Statistical Sensor Fusion of Ultra Wide Band Ranging and Real Time Kinematic Satellite Navigation

Position, velocity and time (PVT) can be calculated from Global Positioning System (GPS). Two types of GPS measurement models are present, code phase measurement model and carrier phase measurement model. Range measurement in GPS is affected by different types of errors including atmospheric, multipath, satellite and receiver clock and ephemeris errors. Atmospheric errors are the biggest source of error amongst these. Receivers within close proximity to each other face mostly same atmospheric errors from GPS signal. Several differential techniques have been developed during the last few years to mitigate these common errors. It means that the accuracy can be improved by using multiple receivers which mitigate the majority of errors. Real Time Kinematic (RTK) concept uses carrier phase measurements, which have high accuracy. RTK concept was originally developed for application such as surveying. The unknown ambiguity in the number of cycle between each satellite and receiver node is the main issue in RTK technique, moreover these ambiguities are integer numbers. Once the ambiguity is solved, it remains constant as long as the receiver maintains a phase lock on satellites signals. However, the loss of phase lock results in cycle slips and the ambiguity needs to solve again. In this work, RTKLIB, an open source software, is used for the RTK GPS positioning. Ultra-Wide Band (UWB) is known since early 1900s with synonymous terms such as impulse, time domain, nonsinusoidal, baseband, carrier free, orthogonal function and large relative bandwidth radio signals. The huge frequency bandwidth of UWB makes it suitable for positioning and navigation applications. Multipath resistance, high accuracy, low cost and low power implementation are other features of UWB. The huge bandwidth in frequency domain corresponds to short pulse in time domain, usually of nanosecond (ns) order. The Time of arrival (TOA), the time difference of arrival (TDOA) and the received signal strength (RSS) are known methods to calculate the range between the source and the target through UWB. TOA and TDOA are highly accurate but have clock synchronization problem. To overcome this problem, a modified method known as two-way time-of-flight can be used. BeSpoon phone equipped with UWB is used here for UWB ranging. To summarize the previous discussion, RTK GPS positioning has a high accuracy but has integer ambiguity resolution problem which causes cycle slips and requires good satellite visibility as well. Moreover RTK GPS positioning solution is for outdoor applications only and has high dynamic outdoor range. UWB, on the other hand, can give highly accurate positioning solution but has low dynamic range. UWB can be used for both indoor and outdoor applications. Moreover, high bandwidth of UWB makes it multipath resistant and as result can be used in shadow areas. Thus, the fusion of RTK GPS and UWB positioning may compensates the limitations of both and result in better performance system. In this thesis a Kalman filter is used for fusion of UWB and RTK GPS positioning solutions. UWB gives range from tags which are in meter and relative to BeSpoon phone while RTK GPS positioning solution is in geodetic coordinates form (latitude and longitude). Three steps are involved in fusion; first, convert UWB ranges to position in local coordinate by using trilateration, second, convert geodetic coordinates of RTK GPS to local coordinates through rotation matrix and third, use Kalman filter for fusion of both positioning data. The main goal of the thesis is the fusion of both RTK GPS and UWB positioning solutions with the help of Kalman filter in order to obtain better performance compare to stand-alone RTK GPS. Tampere University of Technology (TUT) parking area is used for testing. One corner of TUT parking area has the known coordinate point which is used for the base station of RTK GPS. Reference track and tags positions are drawn through Laser instrument Leica TPS1200 which has millimeter level of accuracy. Measurement results show that the fusion of UWB and RTK GPS positioning solutions have better performance compared to stand-alone RTK GPS solution. Whenever measurement from RTK GPS gives erroneous/missing result, the measurement from UWB sensor corrects it and the resulting solution from filter has better performance

New Approach of Indoor and Outdoor Localization Systems

Accurate determination of the mobile position constitutes the basis of many new applications. This book provides a detailed account of wireless systems for positioning, signal processing, radio localization techniques (Time Difference Of Arrival), performances evaluation, and localization applications. The first section is dedicated to Satellite systems for positioning like GPS, GNSS. The second section addresses the localization applications using the wireless sensor networks. Some techniques are introduced for localization systems, especially for indoor positioning, such as Ultra Wide Band (UWB), WIFI. The last section is dedicated to Coupled GPS and other sensors. Some results of simulations, implementation and tests are given to help readers grasp the presented techniques. This is an ideal book for students, PhD students, academics and engineers in the field of Communication, localization & Signal Processing, especially in indoor and outdoor localization domains

