Wavecom W-BitView V2.5.00 - Manual (Page 45)

BitView Manual V2.5.00 WAVECOM W-BV Function Library
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Function:
This function performs difference decoding, which is a logical XOR operation on the previous output bit
and the current input bit. The Start bit value is user defined.
Example with start bit value of ‘1’:
“01101110” is changed to “10110100”.
BCH-Decoding
In: Bit stream
Out: Bit stream
Function:
Decodes BCH encoded bit streams.
The function returns the parameters listed in the table below.
Parameter Description
Corrected errors Number of corrected errors
Error Positions Positions of detected errors
Generator Polynomial Encoding generator polynomial on the form g(x) = 111…
Minimum distance This property determines the number of detectable errors and the number of correctable
errors
Number of frames Number of frames in the decoded bit stream
Order of Galois field Property of the field of numbers to which a given BCH code belongs
Original data length Length of original code word
Primitive polynomial A polynomial describing a given BCH code
Parameter Description Value
BCH algorithm Algorithm used to find BCH polynomial Berlekamp-Massey, Euclid
Code word length Length of code word including redundancy
bits.
Max errors Error correction capability