In this thesis, a complete localization system using asynchronous time difference of arrival (A-TDOA) technique has been thoroughly studied from concept to implementation. The work spans from a proposal of a new A-TDOA system deployment and modeling, through a derivation of the achievable estimation bound, to estimation algorithms development, to a hardware realization, and ultimately to measurements conducted in realistic radio environments. The research begins with a new deployment of an A-TDOA localization system. Compared to the conventional time of arrival (TOA) and time difference of arrival (TDOA) systems, it does not require clock synchronization within the network, which enables a flexible and fast deployment. When deployed in the simplest form, it can effectively reduce system complexity and cost, whereas if all anchor nodes are equipped with full transmit and receive capability, the A-TDOA system can achieve superior performance using a novel receiver re-selection technique. Determining the physical position of a target node in a noisy environment is critical. In this thesis, two novel algorithms, namely, a two-step and a constrained least squares (CLS) algorithms, are proposed offering excellent accuracy and the best trade-off between complexity and precision respectively. The two-step algorithm exploits the advantages of the semi-definite programming (SDP) and the Taylor method, i.e., global convergence and high precision, to achieve superior performance. The CLS algorithm significantly reduces the computation complexity while achieving good accuracy. Despite extensive research efforts on ranging and localization modeling and simulation, knowledge about practical implementations is limited. For the first time, a complete prototype based on A-TDOA technique is implemented in hardware. All sub-systems are developed from scratch and undergone significant modifications for improved reliability. The design objective is low cost and low complexity, and therefore a non-coherent receiver architecture was adopted. The target node design is based on receive and re-transmit technique and is prototyped in analog domain to avoid clock offset and skews. The implemented system has been extensively tested in an outdoor and indoor radio environments. The accuracy obtained are 20.7 cm and 15.2 cm respectively. Comparison with the literature published up to date proves the excellent quality of the design and implementation. To better understand the localization accuracy, the error sources due to thermal noise, hardware limitation, radio propagation channel and clock jitter are identified and investigated. Mitigation methods are proposed to reduce errors. / Graduate

This master thesis purposes is create localization system using software defined radio. The purpose of this thesis is to create new localization system, which will be independent of existing systems. To create a localization system, we will use ADALM-PLUTO device to send and receive radio signals. This work contains a decription of serval possibilities how to create the localization system and description of their comunication.

The primary purpose of this thesis work is to design and implement a system supporting the fire-fighter’straining evaluation. The solution presented in this report comprises a real-time locating system andInertial Measurement Unit that collect the training data and an application built with the Unity3D gameengine used for processing. Before the presented application can process any data, a training facility must be recreated, and atrainer or an expert must define training guidelines, such as zones that a trainee must visit, objectshe/she has to see, and the required execution time. After this preparation and completed trainingsession, collected data is processed and the visualization together with evaluation process begins. Theprogram visualizes trainee’s position and his/her field of view and evaluates his performance. For thelatter, it uses the Unity3D collision detection feature. After the evaluation, the trainer can see detailedresults with recorded time stamps, and using them, he/she can fast forward to specific, important points,reducing the time to analyze trainee’s performance throughout the whole training. Tests which the authors conducted confirm that the built system meets requirements and is useful forevaluation of the trainee’s performance.

RFID (Radio Frequency Identification) system is a wireless system without any kinds of mechanical or optical connection between identifying and detected objects. It consists of two basic devices: a reader and tag. Recently with the development of the technology, SAW-RFID (Surface Acoustic Wave Radio Frequency Identification) tags come into market with acceptable price, as well as its size tends to miniaturization. We propose to use 3D wireless indoor localization system to detect the position of the tags. The reader converts radio waves returned from the SAW-RFID tag into a form, which can be useful to process the information. The system consists of SAW-RFID tags placed on the object and several RF Readers in the room. The readers sequentially transmit the impulse signals which are then reflected from different tags and received by readers. Then a signal round-trip TOA (Time of Arrival) between tags and readers can be estimated. We define a 3D coordinate system of the readers and calculate the positions of the tags using suitable specific algorithm. Our system is design to monitor a human body position. The goal is to detect a tumble of solitary living people. A case when the tag positions are identified to be below a per-set threshold means that something happened, and maybe a man has fallen on the ground. This emergency situation can be detected by the monitoring system which then sends information to an alarm system which can call the health centre to take care of the patient. In this paper, a 5 m×5 m×3 m indoor localization system is implemented in Matlab. The simulation results show a correct identification of a fallen man and accuracy of the high measurement below 30 cm. / 0762770008