Let X be an algebraic curve of genus g ≥ 2 defined over a field Fq of characteristic p > 0. From X , under certain conditions, we can construct an algebraic geometry code CX . When this code (or its dual) is self-orthogonal under the symplectic product, a quantum algebraic geometry code QX is constructed. In this paper we study the construction of such codes from curves with automorphisms and t...

Instead of a random interleaver, an algebraic interleaver interconnecting two simple convolutional codes with feedback encoders forms an algebraic quasi-cyclic code. An (nC , k) convolutional code in tailbiting form becomes a quasi-cyclic (QC) linear code of length LnC for some L = Mn. Interleavers with a period M connect two such codes to produce a QC turbo code. The QC turbo codes check equat...

Since 2003, Algebraic Attacks have received a lot of attention in the cryptography literature. In this context, algebraic immunity quantifies the resistance of a Boolean function to the standard algebraic attack of the pseudo-random generators using it as a nonlinear Boolean function. A high value of algebraic immunity is now an absolutely necessary cryptographic criterion for a resistance to a...

Codes which reduce the peak-to-average power (PAPR) in multi-code code division multiple access (MC-CDMA) communications systems are systematically studied. The problem of designing such codes is reformulated as a new coding-theoretic problem: codes with low PAPR are ones in which the codewords are far from the rst-order ReedMuller code. Bounds on the trade-o between rate, PAPR and error-correc...

Similar to algebraic decoding schemes, the (23, 12, 7) Golay code can be decoded by applying the step-by-step decoding algorithm. In this work, a modified step-by-step algorithm for decoding the Golay code is presented. Logical analysis yielded a simple rule for directly determining whether a bit in the received word is correct. The computational complexity can be reduced significantly using th...

Speech coding algorithms based on Algebraic Code Excited Linear Prediction (ACELP) quantize and code the residual signal with a fixed algebraic codebook. This paper generalizes the conventional encoding to provide optimal bit consumption for all codebook designs by enumerating all possible states. The codebook designed is aimed for constant bit-rate applications applied on mobile devices.

In this paper, it is proved that any algehraicgeometr ic code can be expressed as a cross section of an extended multidimensional cyclic code. Both algebraic-geometric codes and multidimensional cyclic codes are descr ibed by a unified theory of l inear block codes def ined over point sets: algebraic-geometric codes are def ined over the points of an algebraic curve, and an m-dimensional cyclic...

The algebraic Kekulé structure of a finite catacondensed benzenoid graph with h hexagons is described by a binary code of length h. The procedure can be reversed, any (algebraic) Kekulé structure can be recovered from its binary code. c © 2007 Elsevier Ltd. All rights reserved.

We present a practical expected usually quartic time algorithm to recover the structure of an algebraic geometry code defined over a hyperelliptic code of genus g ≤ 2. Its main application is an attack of the McEliece cryptosystem based on algebraic geometry codes defined over curves of small genus. Our algorithm is a adaptation of the well-known Sidelnikov-Shestakov algorithm [6].