共查询到20条相似文献,搜索用时 31 毫秒
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The Combined-GEO-IGSO constellation is the combination of Geostationary Earth Orbit (GEO) satellite and Inclining GeoSynchronous
Orbit (IGSO) satellite. The Combined-GEO-IGSO constellation can integrate the advantages of GEO and IGSO to achieve regional
coverage. In order to discuss the performances of the Combined-GEO-IGSO constellation, the performances of coverage, elevation,
diversity, and transmission are simulated in China and surrounding regions by Satellite Tool Kit (STK). The simulation results
show that: the combined constellation can reach higher multi-satellite coverage and higher communication elevation in China
and surrounding areas; the Doppler shift, delay, and propagation loss of this constellation have little impact on the system.
As regional coverage constellation, the Combined-GEO-IGSO is feasible. 相似文献
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Positioning accuracy of the Global Navigation Satellite System (GNSS) can be analyzed by Positioning Dilution Of Precision (PDOP).In order to enhance the navigating performance of Asia and the Pacific areas,this paper analyzes the next generation BeidouTM navigation satellite system (CompassTM) enhanced by Geostationary Earth Orbit (GEO) and Inclining GeoSynchronized Orbit (IGSO).As global navigation satellite system,CompassTM must be robust enough to avoid system layoff,when some nodes are not available.So,the CompassTM enhanced by GEO and IGSO constellation is proposed and analyzed its PDOP proformance,this paper shows some exciting results of performance of CompassTM enhanced by GEO and IGSO.From the simulation results,we can found that:when more than fifteen satellites are invalid,the enhanced system could be operating normally. 相似文献
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Positioning accuracy of the Global Navigation Satellite System (GNSS) can be analyzed by Positioning Dilution Of Precision
(PDOP). In order to enhance the navigating performance of Asia and the Pacific areas, this paper analyzes the next generation
Beidou™ navigation satellite system (Compass™) enhanced by Geostationary Earth Orbit (GEO) and Inclining GeoSynchronized Orbit
(IGSO). As global navigation satellite system, Compass™ must be robust enough to avoid system layoff, when some nodes are
not available. So, the Compass™ enhanced by GEO and IGSO constellation is proposed and analyzed its PDOP proformance, this
paper shows some exciting results of performance of Compass™ enhanced by GEO and IGSO. From the simulation results, we can
found that: when more than fifteen satellites are invalid, the enhanced system could be operating normally. 相似文献
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Tarik Taleb Abbas Jamalipour Nei Kato Yoshiaki Nemoto 《International Journal of Satellite Communications and Networking》2006,24(3):215-227
To meet an ever‐growing demand for wideband multimedia services and electronic connectivity across the world, development of ubiquitous broadband multimedia systems is gaining a tremendous interest at both commercial and academic levels. Satellite networks will play an indispensable role in the deployment of such systems. A significant number of satellite communication constellations have been thus proposed using Geostationary (GEO), Medium Earth Orbit (MEO), or Low Earth Orbit (LEO) satellites. These constellations, however, either require a potential