Journal articles: 'Artificial satellites'

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Yifei, Xie. "Research on the development of artificial satellites." Theoretical and Natural Science 30, no. 1 (January 15, 2024): 275–79. http://dx.doi.org/10.54254/2753-8818/30/20241136.

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This paper aims to systematically explore the development history, current situation, and future trends of artificial satellites, and to comprehensively analyze the important role of artificial satellites in national science and technology, national defense, and economic construction. Firstly, the paper outlines the extensive applications of artificial satellites as an important component of modern aerospace technology in fields such as communication, navigation, meteorology, and earth observation, as well as their significant importance for national security and economic development. Secondly, this paper adopts the research methods of literature review and case analysis to systematically study the latest progress and achievements in artificial satellite technology in various countries around the world and deeply analyzes the key technological breakthroughs and current development status of China in remote sensing, navigation, communication and other fields. Finally, through an in-depth analysis of the development trends and challenges faced by artificial satellite technology, combined with the current development status of Chinas aerospace industry, strategies and suggestions for the future development of artificial satellite technology in China are proposed. This study can provide theoretical support for the research and application of artificial satellite technology in China, and help promote the sustained and healthy development of Chinas aerospace industry.

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Schutz, B. E. "New Observational Techniques and Precise Orbit Determination of Artificial Satellites." International Astronomical Union Colloquium 165 (1997): 79–85. http://dx.doi.org/10.1017/s025292110004639x.

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AbstractModern observational techniques using ground-based and space-based instrumentation have enabled the measurement of the distance between the instrument and satellite to better than one centimeter. Such high precision instrumentation has fostered applications with centimeter-level requirements for satellite position knowledge. The determination of the satellite position to such accuracy requires a comparable modeling of the forces experienced by the satellite, especially when classical orbit determination methods are used. Geodetic satellites, such as Lageos, in conjunction with high precision ground-based laser ranging, have been used to improve for modeling of forces experienced by the satellite. Space-based techniques, such as Global Positioning System (GPS), offer alternatives, including kinematic techniques which require no modeling of the satellite forces, or only rudimentary models. This paper will describe the various techniques and illustrate the accuracies achieved with current satellites, such as TOPEX/POSEIDON, GPS/MET and the expectations for some future satellites.

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MATSUNAGA, Saburo. "Very Small Artificial Satellites." Journal of the Society of Mechanical Engineers 108, no. 1042 (2005): 708–9. http://dx.doi.org/10.1299/jsmemag.108.1042_708.

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Saiko, Volodymyr, Teodor Narytnyk, Valeriy Gladkykh, and Natalia Sivkova. "INNOVATIVE SOLUTION FOR LEO-SYSTEM WITH DISTRIBUTED SATELLITE ARCHITECTURE." Information systems and technologies security, no. 1 (2) (2020): 77–83. http://dx.doi.org/10.17721/ists.2020.1.77-83.

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An innovative solution for practical implementation in a LEO system with a "distributed satellite" architecture that can be used to provide low-orbital spacecraft communications with ground stations and users of 5G / IoT satellite services is proposed. The essence of the proposed development in the system of low-orbital satellite communication with FC-architecture is that to reduce the delay in signaling to consumers and the probability of overloading the network into a prospective system of low-orbital satellite communication, which contains artificial Earth satellites, each of which functions in Earth orbit and equipped with onboard repeaters, inter-satellite communications, a network of ground-based communication and control systems for artificial satellites of the Earth, a grouping of low-orbiting space their devices (LEO-system), which includes the grouping of root (leading) satellites and satellites-repeaters (slave), around each root satellite is formed micro-grouping of satellites-repeaters, and functions of the root satellite in the selected orbital phase of the orbital -or micro-satellites that are connected to the annular network by communication lines between satellites, and - functions of satellites-repeaters - kubsat, new is the introduction of a multilevel boundary cloud system, which is a heterogeneity distributed computing cloud structure. At the same time, the boundary clouds of the multilevel system are connected by ultra-high-speed wireless terahertz radio lines and wireless optical communication systems. The technique of estimation of access time in the proposed structure of "fog computing" on the basis of the model of access in "fog computing" with the resolution of collisions of data sources implementing the survey mode is presented.

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KUDO, ISAO. "Satellite Technology in Space Age. Commercialization of Artificial Satellites." Journal of the Institute of Electrical Engineers of Japan 118, no. 4 (1998): 206–9. http://dx.doi.org/10.1541/ieejjournal.118.206.

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Olukunle Kolawole, Soyinka, and Duan Haibin. "Satellite formation keeping via chaotic artificial bee colony." Aircraft Engineering and Aerospace Technology 89, no. 2 (March 6, 2017): 246–56. http://dx.doi.org/10.1108/aeat-02-2014-0019.

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Purpose Keeping satellite position within close tolerances is key for the utilization of satellite formations for space missions. The presence of perturbation forces makes control inevitable if such mission objective is to be realised. Various approaches have been used to obtain feedback controller parameters for satellites in a formation; this paper aims to approach the problem of estimating the optimal feedback parameter for a leader–follower pair of satellites in a small eccentric orbit using nature-based search algorithms. Design/methodology/approach The chaotic artificial bee colony algorithm is a variant of the basic artificial bee colony algorithm. The algorithm mimics the behaviour of bees in their search for food sources. This paper uses the algorithm in optimizing feedback controller parameters for a satellite formation control problem. The problem is formulated to optimize the controller parameters while minimizing a fuel- and state-dependent cost function. The dynamical model of the satellite is based on Gauss variational equations with J2 perturbation. Detailed implementation of the procedure is provided, and experimental results of using the algorithm are also presented to show feasibility of the method. Findings The experimental results indicate the feasibility of this approach, clearly showing the effective control of the transients that arise because of J2 perturbation. Originality/value This paper applied a swarm intelligence approach to the problem of estimating optimal feedback control parameter for a pair of satellites in a formation.

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Bordovitsyna, T. V., and N. A. Sharkovsky. "On calculation of relativistic effects in numerical prediction of the artificial satellite motion." Symposium - International Astronomical Union 114 (1986): 283–88. http://dx.doi.org/10.1017/s0074180900148302.

