On the equivalence of interleavers for turbo codes using quadratic permutation polynomials over integer rings
On the equivalence of interleavers for turbo codes using quadratic permutation polynomials over integer rings
复制标题
整数环上二次置换多项式的Turbo码交织器的等价性
DOI:
10.1109/lcomm.2010.03.091695
复制
发表时间:
2010
期刊:
影响因子:
--
通讯作者:
V. Tarokh
中科院分区:
文献类型:
--
作者:
H. Zhao;P. Fan;V. Tarokh
It is known that the equivalence of interleavers for turbo codes using quadratic permutation polynomials (QPPs) over integer rings can be exactly determined by the so-called quadratic null polynomials (QNPs) over integer rings. For generating QNPs or higher order null polynomials (NPs), some theoretical results have been obtained in previous literature. In this letter, it is proved that the coefficients of previously obtained QNPs are not only sufficient but also necessary for generating any QNPs. Based on the necessary and sufficient conditions for generating QNPs and QPPs, the enumeration of QPPs excluding their equivalence is presented. The obtained results are helpful to investigate the algebraic structure of QPP interleavers as well as to avoid the equivalence in the design of QPP interleavers.