LDPC Convolutional Codes Based on Permutation Polynomials over Integer Rings

نویسندگان

  • Marcos B. S. Tavares
  • Gerhard P. Fettweis
چکیده

A novel algebraic construction technique for LDPC convolutional codes (LDPCCCs) based on permutation polynomials over integer rings is presented. The underlying elements of this construction technique are graph automorphisms and quasi-cyclic (QC) codes. The algebraic structure of the obtained LDPCCCs, their encoding and decoding are discussed. These new codes have a special structure, which is favorable for high-rate VLSI implementations. Their performances in the asymptotic case are superior to that of the QC codes from which they are derived at a much lower complexity. 1

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A New Construction for LDPC Codes using Permutation Polynomials over Integer Rings

A new construction is proposed for low density parity check (LDPC) codes using quadratic permutation polynomials over finite integer rings. The associated graphs for the new codes have both algebraic and pseudorandom nature, and the new codes are quasi-cyclic. Graph isomorphisms and automorphisms are identified and used in an efficient search for good codes. Graphs with girth as large as 12 wer...

متن کامل

Optimization-Based Decoding Algorithms for LDPC Convolutional Codes in Communication Systems

In a digital communication system, information is sent from one place to another over a noisy communication channel. It may be possible to detect and correct errors that occur during the transmission if one encodes the original information by adding redundant bits. Low-density parity-check (LDPC) convolutional codes, a member of the LDPC code family, encode the original information to improve e...

متن کامل

On Inverses for Quadratic Permutation Polynomials over Integer Rings

Quadratic permutation polynomial interleavers over integer rings have recently received attention in practical turbo coding systems from deep space applications to mobile communications. In this correspondence, a necessary and sufficient condition that determines the least degree inverse of a quadratic permutation polynomial is proven. Moreover, an algorithm is provided to explicitly compute th...

متن کامل

Codeword Structure Analysis for LDPC Convolutional Codes

The codewords of a low-density parity-check (LDPC) convolutional code (LDPC-CC) are characterised into structured and non-structured. The number of the structured codewords is dominated by the size of the polynomial syndrome former matrix H (D), while the number of the non-structured ones depends on the particular monomials or polynomials in H (D). By evaluating the relationship of the codeword...

متن کامل

On the Enhancement of LDPC Codes Used in WiMAX

In this paper the low density party check (LDPC) codes used in the IEEE 802.16 standard physical layer are studied, and two novel techniques to enhance the performance of such codes are introduced. In the first technique, a novel parity check matrix for LDPC codes over GF(4) with the non-zero entries chosen to maximize the entropy is proposed, the parity check matrix is based on the binary pari...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2006