Name of Group | 5.02 Space Link Coding and Synchronization Working Group |
Area | Space Link Services Area (SLS) |
Chairperson | Andrea Modenini |
Chairperson E-Mail Address | andrea.modenini@esa.int |
Chairperson Agency | ESA |
Deputy Chairperson | Kenneth Andrews |
Deputy Chairperson E-Mail Address | andrews@shannon.jpl.nasa.gov |
Deputy Chairperson Agency | NASA |
Mailing List | sls-cc@mailman.ccsds.org |
Scope of Activity | This working group will concentrate on creating, maintaining and updating the set of Channel Coding Books to incorporate recommended coding scheme for Telemetry, Telecommand and Proximity-1 links. |
Rationale for Activity | In order to establish a common framework within which the Agencies may develop standardized services for Telemetry, Telecommand and Proximity-1 links, the CCSDS advocates adoption of a layered systems architecture. Within this approach, the Coding and Synchronization Layer has the purpose of protecting higher layer data units (i.e. "frames") against errors induced during transmission through the physical path to/from a spacecraft. The Coding layer shall satisfy the System requirement for the error-free delivery of data units to the receiving end upper layer. It shall satisfy this task by encoding the user data from the layer above to protect them against noise-induced errors during transmission through the underlying radio frequency channel and by using suitable synchronization techniques to allow proper identification of the individual data units.. In addition the wide range of environment (space-Earth or space-space, near Earth congested bands and deep space link operations in extreme conditions of SNR, links dependent of atmospheric conditions in the new high frequency bands, optical links) requires coding systems with different levels of power efficiency and bandwidth efficiency, or different levels of link reliability or delivered data quality. Additionally, harsh environment impairments such as out-of-synchronization events, adverse weather conditions, and optical link turbulence demand for the application of higher-layer coding techniques, actually complementing the lower layers channel coding schemes. |
Goals | The targets mentioned above shall be achieved by defining the methods by which data can be sent from a source to a destination such that distinct messages can be easily distinguishable from one another and their reconstruction can be performed with low error probability, thus improving the performance of the channel. The Coding and Synchronization WG shall provide/maintain standards to be applied to Telemetry, Telecommand and Proximity-1 links to allow Agencies to implement the most appropriate Coding & Synchronization procedures. The characteristics of the codes shall be specified only to the extent necessary to ensure interoperability and cross-support. Correct interaction with the procedures at the Data Link Procol and RF and Modulation layers shall be ensured too. These goals shall be achieved by updating the existing set of Channel Coding Books by either modifying existing books or creating new books as required and described in the WG Projects. Current goals/projects are:
Update TM channel coding Blue Book with LDPC Codes (COMPLETED)
Update TM channel coding green book with LDPC Codes etc (COMPLETED)
Blue Book for SCC Codes (COMPLETED)
Blue Book for DVB-S2 Codes (COMPLETED)
Magenta Book on TM Channel Coding Application Profiles (COMPLETED)
Orange Book on Erasure Correcting Codes for Near-Earth and Deep-Space Communications
Update of CCSDS 230.1-G, “TC Sync and Channel Coding Green Book” (COMPLETED)
Review Proximity-1 Coding and Synchronization Sublayer. Blue Book (5 years review) (COMPLETED)
Update Proximity-1 Coding and Synchronization Sublayer. Blue Book with Improved Coding Schemes (COMPLETED)
Orange Book on Short (64, 128, 256 bit ) LDPC codes for uplink
Update TM channel coding green book with SCC Codes
Update CCSDS 231.0-Blue Book with new channel coding schemes for the Telecommand (TC) link
Update CCSDS 230.1-G Informational Report to add material relative to the new coding technique(s) as per updated CCSDS 231.0-Blue Book.
Magenta Book for Variable Code and Modulation (VCM)
Update TM channel coding Blue Book with LDPC slicing |
Survey of Similar Standards Efforts Undertaken in
Other Bodies and elsewhere in CCSDS | |
Patent Licensing Applicability for Future Standards | YES - The WG is working on patented technologies for 3 items: LDPCC, SCCC and DVB-S2 |
Technical Risk Mitigation Strategy | No technical risks have been identified. |
Management Risk Mitigation Strategy | The schedule is very dependent upon Agency commitment of resources and the use of the same personnel working on concurrent CCSDS tasks. |