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This paper discussed the algorithm of the calculation of relativistic effects in numerical prediction of the artificial satellites motion. An attempt to estimate the values of relativistic effects in the motion of two artificial satellites Navstar and Lageos is made. These values are compared with the quantities of other weak perturbations and the errors of the calculated position of the satellite due to the inaccurate approximation of perturbations.

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Ammar, M. K., M. R. Amin, and M. H. M. Hassan. "Visibility intervals between two artificial satellites under the action of Earth oblateness." Applied Mathematics and Nonlinear Sciences 3, no. 2 (July 5, 2018): 353–74. http://dx.doi.org/10.21042/amns.2018.2.00028.

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AbstractThis paper presents an analytical method to determine the rise-set times of satellite-satellite visibility periods in different orbits. The Visibility function in terms of the orbital elements of the two satellites versus the time were derived explicitly up to e4. The line-of-sight corrected for Earth Oblateness up to J2, were considered as a perturbation to the orbital elements. The visibility intervals of the satellites were calculated for some numerical examples in order to test the results of the analytical work.

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Y. CH BISSA, Stevry, Ibnu Nurul Huda, Muhammad Bayu Saputra, Sofian Rizal, Ridlo W. Wibowo, and Farahhati Mumtahana. "Development of artificial Earth satellite simulation software for future radio telescopes in Indonesia." Romanian Astronomical Journal 33, no. 1-2 (December 12, 2023): 3–14. http://dx.doi.org/10.59277/roaj.2023.1-2.01.

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"In the near future, four radio telescopes will be installed in Indonesia. Besides the astronomical purposes, these telescopes are expected to support the ground station for tracking the Artificial Earth Satellites (AES). In this study, we focus on the development of AES simulation software, named AESSIMS, that can be used to aid Indonesian radio telescope engineers in tracking the AES. This software is interactive and web-based. It can track the AES position in real time as well as predict the position for the near future. This software provides information about when a satellite signal can be acquired and lost, which can be beneficial for radio telescopes to establish communication with the satellite. We visualize the use of this software by conducting a simulation of satellite tracking by Indonesian future radio telescopes. Three Indonesian satellites named LAPAN-A1/TUBSAT, LAPAN-A2/ORARI, and LAPAN-A3/IPB are considered in the simulation. This study demonstrates that AESSIMS simulation results for Indonesian satellites and radio telescopes are consistent with the results obtained from already existing satellite tracking simulation software."

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Romashkina, Nataliya. "SPACE AS PART OF THE GLOBAL INFORMATION SPACE DURING MILITARY OPERATIONS." Voprosy kiberbezopasnosti, no. 6(52) (2022): 100–111. http://dx.doi.org/10.21681/2311-3456-2022-6-100-111.

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Purpose: To identify the current possibilities of the use of artificial earth satellites for military purposes, as well as the problems of illegal destructive use of satellites during hostilities based on analysis and systematization according to various parameters of functions of satellites as part of the modern global information space and to develop proposals that can reduce the likelihood of escalation of the conflict during the crisis. Research method: analysis of open sources on the purposeful use of modern AES, synthesis and scientific forecasting, expert assessment, factological analysis of the AES within the framework of a systematic approach. Result: the article presents an analysis and systematization significant dynamic changes at the cosmic level of the global information space associated with the large-scale spread and significant increase in the number of artificial earth satellites, as well as with the growing importance of satellites for military purposes. The article pres- ents the classification of satellites performing military functions, reveals the possibilities of modern satellites in the period of crisis and military operations and the analysis of the US satellite constellation as a leader in this field. The author poses the problems of the illegal destructive use of artificial earth satellites during military conflicts, as- sociated with this increase in the risk of cyber threats and an increase in the likelihood of escalation of the conflict, threats to Russia, international security and strategic stability. The article proves the quantitative and qualitative characteristics of the satellite constellation are today one of the most important indicators of the influence and potential of the state in the world. Scientific novelty: Proposals have been developed to minimize threats to Russia, as well as to reduce the likeli- hood of an escalation of the conflict during the crisis.

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Moorhead, Simon. "Radio Communication By Artificial Satellites." Journal of Telecommunications and the Digital Economy 3, no. 3 (September 28, 2015): 72–84. http://dx.doi.org/10.18080/jtde.v3n3.12.

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A remarkable paper from 1961 which demonstrates the Post Master General’s Department was at the forefront of technological developments concerning radio communications by artificial satellites before the launch of Telstar.

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Sampaio, Jarbas C., Rodolpho Vilhena de Moraes, and Sandro S. Fernandes. "Artificial satellites dynamics: resonant effects." Journal of Aerospace Engineering, Sciences and Applications 4, no. 2 (April 1, 2012): 1–14. http://dx.doi.org/10.7446/jaesa.0402.01.

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Giorgio Eugenio Oscare, Giacaglia. "RELATIVISTIC EFFECTS ON ARTIFICIAL SATELLITES." Engineering Research: technical reports 3, no. 1 (2012): 1–19. http://dx.doi.org/10.32426/engresv3n1-001.

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Vovchyk, Yeva, Yaroslav Blagodyr, Gennadiy Kraynyuk, Andriy Bilinsky, Alexander Lohvynenko, Bogdan Klym, and Yevhen Pochapsky. "Electrophotometric observations of artificial satellites." Journal of Quantitative Spectroscopy and Radiative Transfer 88, no. 1-3 (September 2004): 211–17. http://dx.doi.org/10.1016/j.jqsrt.2004.01.008.

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Hidri, Lotfi, Mehdi Mrad, and Mohammed Alkahtani. "Suitable Mass Density Function for an Artificial Satellite to Prevent Chaotic Motion after Collision with Space Debris." Symmetry 14, no. 4 (April 14, 2022): 818. http://dx.doi.org/10.3390/sym14040818.