number of satellites or are unable to provide data transmission with high elevation angles. This paper proposes a new satellite constellation composed of Quasi‐GeoStationary Orbit (Quasi‐GSO) satellites. The main advantage of the constellation is in its ability to provide global coverage with a significantly small number of satellites while, at the same time, maintaining high elevation angles. Based on a combination of this Quasi‐GSO satellites constellation and terrestrial networks, the paper proposes also an architecture for building a global, large‐scale, and efficient Video‐on‐Demand (VoD) system. The entire architecture is referred to as a ‘Theatre in the Sky’. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Satellite system architectures based on geostationary or Low Earth Orbit (LEO)/Medium Earth Orbit (MEO) constellation suffer from their intrinsic limitations in terms of coverage or flexibility. Traffic requirements concerning broadband services are expected to be very uneven both in time and space. To match this requirement and to improve coverage an innovative satellite system architecture, composed of a LEO/MEO segment to complement a Geostationary Earth Orbit (GEO) segment, has been proposed. In this scenario, to achieve interworking and to make it possible to hold the call while switching between the two segments, efficient intersegment handover (ISHO) procedures must be identified. The paper, after introducing the classical ISHO schemes, aims at defining and analysing an ISHO procedure developed to perform handover in case of hybrid constellations based on the use of both GEO and LEO/MEO orbits. Performance evaluation will be carried out for different system configurations utilizing a dynamic satellite constellation simulator in the time domain. The execution delay and its complementary cumulative distribution have been evaluated for different constellation geometry at different distances from the gateway. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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IRNSS(Indian Regional Navigation Satellite System)是印度独立开发的区域卫星导航系统, 由 3 颗 GEO(Geostationary Orbit)卫星和 4 颗 IGSO(Inclined Geo-synchronous Orbit)构成,目前已经发射 3 颗卫星,整个系统预计于 2015 年建成。IRNSS 建成之后将对南纬 30°至北纬 50°、东经 30°至东经 130°的区域提供准确的定位服务,集成 IRNSS 的多模卫星导航接收机将对上述区域的用户带来更好的服务。本文描述了 IRNSS 卫星星座、信号特点、调制方式,分析了 IRNSS 的 SPS 信号与其他卫星导航系统信号的差别,给出了在多模导航接收机芯片上集成 IRNSS 的方式。 相似文献
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该文讨论了使用中轨共地面轨迹星座建立区域覆盖卫星通信系统的优化设计方法。在深入研究共地面轨迹星座参数特性的基础上,提出了一种能够完整描述该类型星座的编码标识方法,推导了星座与星座的等价关系,讨论了利用该类型星座实现区域覆盖时的优化方法,给出了适用于我国的多个优化星座方案实例。从仿真结果可以看出,该类型星座能够以较少数量的卫星为我国提供良好的覆盖性能,适于我国的区域覆盖卫星通信系统采用。 相似文献
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卫星骨干网络将向宽带与中继融合方向发展,为陆、海、空、天基用户提供全球骨干传输、宽带接入、全域通联等服务。该文针对全域用户通联的新需求,创新采用“卫星骨干网络/全域用户接入”模型,提出一种具有层内、层间星间链路的中高轨混合的多层卫星骨干网络架构(3GEO+3IGSO/24MEO)。对该架构的全域覆盖性计算分析,得出该多层卫星骨干网络能够实现地球表面到地球同步轨道高度(约36000 km)全域100%覆盖,并为全域用户提供多重接入能力。进一步对路径数、最少跳数、最小时延等关键网络性能指标分析比较,说明了该架构中轨卫星与高轨卫星之间存在层间星间链路的必要性。分析结果表明:该架构能够满足全域宽带接入和全球骨干传输的需求。 相似文献
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导航卫星反射事件的空间分布和数量是星载反射信号应用的综合评估指标之一, 北斗系统作为我国独立研发的导航系统, 与其他系统相比, 其反射事件的空间分布和数量具有独特性.针对上述问题, 通过研究北斗系统空间星座的特征, 模拟生成了完整的北斗系统空间星座, 给出了反射事件空间分布和数量的分析步骤, 利用导航卫星反射信号的基本几何关系推导了镜面反射点存在性判决条件.从机理上分析了北斗反射事件的影响因素, 在此基础上仿真分析了低轨卫星轨道高度、倾角、升交点赤经以及近地点角距对北斗系统同步地球轨道、倾斜地球轨道和中地球轨道卫星反射事件空间分布和数量的影响.结果表明:低轨卫星高度、升交点赤经只影响北斗反射事件数量, 而不影响分布, 轨道倾角对数量和分布都有显著影响, 轨道近地点角距无显著影响.最后, 总结给出了对地观测需合理设计低轨卫星轨道参数的指导性结论.
