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Unformatted text preview: the process ends with the last bit of the
Input Data. The randomization may also be applied to the fill bits added after the end of the
Input Data to complete the last codeblock of the CLTU, but this is optional.
At the receiving end, the derandomization is applied to the successfully decoded TC data.
The BTG remains in the “all-ones” state until the CLTU Start Sequence has been detected.
The BTG pattern is exclusively ORed, bit by bit, to the successfully decoded data (after the
Error Control Bits have been removed). The BTG is reset to the “all-ones” state following a
failure of the decoder to successfully decode a TC codeblock or other loss of TC data.
3.3.2 TC CODEBLOCK ENCODING PROCEDURE A systematic block coding procedure is used which always generates 7 parity check bits per
codeblock and which is always computed from 56 information bits. The parity check bits are
then COMPLEMENTED and placed into the codeblock as shown in Figure 3-1.
The code used is a (63,56) modified Bose-Chaudhuri-Hocquenghem (BCH) code which uses
the following generator polynomial to pro...
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This document was uploaded on 03/06/2014.
- Spring '14