京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19023号 / 農博第2101号 / 新制||農||1030(附属図書館) / 学位論文||H27||N4905(農学部図書室) / 31974 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 飯田 訓久, 教授 近藤 直, 准教授 中嶋 洋 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19505号 / 理博第4165号 / 新制||理||1598(附属図書館) / 32541 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 津田 敏隆, 教授 石川 裕彦, 教授 余田 成男 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19510号 / 理博第4170号 / 新制||理||1599(附属図書館) / 32546 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 井口 正人, 教授 平原 和朗, 教授 大倉 敬宏 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

No description available.

GNSS positioning has become a key element in everyday life of millions of people, from the person using google maps to move around an unknown city to the mailman or the DRON pilot who require it to carry out their work. All of them benefit in some way from the GNSS constellations and the position algorithms.The European Union through their GNSS constellation, Galileo, has recently made available a new service called Galileo High Accuracy Service (HAS). With the aim of improving the positioning solutions already provided by the Open Service (OS) to a centimetric level with the target of professional and commercial users requiring this high accuracy. As a result, in this Master Thesis project the steps of the development and implementation of a Software-Defined Radio to collect the High Accuracy corrections transmitted through Galileo GNSS constellation are going to be shown. The SDR itself is going to be made available so that other persons from companies to academia can benefit from it and see how the corrections are extracted and either use the algorithm or implement its own to be able to use this High Accuracy Service.

No description available.

Time synchronization is critical for the operation of radio base stations (RBS) in telecommunication companies. Global navigation satellite system (GNSS) is an existing technology to provide precise timing information to distributed RBSs. GNSS timing receiver is used for providing higher timing accuracy than normal GNSS receiver in this synchronization domain.In this thesis, an experiment method for GNSS timing receiver performance in urban canyon has been designed and implemented to evaluate information and the quality of the one pulse per second (1PPS) signal generated by two different GNSS timing receivers. Multi-path signals and the gathered satellite geometry caused by poor sky visibility is identified as the main influential factors to the performance of the GNSS timing receivers. A mathematical model has been built for estimating the multi-path effect. GNSS planning tools are used to simulate the number of line-of-sight (LOS) satellites and Dilution of Precision (DOP) value.Sentinel is a 1PPS signal analyzing equipment from Calnex. Sentinel has an embedded rubidium clock, GNSS antenna, and receiver, and it can produce 1PPS signals to be used as a reference. In this report, we installed our GNSS antenna of Sentinel on the roof and test GNSS antenna in two specified positions representing urban canyon and rooftop. Recorded NMEA messages from GNSS receiver can help us to study the number of visible satellites, PDOP value and multi-path signals in realistic situations.The results show how the noise and time phase of 1PPS signals will be influenced in urban canyons. Since, the geometry of used satellites is similar to the rooftop situation, the multi-path effect of signals is identified as the main reason of this difference.This information is useful when telecommunication companies want to install their radio base station in urban canyons. It will help Ericsson to understand how their GNSS timing receiver is working and how the urban canyon will influence its performance. / Tidssynkronisering är kritisk för driften av radiobasstationer (RBS) i telekommunikationsföretag. Global Navigation Satellite System (GNSS) är en befintlig teknik för att ge exakt tidsinformation till distribuerade basstationer. GNSS-baserade tidsmottagare används för att ge högre timing-noggrannhet än vanlig GNSS mottagare i denna synkroniseringsdomän. I denna avhandling har en experimentmetod för GNSS-timingmottagarnas prestanda i urban canyon utformats och implementerats för att utvärdera den genererade informationen och kvaliteten på en puls per sekund-signal (1PPS). Flervägssignaler och den samlade satellitgeometrin som orsakas av dålig himmelsynlighet identifieras som de mest inflytelserika faktorerna för GNSS-tidsmottagarnas prestanda. En matematisk modell har donstruerats för att estimera multi-path-effekten. GNSS-planeringsverktyg används för att simulera antalet LOS-satelliter och DOP-värde (Dilution of Precision). Sentinel är en 1PPS signalanalysutrustning från Calnex. Sentinel har en inbyggd rubidiumklocka, GNSS-antenn och mottagare, och den kan producera 1PPS-signaler som ska användas som referens. I den här rapporten installerade vi vår GNSS-antenn på Sentinel på taket och GNSS-testantennen i två angivna positioner som representerar urban canyon och tak. Inspelade NMEA-meddelanden från GNSS-mottagare kan hjälpa oss att studera antalet synliga satelliter, PDOP-värde och flervägssignaler i realistiska scenarier. Resultatet visar att ljud- och tidsfasen för 1PPS-signaler påverkas i urban canyons. Eftersom satellitgeometrin liknar den för antenner placerade på taket, så är identifieras flervägsutbredningen som huvudorsak för denna skillnad. Denna information är användbar när telekommunikationsföretag vill installera sina radiobasstationer i urban canyons. Det kommer att hjälpa Ericsson att förstå hur deras GNSS-timingmottagare arbetar och hur urban canyon påverkar dess prestanda.

