北斗系统的建设实践,实现了在区域快速形成服务能力、逐步扩展为全球服务的发展路径,丰富了世界卫星导航事业的发展模式。
The BDS development follows a model of developing regional service capacities, then gradually extending the service globally. This practice has enriched the development models for navigation satellite systems worldwide.
北斗系统具有以下特点:一是北斗系统空间段采用三种轨道卫星组成的混合星座,与其他卫星导航系统相比高轨卫星更多,抗遮挡能力强,尤其低纬度地区性能特点更为明显。二是北斗系统提供多个频点的导航信号,能够通过多频信号组合使用等方式提高服务精度。三是北斗系统创新融合了导航与通信能力,具有实时导航、快速定位、精确授时、位置报告和短报文通信服务五大功能。
The BDS possesses the following characteristics: First, its space segment is a hybrid constellation consisting of satellites in three kinds of orbits. In comparison with other navigation satellite systems, the BDS operates more satellites in high orbits to offer better anti-shielding capabilities, which is particularly observable in terms of performance in the low-latitude areas. Second, the BDS provides navigation signals of multiple frequencies, and is able to improve service accuracy by using combined multi-frequency signals. Third, the BDS integrates navigation and communication capabilities for the first time, and has five major functions - real-time navigation, rapid positioning, precise timing, location reporting and short message communication services.
为满足日益增长的用户需求,北斗系统将加强卫星、原子钟、信号体制等方面的技术研发,探索发展新一代导航定位授时技术,持续提升服务性能。
To meet the increasing user demand, BDS technical research and development in the areas of satellites, atomic clocks and signals will be strengthened, and a new generation of navigation, positioning and timing technologies will be explored to improve service performance.
——提供全球服务。发射新一代导航卫星,研制更高性能的星载原子钟,进一步提高卫星性能与寿命,构建稳定可靠的星间链路;增发更多的导航信号,加强与其他卫星导航系统的兼容与互操作,为全球用户提供更好的服务。
– Providing global services. China will launch new-generation navigation satellites, develop airborne atomic clocks with enhanced performance, further improve the performance and lifetime of satellites, and build more stable and reliable inter-satellite links. It will broadcast additional navigation signals, and enhance the compatibility and interoperability with other navigation satellite systems, so as to provide better services for global users.
——增强服务能力。大力建设地面试验验证系统,实现星地设备全覆盖测试验证;持续建设完善星基和地基增强系统,大幅提高系统服务精度和可靠性;优化位置报告及短报文通信技术体制,扩大用户容量,拓展服务区域。
– Strengthening service capabilities. China will establish a grounded test and validation bed to accomplish the full coverage of tests and validation for space and ground equipment; continue to build and improve satellite based and ground based augmentation systems to substantially enhance BDS service accuracy and reliability; optimize the technical system of location reporting and short message communication to expand user volume and service coverage.
——保持时空基准。北斗系统时间基准(北斗时),溯源于协调世界时,时差信息在导航电文中发播;推动与其他卫星导航系统开展时差监测,提高兼容与互操作。发展基于北斗系统的全球位置标识体系,推动北斗系统坐标框架与其他卫星导航系统的互操作,并不断精化参考框架。
– Maintaining spatio-temporal reference. The BDT is related to the Coordinated Universal Time, and the time bias information is broadcast in the navigation message. China will push forward the clock bias monitoring with other navigation satellite systems, and improve their compatibility and interoperability. It will develop a BDS-based worldwide location identification system, increase the interoperability between BDS coordinate frame and that of other navigation satellite systems, and constantly refine the reference frame.