Studying the positioning accuracy for dynamic (moving) objects with the use of multifrequency oblique-incidence sounding of ionospheric radio channels by chirp signals

The article presents results of verification of the kinematic measurements usefulness for precise real-time positioning RTK in the local reference system. These measurements allow for continuous RTK measurements in the event of temporary interruptions in radio or internet connections, which are the main reason for interruptions in RTK kinematic measurements and cause a decrease in the reliability and efficiency of this positioning method. Short interruptions communication are allowed during the loss of the key correction stream from the local RTK support network, so the global corrections obtained from the geostationary satellite are used. The aim of the article was to analyze the accuracy of measuring the position of moving objects. Practical conclusions were formulated according to the research subject, the presented mathematical models, the experiment and the analysis of the obtained results.

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Design of the UWB Positioning System Simulator for LOS/NLOS Environments

Sensors ◽

10.3390/s21144757 ◽

2021 ◽

Vol 21 (14) ◽

pp. 4757

Author(s):

Krzysztof Paszek ◽

Damian Grzechca ◽

Andreas Becker

Keyword(s):

Energy Demand ◽

Moving Objects ◽

Smart Cities ◽

Field Tests ◽

Ground Truth ◽

Line Of Sight ◽

Test Scenario ◽

Positioning Accuracy ◽

The Real ◽

The Impact

UWB is a rapidly developing technology characterised by high positioning accuracy, additional data transferability, and communication security. Low costs and energy demand makes it a system that meets the requirements of smart cities (e.g., smart mobility). The analysis of the positioning accuracy of moving objects requires a ground truth. For the UWB system, it should have an accuracy of the order of millimetres. The generated data can be used to minimize the cost and time needed to perform field tests. However, there is no UWB simulators which can consider the variable characteristics of operation along with distance to reflect the operation of real systems. This article presents a 2D UWB simulator for outdoor open-air areas with obstacles and a method of analysing data from the real UWB system under line-of-sight (LOS) and non-line-of-sight conditions. Data are recorded at predefined outdoor reference distances, and by fitting normal distributions to this data and modelling the impact of position changes the real UWB system can be simulated and it makes it possible to create virtual measurements for other locations. Furthermore, the presented method of describing the path using time-dependent equations and obstacles using a set of inequalities allows for reconstructing the real test scenario with moving tags with high accuracy.

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Pedestrian Dead Reckoning-Assisted Visual Inertial Odometry Integrity Monitoring

Sensors ◽

10.3390/s19245577 ◽

2019 ◽

Vol 19 (24) ◽

pp. 5577 ◽

Cited By ~ 1

Author(s):

Yuqin Wang ◽

Ao Peng ◽

Zhichao Lin ◽

Lingxiang Zheng ◽

Huiru Zheng

Keyword(s):

Moving Objects ◽

Dead Reckoning ◽

Indoor Positioning ◽

Visual Observation ◽

Measurement Unit ◽

Observation Error ◽

Positioning Accuracy ◽

Integrity Monitoring ◽

Background Texture ◽

Pedestrian Dead Reckoning

Visual inertial odometers (VIOs) have received increasing attention in the area of indoor positioning due to the universality and convenience of the camera. However, the visual observation of VIO is more susceptible to the environment, and the error of observation affects the final positioning accuracy. To address this issue, we analyzed the causes of visual observation error that occur under different scenarios and their impact on positioning accuracy. We propose a new method of using the short-time reliability of pedestrian dead reckoning (PDR) to aid in visual integrity monitoring and to reduce positioning error. The proposed method selects optimized positioning by automatically switching between outputs from VIO and PDR. Experiments were carried out to test and evaluate the proposed PDR-assisted visual integrity monitoring. The sensor suite of experiments consisted of a stereo camera and an inertial measurement unit (IMU). Results were analyzed in detailed and indicated that the proposed system performs better for indoor positioning within an environment that contains low illumination, little background texture information, or few moving objects.

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Investigation of localization accuracy in UWB relative ranging system

Journal of Physics Conference Series ◽

10.1088/1742-6596/2094/4/042041 ◽

2021 ◽

Vol 2094 (4) ◽

pp. 042041

Author(s):

Timur V Krasnov

Keyword(s):

Moving Objects ◽

Operating Conditions ◽

Reference Points ◽

Harsh Environment ◽

Positioning System ◽

Relative Positioning ◽

Positioning Accuracy ◽

Localization Accuracy ◽

Hybrid Combination ◽

Fixed Reference

Abstract The hybrid combination of a traditional positioning system with fixed reference points and a relative positioning system based on the relative position of network subscribers on the basis of measuring the distances between them increases the availability of the positioning system for moving objects in harsh environment and the accuracy of their positioning. Depending on the operating conditions, the cascade measurement of the distances between the nodes expands the working area with an acceptable positioning accuracy with the same number of fixed anchors.

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