: Previous research has explored associations between accelerometry and Global Navigation Satellite System (GNSS) derived loads. However, to our knowledge, no study has investigated the relationship between these measures and a known distance. Thus, the current study aimed to assess and compare the ability of four accelerometry based metrics and GNSS to predict known distance completed using different movement constraints. A correlational design study was used to evaluate the association between the dependent and independent variables. A total of 30 physically active college students participated. Participants were asked to walk two different known distances (DIST) around a 2 m diameter circle (small circle) and a different distance around an 8 m diameter circle (large circle). Each distance completed around the small circle by one participant was completed around the large circle by a different participant. The same 30 distances were completed around each circle and ranged from 12.57 to 376.99 m. Acceleration data was collected via a tri-axial accelerometer sampling at 100 Hz. Accelerometry derived measures included the sum of the absolute values of acceleration (SUM), the square root of the sum of squared accelerations (MAG), Player Load (PL), and Impulse Load (IL). Distance (GNSSD) was measured from positional data collected using a triple GNSS unit sampling at 10 Hz. Separate simple linear regression models were created to assess the ability of each independent variable to predict DIST. The results indicate that all regression models performed well (R = 0.960-0.999, R = 0.922-0.999; RMSE = 0.047-0.242, < 0.001), while GNSSD (small circle, R = 0.999, R = 0.997, RMSE = 0.047 < 0.001; large circle, R = 0.999, R = 0.999, RMSE = 0.027, < 0.001) and the accelerometry derived metric MAG (small circle, R = 0.992, R = 0.983, RMSE = 0.112, < 0.001; large circle, R = 0.997, R = 0.995, RMSE = 0.064, < 0.001) performed best among all models. This research illustrates that both GNSS and accelerometry may be used to indicate total distance completed while walking.

