CCSDS统一空间数据链路协议应用分析

针对TM、TC、AOS、Proximity-1四种空间数据链路协议的应用局限性，对CCSDS（国际空间数据系统咨询委员会）提出的统一空间数据链路协议（Unified Space Data Link Protocol， USLP）规范进行分析，介绍了USLP传输帧主导头和数据域中各个字段的设计驱动，以及与其他空间数据链路协议的差异。对于服务数据单元信道复用传输需求，梳理了物理信道、主信道、虚拟信道、多路复用访问信道的服务类型，明确了数据传输服务、信道复用、信道标识、服务数据单元之间的关联关系。以遥测遥控数据空间链路传输为例，分析了USLP的适用性和推荐设置。

Analysis on application of CCSDS unified space data link protocol

Aimed at the application limitations of TM, TC, AOS, Proximity-1 space data link protocol, this paper analyzes the unified space data link protocol specification standardized by CCSDS, and introduces the design drivers of USLP transfer frame primary header and data field, as well as the differences with other space data link protocol. This protocol enables service data units to be multiplexed together in one channel and provides service types for a physical channel, master channel, virtual channel, multiplexer access point channel. This paper shows logical relationships among data transfer service, channel multiplexing, channel identifier and service data unit. Transfer telemetry and command data over a space link , for instance, the applicability and recommended of USLP are analyzed.