基于时延和多普勒频移的海事卫星机载终端定位技术--如何利用海事卫星定位搜索失联飞机

摘要

在海事卫星通信中，地球关口站和用户移动终端的载波信号会受到传输距离和多普勒频移等因素的影响。为了提升海事卫星射频通信系统接收性能和频带资源利用，海事卫星通信系统中采用根据用户移动终端地理位置进行自动频率补偿和时延补偿的技术，同时地面系统还实时记录了时延和多普勒频移的相关参数，为逆向分析用户移动终端位置提供了可能。介绍海事卫星通信系统中时延和频移的补偿方法，进一步研究基于时延和多普勒频移的海事卫星机载终端定位技术。技术对提升特殊情况下的定位和搜救能力有重要意义，而较好地掌握这门技术还可以促进相关卫星通信系统的研发。%The signal between the GES ( Ground Earth Station ) and AES ( Aircraft Earth Station ) is affected by the transmis-sion distance and Doppler effect .To improve the spectrum utilization and the performance of radio communication , the automatic frequency control and time delay compensation based on the location of AES are widely used in the Inmarsat system .The GES re-cords all data associated with the time delay and Doppler frequency , which makes it possible to analyze the location of AES .The pa-per introduces the compensation methods of time delay and frequency in the Inmarsat system , and takes a further research on the po-sitioning technology of AES based on the time delay and Doppler effect .This paper has great significance for the AES positioning in special circumstances and the maritime rescue capability improvement , and the positioning technology has some active effect on the development of other mobile satellite systems .