Introduction to polar earth orbits (PEO) in the function of the satellite distress and safety systems (SDSS)

<p align="LEFT">In this paper is described introduction of Polar Earth Orbits (PEO) in the function of the Satellite Distress and Safety Systems (SDSS) for all mobile applications. The results of a technical and economic study regarding the extension of the Inmarsat Geostationary Earth Orbit (GEO) satellite system to cover polar region are reviewed. In addition, also are examined the technical and practical aspects of providing an operational polar Mobile Satellite Service (MSS) for the provision of combined distress and safety communication solutions in conjunction with a commercial and defense communication systems for maritime, land and aeronautical applications. This study is considered several PEO satellite models and their probable costs for Search and Rescue (SAR) and determination MSS solutions. The practical usage of Low PEO constellation is realized by Cospas-Sarsat international project for SDSS.</p>

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THE USE OF NEAR-EARTH ORBITS BY SATELLITE SYSTEMS IN DIFFERENT FREQUENCY BANDS

Труды НИИР ◽

10.34832/niir.2021.4.1.005 ◽

2021 ◽

Author(s):

Н.В. ВАРЛАМОВ ◽

С.С. УВАРОВ

Keyword(s):

Communication Systems ◽

Satellite Communication ◽

Geostationary Orbit ◽

Frequency Bands ◽

Satellite Systems ◽

Elliptical Orbits ◽

Earth Orbits ◽

Satellite Service

Выполнен анализ интенсивности использования геостационарной орбиты (ГСО) и негеостационарных орбит (НГСО) современными системами спутниковой связи фиксированной спутниковой службы в Ки-, Ка- и Q/V-диапазонах частот. Исследование охватывает ГСО, а также два наиболее используемых сегмента НГСО с высотой апогея до 1500 км и выше 8000 км. Представлены также результаты исследований для высокоэллиптических орбит (ВЭО). Сделан вывод о дефиците орбитально-частотного ресурса на ГСО и НГСО для рассматриваемых диапазонов частот. The paper analyzes the intensity of the use of geostationary orbit (GSO) and non-geostationary orbits (non-GSO) by modern satellite communication systems of the fixed-satellite service in the Ku-, Ka- and Q/V-bands. The analysis is made for geostationary orbit and two most used segments of non-GSO orbits with apogee altitudes up to 1500 km and above 8000 km. Results for highly inclined elliptical orbits (HEO) are also presented. The analysis results show a shortage of orbital and frequency resources in GSOs and non-GSOs for the considered frequency bands.

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Propagation Delay Difference Estimation for Initial Random Access in LTE Compatible Mobile Satellite Communications System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.846-847.647 ◽

2013 ◽

Vol 846-847 ◽

pp. 647-650

Author(s):

Cheng Mei Li ◽

Jian Jun Wu ◽

Xiao Ning Zhang ◽

Xi Luan ◽

Hai Ge Xing

Keyword(s):

Estimation Method ◽

Random Access ◽

Satellite Communications ◽

Propagation Delay ◽

Satellite System ◽

Satellite Systems ◽

Access Channel ◽

Geo Satellite ◽

Mobile Satellite ◽

Delay Difference

In this paper, a two-step propagation delay difference estimation method is proposed for LTE compatible multi-beam satellite systems to ensure the initial random access (RA). For GEO satellite system, there exists a large propagation delay difference, we cannot directly apply the LTE delay estimation method. To deal with this issue, we first divide a satellite beam into some layered small sub-areas according to the different delay difference values. Then, two types of Physical Random Access Channel (PRACH) preamble burst format are given. The detailed PRACH parameters are provided. Finally, simulations are performed and the results verify the availability of our proposed design.

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Preliminary Analysis and Evaluation of BDS-3 RDSS Timing Performance

Remote Sensing ◽

10.3390/rs14020352 ◽

2022 ◽

Vol 14 (2) ◽

pp. 352

Author(s):

Rui Guo ◽

Dongxia Wang ◽

Nan Xing ◽

Zhijun Liu ◽

Tianqiao Zhang ◽

...

Keyword(s):

Evaluation Method ◽

Satellite System ◽

Timing Accuracy ◽

Analysis And Evaluation ◽

Geo Satellite ◽

The One ◽

Satellite Service ◽

First Time ◽

Performance Timing ◽

Better Than

Radio determination satellite service (RDSS) is one of the characteristic services of Beidou navigation satellite system (BDS), and also distinguishes with other GNSS systems. BDS-3 RDSS adopts new signals, which is compatible with BDS-2 RDSS signals in order to guarantee the services of old users. Moreover, the new signals also separate civil signals and military signals which are modulated on different carriers to improve their isolation and RDSS service performance. Timing is an important part of RDSS service, which has been widely used in the field of the power, transportation, marine and others. Therefore, the timing accuracy, availability and continuity is an important guarantee for RDSS service. This paper summarizes the principle of one-way and two-way timing, and provides the evaluation method of RDSS timing accuracy, availability and continuity. Based on BDS-3 RDSS signal measurements of system, the performance of one-way timing and two-way timing is analyzed and evaluated for the first time. The results show that: (1) the accuracy of one-way timing and two-way timing is better than 30 ns and 8 ns respectively, which are better than the official claimed accuracy; (2) the RMS of one-way timing accuracy is 5.45 ns, which is 20% smaller than BDS-2, and the availability and continuity are 100%; (3) the RMS of two-way timing accuracy is 3.59 ns, which is 34% smaller than one-way timing, and both of the availability and continuity are 100%; (4) the orbit maneuver of GEO satellite make the one-way timing has 7.68 h recovery, but has no affection on the two-way timing.

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SATCOM/ADS: The Key to CNS Integration for ATM in Europe?

Journal of Navigation ◽

10.1017/s037346330001287x ◽

1995 ◽

Vol 48 (3) ◽

pp. 361-373

Author(s):

M. E. Cox

Keyword(s):

Traffic Management ◽

Low Cost ◽

Air Traffic Management ◽

Satellite System ◽

Civil Aviation ◽

Navigation Satellite ◽

Potential Benefits ◽

Mobile Satellite ◽

Global Navigation Satellite ◽

Satellite Service

The availability of an aeronautical mobile satellite service and the emergence of a global navigation satellite system should enable CNS services to be established for civil aviation, virtually worldwide. This paper discusses how the development of a low-cost ADS system, employing these satellite services, might be used to the advantage of European air traffic management (ATM). It indicates that the earlier action is taken, the greater will be the potential benefits. This paper is an updated version of that presented at the NAV94 Conference in November 1994.

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