evaluate and discuss the performance of E-CIDTA and compare it to other positioning techniques.