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Artificial satellites are widely used in different areas such as communication, position systems, and agriculture. The number of satellites orbiting Earth is becoming huge, and many are set to be launched soon. This huge number of satellites in addition to space debris are sources of concern. Indeed, some incidents have occurred either between satellites or because of space debris. These incidents are a threat for the hit satellite and can be a source of irreversible damages. A hit satellite may diverge to a chaotic motion with all the entailed consequences. The inertia moment of a satellite is a main factor to determine if the hit satellite is heading toward a chaotic motion or not. The inertia moment is determined over the mass density function. In this paper, a circularly orbiting artificial satellite was modeled as a thin rotating rod. The objective was to determine a suitable mass density function for this satellite allowing the prevention as much as possible of the chaotic motion after being hit. This unknown density mass function satisfies a system of equations reflecting some physical constraints. Conventional procedures are not applicable to solve this system of equations. The presented resolution method is based on several mathematical transformations, allowing converting this system into a highly nonlinear one with several unknowns. Several mathematical techniques were applied, and an analytical solution was obtained. Finally, from the mechanical engineering point of view, the obtained mass density function corresponds to a Functionally Graded Material (FGM).

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Alluhaybi, Abdulaziz, Panos Psimoulis, and Rasa Remenyte-Prescott. "An Evaluation of Optimization Algorithms for the Optimal Selection of GNSS Satellite Subsets." Remote Sensing 16, no. 10 (May 18, 2024): 1794. http://dx.doi.org/10.3390/rs16101794.

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Continuous advancements in GNSS systems have led, apart from the broadly used GPS, to the development of other satellite systems (Galileo, BeiDou, GLONASS), which have significantly increased the number of available satellites for GNSS positioning applications. However, despite GNSS satellites’ redundancy, a potential poor GNSS satellite signal (i.e., low signal-to-noise ratio) can negatively affect the GNSS’s performance and positioning accuracy. On the other hand, selecting high-quality GNSS satellite signals by retaining a sufficient number of GNSS satellites can enhance the GNSS’s positioning performance. Various methods, including optimization algorithms, which are also commonly adopted in artificial intelligence (AI) methods, have been applied for satellite selection. In this study, five optimization algorithms were investigated and assessed in terms of their ability to determine the optimal GNSS satellite constellation, such as Artificial Bee Colony optimization (ABC), Ant Colony Optimization (ACO), Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and Simulated Annealing (SA). The assessment of the optimization algorithms was based on two criteria, such as the robustness of the solution for the optimal satellite constellation and the time required to find the solution. The selection of the GNSS satellites was based on the weighted geometric dilution of precision (WGDOP) parameter, where the geometric dilution of precision (GDOP) is modified by applying weights based on the quality of the satellites’ signal. The optimization algorithms were tested on the basis of 24 h of tracking data gathered from a permanent GNSS station, for GPS-only and multi-GNSS data (GPS, GLONASS, and Galileo). According to the comparison results, the ABC, ACO, and PSO algorithms were equivalent in terms of selection accuracy and speed. However, ABC was determined to be the most suitable algorithm due it requiring the fewest number of parameters to be set. To further investigate ABC’s performance, the method was applied for the selection of an optimal GNSS satellite subset according to the number of total available tracked GNSS satellites (up to 31 satellites), leading to more than 300 million possible combinations of 15 GNSS satellites. ABC was able to select the optimal satellite subsets with 100% accuracy.

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Romashkina, Nataliya. "US Satellites during the Crisis: Outer Space Cyber Threats." Vestnik of Saint Petersburg University. International relations 17, no. 1 (2024): 59–76. http://dx.doi.org/10.21638/spbu06.2024.104.

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Against the background of significant dynamic changes in the use of outer space by mankind, the transformation of outer space into a sphere of military confrontation becomes not a danger of the distant future, but a real urgent threat. Important characteristics of the current stage are the ubiquity and significant growth in the number of artificial Earth satellites, which solve more and more research and applied tasks, as well as the steady increase in the importance of applied satellites used for military purposes. The most important role among them is played by communication satellites, navigation, remote sensing of the Earth (remote sensing), as well as satellites of the Early warning system. In the course of military operations, artificial Earth satellites serve to ensure combat operations and the combat use of various means of armed struggle. The United States has the largest satellite grouping. The analysis presented in the article of the capabilities of modern US artificial satellite systems, as well as their destructive use during a military conflict, allows us to conclude that the risk of threats to international security is increasing. In addition, the facts of the destabilizing use of artificial satellites by the United States of America and other NATO countries to achieve their military and political goals increase the likelihood of an escalation of the conflict and are associated at the current stage with threats to Russia and strategic stability. Against the background of other urgent challenges and threats, this poses a number of global problems posed in this study as acutely as possible. The article presents the characteristics of the current stage of space use; the possibilities of the US ISP during the crisis, which serve to provide various means of armed struggle, are identified; the problems of using the US ISP in the current situation are posed. Proposals have been developed to minimize threats and reduce the likelihood of escalation of the conflict.

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Houlahan, Padraig. "Tracking artificial satellites with the Macintosh." Computers in Physics 8, no. 1 (1994): 113. http://dx.doi.org/10.1063/1.168513.

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Paulo dos Santos Carvalho, Jean, Rodolpho Vilhena de Moraes, and Antônio Fernando Bertachini de Almeida Prado. "Dynamics of Artificial Satellites around Europa." Mathematical Problems in Engineering 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/182079.

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A planetary satellite of interest at the present moment for the scientific community is Europa, one of the four largest moons of Jupiter. There are some missions planned to visit Europa in the next years, for example, Jupiter Europa Orbiter (JEO, NASA) and Jupiter Icy Moon Explorer (JUICE, ESA). In this paper, we search for orbits around Europa with long lifetimes. Here, we develop the disturbing potential in closed form up to the second order to analyze the effects caused on the orbital elements of an artificial satellite around Europa. The equations of motion are developed in closed form to avoid expansions in power series of the eccentricity and inclination. We found polar orbits with long lifetimes. This type of orbits reduces considerably the maintenance cost of the orbit. We show a formula to calculate the critical inclination of orbits around Europa taking into account the disturbing potential due to the nonspherical shape of the central body and the perturbation of the third body.

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Smith, D. A., and D. C. Hill. "Imaging artificial satellites: An observational challenge." Physics Teacher 54, no. 7 (October 2016): 444–45. http://dx.doi.org/10.1119/1.4962790.

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Li, Yuheng. "Optical and structural designs for GEO orbit remote-sensing satellite and its camera system." Theoretical and Natural Science 26, no. 1 (December 20, 2023): 215–20. http://dx.doi.org/10.54254/2753-8818/26/20241070.

