Positioning System Satellites Research Articles

Study on the detection of power line operation anomalies in the Hexi Corridor based on multi-scale filtering of BeiDou satellite signals

In the artificial intelligence detection of power line anomalies, the identification effect is determined by the positioning process of two-dimensional map, which is also a difficult point in this field Therefore, this paper proposes a method to detect the abnormal operation of power lines in Hexi Corridor based on multi-scale filtering of Beidou satellite signals. Multi-scale processing is carried out by wavelet transform to obtain multiple wavelet basis functions of different scales. On this basis, a two-dimensional time–frequency diagram is drawn according to the results of continuous wavelet transform. The adaptive multi-time frequency entropy method is selected to divide the two-dimensional time–frequency map into multiple layers and scales, and the adaptive multi-scale time–frequency entropy of the time–frequency plane is calculated. After smoothing the obtained power line position signal by S-G filtering method, the power line position signal of Hexi Corridor is obtained by GPS/ Beidou dual-mode satellite positioning system, and the positioning signal is optimized by using the positioning mechanism of multiple receiving stations. Realize the abnormal operation detection of power lines in Hexi Corridor. The experimental results show that this method can obtain more accurate positioning signals, and the geometric accuracy factor GDOP fluctuates in the range of 0 ∼ 2. The unsmooth signal can be effectively removed; The maximum error result of abnormal position detection is 1.22kn；; At the same time, the abnormal displacement section of the line can be determined.

The study of total electron content on ionosphere by using single frequency GPS receiver

In this research, we studied total electron content (TEC) on ionosphere by using single frequency from global positioning satellite system (GPS) satellite receiver. According to the ionospheric disturbance, ionospheric delay time on TEC is one of the most significant errors in GPS navigation systems. The positioning errors for GPS satellite systems from ionospheric delay depends on TEC over the region of interest as low latitude, Thailand. In research methodology, we proposed our ionospheric delay dataset on the period of the year 2004–2023 into the single frequency TEC method for finding GPS TEC. We investigated single frequency GPS TEC in three different stations, Bangkok, Chiang Mai, and Chumphon. Each station was installed the single and dual frequency GPS receivers for receiving the GPS signals over Thailand region. We investigated and compared single frequency GPS TEC results with dual frequency GPS TEC, International GNSS Service TEC (IGS TEC), and International Reference Ionosphere TEC (IRI TEC) in the year 2023. As the results, TEC using the single frequency GPS receiver is significantly statistical to be use for the study TEC on ionosphere over low latitude, Thailand.

Analysis of the possibility of using the satellite navigation system in the railway traffic control systems

The analysis of the possibility of using satellite navigation for rail vehicle positioning, which is the subject of many studies and projects, is aimed at assessing the uncertainty and accuracy of train positioning using satellite navigation systems, along with defining its impact on the capacity and safety of the rail infrastructure. Existing studies in this area prevent a clear assessment of the feasibility of implementing a satellite navigation system for rail vehicle positioning in rail traffic control systems. Therefore, it is necessary to analyze the possibility of using satellite navigation for rail vehicle positioning in terms of research problems arising from the limitations of satellite positioning system functionality, which include parameters related to accuracy, reliability, and speed of information transfer between the vehicle and the rail traffic control system. The implementation of the research work should be focused on developing a research model, subject to validation for the parameters and conditions of movement of rail vehicles in the defined area of railroad infrastructure, adopted within the framework of the work carried out. The research and the model form the basis for developing the knowledge of implementing satellite navigation in practical solutions on the railroad network.

Identification Method of High Incidence Areas of Bad Driving Behaviors Based on DBSCAN-Graham Combination

<p>This study utilizes data obtained from vehicle positioning, speed, and engine status through satellite positioning system monitoring terminals. The data is processed using spherical interpolation of latitude and longitude to handle missing values. The study establishes indicators for identifying bad driving behaviors, including speeding, rapid acceleration and deceleration, prolonged vehicle idling, and fatigue driving. The traditional DBSCAN algorithm is improved by incorporating both temporal and spatial search ranges into the algorithm, enabling cluster analysis of bad driving behaviors from both temporal and geographical perspectives. Finally, the Graham algorithm is utilized to calculate cluster boundaries, determining the specific locations and boundaries of high incidence areas of bad driving behaviors. This research aids regulatory authorities in more precisely supervising risk areas during transportation processes in terms of time and location.</p> <p> </p>

Quantitative identification of causes of instrumental acoustic signal distortion in Global Navigation Satellite System-Acoustics Combination observations.

