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PCE
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DIFF Subgroup
H04L 25/49

using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels

Introduced: July 1974

Full Title

Baseband systems > Synchronous or start-stop systems, e.g. for Baudot code > Transmitting circuits; Receiving circuits > using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels

CPC subdivides this area 3x more granularly than IPC with 4 additional codes.

4 codes are CPC-only extensions.

IPC defines codes here since 1980.

Child Classifications

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  • H04L 25/4902 CPC only CPC only
  • H04L 25/4904 CPC only CPC only
  • H04L 25/493 by transition coding, i.e. the time-position or direction of a transition being encoded before transmission since 1980 IPC+CPC Available in IPC and CPC