Geodetiska mätinstrument utvecklas konstant. Denna utveckling möjliggör attmätning med Global Navigation Satellite System (GNSS)-instrument nu kangenomföras utan att behöva horisontera stången som instrumentet ärmonterad på, detta eftersom själva mottagaren har en inbyggdlutningskompensator som konstant beräknar positionen för stångspetsen. Enav mottagarna som har en sådan inbyggd lutningskompensator är TrimbleR12i som lanserades 2020. Förutom att instrumentet kan mäta utan att varahorisonterat har mottagaren också andra funktioner som bidrar till förbättradpositionsbestämning, som en ny signalbearbetningsfunktion som gör att denpresterar bättre i svåra mätmiljöer, till exempel vid höga byggnader, underträd och så vidare. I den här undersökningen ligger fokus på hurlägesosäkerheten varierar mellan lutningsgraderna 0º, 10º, 20º, 30º, 40º och50º samt på hur tekniken presterar i svårare mätmiljöer med begränsad sikt.För att testa om tekniken klarar inmätning av dolda punkter i en svår miljö,genomfördes inmätning av fyra hushörn för en ca 17 m hög byggnad, somsenare jämfördes med inmätning av två hushörn för en lägre byggnad, cirka 10m hög. Något som också undersöktes var hur lägesosäkerheten påverkas avolika observationstider. De erhållna GNSS-resultaten jämfördes senare medreferenskoordinater. Dessa mättes in med totalstation från en station sometablerats med en GNSS-baserad stationsetablerings metod, nämligenrealtidsuppdaterad fri stationsetablering (RUFRIS) med 15 bakåtobjekt.Resultatet av mätningarna i olika lutningsgrad bekräftar det som var förväntat,nämligen att standardosäkerheten i både plan och höjd ökar i samband medökad lutningsgrad. De högsta standardosäkerheterna erhålls vid 40º och 50ºlutning. Resultatet bekräftar också att instrumentet klarar att prestera braäven i svår mätmiljö. Standardosäkerheten i plan på punkt C som ligger i ensvår mätmiljö hamnade mellan 1,8 cm till 7,6 cm vid 0º till 30º lutning och5 till 10 cm vid lutningarna 40º och 50º. De vertikala standardosäkerheterna ärmycket låga. I punkt A som befinner sig i en vanlig mätmiljö liggerstandardosäkerheten i höjd mellan 4 till 9 mm vid 0º till 30º lutning och 0,7cm till 1,7 cm vid lutningarna 40º och 50º. I den svåra mätmiljön ligger devertikala standardosäkerheterna mellan 2,1 cm till 6,9 cm vid 0º till 30ºlutning och 3,6 till 8,9 cm vid 40º och 50º lutning. De vertikala osäkerheternaökar också i samband med ökad lutningsgrad även om ökningen inte är likastor som för de horisontella osäkerheterna. Slutsatsen av undersökningen äratt instrumenten fungerar bra i svår mätmiljö med begränsad sikt medstandardosäkerhet på 1,8 till 7,6 cm i plan vid 0º till 30º lutning och 5,1 till 10cm vid 40º och 50º lutning. Det går också att genomföra mätningen med upptill 50º lutning, åtminstone i vanlig mätmiljö med standardosäkerhet mellan1,7 cm och 5,6 cm. I svår mätmiljö hamnar osäkerheterna på dm-nivå vidlutning ≥40º. / Geodetic measuring instruments are constantly developing. This developmenthas now made it possible to measure with Global Navigation Satellite System(GNSS) instruments without leveling the survey rod the instrument ismounted on. This is because the receiver itself has a built-in tilt compensatorthat constantly calculates the tip position of the survey rod. One of thereceivers with such a built-in tilt compensator is Trimble R12i, which waslaunched in 2020. In addition to the instrument being able to measure withoutbeing leveled, the receiver also has other functions that contribute toimproved position determination, such as a new signal processing functionthat performs better in challenging measurement environments, for exampleclose to tall buildings, under trees and so on. This study focuses on how theposition uncertainty varies between the tilt angles 0º, 10º, 20º, 30º, 40º and50º and how the receiver performs in challenging environments with limitedvisibility of the satellites due to different objects such as tall buildings andtrees. To test whether the technology can measure hidden points in achallenging environment, four house corners were measured for a tallerbuilding. This was later compared with two house corners measured beside alower building. It was also investigated how the position uncertainty isaffected by different observation times. The result obtained with the GNSSreceiver was later compared with reference coordinates that were measuredwith a total station that was established with real-time updated free stationestablishment (RUFRIS) relative to 15 network-RTK positions.The result of the measurements in different tilt angles confirms what wasexpected, namely that the standard uncertainty in both horizontal and verticalincreases with the tilt angle. The highest standard uncertainty was obtainedwith 40º and 50º tilt angles. The result also confirms that the instrumentperforms well even in a challenging measuring environment. The horizontalstandard uncertainty at point C (challenging measuring environment) isbetween 1.8 to 7.6 cm for 0º to 30º tilt angles and 5 to 10 cm at tilt angles 40ºand 50º. The vertical standard uncertainty for point A (normal measuringenvironment) is between 4 to 9 mm at tilt angles of 0º to 30º and 0.7 to 1.7cm at tilt angles of 40º and 50º. In difficult measurement environments, thevertical standard uncertainties are between 2.1 to 6.9 cm at 0º to 30º tilt and3.6 to 8.9 cm at 40º and 50º tilt angle. The conclusion of the study is that theinstrument works well in challenging measurement environments withstandard uncertainties between 1.8 to 7.6 cm in the horizontal at 0º to 30º tiltangles and 5.1 to 10 cm at 40º and 50º tilt angles. It is also possible to carryout measurements with a tilt angle up to 50º, at least in a normal environmentwith standard uncertainties between 1.7 cm and 5.6 cm. In challengingmeasurement environments, the uncertainties can be at dm-level at tilt angles≥ 40º.

This thesis presents methods for robust precision landing of unmanned air vehicles (UAVs) on platforms at sea. Localization methods are proposed for UAV-to-boat state estimation for systems that employ real- time kinematic (RTK) global navigation satellite system (GNSS) and vision sensors. Solutions for GNSS-only are first presented, followed by the fusion of GNSS and vision. The important problem of sensor intrinsic calibration is solved with a novel offline batch estimation approach. Hardware results are presented for all methods. Our calibration of GNSS-to-camera is shown to estimate sensor offsets with millimeter level accuracy. Localization systems are combined with custom state machines that manage the landing attempt via a novel descent cone. This conical threshold enforces a safe and accurate landing. Our landing methods are demonstrated in real-world experiments and achieve consistent accurate landings with error below 10 cm. The fusion of camera and RTK is shown to produce a robust landing system with redundant localization sources.