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Recently, utilization of position information by global navigation satellite system (GNSS) is expected in various fields. However, it's difficult to show unambiguously accuracy since positioning accuracy varies by measurement environment. We bring sky view factor (SVF) to evaluation of positioning accuracy, and evaluate it positioning accuracy of long time data in the places where SVF are high or...
This paper proposes a new filter design optimized for GNSS attitude determination applications using low cost devices. The filter contains all relevant constraints and observations, including double differenced carrier phase and code observations along with MEMS-IMU observations. Benefited from the unified treatment, the priori information is well used during the resolution of double differenced GNSS...
When a vehicle passes through a blind area such as a high-rise building, a tunnel or an overpass, it is prone to satellite signals being poor or interrupted, and DR (Dead Reckoning) has autonomous navigation capability and is not influenced by the environment. However, DR navigation accuracy is rather low, due to the error will increase with time. Therefore, the GNSS(Global Navigation Satellite System)...
Intelligent Transportation System (ITS) applications for integral and cooperative vehicle safety as well as some Advanced Driver Assistance Systems (ADASs) benefit from precise determination of relative positions between dynamic traffic objects. With conventional Global Navigation Satellite System (GNSS) measurements, e.g. using Global Positioning System (GPS), the required accuracy cannot be achieved...
Recently, low-cost dual constellation receivers with simultaneous tracking of GPS and GLONASS satellites and raw carrier phase output have become available. This enables a faster and more reliable ambiguity fixing especially in areas with limited satellite visibility, e.g. street canyons. In this paper, we present a combined GPS/GLONASS RTK positioning with code multipath estimation for low-cost receivers...
GNSS chipsets found in mobile phones are a technological wonder. Not only do they occupy a few mm2, draw a handful of milliamps from the battery and possible share the die with another systems such as WLAN, Bluetooth or NFC, but also they implement very advanced processing techniques to be able to operate with meter-level accuracy in very adverse conditions caused by interferences from other components...
Rotten bridges and highways, the raised population density and car penetration as well as daily and long-time roadworks are just a few reasons of the modern transportation challenge: the steadily increase of traffic density. This unavoidable trend also comes along with the well-known negative effects such as traffic jams, car accidents and CO2 emissions. Hence, current research approaches aim on generally...
The Global Positioning System can be used to determine the attitude of a vehicle by using multiple receivers in fixed positions. The carrier phase measurements, which have millimetric precision, can be used for this purpose. However, these measurements have an unknown number of integer cycles named phase ambiguities, which have to be determined. Of all the methods known, LAMBDA is currently acknowledged...
Low quality measurements cause performance degradation in global navigation satellite system (GNSS) high precision positioning techniques. Based on a real-time kinematic (RTK) technique that integrates measurements from different navigation constellations and signal frequencies, an algorithm that identifies and discards low quality measurements to ensure high carrier cycle integer ambiguity fix rate...
Precise Point Positioning with low-cost GNSS receivers is attractive for numerous applications, as it can provide centimeter-level positioning without the exchange of raw measurements from a reference station. However, pseudorange multipath has to be accurately considered for a reliable ambiguity fixing. In this paper, we derive a precise model for the pseudorange multipath from the received signal,...
For heterogeneous wireless network, the use of positioning information with global navigation satellite system (GNSS) such as global positioning system (GPS), quasi zenith satellites system (QZSS) in Japan and the global navigation satellite system in Russia (GLONASS) has been very effective. In this paper, the quantitative relation of positioning accuracy on various GNSS and sky view factor are described...
The positioning accuracy of the traditional GPS single point positioning is lower and applies only to the occasion of the low accuracy of the positioning. With the development of GPS positioning technology, the requirements for the positioning accuracy are also constantly improving, using differential GPS technology can improve the positioning accuracy significantly. We can learn from differential...
This paper provides a closed form analytical solution for TDOA three dimensional (3D) acoustic source localization with four synchronized ultrasonic generators or receivers. Then a pure analytical solution for Geometric Dilution of Precision (GDOP) with four signal generators or receivers is derived instead of a least square solution. The proposed GDOP model removes the effect of time clock drift,...
Cooperative maneuvers between trains like platooning or dynamic merging and splitting of train sets have the potential to increase efficiency and flexibility in railway operations. However, such maneuvers are safety critical and require continuously accurate relative position and velocity information. This information cannot be provided by infrastructure based train control systems like the European...
This paper introduces the proof of concept of low-Earth-orbit satellite attitude determination using GNSS, mainly GPS satellite signals. Two methods are considered and compared in detail: carrier phase measurements and signal-to-noise ratio (SNR-RSS) method. A preliminary design to be used in testing the algorithms is explained, and results of simulations with RSS method are presented.
Faults in the GNSS measurements are the main reason for uncertainty positioning. Accuracy can thus be maximized by selecting only those observations least contaminated by faults to form the navigation solution (positioning) and discarding the rest. In this paper, we propose an algorithm to solve the problem of multi faults in the GNSS observations (pseudorange). The algorithm is based on observations...
The problem of relative positioning is introduced and some solutions are proposed. The topic is studied as applied to the Global Positioning System (GPS). Unlike usual GPS positioning, in relative positioning, the navigator's location in some Earth-bound coordinates is not the desired result, but instead, the position of one GPS user relative to another. The relative position is given in user-centered...
Global Positioning System (GPS) is the emerging technology extending its applications in the field of surveying, navigation, military etc., and these applications demands multiple levels of accuracy ranging from tens of meters to sub-millimetre level. Hence there is a need to develop systems, methods and a technique to meet the demand of high accuracy.GPS provides its services in two different standards,...
Cooperative approaches are becoming of great interest in automotive research. One of the most important ITS applications is cooperative localization. In this paper, the concept of a dynamic base station DGPS (DDGPS) and its application in the vehicular cooperative localization is introduced and discussed. The DDGPS is a decentralized cooperative method which aims to improve the GPS positioning by...
In this paper a novel Vehicular cooperative map matching method is presented. This map matching method uses the V2V communication in a VANET to exchange GPS information between vehicles. Then vehicles can apply the road constraints of other vehicles in their own map matching process and acquire a significant improvement in their positioning. The dependency of GPS measurements between different vehicles,...
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