The Seafloor Geodetic Observation-Array (SGO-A), operated by the Japan Coast Guard, relies on the Global Navigation Satellite System-Acoustics combination (GNSS-A) technique, which integrates satellite positioning systems and undersea acoustic ranging to determine seafloor crustal deformation at the centimeter level for earthquake disaster prevention. Recently, we found distortion in the SGO-A 10-kHz carrier wave that degraded the accuracy. Carrier wave distortion can cause errors on the scale of several centimeters to twenty centimeters, which greatly impedes centimeter-level observations. This study investigated this carrier wave degradation by an underwater acoustic communication experiment conducted in 2022, using a transducer similar to that used by SGO-A. Also, we reproduced degraded waveforms through a grid search-like method for quantitatively evaluating the extent to which the interior of the equipment contributed to deterioration. Our results underscore the importance of careful consideration in signal processing, as the observed waveform degradation is not solely attributed to hardware structures but also to internal electrical circuits. The findings suggest that conventional signal identification methods may lead to errors, providing motivation for a shift towards experimental and experiential timing-based waveform identification approaches to enhance accuracy in GNSS-A systems.

Design and Experiment of an Agricultural Field Management Robot and Its Navigation Control System

The application of robotics has great implications for future food security, sustainable agricultural development, improving resource efficiency, reducing chemical pesticide use, reducing manual labor, and maximizing field output. Aiming at the problems of high labor intensity and labor shortage in the fields of pesticide application, weeding, and field information collection, a multifunctional and electric field management robot platform is designed, which has four switching steering modes (Ackermann steering, four-wheel steering, crab steering, and zero-radius steering), and its wheel-track can be automatically adjusted. Commonly used spraying booms, weeders, crop information collectors, and other devices can be easily installed on the robot platform. A multi-sensor integrated navigation system including a satellite positioning system, an RGB camera, and a multi-line lidar is designed to realize the unmanned driving of the robot platform in a complex field environment. Field tests have shown that the robot can follow the set route, and tests under simulated conditions have indicated that it can also dynamically correct paths based on crop rows by using a visual system. Results from multiple trials showed that the trajectory tracking accuracy meets the requirements of various field management operations.

Application of particle filter algorithm in satellite positioning and navigation system

To understand the application of satellite positioning and navigation system, the application of a particle filter algorithm in satellite positioning and navigation system is studied. In this paper, firstly, the state equation of the system is established according to the correlation between the parameters of GPS output, and the particle filter algorithm is applied to filter the GPS-received data. In the CPS navigation system, DSP is used to decode and filter the output signal of the CPS receiver. The results show that when the GPS signal is disturbed, the particle filter algorithm can deal with the abnormal observation samples well, which shows that it can reduce the computational complexity and improve the GPS positioning accuracy, and have a certain robustness.

COMPLEX METHOD OF DETERMINING THE LOCATION OF SOCIAL NETWORK AGENTS IN THE INTERESTS OF INFORMATION OPERATIONS

The researcher developed a method for determining the location of social network agents in the interest of conducting an information operation based on a comprehensive approach to data analysis of the information system. The relevance of the method is determined by the need to specify the enemy's target audience in the area of the information operation. Results. The author proposed a complex method for determining the location of social network agents, which is based on the combination of data from the analysis of the social connections of the specified agent, geotags and the time of registration of his friends in the social network, databases of IP addresses and geolocations of social network agents. The advantage of the developed method is the possibility of its application without direct access to the devices of agents of the social network that use the data of global positioning satellite systems. Conclusion. The application of the proposed complex method of determining the location of agents of social networks makes it possible to increase the effectiveness of information operations due to a more accurate definition of the enemy's target audience in the area of operations. The direction of improvement of the developed method can be its integration with complex information systems of psychological influence, as well as the use of machine learning methods and algorithms.

