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|author=K. Schouhamer Immink
|authorlink=Kees Schouhamer Immink
|url=https://www.researchgate.net/publication/
|pages=751–764
|accessdate=2018-02-05
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== Transmission and storage ==
After line coding, the signal is put through a physical communication channel, either a [[transmission medium]] or [[data storage medium]].<ref name="paulsen">Karl Paulsen. [http://www.tvtechnology.com/media-servers/0150/coding-for-magnetic-storage-mediums/186738 "Coding for Magnetic Storage Mediums"] {{Webarchive|url=https://web.archive.org/web/20140521215946/http://www.tvtechnology.com/media-servers/0150/coding-for-magnetic-storage-mediums/186738 |date=2014-05-21 }}.2007.</ref><ref>{{citation|author1=Abdullatif Glass |author2=Nidhal Abdulaziz |author3=and Eesa Bastaki |url=http://ro.uow.edu.au/cgi/viewcontent.cgi?article=1285&context=dubaipapers|title=Slope line coding for telecommunication networks|year=2007|
* the line-coded signal can directly be put on a [[transmission line]], in the form of variations of the voltage or current (often using [[differential signaling]]).
* the line-coded signal (the "[[baseband]] signal") undergoes further [[pulse shaping]] (to reduce its frequency bandwidth) and then [[modulation|modulated]] (to shift its frequency) to create an "[[RF signal]]" that can be sent through free space.
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== Disparity ==
Most long-distance communication channels cannot reliably transport a [[DC component]]. The DC component is also called the ''disparity'', the ''bias'', or the [[DC coefficient]]. The disparity of a bit pattern is the difference in the number of one bits vs the number of zero bits. The ''running disparity'' is the [[running total]] of the disparity of all previously transmitted bits.<ref>{{cite
Most line codes eliminate the DC component{{snd}} such codes are called [[DC-balanced]], zero-DC, or DC-free. There are three ways of eliminating the DC component:
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|author=Kees Schouhamer Immink
|authorlink=Kees Schouhamer Immink
|url=https://www.researchgate.net
|pages=1745–1759
|quote=A detailed description is furnished of the limiting properties of runlength limited sequences.
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|author=Kees Schouhamer Immink
|authorlink=Kees Schouhamer Immink
|url=https://www.researchgate.net/publication/
|pages=491–497
|quote=A high-density alternative to EFM is described.}}</ref> Higher density RLL (2,7) and RLL (1,7) codes became the [[de facto standard]]s for hard disks by the early 1990s.{{citation needed|date=August 2019}}
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== Other considerations ==
A line code will typically reflect technical requirements of the transmission medium, such as [[optical fiber]] or [[shielded twisted pair]]. These requirements are unique for each medium, because each one has different behavior related to interference, distortion, capacitance and loss of amplitude.<ref>{{Cite book|url=https://books.google.com/books?id=On_Hh23IXDUC&pg
== Common line codes ==
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