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Since 1957, when the Soviet Union launched the first artificial satellite, Sputnik I, attempts have been made to bring convenience to people by interacting with terrestrial facilities through orbital space. Geostationary Earth-orbiting remote sensing satellites provide the ability to continuously scan and explore a specific area, allowing researchers to obtain more accurate information about the Earth, which benefits mankind in many ways. This paper analyzes the payload satellite camera carried by remote sensing satellites, explains the working principle of the camera, and outlines the relevant parameters and their concepts. Taking China's Gaofen-4 as an example, it analyzes the design and limitations of the common satellite camera used in this template from the perspectives of thermodynamic, mechanical, and optical environments. Meanwhile, the article gives an outlook on the future development trend of Geostationary Earth orbit remote sensing satellites.

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Frohloff, Jan. "Collisions of Artificial Satellites: The Liability of States and Private Entities." Air and Space Law 45, Issue 3 (June 1, 2020): 341–58. http://dx.doi.org/10.54648/aila2020042.

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With increased traffic in the orbits around Earth comes an increase in the probability that two operational spacecraft will collide or that one will be hit by junk such as decommissioned satellites, rocket stages or their fragments. If a satellite suffers damage from a collision or has to be declared a complete loss, the affected commercial spacecraft operator will try to recover its losses. But from whom? The Outer Space Treaty and the Liability Convention were not drafted for the commercial space era and will help the commercial operator only little, if at all. This article examines the claims a commercial spacecraft operator can pursue, including the possible fora in which these claims can be brought. Collisions, Spacecraft, Satellites, Space Debris, Liability, Jurisdiction

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Schildknecht, T., I. Bauersima, U. Hugentobler, A. Verdun, and G. Beutler. "CQSSP: A New Technique for Establishing the Tie Between the Stellar and Quasar Celestial Reference Frames." International Astronomical Union Colloquium 127 (1991): 341–47. http://dx.doi.org/10.1017/s0252921100064174.

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AbstractUsing artificial satellites as transfer objects the project “Coupled Quasar-Satellite-Star Positioning” represents an independent method for linking quasar and stellar reference frames. Optical observations of close approaches between reference stars and satellites yield satellite positions in the stellar reference frame. On the other hand high precision satellite orbits in the International Earth Rotation Service (IERS) terrestrial reference frame are obtained from laser or radiometric observations. Using IERS earth rotation parameters and adopted transformation models the satellite and eventually the star positions can be expressed in the IERS quasar celestial reference frame. In this paper we describe the CQSSP project and assess its capability for providing an accurate tie between tho two metioned celestial reference frames.

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da Costa, Maria Lívia G. T. X., Rodolpho Vilhena de Moraes, Jean Paulo S. Carvalho, and Antônio Fernando B. A. Prado. "Artificial satellites orbiting planetary satellites: critical inclination and sun-synchronous orbits." Journal of Physics: Conference Series 911 (October 2017): 012018. http://dx.doi.org/10.1088/1742-6596/911/1/012018.

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Neiman, Yu M., and L. S. Sugaipova. "GNSS orbit approximation by means of artificial neural networks." Geodesy and Cartography 1007, no. 5 (June 20, 2024): 11–23. http://dx.doi.org/10.22389/0016-7126-2024-1007-5-11-23.

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The possibilities of using artificial neural networks (ANN) to approximate and extrapolate the orbits of GNSS satellites (global navigation satellite systems) are explored. Numerical experiments are performed using radial basis function networks (RBFN), as they are trained quickly enough and convenient for working with a small amount of data. The results show that RBFN successfully handle both interpolation and short-term satellite orbit prediction (extrapolation) and have notable advantages over traditionally used polynomial methods both in terms of accuracy achieved, and the speed of calculations. In particular, it is possible to use a single neural network to interpolate (extrapolate) all components of the location, while the standard approach requires a separate polynomial for each satellite coordinate

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Najder, Joanna, and Krzysztof Sośnica. "Quality of Orbit Predictions for Satellites Tracked by SLR Stations." Remote Sensing 13, no. 7 (April 3, 2021): 1377. http://dx.doi.org/10.3390/rs13071377.

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This study aims to evaluate and analyze the orbit predictions of selected satellites: geodetic, Global Navigational Satellite Systems (GNSS), and scientific low-orbiting, which are tracked by laser stations. The possibility of conducting satellite laser ranging (SLR) to artificial satellites depends on the access to high-quality predictions of satellite orbits. The predictions provide information to laser stations where to aim the telescope in search of a satellite to get the returns from the retroreflectors installed onboard. If the orbit predictions are very imprecise, SLR stations must spend more time to correct the telescope pointing, and thus the number of collected observations is small or, in an extreme case, there are none of them at all. Currently, there are about 120 satellites equipped with laser retroreflectors orbiting the Earth. Therefore, the necessity to determine the quality of predictions provided by various analysis centers is important in the context of the increasing number of satellites tracked by SLR stations. We compare the orbit predictions to final GNSS orbits, precise orbits of geodetic satellites based on SLR measurements determined in postprocessing, and kinematic orbits of low-orbiting satellites based on GPS data. We assess the quality degradation of the orbit predictions over time depending on the type of orbit and the satellite being analyzed. We estimate the time of usefulness of prediction files, and indicate those centers which publish most accurate predictions of the satellites’ trajectories. The best-quality predictions for geodetic satellites and Galileo reach the mean error of 0.5–1 m for the whole 5-day prediction file (for all three components), while the worst ones can reach values of up to several thousand meters during the first day of the prediction.

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Łukasiewicz, Jerzy, Joanna Lubieniecka, Jerzy Kusiński, Wiesław Sarna, and Krzysztof Tchórznicki. "The Automated System of Optical Observation and Tracking of Space Objects." Journal of KONBiN 50, no. 1 (March 1, 2020): 237–58. http://dx.doi.org/10.2478/jok-2020-0014.

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AbstractHaving a fleet of artificial satellites necessitates the construction of a system that will enable obtaining information on the situation in the Earth orbit (Space Situation Awareness - SSA). Such systems are built either as active radar systems or as passive optical systems. The automated system of optical observation and tracking of space objects (ASOPEK) consists of two optical systems (wide-angle and narrow-angle) and software enabling: detection of artificial satellites in the field of view of the system, identification of detected objects, updating the satellite database with unknown objects, updating orbits of observed objects. The ASOPEK system was created as part of a project financed by the National Center for Research and Development No. DOB-BIO7/25/02/2015.