Remote Sensing and Geographic Information Systems for Precision Agriculture: A Review

Precision agriculture aims to optimize crop production and minimise environmental impacts by using information technology, remote sensing, satellite positioning systems, and proximal data gathering. This review paper examines current applications and future directions of remote sensing and geographic information systems (GIS) for precision agriculture. Remote sensing provides data on crop health, soil conditions, water status, and yield which can guide variable rate applications within fields. Satellite and aerial platforms allow multispectral and hyperspectral imaging for vegetation indices analysis, crop classification, and stress detection. GIS technology integrates these data layers to model and map variations, develop prescription maps, and analyse spatial relationships. Key research frontiers include high-resolution satellite and drone data for within-field analysis, better integration of proximal and remote sensing, online nutrient and yield monitors, real-time prescription modelling, and predictive analytics using machine learning. Adoption continues to increase with better data analytics tools and greater economic returns realized. Remote sensing and GIS provide an integral platform for variable rate technologies, predictive modelling, and data-driven decision-making for precision agriculture.

Underwater autonomous orientation using submarine light intensity gradient

It is a huge challenge for autonomous underwater vehicles (AUVs) to determine heading autonomously without the signal of satellite or underwater acoustic positioning system. The underwater polarization navigation is a newly-developed solution for self-orientation. However, the polarization navigation depending on the Rayleigh scattering model is susceptible to the multiple scattering induced by water depth. To address this issue, the underwater light intensity field is exploited benefiting from its environment suitability. By means of calculating the gradient of light intensity, a vector-field model, with resemblance to the ideal Rayleigh model in geometry, can be established for solar-tracking. The integrated navigation model is built based on the solar vector estimated by light intensity gradient (LIG) and inertial navigation system for heading determination. The static test in water tank and dynamic sea trial were conducted to validate the effectiveness of the LIG-based solar-tracking and orientation method, respectively.

Exploring the behavior feature of complex trajectories of ships with Fourier transform processing: a case from fishing vessels

The significant uncertainty and complexity of vessels at sea poses challenges for regulatory bodies in the fishing industry. This paper presents a method for identifying fishing vessel trajectory characteristics involving the Fourier series transform. The model utilizes the Fourier series and Gaussian mixture clustering to address the complexity and uncertainty issues in fishing vessel trajectories. First, the vessel trajectories undergo a process of dimensionality expansion and projection along the temporal axis. The relationship between trajectories and complex plane projection was elucidated in this process. Second, a vessel trajectory identification model involving Fourier transformation was constructed. Subsequently, the phase spectrum was assigned binary values using differentiation, and the phase spectrum characteristics of the transformed trajectories through Fourier transformation were analyzed. Finally, six encoding formats for fishing vessel motion trajectories in phase spectrum encoding are introduced, along with the determination of uncertain vessel motion range through mixed Gaussian clustering. This method has been validated using a dataset comprising 7,000 fishing vessel trajectories collected from the Beidou satellite positioning system. The results demonstrate that the range of uncertain vessel motion was able to be obtained with the assistance of Gaussian mixture clustering, with an 80% probability position of approximately 1,000 m and a 50% probability position of around 2,000 m. Effective identification of fishing vessel operating and navigational states was achieved, leading to the determination of a safety distance for fishing vessels in the range of 1,000m–2,000 m. This research holds important reference value for fishery regulatory agencies in terms of supervising fishing vessels and maintaining a safe navigational distance.

Train Speed and Distance Calculation Methods Using Measuring Device Independent of Vehicle Monitoring Device

The method for detecting the train speed and position without using wayside equipment, such as track circuit, contribute to developing technologies for energy-saving operations and simplifying protection equipment. In this paper, the analysis methods of measured data from accelerometers are studied to determine the train speed and position simply and accurately and to make speed profiles. To effectively use the data measured by the accelerometer, discrete Fourier transform is applied to remove the noise from the measurements. Two accelerometers were used to increase accuracy, and differences of sensing and the state of motion of the train were considered to remove noise effectively. Experimental results show that the speed and distance of train are clearly different from the actual values when the calculation is directly based on measured data. Therefore, the speed and distance of train could be obtained adequately and speed profiles are also generated when the proposed method is applied. Finally, the proposed methods were confirmed by using a satellite positioning system and speedometer records.

