Wavecom W-BitView V2.5.00 - Manual (Page 100)

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Glossary of Terms BitView Manual V2.5.00 WAVECOM W-BV
Huffman coding
Huffman coding is an entropy encoding algorithm used for lossless data compression. The term refers to
the use of a variable-length code table for encoding a source symbol (such as a character in a file) where
the variable-length code table has been derived in a particular way based on the estimated probability of
occurrence for each possible value of the source symbol. It was developed by David A. Huffman
LZ77
LZ77 is the name for a lossless data compression algorithms published in papers by Abraham Lempel and
Jacob Ziv. LZ77 algorithms achieve compression by replacing portions of the data with references to
matching data that has already passed through both encoder and decoder.
Matlab
MATLAB is a numerical computing environment and programming language. Created by The MathWorks,
MATLAB allows easy matrix manipulation, plotting of functions and data, implementation of algorithms,
creation of user interfaces, and interfacing with programs in other languages. Although it specializes in
numerical computing, an optional toolbox interfaces with the Maple symbolic engine, allowing it to be part
of a full computer algebra system.
Puncturing
Puncturing is a procedure whereby a code with code rate 1/2 is transformed to another code rate by
deleting some bits (“erasures”) for the encoder output bit stream. The deletion is done according to a
puncturing matrix. The erasures must be re-inserted in the received bit stream for a Viterbi decoder to
work properly.