Space Communications and Navigation Program
NASA’s SCaN (Space Communications and Navigation) Program places the three prime NASA networks under one management/engineering umbrella. These networks are the Space Network (SN), Near Earth Network (NEN, previously known as the Ground Network or GN), and the Deep Space Network (DSN).
History
Traditionally, a number of different organizations at NASA Headquarters have managed the Agency’s space communications capabilities and functions under separate Programs using a variety of administrative approaches. NASA's Administrator created SCaN as a central organization within the Space Operations Mission Directorate (SOMD) to direct an integrated networks program.[1]
Services
SCaN is viewed as a service provider supporting interfaces and performing a standard set of functions, including:[2]
- Forward data transfer (uplink to spacecraft)
- Return data transfer (downlink from spacecraft to ground)
- Dissimilar voice communications
- Emergency communications
- Post-landing communications
- Radiometric measurement
- Time correlation
- Service monitoring
- Ephemeris exchange
- Operational coordination
- Service scheduling.
Forward and return services may be MA (Multiple Access) or SA (Single Access).
Communications schemes
Communications with spaceborne platforms is performed by RF, with a selection of spectra and modulation and encoding methods.
Spectra
The Space Network communicates with spacecraft using S-band, Ka-band, and Ku-band.[3]
Modulation
SN uses Phase Shift Keying and Phase Modulation of the carrier frequency.[3]
Encoding Schemes
The Space Network supports the following encoding schemes:[3]
Applicability to Constellation
The Constellation missions will be different from previous NASA campaigns, in that the number of simultaneously interacting space and ground systems will be larger, and systems will need to coordinate with each other both to achieve their science objectives and to accomplish the 'routine' mechanics of mission operations. The interaction between combinations of these systems is important." The small set of Constellation links is based on the Space Network (SN) standards that are currently used in human spaceflight.[4]
References
- ^ NASA. Space Communications and Navigation (SCaN) Program Plan. National Aeronautics and Space Administration.
{{cite book}}: Cite has empty unknown parameter:|coauthors=(help) - ^ NASA (June 28, 2008). Constellation Design Reference Missions And Operational Concepts (ConOps), Annex 1: Constellation Communications and Tracking Concept of Operations (Baseline ed.). National Aeronautics and Space Administration. CxP 70007, ConOps.
{{cite book}}: Cite has empty unknown parameter:|coauthors=(help)CS1 maint: year (link) - ^ a b c NASA, Exploration and Space Communications Projects Division (August 2007). Space Network User's Guide (SNUG), 2.3, Elements of the SN (Rev 9 ed.). National Aeronautics and Space Administration. 450-SNUG.
{{cite book}}: Unknown parameter|coauthors=ignored (|author=suggested) (help)CS1 maint: year (link) Cite error: The named reference "SNUG" was defined multiple times with different content (see the help page). - ^ NASA (September 8, 2008). CxP 70022-2 Rev. B, Constellation Program Command, Control, Communication, and Information (C3I) Interoperability Standards Book, Volume 2: Spectrum And Channel Plan (Rev. B ed.). National Aeronautics and Space Administration. CxP 70022-2.
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See also
- Space Network
- Deep Space Network
- Near Earth Network
- Indian Deep Space Network
- Tracking and Data Relay Satellite
- Eastern Range
References