适用于我国天基网络的GEO/LEO双层星座的设计与仿真分析

Design and simulation analysis of a double-layered GEO/LEO satellite constellation for China's future space-based networks

为避免同步地球轨道(GEO)卫星网络的传播时延大、实时业务传输保障能力有限的问题,研究了双层卫星网络的设计。考虑到GEO卫星相对地面位置固定,低地球链道(LEO)卫星功率损耗较低,传输时延较短,根据我国地理位置及未来天基网络建设需要,设计了一种简捷高效的GEO/LEO双层卫星星座网络结构。该结构按"弱连接"理论,使LEO卫星与通信质量最优的一颗GEO卫星建立链路,以保证通信质量的最优化;采用"骨干/接入"模型,使GED层卫星构成骨干网,LEO层卫星构成接入网,以克服设计的高难度。仿真结果表明,GEO/LEO双层卫星网络在覆盖特性和星际链路几何特性上更具优势,满足我国未来天基网络建设要求。

To avoid geosynchronous earth orbit （GEO） satellite networks＇ problems of long transmission delay and weak ability in real-time traffic transfering, the design of double-layered satellite networks was studied. Considering that GEO satellites＇ position relative to the ground is fixed, and low earth orbit （LEO） satellites have the advantages of lower power loss and shorter transmission delay, a simple and efficient double-layered GEO/LEO satellite network was designed according to China＇ s geographical position and demands of future space-based network construction. The design follows the weekness connection theory to make the LEO satellite establish the link with a GEO satellite with the optimum communication quality to guarantee the best communication of the system, and obeys the back- bone/access model to make the GEO layer construct the backbone network while the LEO layer construct the access network to overcome the high design difficulty. The simulation results show that the double-layered GEO/LEO sat- ellite network has more advantages in coverage characteristics and the inter satellite link （ISL） geometric character- istics, meeting the reqirements of China＇ s future space-based network construction.