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Komendant, V. H. "ON THE CHARACTER OF AN ARTIFICIAL SATELLITE DRAG UNDER VARIOUS STATES OF SOLAR AND GEOMAGNETIC ACTIVITY." Radio physics and radio astronomy 25, no. 4 (December 2, 2020): 308–23. http://dx.doi.org/10.15407/rpra25.04.308.

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Purpose: The artificial satellites drag in the atmosphere remains an urgent problem to date. In this work, the artificial satellites data are used in order to study the atmosphere state under various manifestations of solar and geomagnetic activity. The selected satelites were moving uncontrollable being good indicators of the upper atmosphere state. The B-star (drag term) drag coefficient is used in this work. This term is used in the SGP and SDP models to take into account the resistance of the atmosphere to the satelite orbital motion. The data of the drag of two artificial satellites, one moving in elliptical and the other in circular orbits at midlatitudes (orbital plane angles of 58°-60°) were considered. These data include the end of the 23rd solar activity cycle, as well as the growth, the maximum and the decay phases of the 24th solar cycle (years 2005–2017). Seven periods of anomalous drag of the satellites were analyzed. They are: 4 monthly periods (two in 2005 and two in 2011) and 3 yearly periods (within 19.07.2014 to 22.08.2015), five-year long (2005–2010) and six-year long (2011–2017) periods. Design/methodology/approach: The periodogram analysis was made. This allowed to reveal the periodic processes in changes in the state of the atmosphere of different duration. The correlation coefficients of the B-star drag term with the indices of solar and geomagnetic activity were calculated. The analysis of extreme drag of the satellites in the periods of the increased solar and geomagnetic activity (intervals of observation lasting a month) was made. Findings: Using the solar and geomagnetic data we found that some month-long part of the anomalous drag periods were followed by flares on the Sun and the arrival of the coronal mass ejections into the near-Earth space. At time intervals of yearlong observations the highest values (0.5-0.7) were obtained for the coefficients of the B-star parameter correlation with the solar activity indices – solar radiation at the wavelength of 10.7 cm, F10.7, and Lyman alpha radiation, Lα. At monthly time intervals, the largest values of the correlation coefficients were obtained for the B-stars with the electron fluxes with energies above 0.6 and 2 MeV, E, (0.3-0.5), the Lyman alpha radiation, Lα, (0.58–0.73 for a сircular orbit satellite), and the solar constant, TSI, (0.3–0.6), as well as the geomagnetic storms intensity index, Dst , (0.66–0.69). Periodogram calculations show the presence of a whole spectrum of periods in the deceleration of a circular orbit satellite and a dedicated period for an elliptical orbit satellite. Conclusions: The B-star drag term dependences on the indices of solar and geomagnetic activity during some periods of their intensification for the 23–24 cycles of solar activity are considered. The periodogram analysis made together with the analysis of the conditions and parameters of space weather allows to see the general and more detailed picture of the solar and geomagnetic activity influence on the change in the motion of the satellite in the atmosphere. The B-star drag term helps to consider only the atmosphere influence on the artificial satellite movement in the near-Earth space. Key words: artificial satellite, atmosphere, artificial satellite drag, solar activity, geomagnetic activity, space weather

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Maciuk, Kamil. "DOP coefficients in GNSS observations." Budownictwo i Architektura 14, no. 1 (March 10, 2015): 065–72. http://dx.doi.org/10.35784/bud-arch.1668.

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Integrated GNSS (GPS+GLONASS) satellite measurements carry a number of benefits. The main advantages are especially possibilities of conducting measurements in areas where use of a single satellite system was not impossible so far. In this paper number of visible satellites and DOP coefficients values in terms artificial horizon obstacles were analysed. Paper also discusses benefits of including additional observations from other navigation satellite systems.

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Kitamura, Mitsunori, Yoichi Yasuoka, Taro Suzuki, Yoshiharu Amano, and Takumi Hashizume. "Path Planning for Autonomous Vehicles Using QZSS and Satellite Visibility Map." Journal of Robotics and Mechatronics 25, no. 2 (April 20, 2013): 400–407. http://dx.doi.org/10.20965/jrm.2013.p0400.

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This paper describes a path planning method that uses the Quasi-Zenith Satellites System(QZSS) and a satellite visibility map for autonomous vehicles. QZSS is a positioning system operated by Japan that has an effect similar to an increase in the number of GPS satellites. Therefore, QZSS can be used to improve the availability of GPS positioning. A satellite visibility map is a special map that simulates the number of visible satellites at all points on the map. The vehicle can use the satellite visibility map to determine the points that receive more satellite signals. The proposed method generates the artificial potential fields from the satellite visibility map and obstacle information around the vehicle, and it generates the path following the potential fields. Thereby, the vehicle can select the path that has more satellite signals, improving the availability of GPS fixed solutions. Hence, the vehicle can reduce the accumulated error by dead reckoning, and it can improve the safety of self-control. In this study, we evaluate the satellite visibility maps and the path planning method. The results show that the proposed method does improve the availability of GPS fixed solutions.

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Krzysztof, Sośnica. "Impact of the Atmospheric Drag on Starlette, Stella, Ajisai, and Lares Orbits." Artificial Satellites 50, no. 1 (March 1, 2015): 1–18. http://dx.doi.org/10.1515/arsa-2015-0001.

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Abstract The high-quality satellite orbits of geodetic satellites, which are determined using Satellite Laser Ranging (SLR) observations, play a crucial role in providing, e.g., low-degree coefficients of the Earth's gravity field including geocenter coordinates, Earth rotation parameters, as well as the SLR station coordinates. The appropriate modeling of non-gravitational forces is essential for the orbit determination of artificial Earth satellites. The atmospheric drag is a dominating perturbing force for satellites at low altitudes up to about 700-1000 km. This article addresses the impact of the atmospheric drag on mean semi-major axes and orbital eccentricities of geodetic spherical satellites: Starlette, Stella, AJISAI, and LARES. Atmospheric drag causes the semi-major axis decays amounting to about ▲a = -1.2, -.12, -.14, and -.30 m/year for LARES, AJISAI, Starlette, and Stella, respectively. The density of the upper atmosphere strongly depends on the solar and geomagnetic activity. The atmospheric drag affects the along-track orbit component to the largest extent, and the out-of-plane to a small extent, whereas the radial component is almost unaffected by the atmospheric drag.

