ISO 20208:2015

Overview

ISO 20208:2015 - Space data and information transfer systems - Delta‑DOR Raw Data Exchange Format (RDEF) - specifies a standardized file format for exchanging Delta‑DOR (Delta Differential One‑Way Ranging) raw data among space agencies. Originating from the CCSDS Recommended Standard (CCSDS 506.1‑B‑1), ISO 20208:2015 defines the structure and parameter fields required to support inter‑agency correlation and processing of Very Long Baseline Interferometry (VLBI) Delta‑DOR observations used to improve spacecraft angular positioning.

Key topics and technical requirements

• Scope and purpose: Standardizes raw Delta‑DOR data format for inter‑agency exchange when correlation involves at least one station outside the responsible agency. Suitable for open‑loop raw data collection as well.
• File structure: Defines Observation files and Product files, including header, scan, product, and ending sections. (See clause and figure listings for file layout.)
• Parameter fields: Specifies the parameter fields and conventions the format must support; includes conventions for identifiers and file naming.
• Automation focus: Designed primarily for computer‑to‑computer automated exchanges and processing workflows.
• Data characteristics: Records sampling rate and quantization in the RDEF; no accuracy specification for raw Delta‑DOR data (accuracy assessment of reduced measurements is out of scope).
• Transmission out of scope: The standard defines content and format but does not mandate transmission methods - agencies may use CCSDS transfer protocols, SFTP, stream media, or other secure channels.
• Normative and informative annexes: Includes annexes covering normative parameter conventions and informative topics such as security, SANA, patent considerations, abbreviations, and examples.

Applications and users

• Primary use: Exchange of Delta‑DOR raw data for joint VLBI correlation and spacecraft navigation campaigns to improve angular position (plane‑of‑sky) estimates.
• Typical users:
  • Space agencies and mission operations centers coordinating multi‑agency tracking
  • Ground segment engineers developing data ingest and correlation systems
  • Navigation teams integrating Delta‑DOR with Doppler and ranging data
  • Software developers implementing automated file‑based ingestion and processing pipelines
• Practical value: Enables consistent, interoperable raw data interchange across agencies, reduces integration errors, and supports multi‑station correlation workflows critical to deep‑space navigation.

Related standards

• CCSDS family standards on space data systems (CCSDS 506.1‑B‑1 is the originating Recommended Standard adopted as ISO 20208:2015).
• Complementary CCSDS file transfer and data‑transfer protocol standards for secure transport (transmission mechanisms are chosen by participating agencies).

Keywords: ISO 20208:2015, Delta‑DOR, RDEF, VLBI, raw data exchange format, spacecraft navigation, inter‑agency data exchange, CCSDS.