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Nasa-verve (talk | contribs) →Applicability to Constellation: not relevant since change in HSF architecture |
Added missing word "coding" in list of SN encoding. Removed K-band from DSN (leaving only S, X, and Ka). Added explanatory comment about why PN coding is used for SN |
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The Space Network communicates with spacecraft using [[S-band]], [[Ku-band]]<ref name="SNUG">{{cite book| title =Space Network User's Guide (SNUG), 2.3, Elements of the SN | edition = Rev 9| last = NASA| first = Exploration and Space Communications Projects Division | coauthors = Goddard Space Flight Center| year = August 2007 | publisher = National Aeronautics and Space Administration| id =450-SNUG | pages = }}</ref>, and [[Ka-band]] with planned laser/optical communications.
The Deep Space Network communicates with spacecraft using S-band, [[X
===Modulation===
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===Encoding===
The Space Network (used for near-Earth communications) supports the following encoding schemes:<ref name="SNUG">{{cite book| title =Space Network User's Guide (SNUGx)| edition = Rev 9| last = NASA| first = Exploration and Space Communications Projects Division | coauthors = Goddard Space Flight Center| year = August 2007 | publisher = National Aeronautics and Space Administration| id =450-SNUG | pages = }}</ref>
* [[BPSK]]
* [[QPSK]]/[[SQPSK]]
* [[8PSK]]
* Rate 1/2 [[Convolutional code|convolutional coding]]
* [[Phase-shift keying|SQPN]]
* [[Pseudorandom noise|PN coding]] - used to reduce power spectral density for low bit rate signals, and for time transfer.
The [[Reed-Solomon]] method is used as the initial [[error-correcting code|error-correcting]] [[block code]] prior to the selected secondary encoding scheme.
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