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Silva, W. R., M. C. Zanardi, J. K. S. Formiga, R. E. S. Cabette, and T. J. Stuchi. "Attitude stability analyses for small artificial satellites." Journal of Physics: Conference Series 465 (October 16, 2013): 012022. http://dx.doi.org/10.1088/1742-6596/465/1/012022.

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De Pontieu, B. "Database of photometric periods of artificial satellites." Advances in Space Research 19, no. 2 (January 1997): 229–32. http://dx.doi.org/10.1016/s0273-1177(97)00005-7.

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Cui Dou-xing. "A practical intermediate orbit for artificial satellites." Chinese Astronomy and Astrophysics 12, no. 2 (June 1988): 114–18. http://dx.doi.org/10.1016/0275-1062(88)90005-7.

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Tzirti, S., K. Tsiganis, and H. Varvoglis. "Quasi-critical orbits for artificial lunar satellites." Celestial Mechanics and Dynamical Astronomy 104, no. 3 (May 26, 2009): 227–39. http://dx.doi.org/10.1007/s10569-009-9207-4.

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Carvalho, J. P. S., R. Vilhena de Moraes, and A. F. B. A. Prado. "Some orbital characteristics of lunar artificial satellites." Celestial Mechanics and Dynamical Astronomy 108, no. 4 (October 9, 2010): 371–88. http://dx.doi.org/10.1007/s10569-010-9310-6.

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Kamiński, K., C. Weber, A. Marciniak, M. Żołnowski, and M. Gędek. "Reaching Submillisecond Accuracy in Stellar Occultations and Artificial Satellite Tracking." Publications of the Astronomical Society of the Pacific 135, no. 1044 (February 1, 2023): 025001. http://dx.doi.org/10.1088/1538-3873/acacc8.

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Abstract In recent years, there appeared a need for astronomical observations timed with submillisecond accuracy. These include, e.g., timing stellar occultations by small, subkilometer, or fast near-Earth asteroids and tracking artificial satellites in low-Earth orbit using optical sensors. Precise astrometry of fast-moving satellites and accurate timing of stellar occultations have parallel needs, requiring a reliable time source and good knowledge of camera delays. Thus, there is a need for an external device that would enable equipment and camera testing to check if they reach the required accuracy in time. We designed, constructed, and thoroughly tested a New EXposure Timing Analyser (NEXTA), a Global Navigation Satellite System–based precise timer allowing us to reach an accuracy of 0.1 ms, which is an order of magnitude better than in previously available tools. The device is a simple strip of blinking diodes to be imaged with a camera and compare the imaged time with the internal camera time stamp. Our tests spanned a range of scientific cameras widely used for stellar occultations and ground-based satellite tracking. The results revealed high reliability of both NEXTA and most of the tested cameras but also pointed out that practically all cameras had internal time biases of various levels. NEXTA can serve the community, being easily reproducible with inexpensive components. We provide all the necessary schemes and usage instructions.

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Zhang, Pengfei. "Research on satellite selection algorithm in ship positioning based on both geometry and geometric dilution of precision contribution." International Journal of Advanced Robotic Systems 16, no. 1 (January 1, 2019): 172988141983024. http://dx.doi.org/10.1177/1729881419830246.

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With the networking of four Global Navigation Satellite Systems, the combination of multi-constellation applications has become an inevitable trend, and there will be more and more visible satellites that can be participated in ship positioning. However, the computational complexity increases sharply, which greatly improves the load capacity of the receiver’s data processor and reduces the output frequency of the positioning result. To achieve the balance between positioning accuracy and computational complexity, a new fast satellite selection algorithm based on both of geometry and geometric dilution of precision contribution is proposed. Firstly, this article analyzes the geometry characteristics of the least visible satellites has minimum geometric dilution of precision that meet the positioning requirements and makes clear the layout of their elevation angles and azimuth angles. In addition, it derives the relationship of geometric dilution of precision and the visible satellites layout and gets geometric dilution of precision contribution of each satellite. Finally, based on the observation data of JFNG tracking station of the Multi-Global Navigation Satellite System (GNSS) Experiment trial network, the positioning error and the elapsed time of GPS/Beidou Satellite Navigation System and GPS/Beidou Satellite Navigation System/Russian Global Orbiting Navigation Satellite System (GLOANSS) are compared. Simulation results show that the algorithm solves the problem that there are a lot of matrix multiplications and matrix inversions in the traditional satellite selection algorithm, and the new algorithm can reduce computational complexity and increase receiver processing speed.

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Hrushytska, Iryna. "Vitaly Grigorevsky’s Contribution to the Development of International Cooperation in Photometric Studies of Artificial Earth Satellites." Acta Baltica Historiae et Philosophiae Scientiarum 8, no. 2 (December 10, 2020): 115–27. http://dx.doi.org/10.11590/abhps.2020.2.07.

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This article highlights the participation of the Ukrainian scientist, Professor Vitaly Mikhailovich Grigorevsky, doctor of physical and mathematical sciences, and representative of the scientific school of Vladimir Platonovich Tsesevich, in the organization and development of international cooperative partnership in the field of satellite astronomy and photometric studies of artificial satellites of the Earth. The activity of the scientist in the coordination of scientific research of the countries of Eastern Europe in 1965–1973 under the SPIN program, carried out under the auspices of the Astronomical Council of the USSR Academy of Sciences, is discussed. The article explores the main forms of Grigorevsky’s scientific cooperation with the world’s leading experts in the field of satellite astronomy—the British scientist Desmond King-Hele, the Czech astronomer František Link, Hungarian researchers Iván Almár and D. Toth, and others. Also, the achievements of the Latvian researchers Māris Ābele and Kasimirs Lapushka in the creation of photographic cameras of surveillance of satellites are analysed.

