decode.hlp

数字通信第四版原书的例程

ha_help_begin
DECODE Decodes an encoded codeword using Hamming code method.
       MSG = DECODE(CODE, N, K, METHOD), METHOD = 'hamming', decodes the
       binary codeword in CODE using Hamming code method. The codeword length
       is N and the message length is K. The format of CODE can be either
       a vector or N column matrix. Hamming code is a single error-correction
       code. Its codeword length is N = 2^M-1. Its message length is N-M. 

       MSG = DECODE(CODE, N, K, METHOD, P_POLY), METHOD = 'hamming', specifies
       the primitive polynomial used in the Hamming decode. P_POLY is a degree
       N polynomial defined in GF(2).

       MSG = DECODE(CODE, N, K, METHOD...), METHOD = 'hamming/decimal'
       specifies that the input data in CODE is decimal integers. This
       function converts the decimal integer into M bits binary before
       proceeding with the decode computation, where M is the smallest integer
       such that N <= 2^M-1.

       [MSG, ERR, CCODE, CERR] = DECODE(...) outputs the decode message signal
       MSG, the number of errors detected in ERR, the corrected codeword
       CCODE, and errors found in CODE.
ha_help_end

bl_help_begin
DECODE Decodes an encoded codeword using linear block code method.
       MSG = DECODE(CODE, N, K, METHOD, GEN), METHOD = 'linear', decodes the
       binary codeword in CODE using linear block code method. The codeword
       length is N and the message length is K. The format of CODE can be 
       either a vector or N column matrix. The generator matrix GEN is a
       K-by-N matrix. Linear block code is a generic code. For example, You
       may use HAMMGEN function to generate a generator matrix for Hamming 
       code.

       MSG = DECODE(CODE, N, K, METHOD, GEN, TRU_TBL), METHOD = 'linear',
       specifies the error-correction truth table in the linear block code.
       For a single-error correction code, you can use function HTRUTHTB to
       produce an error-correction truth table.

       MSG = DECODE(CODE, N, K, METHOD...), METHOD = 'linear/decimal' specifies
       that the input data in CODE is decimal integers. This function converts
       the decimal integer into M bits binary before proceeding with the
       decode computation, where M is the smallest integer such that
       N <= 2^M-1.

       [MSG, ERR, CCODE, CERR] = DECODE(...) outputs the decode message signal
       MSG, the number of errors detected in ERR, the corrected codeword CCODE,
       and errors found in CODE.
bl_help_end

cy_help_begin
DECODE Decodes an encoded codeword using cyclic code method.
       MSG = DECODE(CODE, N, K, METHOD, CYC_POLY), METHOD = 'cyclic', decodes
       binary codeword in CODE using cyclic code method. The codeword length
       is N and the message length is K. The format of CODE can be either
       a vector or N column matrix. CYC_POL is a degree N-K cyclic polynomial.
       You can use function CYCLPOLY to produce the cyclic polynomial. This
       format uses the default single error correction truth table.

       MSG = DECODE(CODE, N, K, METHOD, CYC_POLY, TRU_TBL), METHOD = 'cyclic',
       specifies the error-correction truth table in the linear block code.
       For a single-error correction code, you can use function HTRUTHTB to
       produce an error-correction truth table.

       MSG = DECODE(CODE, N, K, METHOD...), METHOD = 'cyclic/decimal',
       specifies that the input data in CODE is decimal integers. This
       function converts the decimal integer into M bits binary before
       proceeding with the decode computation, where M is the smallest integer
       such that N <= 2^M-1.

       [MSG, ERR, CCODE, CERR] = DECODE(...) outputs the decode message signal
       MSG, the number of errors detected in ERR, the corrected codeword
       CCODE, and errors found in corresponding to each row of CCODE.
cy_help_end

bc_help_begin
DECODE Decodes an encoded codeword using BCH code method.
       MSG = DECODE(CODE, N, K, METHOD), METHOD = 'bch', decodes binary
       codeword in CODE using cyclic code method. The codeword length is N and
       the message length is K. The format of CODE can be either a vector or
       N column matrix. Use BCHPOLY to view the valid codeword length, message
       length, and error-correction capability of BCH code.

       MSG = DECODE(CODE, N, K, METHOD, T), METHOD = 'bch', specifies the
       error-correction capability of the BCH code.

