COVERAGE PERFORMANCES ANALYSIS ON COMBINED-GEO-IGSO SATELLITE CONSTELLATION1

The Combined-GEO-IGSO constellation is the combination of Geostationary Earth Orbit (GEO) satellite and Inclining GeoSynchronons 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.     

GEO和IGSO卫星增强GPS性能的仿真分析

为了增强GPS在亚太地区的导航性能,提出了一种利用GEO和IGSO卫星增强GPS星座的方法。通过仿真分析,研究了该地区在星座增强前后的卫星可见性、PDOP值等方面的变化规律,通过对比导航系统在全球范围内的性能表现,证明这种增强系统在定位精度和可用性方面均有较大提高。     

基于北斗一代的区域导航星座的优化设计

分析北斗一代对我国及周边地区的覆盖特性,研究以现有北斗一代3颗GEO卫星为基础的IGSO区域导航星座的优化设计。通过对星下点轨迹的仿真分析,得出区域覆盖特性最优时IGSO星座的升交点赤经、近地点幅角、初始相位角应满足的条件。采用网格点仿真法,以区域覆盖特性和位置精度因子为优化指标,阐述IGSEO星座的偏心率和IGSCO星座的倾角的优化设计过程。给出2种基于北斗一代的区域导航星座方案,2种方案均可对我国及周边地区实现连续6重覆盖,且平均PDOP小于4。     

SIMULATION AND ANALYSIS OF PERFORMANCE ON THE COMPASSTM ENHANCED BY GEO AND IGSO

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.     

An improved group search optimizer with operation of quantum-behaved swarm and its application

Group search optimizer (GSO) is a novel swarm intelligent (SI) algorithm for continuous optimization problem. The framework of the algorithm is mainly based on the producer-scrounger (PS) model. Comparing with ant colony optimization (ACO) and particle swarm optimization (PSO) algorithms, GSO emphasizes more on imitating searching behavior of animals. In standard GSO algorithm, more than 80% individuals are chosen as scroungers, and the producer is the one and only destination of them. When the producer cannot found a better position than the old one in some successive iterations, the scroungers will almost move to the same place, the group might be trapped into local optima though a small quantity of rangers are used to improve the diversity of it. To improve the convergence performance of GSO, an improved GSO optimizer with quantum-behaved operator for scroungers according to a certain probability is presented in the paper. In the method, the scroungers are divided into two parts, the scroungers in the first part update their positions with the operators of QPSO, and the remainders keep searching for opportunities to join the resources found by the producer. The operators of QPSO are utilized to improve the diversity of population for GSO. The improved GSO algorithm (IGSO) is tested on several benchmark functions and applied to train single multiplicative neuron model. The results of the experiments indicate that IGSO is competitive to some other EAs.     

IGSO在卫星移动通信中的应用研究

研究利用IGSO星座提供卫星移动通信业务所涉及到的星座覆盖性能、多普勒频移及业务支持能力等问题。研究表明,采用2颗或3颗IGSO卫星构成的星座能够对我国区域提供较好的覆盖性能(单星和多星覆盖率及平均通信仰角),而引入的多普勒频移并不大。链路计算结果表明,采用IGSO卫星能够有效解决GEO卫星在高纬度区域的低仰角问题,并能用比较小的IGSO卫星来达到非常大的GEO卫星才能实现的性能。因此,采用IGSO的区域卫星移动通信系统具有较好的技术可行性。     

GEO卫星受IGSO卫星干扰情况分析研究

文章以倾斜地球同步轨道卫星(IGSO)地球站干扰对地静止轨道卫星(GEO)为研究对象,分析了IGSO卫星运行轨迹以及干扰信号出现的原理,最终得出规避干扰出现的建议或者措施,为卫星操作者提供技术参考。     

基于IGSO计及谐波电压畸变的无功优化

近年来电力电子装置的广泛应用引起了谐波污染。如果直接对电力系统进行无功优化,谐波频率下容易产生系统与电容器之间的谐振或谐波放大,使系统的谐波畸变率大为增加,破坏系统的安全运行。针对这一问题,提出了计及谐波电压畸变的无功优化模型;在网损最小的基础上,将各节点基波电压和总谐波畸变率越限情况以惩罚项的形式加入目标函数中,将改进萤火虫算法（IGSO）应用到无功优化中,给出基于IGSO计及谐波电压畸变的无功优化具体步骤。通过对IEEE 30节点算例的仿真分析,验证本方法的可行性和优越性,在减小网损和总谐波畸变率的同时,提高了收敛速度和计算精度。     

IGSO卫星75Ah锂离子蓄电池应用实践

75 Ah锂离子蓄电池作为IGSO卫星储能电池得到在轨应用,数据表明两组蓄电池在轨性能一致性高,单翼蓄电池组内22串电池的电压离散度小于20 m V,蓄电池温度梯度小于3.5℃,一个长光照期内,蓄电池荷电态保持在70%~80%,进行补充充电3次。蓄电池在轨实践表明蓄电池设计合理,性能稳定可靠,在轨管理方法合理有效。     

IGSO星座分析与优化设计

通过对典型IGSO星座摄动影响下星座构型分析，得到影响卫星轨道的主要摄动因素，并对IGSO星座进行长期演化分析，同时评价星座的稳定性。提出IGSO星座的优化设计方法：以一种双“8”字形、共轨道面的IGSO星座构型为例进行星座设计，设计变量包括卫星数目、轨道倾角、2个星座的交点地理经度，每个星座中第1颗卫星的相位角。采用多目标优化算法得到优化结果，以及星座的三维结构和星下点轨迹。分析结果表明方法合理有效，该星座构型具有较好性能。