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Grace Mercy, M., A. Kamala Kumari, A. Bhujangarao, and V. Nooka Raju. "Ant Colony Optimization Algorithm GPS Clustering Approach." Journal of Physics: Conference Series 2040, no. 1 (October 1, 2021): 012011. http://dx.doi.org/10.1088/1742-6596/2040/1/012011.

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Abstract The geometry of the GPS satellite recipient (s), which reflects the recipient (s) of the satellites, has a major influence on the total positioning precision. The more precise the position, the stronger the geometry of the satellite. This article provides the geometry of satellite clustering for the selection of suitable satellite navigation subsets. This technique is based on the GDOP (Geometric Precision Dilution) satellite factor cluster with the Ant Colony Optimization (ACO) algorithm that has been created by simulating real and artificial ways to locate the quickest route between nesting resources and food. Pheromones are utilised in the suggested technique to assess the iterative outcome of single colonies. The ACO method can measure all subsets of satellites while reducing computer load by eliminating the need for a matrix inversion. Based on the simulation results, the GPS GDOP clustering technique is more efficient at achieving its optimum value.

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Tovar Soto, Jhonatan Paolo, Carlos Francisco Pareja Figueredo, Jonathan Steven Vargas Cañón, and Luis Carlos Gutiérrez Martínez. "A review of the current state of Pico and Nanosatellites: some applications in Latin America and other regions of the world." GRAINE. Boletín de Investigaciones. 2, no. 1 (September 1, 2020): 13–30. http://dx.doi.org/10.52408/vol2iss1pp13-30.

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Small satellites have been a fundamental factor in the constant growth of space technologies from 60 years ago. Since the space war began during the Cold War, thousands of satellites have been put into low orbit to carry out radio frequency applications, analysis and sending satellite images of the earth, joint research tasks for space exploration on artificial satellites, as well as missions in other astronomical bodies. By 2019, more than 50 countries around the world have put into orbit at least 1 small satellite, which accounts for the persistent work to increase the applications of these devices and the need make known the potential of these elements for research and for technological applications. Due to this, the present article was based on the documentary search to carry out a review of the current state of small satellites, and especially of nano and pico satellites. The research defined 3 phases for the writing of this document: choice of databases and search engines according to the research area, use of selection algorithms using logical discrimination chains and, finally, extensive analysis of the chosen documents for the writing of the article. All the information was presented through statistical graphs with detailed information from years of publication, language, region, terms, and areas the greatest research of small satellites. It was found that CubeSat and CanSat are the types of nano and pico satellite with the greatest predilection for research by universities and technological institutions, given its low cost and in most cases its easy implementation.

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Tovar Soto, Jhonatan Paolo, Carlos Francisco Pareja Figueredo, Jonathan Steven Vargas Cañón, and Luis Carlos Gutiérrez Martínez. "A review of the current state of Pico and Nanosatellites: some applications in Latin America and other regions of the world." GRAINE. Boletín de Investigaciones. 2, no. 1 (September 1, 2020): 13–30. http://dx.doi.org/10.52408/gbdivol2iss1pp13-30.

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Small satellites have been a fundamental factor in the constant growth of space technologies from 60 years ago. Since the space war began during the Cold War, thousands of satellites have been put into low orbit to carry out radio frequency applications, analysis and sending satellite images of the earth, joint research tasks for space exploration on artificial satellites, as well as missions in other astronomical bodies. By 2019, more than 50 countries around the world have put into orbit at least 1 small satellite, which accounts for the persistent work to increase the applications of these devices and the need make known the potential of these elements for research and for technological applications. Due to this, the present article was based on the documentary search to carry out a review of the current state of small satellites, and especially of nano and pico satellites. The research defined 3 phases for the writing of this document: choice of databases and search engines according to the research area, use of selection algorithms using logical discrimination chains and, finally, extensive analysis of the chosen documents for the writing of the article. All the information was presented through statistical graphs with detailed information from years of publication, language, region, terms, and areas the greatest research of small satellites. It was found that CubeSat and CanSat are the types of nano and pico satellite with the greatest predilection for research by universities and technological institutions, given its low cost and in most cases its easy implementation.

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Seo, Jae Young, and Sang-Il Lee. "Fusion of Multi-Satellite Data and Artificial Neural Network for Predicting Total Discharge." Remote Sensing 12, no. 14 (July 13, 2020): 2248. http://dx.doi.org/10.3390/rs12142248.

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As research on the use of satellites in combination with previous hydrological monitoring techniques increases, interest in the application of the machine-learning approach to the prediction of hydrological variables is growing. Ground-based measurements are often limited due to the difficulties in measuring spatiotemporal variations, especially in ungauged areas. In addition, there are no existing satellites capable of measuring total discharge directly. In this study, Artificial neural network (ANN) machine-learning approaches are examined for the prediction of 0.25° total discharge data over the Korean Peninsula using the data fusion of multi-satellites, reanalysis data, and ground-based observations. Terrestrial water storage changes (TWSC) of the Gravity Recovery and Climate Experiment (GRACE) satellite, precipitation of the tropical rainfall measuring mission (TRMM), and soil moisture storage and average temperature of the global land data assimilation system (GLDAS) models are used as ANN model input data. The results demonstrate the relatively good performance of the ANN approach for predicting the total discharge in terms of the correlation coefficient (r = 0.65–0.95), maximum absolute error (MAE = 13.28–20.35 mm/month), root mean square error (RMSE = 22.56–34.77 mm/month), and Nash-Sutcliff efficiency (NSE = 0.42–0.90). The precipitation is identified as the most influential input parameter through a sensitivity analysis. Overall, the ANN-predicted total discharge shows similar spatial patterns to those from other methods, while GLDAS underestimates the total discharge with a smaller dynamic range than the other models. Thus, the potential of the ANN approach described herein shows promise for predicting the total discharge based on the data fusion of multi-satellites, reanalysis data, and ground-based observations.

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Ahmed K. Izzet. "Solar Radiation Pressure Effects on the Orbital Elements of Artificial Earth Satellite." Tikrit Journal of Pure Science 20, no. 4 (February 10, 2023): 73–82. http://dx.doi.org/10.25130/tjps.v20i4.1216.