Positioning and Sensing System Based on Impulse Radio Ultra-Wideband Technology

Impulse Radio Ultra-Wideband (IR-UWB) is a wireless carrier communication technology using nanosecond non-sinusoidal narrow pulses to transmit data. Therefore, the IR-UWB signal has a high resolution in the time domain and is suitable for high-precision positioning or sensing systems in IIoT scenarios. This thesis designs and implements a high-precision positioning system and a contactless sensing system based on the high temporal resolution characteristics of IR-UWB technology. The feasibility of the two applications in the IIoT is evaluated, which provides a reference for human-machine-thing positioning and human-machine interaction sensing technology in large smart factories. By analyzing the commonly used positioning algorithms in IR-UWB systems, this thesis designs an IRUWB relative positioning system based on the time of flight algorithm. The system uses the IR-UWB transceiver modules to obtain the distance data and calculates the relative position between the two individuals through the proposed relative positioning algorithm. An improved algorithm is proposed to simplify the system hardware, reducing the three serial port modules used in the positioning system to one. Based on the time of flight algorithm, this thesis also implements a contactless gesture sensing system with IR-UWB. The IR-UWB signal is sparsified by downsampling, and then the feature information of the signal is obtained by level-crossing sampling. Finally, a spiking neural network is used as the recognition algorithm to classify hand gestures

Hybrid module for industrial localization

Tato diplomová práce si klade za cíl návrh hybridního lokalizačního zařízení, které je schopno lokalizace uvnitř i vně budov. Lokalizace uvnitř budov je dosažena pomocí technologie Ultra Wideband a venkovní lokalizace je provedena pomocí kombinace technologie RTK GNSS a PPP pomocí open - source softwaru zvaného RTKLIB. První část textu se zaměřuje na vysvětlení používaných technologií a výběr nejpřesnější technologie pro venkovní lokalizaci. Druhá část se zaměřuje ma vývoj potřebného hardware a software finálního zařízení a na integraci systému pro venkovní lokalizaci do systému pro lokalizaci vnitřní. Výstupem práce je plně funkční zařízení, které je schopné plynulé lokalizace uvnitř i vně budov. Funčnost celého zařízení je dokázána na finálních testech uskutečněných ve vnitřních i venkovních prostorách. Na závěr také práce zmiňuje možná vylepšení celého zařízení, která mohou být v budoucnu provedena.This thesis focuses on the design of a hybrid localization device capable of locating both outdoors and indoors. Indoor positioning is achieved by Ultra Wideband and outdoor localization utilizes the RTK GNSS positioning solution together with PPP provided by an open - source software called RTKLIB. The first part of the the text is aimed at explaining the underlying technologies and choosing the most precise technology for outdoor localization purposes. The second part focuses on the hardware and software design of the final device and on the integration of the outdoor positioning solution to the indoor localization system. The output of this thesis is a a working device, capable of seamless outdoor and indoor localization. The functionality of the device is shown in final tests both indoors and outdoors. In conclusion, the thesis also mentions possible improvements in the future.

Tracking and positioning using phase information from estimated multi-path components

High resolution radio based positioning and tracking is a key enabler for new or improved cellular services. In this work, we are aiming to track user movements with accuracy down to centimeters using standard cellular bandwidths of 20-40 MHz. The goal is achieved by using phase information from the multi-path components (MPCs) of the radio channels. First, an extended Kalman filter (EKF) is used to estimate and track the phase information of the MPCs. Each of the tracked MPCs can be seen as originating from a virtual transmitter at an unknown position. By using a time difference of arrival (TDOA) positioning algorithm based on a structure-of-motion approach and translating the tracked phase information into propagation distances, the user movements can be estimated with a standard deviation of the error of 4.0 cm. The paper should be viewed as a proof-of-principle and it is shown by measurements that phase based positioning can be a promising solution for movement tracking in cellular systems with extraordinary accuracy

Recent Advances in Indoor Localization Systems and Technologies

Despite the enormous technical progress seen in the past few years, the maturity of indoor localization technologies has not yet reached the level of GNSS solutions. The 23 selected papers in this book present the recent advances and new developments in indoor localization systems and technologies, propose novel or improved methods with increased performance, provide insight into various aspects of quality control, and also introduce some unorthodox positioning methods