Accounting of agricultural using individual electronic cadastral maps

Introduction. Digitization of land relations led to the development and implementation of state electronic geocadastral maps. However, the development of GIS technologies enabled the economic use of electronic cadastral maps by agricultural enterprises for the purposes of optimizing agricultural management. Effective management is based on accounting information, so an accounting of agricultural activities in the conditions of using individual cadastral maps needs to improve first of all.Purpose. The purpose of the article is to improve the accounting of agricultural activities for the informational support of agricultural management, which involves the management of land resources of agricultural enterprises, in the conditions of the use of individual electronic cadastral maps.Methods. In the process of scientific research, a systematic methodical approach in combination with innovative, functional methods and methodical tools of generalization, bibliographic and comparative analysis was used to realize the purpose of article.Results. The expediency of personalizing the use of information from the State Geocadastre for the formation of individual electronic cadastral maps, which is valuable for accounting and management of agricultural activities, is substantiated. The procedure for the division and consolidation of land plots within the spatial and territorial boundaries regulated by the State Geocadastre, with the assignment of individual identification numbers, which is the basic principle of the formation of individual electronic cadastral maps, has been developed. The information content of individual electronic cadastral maps has been supplemented with detailed and versatile data to optimize the methodology and organization of accounting for agricultural activities in connection with the management of agricultural enterprises. Difficulties in the inventory of land are revealed and ways of solving them are proposed through the establishment of reliable and timely accounting in the conditions of the use of individual cadastral maps. The accounting of agricultural activity in the section of land plots using geocadastral electronic maps has been improved in next ways: identification of production and general production costs for the cultivation of agricultural products; separation of responsibility centers and cost centers to establish the accountability of employees for the results of agricultural activities; secondary land inventory with the help of satellite, aerial visual monitoring by drones and documentary appeals to state electronic registers; control over the condition of the soil and accounting for the damage caused on the basis of agrochemical certification of land allotments, etc.Perspectives. The use of individual electronic cadastral maps in accounting forms a unique base of versatile and detailed micro-level data necessary for optimization of agricultural management. The use of satellite positioning and aerial visual monitoring systems in accounting for agricultural activity requires avoiding significant methodological and organizational limitations, which is the subject of further scientific and practical research.

Visualization Techniques via MLBS for Personnel Management in Major Events

Mobile location-based services (MLBS) refer to services around geographic location data. Mobile terminals use wireless communication networks (or satellite positioning systems) to obtain users’ geographic location coordinate information based on spatial databases and integrate with other information to provide users with required location-related services. The development of systems based on MLBS has significance and practical value. In this paper a visualization management information system for personnel in major events based on microservices, namely MEPMIS, is designed and implemented by using MLBS. The system consists of a server and a client app, and it has some functions including map search and query, personnel positioning and scheduling, location management, messaging, and location service. Managers of the events can quickly search and locate the staff on the specific area of the map in real-time, and make broadcasting messages to the staff, and manage the staff. The client app is developed on the Android system, by which staff users can send the positions information to the server timely. The client users can search fuzzily near their peers and list their locations, and also call near peers through sending messages or query the history record of staff locations. In the design of the system, several new proposed techniques, including visual annotation method for overlapping locations, correcting trajectory drift algorithm, microservices-based overall system architecture methodology and other new techniques, which are applied to the implementation of the system. Also, HTML5, JQuery, MLBS APIs (Application Program Interfaces) related programming techniques have been used and combined with loading Ajax asynchronously and Json data encapsulation, map marker optimization techniques, that can improve the positioning accuracy and the performance of the system. The developed system with practical functions can enhance the efficiencies of the organization and management of major events.

Accuracy of topographical instruments and Unmanned Aerial Systems for mapping and surveying environmental projects.