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The solar radiation pressure is one of the non-conservative force perturbation effects on earth satellite. A method presented to calculate the effect of radiation pressure on orbital elements for different altitude of satellites, the necessary calculation down by using modern Mat lab computer language. Typical results presented for radiation effect at deferent values of area mass ratio(A/m), the computed results indicated that the orbital elements much affected by solar radiation at high value of area mass ratio, also the effect on high orbit satellite is much more than that on low orbit satellite. The study also include the solar radiation pressure at two different value of ascending node ( Ω = 00 and Ω = 1800 ).

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Lawler, Samantha M., Aaron C. Boley, and Hanno Rein. "Visibility Predictions for Near-future Satellite Megaconstellations: Latitudes near 50° Will Experience the Worst Light Pollution." Astronomical Journal 163, no. 1 (December 17, 2021): 21. http://dx.doi.org/10.3847/1538-3881/ac341b.

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Abstract Megaconstellations of thousands to tens of thousands of artificial satellites (satcons) are rapidly being developed and launched. These satcons will have negative consequences for observational astronomy research, and are poised to drastically interfere with naked-eye stargazing worldwide should mitigation efforts be unsuccessful. Here we provide predictions for the optical brightnesses and on-sky distributions of several satcons, including Starlink, OneWeb, Kuiper, and StarNet/GW, for a total of 65,000 satellites on their filed or predicted orbits. We develop a simple model of satellite reflectivity, which is calibrated using published Starlink observations. We use this model to estimate the visible magnitudes and on-sky distributions for these satellites as seen from different places on Earth, in different seasons, and different times of night. For latitudes near 50° north and south, satcon satellites make up a few percent of all visible point sources all night long near the summer solstice, as well as near sunrise and sunset on the equinoxes. Altering the satellites’ altitudes only changes the specific impacts of the problem. Without drastic reduction of the reflectivities, or significantly fewer total satellites in orbit, satcons will greatly change the night sky worldwide.

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Sybiryakova, Ye S., O. V. Shulga, V. S. Vovk, M. P. Kaliuzhniy, F. I. Bushuev, M. O. Kulichenko, M. I. Haloley, and V. M. Chernozub. "The Artificial Satellites’ Observation Using the Complex of Telescopes of RI «MAO»." Science and innovation 13, no. 1 (April 12, 2017): 10–14. http://dx.doi.org/10.15407/scine13.01.010.

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Guan, Yue, Xiang Zhang, Danhe Chen, and Shuhui Fan. "Artificial potential field-based method for multi-spacecraft loose formation control." Journal of Physics: Conference Series 2746, no. 1 (May 1, 2024): 012053. http://dx.doi.org/10.1088/1742-6596/2746/1/012053.

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Abstract This study presents a control strategy based on artificial potential fields to maintain loose formation flying of satellites without a fixed formation, ensuring collision avoidance and stability under various conditions. The approach employs artificial potential fields for obstacle evasion and maintaining relative distances between satellites. Comprehensive simulations validate this method, with Monte Carlo techniques confirming control stability despite variations in initial conditions. The strategy effectively manages the integration of external satellites, maintaining optimal formation even as operational demands increase.

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Almalki, Faris A., and Soufiene Ben Othman. "Predicting Joint Effects on CubeSats to Enhance Internet of Things in GCC Region Using Artificial Neural Network." Mobile Information Systems 2021 (November 25, 2021): 1–16. http://dx.doi.org/10.1155/2021/1827155.

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Satellite telecommunication systems promise to bridge digital gaps and deliver wireless communication services to any corner of the world. However, despite satellites’ global connectivity and wide footprint, still atmospheric and dust impairments are open challenges that face satellite systems, especially at high-frequency bands in arid and semiarid regions. Therefore, this paper aims to predict joint effects of atmospheric and dust attenuations in Gulf Cooperation Council (GCC) countries on CubeSat communications using Artificial Neural Network (ANN). The prediction model has been carried out using a massive Multiple-Input Multiple-Output (MIMO) antenna payload at K-frequency Bands. Consider these joint effects have positive relations in calculating satellites link margin, which leads to obtaining efficient communication system, delivering better quality of service (QoS), and enhancing Internet of Things (IoT) connectivity, or even Internet of Space Things (IoST). Predicated results infer that the ANN attenuation predictions, along with the 5G MIMO antenna on-board the CubeSat, offer much promise channel model for satellite communications, which in turn leads to not only supporting IoT connectivity but also reducing power consumption, thus enhancing lifetime of CubeSat. Also, this study can provide a reference for CubeSat engineers to guarantee large-capacity communication.

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CARVALHO, J. P. S., D. C. MOURÃO, A. ELIPE, R. VILHENA DE MORAES, and A. F. B. A. PRADO. "FROZEN ORBITS AROUND EUROPA." International Journal of Bifurcation and Chaos 22, no. 10 (October 2012): 1250240. http://dx.doi.org/10.1142/s0218127412502409.

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Low-altitude, near-polar orbits are very desirable for scientific missions to study the natural satellites of the planets of the Solar System, such as Europa, that is one of the natural satellites of Jupiter. The problem is analyzed considering that an artificial satellite is orbiting Europa and that this spacecraft is perturbed by the nonuniform distribution of mass of the planetary satellite (J2, J3, C22) and by the gravitational attraction of the third-body. We present an analytical theory using the averaged model and applications were done by performing numerical integrations of the analytical equations developed. Using the averaged method, several frozen orbits were obtained. Some of them has low inclination, low altitude and long lifetime. Numerical simulations are performed using the software Mercury, to compare the results obtained using the analytical theory.

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Khalil, Khalil I., and Mohamed N. S. Ismail. "Effects of radiation pressure and earth’s oblatness on high altitude artificial satellite orbit." Astronomy Studies Development 1, no. 1 (March 18, 2011): e2. http://dx.doi.org/10.4081/708.

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This paper is devoted to study the effects of radiation pressure together with tesseral and zonal harmonics on the high altitude artificial satellites orbits. The equations of motion were regularized by using the KS variables and the problem was solved numerically using the fourth order of Runge Kutta method. A numerical testing was performed on Lageos-1 satellite in order to analyze its orbital changes due to effects of both radiation pressure and Earth's oblateness.

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Journal articles on the topic 'Artificial satellites'

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