摘要:
A transmitting apparatus transmits a plurality of data packets to a receiver in a communication system, by transmitting one or more data packets from a list of data packets to be transmitted, and determining whether an acknowledgment is received for each transmitted data packet. When it is determined that an acknowledgement has not been received for at least one data packet, referred to as an unacknowledged data packet, the apparatus selects one or more additional data packets from the list of data packets to be transmitted, generates one or more parity packets by encoding a block of data containing a combination of the selected one or more additional data packets and at least one unacknowledged data packet using a forward error correction scheme, and transmits at least one of the generated parity packets.
摘要:
The invention relates to a method for transmitting a plurality of data packets to a receiver in a data communication system. The method comprises the steps of transmitting one or more data packets from a list of data packets to be transmitted (300); determining whether an acknowledgment is received for each transmitted data packet (301), and further comprises the following steps executed when it is determined at the determining step that an acknowledgement has not been received for at least one data packet, referred to as an unacknowledged data packet: selecting one or more additional data packets from the list of data packets to be transmitted (302); generating one or more parity packets by encoding a block of data containing a combination of the selected one or more additional data packets and at least one unacknowledged data packet using a forward error correction scheme (304); and transmitting at least one of the generated parity packets (305).The invention also relates to software applications for transmitting a plurality of data packets and for receiving them. Furthermore, the invention relates to a transmitting device and a receiving device implementing respectively the software application for transmitting the plurality of data packets and the software application for receiving those data packets, and to a memory medium for storing the code of such software applications.
摘要:
A method of decoding a one-point algebraic geometric code defined on an algebraic curve of the kind C(a,b), represented by an equation of degree b in X and of degree a in Y. For any received word, transmission errors affecting the received word are located. The correction of errors in the word, which belongs to an algebraic geometric code, is then reduced to the correction of errors in a certain number, at most equal to a, of words belonging to a Reed-Solomon code. Devices and apparatuses adapted to implement this method are also described.
摘要:
The present invention relates to a method of decoding a one-point algebraic geometric code defined on an algebraic curve of type C(a,b) represented by an equation F(X,Y)=0 of degree b in X and of degree a in Y over Fq, comprising the following steps: —calculating extended error syndromes (σj(i)) associated with a received word (r); —determining the values of errors in each component (r(x, yp(x))) of the received word r, on the basis of the extended error syndromes calculated. Since the error value is determined for each component, it is not necessary to have recourse to an error locating step. The invention also relates to devices and apparatuses associated with the method.
摘要:
A method of decoding a one-point algebraic geometric code defined on an algebraic curve of type C(a,b) represented by an equation F(X,Y) =0 of degree b in X and of degree a in Y over Fq, includes calculating extended error syndromes (σj(i)) associated with a received word (r) and determining the values of errors in each component r(x,yp,(x)) of the received word r, on the basis of the extended error syndromes calculated.
摘要:
A method of encoding information symbols comprises a step in which a word v, orthogonal to a matrix H, the element Hαβ of which is equal to the value taken by some monomial hα=YjXi at the point Pβ of some locating set, is associated with every block of k information symbols belonging to a Galois field Fq. The method chooses the set of monomials hα so as to define codes which can be decoded with an algorithm by aggregates of low complexity, and which provides a very good error correction capability, in particular for channels in which the errors tend to occur in bursts. Devices and apparatuses adapted to implement this method are also disclosed.
摘要:
The present invention concerns a device (10) for the encoding of information symbols to transmit or to record, and for the correction of errors among the symbols received or read, according to codes defined over a Galois field Fq, where q is an integer greater than 2 and equal to a power of a prime number, and in which a set of elements of Fq are considered which are denoted yl(j), where j=1, . . . , R with 1≦R≦q−1 and l=0, . . . , p−1 with p>1. Said device (10) comprises a Reed-Solomon encoder (210), a Reed-Solomon decoder (220) and a unit (500) serving to calculate the inverse of a Vandermonde matrix as well as: registers “A” (420, 430, 440, 450) in which are stored, for the encoding, said information symbols, and, for the error correction, the symbols received or read after they have been corrected, registers “S” (280, 285, 290, 295) in which are stored, for the encoding, the symbols output from said Reed-Solomon encoder (210), and, for the error correction, the symbols entering said Reed-Solomon decoder (220), and registers “Y” (410, 411, 412, 413) in which said quantities yl(j) are stored.
摘要:
The present invention concerns channel codes particularly well adapted to transmission in channels in which errors tend to occur in bursts. Moreover, the codes according to one embodiment of the invention using an algebraic geometric curve are easy to decode and have a relatively high minimum distance. The invention also relates to the corresponding encoding and decoding methods, as well as the devices and apparatuses adapted to implement those methods. Application is in particular to mass storage, and to systems of communication by OFDM.
摘要:
The present invention concerns an encoding method in which encoding is performed of any information word a of length k in the form of a word ν belonging to a Reed-Solomon code C of dimension k′ and length n′ (with n′−k′=n−k) such that the components of ν′ situated in (n′−n) arbitrary predetermined positions be systematically equal to respective predetermined constants (for example, all zero). The possibility then exists of deleting those components of fixed value to obtain a word ν of length n belonging to a code C, which thus constitutes a code that is shortened with respect to code C. The invention also relates to devices and apparatuses adapted to implement the encoding method. The invention may be used for encoding by means of an algebraic geometric code, when such encoding may be implemented by encoding by means of a plurality of shortened Reed-Solomon codes.
摘要:
The present invention concerns a method and apparatus of decoding a one-point algebraic geometric code defined on an algebraic curve represented by an equation in X and Z of degree 2μφ in Z, where φ is a strictly positive integer and μ an integer greater than 1, obtained by taking the fiber product of μ component algebraic equations, each of said component equations governing the unknown X and an unknown Yi, where i=0, . . . , μ−1, and being of degree 2φ in Yi. This method comprises the decoding of 2(μ−1)φ “clustered” codes, all defined on the same algebraic curve represented by one of said component equations.