For the implementation of environmental technical projects, such as the urban forest management, a key element is the topographical and cartographic mapping of the area. Topographical instruments are based on digital, aerial or satellite information’s that can be used for producing topographical maps. This research aims to highlight that UAVs in combination with low-cost survey methods, produce topographical mapping with accepted accuracy for the implementation of environmental projects, how we can survey a road network in order to produce digital topographic maps and also how the implementation of four different ways of measuring can help us to accomplish it. The methods for executing topographic projects differ in quality, accuracy, time and cost. The results of surveying with a total station, a binary satellite positioning system, a handheld satellite positioning system and an unmanned aerial system were compared based on the accuracy of the results. Estimation of measurement error combined by the time required and the cost of each instrument and associated software for data processing were estimated. The results obtained prove that low-cost methods give sufficient and acceptable accuracy; especially the Unmanned Aerial Systems, are capable of being used for the design and implementation of forest urbanization studies.

Exploring external load variations in elite female soccer players during 6v6 small-sided games

Purpose: The aim of this study was to describe and compare the external loads response of elite female soccer players to different small-sided games (SSG). Twelve elite female soccer players (26.5 ± 5.7 years, 58.6 ± 5.6 kg, 164.4 ± 5.3 cm) performed four different 6vs6 SSG: two different sizes (20x20m and 30x30m) and with minigoals (MG) and without mini-goals (NG). Methods: Total distance (TD), low-intensity running distance (LIR), high-intensity running distance (HIR), sprint distance (SD), accelerations (ACC), decelerations (DEC), repeated sprints (RS) and Bodyload (BL) was collected using a 15Hz global positioning satellite system. The variables were compared across all SSG formats using a one-way analysis of variance (ANOVA) (p<.05) and non-clinical magnitude-based inferences (Cohen´s d). Results: Compared to 20x20m SSG, the 30x30m SSG induced greater TD (p=.001, d=1.20), LIR (p=.001, d=1.06), HIR (p=.001, d=1.20) and BL (p=.008, d=1.04) in NG condition. Similarly, in SSG with MG, greater number of ACC (p=.003, d=.38), DEC (p=.005, d=.42), LIR (p=.009, d=.86) and HIR (p=.070 d=.61) occurred in 30x30m vs. 20x20m. When NG 30x30m and 20x20m SSG were played, greater TD (p=.001, d=1.70; p=.001, d=1.13; respectively), LIR (p=.001, d=1.84; p=.001, d=1.39), ACC (p=.54, d=.39; p=.003, d=.74; respectively) and BL (p=.001, d=1.60; p=.001, d=1.15; respectively) were noted compared to MG. Conclusion: greater external load response of elite female soccer players was observed in SSG without mini-goals and played in greater pitch sizes. These findings are usefulness for coaches and physical trainers to design proper training tasks according to game demands.

UAV Attitude Angle Measurement Method Based on Magnetometer-Satellite Positioning System

To improve the measurement accuracy of unmanned aerial vehicles (UAVs), in this study, we proposed a method for measuring the attitude angle of a UAV by the combination of a magnetometer and satellite positioning system. Based on the measurement principle, we established a combined measurement error model, analyzed the root cause of the measurement error, and calibrated the magnetometer using the least-squares algorithm. For handling external or system interference effects, we designed a compensation algorithm that does not depend on environmental information. For handling measurement errors, a “current” statistical model was established, and the continuous-discrete Kalman filter algorithm was used to eliminate measurement errors. The test results showed that after using the compensation algorithm, the measurement error was reduced from 17.80% to 6.86% compared to the average absolute error of the local magnetic field intensity, and the absolute measurement error was reduced by 61.49%. The absolute measurement error was compared after using the compensation + filtering algorithm, and the error after compensation was further reduced by 42.36%. Hence, we proved the feasibility and effectiveness of our method.

Research on Improving Satellite Positioning Precision Based on Multi-Frequency Navigation Signals.

