Application Research and Design of XFDU on Definition of Telemetry Data

Design of fixed data format on spacecraft can cause problems such as data redundancy, unnecessary data occupying downlink bandwidth, and transferring undesired or useless data. In order to solve these problems, a data format encapsulation method which adopting CCSDS XFDU standard referencing to XFDU design method in OAIS model, and a data definition model based on parameter definition method in PUS are proposed. Corresponding designs including metadata XML schema of data definition model, metadata code table and XFDU format file are given. Then a XFDU converter was designed and tested, to support transforming binary data strings which descript data format into XML file, to generate metadata text according to metadata XML schema. A universal XFDU converter can be used in different systems to recognize and explain data format, to support heterogeneous information understanding among heterogeneous systems. Using XFDU can make the telemetry data definition model connecting to OAIS model, and will be in favor of data transferring, processing and preservation. This flexible data definition method will be a way of satellite definition.