相似文献
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Wei Zhou Yi‐fan Zhu Yao‐yu Li Qun Li Qin‐Zhang Yu 《International Journal of Satellite Communications and Networking》2020,38(2):162-176
In this paper, a three‐layered medium Earth orbit (MEO), geostationary Earth orbit (GEO), and inclined geosynchronous orbit (IGSO) satellite network (IGMSN) is presented. Based on the idea of time‐slot division, a novel dynamic hierarchical and distributed QoS (quality of service) routing protocol (HDRP) is investigated, and an adaptive bandwidth‐constrained minimum‐delay path for IGSO/GEO/MEO hierarchical architecture constellation (BMDP‐HAC) algorithm is developed to calculate routing tables efficiently using the QoS metric information composed of delays and bandwidth. The performance of the IGMSN and HDRP is evaluated through simulations and theoretical analysis. And then, the paper further analyzes the performance of the IGMSN structure and the BMDP‐HAC algorithm with failure satellites. 相似文献
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该文提出一种利用地球同步轨道(GEO)通信卫星信号转发实现卫星导航信号增强的方法。在信号发射端,利用卫星导航信号直接序列扩频(DSSS)的低功率信号特性,在满足一定通信信号误码率(BER)要求的前提下,将导航中心产生的功率受控弱卫星导航增强信号在所选GEO卫星通信频段上进行载波调制与转发。而在接收端,利用频移(FRESH)滤波器以及一定的自适应信号抵消算法,可有效去除强通信信号的干扰并分离出弱卫星导航增强信号。仿真结果表明,对于分离出的弱卫星导航增强信号,在其对应的功率控制范围内可具有较好的跟踪与捕获性能,由此也验证了所提方法的有效性。 相似文献
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低轨(LEO)宽带星座卫星通信作为地面5G无线通信系统的重要补充,始终面临地面可视卫星数量大、传统选星算法计算复杂度高等难题。为实现高效的卫星分组选择算法,基于多输入多输出(MIMO)系统原理,以大尺度路径损耗模型为基础,结合递减卫星选择算法,从而以较低计算复杂度、更快收敛速度有效逼近最优容量性能。该算法在典型LEO星座系统构型下通过数值仿真得到了验证,为未来5G低轨卫星星座通信传输方案设计提供了一种参考思路。 相似文献
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The architecture of cislunar multi-hop communication networks, which focuses on the re-quirements of lunar full-coverage and continuous cislunar communications, is presented on the basis of Geosynchronous Orbit (GEO) satellite network relays. According to the geographical distribution of the forthcoming Chinese Deep Space Measuring and Controlling Network (DSMCN ), two networking schemes are proposed and two elevation angle opti-mization models are established for locating GEO relay satellites. To analyze the dynamic connectivi-ty, a dynamic network model is constructed with re-spect to the time-varying characteristics of cislunar trunk links. The advantages of the two proposed schemes, in terms of the Connectivity Rate (CR), In-terruption Frequency (IF), and Average Length of Connecting Duration (ALCD), are corroborated by several simulations. In the case of the lunar polar orbit constellation case, the gains in the perform-ance of scheme I are observed to be 134.55% , 117. 03% , and 217. 47% compared with DSMCN for three evaluation indicators, and the gains in the per-formance of scheme II are observed to be 238.22% , 240.40% , and 572.71% . The results validate that the connectivity of GEO satellites outperforms that of earth facilities significantly and schemes based on GEO satellite relays are promising options for cislu-nar multi-hop communication networking. 相似文献
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LEO/MEO双层卫星网络层间星际链路建立策略的性能研究 总被引:1,自引:0,他引:1
从改善LEO/MEO双层卫星网络拓扑结构稳定性的角度出发,该文提出了3种基于集中重建的层间星际链路建立策略。新策略的基本思想是通过强制所有层间星际链路在相同时间进行重建来大幅减少网络拓扑的重构次数。仿真结果表明,与原有的策略相比,该文提出的策略能够以可接受的代价提高LEO/MEO双层卫星网络拓扑结构的稳定性。 相似文献