In satellite positioning systems, optimizing navigation satellite constellation and reducing the observation residuals are usually adopted to improve positioning precision and accuracy of the receiver. This paper presents a method to improve positioning precision by using multi-frequency navigation signals. The observation data of CAPS and GPS system are used to simulate the experiment. When the number of downlink frequencies is different, the root mean square of positioning error, improvement percentage, and standard deviation are calculated, respectively. When the number of descending frequencies is k, the root mean square of positioning error in three-dimensional space is 1/ of that in single frequency. The theoretical derivation and experiment show that the precision of satellite positioning can be effectively improved by using multi-frequency navigation signals. The research work can provide theoretical support and data reference for the future research of satellite positioning.

Assessment of the performance of GPS/Galileo PPP-RTK convergence using ionospheric corrections from networks with different scales

The rapid convergence of precise point positioning real-time kinematics (PPP-RTK) with centimeter-level accuracy is of utmost importance for many applications. One way of accelerating this convergence is to explore the use of ionospheric models and multiple global navigation satellite system (GNSS) observations, e.g., Global Positioning System (GPS) and Galileo Satellite Navigation System (Galileo) observations. Because the temporal and spatial variations of the ionosphere are significant, convergence analysis of PPP-RTK should be investigated in networks with different scales, especially networks with large differences in their scales. This study describes the convergence performance of PPP-RTK using GPS/Galileo observations derived from networks with different scales under medium ionospheric conditions. Slant ionospheric corrections were first estimated from the reference network and then imported as virtual observations to enhance the convergence performance of PPP-RTK at the user interface. The results show that for the 165-km reference site spacing, the portions of single-differenced (SD) ionospheric residuals within 0.3 total electron content units (TECU) were 85.2% and 81.7% for the GPS and Galileo observations, respectively. Considering the 90th percentile of horizontal position errors, the PPP-RTK convergence time within the network with 165-km spacing was shortened from 2.5 min for GPS-only observations to 2.0 min for integrated GPS + Galileo observations. For the network of about 50 km, the proportions of the SD ionospheric residuals of the GPS and Galileo constellation within 0.3 TECU were 95.9% and 82.8%, respectively. The PPP-RTK convergence time of the 90th percentile horizontal positioning errors based on GPS-only observations was 2.0 min but 1.5 min based on integrated GPS + Galileo observations. Using GPS and Galileo observations, the convergence time could be reduced by 25% for the network with 50-km spacing. Our results suggest that the convergence time of PPP-RTK depends on the scale of the reference network and becomes shorter as the scale of the network decreases. Compared with the GPS-only PPP-RTK, the GPS/Galileo PPP-RTK could shorten the convergence time further.Graphical

The Advantages and Limitations of Low-Cost Single Frequency GPS/MEMS-Based INS Integration

Global Positioning System (GPS) provides a method for directly obtaining instantaneous position and velocity estimates using satellites-based passive range measurements. GPS is a whole day, all-weather, passive, satellite positioning system. Inertial Navigation System (INS) is a navigation aid system that uses a computer and Inertial Measurement Unite (IMU). IMU includes motion sensors and rotation sensors to continuously calculate relative position, orientation, and velocity. The integration of GPS/INS can help to overcome the limitations of the two systems providing integrated system better than either on a stand-alone basis. The integration of low-cost INS with dual frequency GPS has been widely studied and the same for the integration of tactical grid INS with low-cost GPS. However, during the last a few years, a number of low-cost GPS\low-cost INS integrated systems have been introduced and become popular in various engineering applications. However, reliable investigations into the advantages, limitations and quality of such integration level are still needed and more efforts are required, which will be the focus of this paper. The methodology followed in this paper for evaluating the integration of low-cost GPS/INS sensors depends on evaluating the two sensors individually and comparing the results with the integrated system. The results show that low-cost single frequency GPS receivers are able to provide a comparable accuracy level in both static and kinematic carrier phase differential GPS (DGPS). As for low-cost Micro-Electro-Mechanical System (MEMS)-based IMU, the accelerometers have provided instability comparing to gyros. The performance of gyros can be improved based on modelling the nearly-linear behaviour of the gyro drift. Tests show that the integration of low-cost GPS sensors with MEMS-based INS degrades the quality of gyro measurements and may not add any improvements to the quality of the individual GPS positioning.