GB/T 39355-2020 in English
VALIDSpace data and information transfer systems—Time code formats
- Issued on:2020-11-19
- Implemented on:2021-06-01
- File Format:PDF
- Delivery:Via email within 1~3 business days
$214.00
《GB/T 39355-2020空间数据与信息传输系统 时间码格式》由TC425（全国宇航技术及其应用标准化技术委员会）归口，TC425SC3（全国宇航技术及其应用标准化技术委员会空间数据与信息传输分会）执行，主管部门为国家标准化管理委员会。
Introduction
Analysis of the core content of the standard
| Time code type | Time resolution | Epoch basis | Leap second processing | Typical application |
|---|---|---|---|---|
| Non-segmented time code | Up to 80-bit sub-second part | 1958-01-01(TA) | Not processed | Deep space mission |
| Day segmented time code | 16/24-bit day segment + sub-millisecond segment | Customizable | Correction required | Near Earth Satellite |
| Calendar Segment Time Code | 1×10-12s | UTC System | Correction required | Ground Measurement and Control |
Key Technical Differences
Compared with ISO11104:2011, the main adjustments of this standard include: deletion of CCSDS classification description, addition of GB/T2900.54 reference, and restructuring of appendix structure. The technical differences are reflected in the P domain extension mechanism (b0 bit control) and the ASCII code subset truncation rules.
Implementation Suggestions
1. Deep space exploration missions recommend the use of non-segmented time codes (identifier bit 001). The combination of 56-bit seconds + 80-bit sub-seconds can meet the continuous timing requirements for up to 292 years
2. Ground systems that require UTC synchronization should choose a segmented calendar format and pay attention to the leap second flag processing rules: when the second value is 60, it indicates a positive leap second, and 59→60 is an invalid state
Evolution Analysis
The standard introduces the complete truncation rules of the ASCII code calendar format for the first time, supporting flexible combinations from "YYYY-MM-DDThh:mm:ss" to "mm:ss" to adapt to different bandwidth scenarios. The custom time code realizes the T domain expansion capability of 1-16 bytes through the P domain b4~b7 bits.
Loading PDF document...
Error loading PDF. Please make sure the file is valid and try again.
We also recommend
-
GB/T 46525-2025 in English
Space data and information transfer systems—Spacecraft information system service and protocol architecture
2025-10-31 -
GB/T 42038-2022 in English
Space data and information transfer systems—File delivery protocol
2022-10-12
