采用卫星中继克服航天器再入通信黑障的途径

On Approaches to Overcome Spacecraft Reentry Communication Blackout Using Satellite Relay

在简述载人航天器再入过程、等离子鞘套特点和中继传输原理的基础上,分析了采用卫星中继克服再入通信黑障的具体途径。考虑到必须采用较高工作频率(Ka频段)的一次中继方法存在一定局限性,提出了一种采用二次中继的新方法,它可以将再入通信的工作频率向低扩展到多数载人航天器在轨常用的S频段。文章讨论了这两种方法的优缺点,论述了实施它们对中继站和再入航天器的主要要求,并就影响其效果和航天器设计的重要因素进行了分析。链路计算结果表明:两种方法都可满足传输需求,从总体上考虑二次中继方法更好一些。考虑到我国空间基础设施和相关技术背景条件,在近期内卫星中继将是解决再入通信黑障问题可实现的技术途径。

On the basis of a brief describing manned spacecraft reentry course, characteristics of plasma sheath and relay transfer principles, specific approaches using satellite relay to overcome reentry communication blackout are analyzed. As the ＂one relay＂ approach which has to work at Ka band has some limitations in implementation, a new ＂two relays＂ approach is proposed. This approach can work at lower S band frequency used for current manned spaceerafts in orbit fre- quently. Their pros and cons are discussed. The main requirements to apply these approaches for relay and reentry spacecraft are described, and different factors influencing effects of these approa- ches and spacecraft design are analyzed. The link budget examples show that both approaches can meet mission requirements, but the ＂two relays＂ approach would be a better solution from system point of view. With considering Chinese space infrastructure and technologic background, the relay transfer would be the near-time technical solution to reentry blackout problem.