       MSG = DECODE(CODE, N, K, METHOD, T, GEN_POLY), METHOD = 'bch',
       specifies the generator polynomial for the BCH code.

       MSG = DECODE(CODE, N, K, METHOD...), METHOD = 'bch/decimal' specifies
       that the input data in CODE is decimal integers. This function converts
       the decimal integer into M bits binary before proceeding with the
       decode computation, where M is the smallest integer such that
       N <= 2^M-1.

       [MSG, ERR, CCODE, CERR] = DECODE(...) outputs the decode message signal
       MSG, the number of errors detected in ERR, the corrected codeword
       CCODE, and errors in CODE.
bc_help_end

rs_help_begin
DECODE Decodes an encoded codeword using Reed-Solomon code method.
       MSG = DECODE(CODE, N, K, METHOD), METHOD = 'rs', decodes the binary 
       codeword in CODE using Reed-Solomon code method. The codeword length
       is N and the message length is K. In R-S code, N must equal to 2^M-1,
       where M is an integer larger than or equal to 3. The error-correction
       capability for R-S code is T = floor((N-K)/2). For efficiency, N-K 
       should be an even number. The format of CODE can be either a vector
       or a N*M column matrix. The function generates a list of all elements
       in GF(2^M) before the calculation.

       MSG = DECODE(CODE, N, K, METHOD, GF_TP), METHOD = 'rs', provides all
       elements in GF(2^M) for the calculation. You can use function GFTUPLE
       to generate the list of all elements in GF(2^M).

       MSG = DECODE(CODE, N, K, METHOD...), METHOD = 'rs/decimal' specifies
       that the input data in CODE is decimal integer matrix. CODE must be an
       N column matrix in this format. The decimal integer should be in range
       [0, N-1].

       MSG = DECODE(CODE, N, K, METHOD...), METHOD = 'rs/power' specifies
       that the elements in CODE are elements in GF(2^M) in power form 
       (exponential form). CODE must be an N column matrix in this format. The
       decimal integers should be integers not larger than N-2.

       [MSG, ERR, CCODE, CERR] = DECODE(...) outputs the decode message signal
       MSG, the number of errors detected in ERR, the corrected codeword
       CCODE, and errors found in CODE.
rs_help_end

co_help_begin
DECODE Decodes a convolution codeword Viterbi algorithm.
       MSG = DECODE(CODE, N, K, METHOD, TRAN_FUNC), METHOD = 'convolution',
       decodes binary codeword in CODE using convolution code method. This 
       function uses Viterbi algorithm. The codeword length is N and the 
       message length is K. The format of CODE can be either a vector or
       N column matrix. The convolution code transfer function TRAN_FUNC is
       in octal form, which is a K-by-N matrix. You can use function SIM2GEN
       to generate a convolution code transfer function using SIMULINK block
       diagram. 

       MSG = DECODE(CODE, N, K, METHOD, TRAN_FUNC, DELY_LEN), METHOD = 
       'convolution', specifies the computation delay length in DELY_LEN. The
       delay length must be an integer, which determines the longest length of
       the trellis kept in memory before making the decision. If DELY_LEN is
       a non-positive number or it is absent, this function uses the default
       infinite delay length.

       MSG = DECODE(CODE, N, K, METHOD, TRAN_FUNC, DELY_LEN, TRAN_PROB), 
       METHOD = 'convolution', specifies soft-decision transfer probability.
       TRAN_PROB is a three row matrix. When TRAN_PROB is absent or it is not
       an three row matrix, this function processes the decode using the
       default hard decision.

       MSG =DECODE(CODE, N, K, METHOD, TRAN_FUNC, DELY_LEN, TRAN_PROB, P_NUM),
       METHOD = 'convolution', specifies the figure number in plotting the
       convolution code trellis. P_NUM should be a positive integer. If P_NUM
       is a non-positive number or it is absent, no trellis plot figure is
       opened. The plot for the trellis figure is very expensive in
       computation.

       [MSG, ERR, CCODE, CERR] = DECODE(...) outputs the decode message signal
       MSG, the number of errors detected in ERR, the corrected codeword
       CCODE, and errors found in CODE.
co_help_end       

Wes Wang 10/5/95