A new scheme for the construction of m-out-of* codesbased on the arithmetic coding technique is described. For appropriatevalues of n , k , and m, the scheme can be used to construct an (n,k)Mock code in which all the...
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A new scheme for the construction of m-out-of* codes
based on the arithmetic coding technique is described. For appropriate
values of n , k , and m, the scheme can be used to construct an (n,k)
Mock code in which all the.codewords are of weight m. Such codes
are useful, for example, in providing perfect error detection capabil-
ity in asymmetric channels such as optical communication links and
laser disks. The encoding and decoding algorithms of the scheme per-
form simple arithmetic operations recursively, thereby facilitating the
construction of codes with relativelylong Mock sizes. The scheme also
allows the construction of optimal or naarly optimal m-out-of* codes
for a wide range of block sizes limited only by the arithmetic precision
used.
In the information theory of the multiple-access channel, two types of synchronism are usually assumed among the transmitters, namely, frame and symbol synchronism. Frame synchronism refers to the ability of the users...
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In the information theory of the multiple-access channel, two types of synchronism are usually assumed among the transmitters, namely, frame and symbol synchronism. Frame synchronism refers to the ability of the users to start the transmission of their.codewords in unison. The issue of symbol synchronism arises in continuous-time channels in which each codeword symbol modulates a fixed assigned waveform; the channel is symbol synchronous if the users cooperate so that their symbol epochs coincide at the receiver. In practice symbol synchronism is harder to achieve, yet the only reported progress so far has been in the removal of the assumption of frame synchronism. It is shown that if the transmitters are assigned the same waveform, symbol asynchronism has no effect on the two-user capacity region of the white Gaussian channel which is equal to the Cover-Wyner pentagon, whereas if the assigned waveforms are different (e.g., code d&ion multiple access), the symbol-asynchronous capacity region is no longer a pentagon.
The Hamming distance concept is applied to modulation code to improve the error detection capability of the demodulator. It will be helpful to increase the error correction capability for the subsequent error correction.
The Hamming distance concept is applied to modulation code to improve the error detection capability of the demodulator. It will be helpful to increase the error correction capability for the subsequent error correction.
Simulated annealing is a computational heuristic for obtain- ing approximate solutions to combinatorial optimization problems. It is used to construct good source codes, error-correcting codes, and spherical codes. Fo...
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Simulated annealing is a computational heuristic for obtain- ing approximate solutions to combinatorial optimization problems. It is used to construct good source codes, error-correcting codes, and spherical codes. For certain sets of parameters codes that are better than any other known in the literature are found.
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