PERFECT PUNCTURED BINARY SEQUENCE PAIRS

This paper presents the definition of perfect punctured binary sequence pair and the combinatorial admissible conditions for searching the perfect punctured binary sequence pairs and proves that all of the pseudo-random binary sequences satisfy these conditions. Computer calculation verifies that the pseudo-random binary sequences with length up to N=127 can be easily turned into perfect punctured binary sequence pairs.     

The constructions of almost binary sequence pairs with three-level correlation based on cyclotomy

In this paper, a new class of almost binary sequence pair with a single zero element is presented. The almost binary sequence pairs with three-level correlation are constructed based on cyclotomic numbers of order 2, 4, and 6. Most of them have good correlation and balance property, whose maximum nontrivial correlation magnitudes are 2 and the difference between the numbers of occurrence of +1’s and ′-1’s are 0 or 1. In addition, the corresponding binary sequence pairs are investigated as well and we can also get some kinds of binary sequence pairs with optimum balance and good correlation.     

Complementary sequences for ISI channel estimation

A merit factor based on the sequence autocorrelation function, whose minimization leads to the reduction in the Cramer-Rao lower bound (CRLB) for the variance of “two-sided” intersymbol interference (ISI) channel estimation is introduced. Pairs of binary pilot symbol sequences (a preamble and a postamble) for channel estimation are jointly designed to minimize this merit factor. Given that the number of channel taps is L and the length of a pilot symbol sequence is (N+L-1), where N⩾L, we distinguish between the case when N is even and the case when it is odd. For even N, we show that complementary sequences not only minimize the merit factor, but also the CRLB. For a subset of odd N we construct almost-complementary periodic sequence pairs that minimize the merit factor. The optimal pilot symbol block signaling requires alternating between two (in most cases) different binary sequences that form the merit-minimizing pair     

Class of ternary spreading sequences with zero correlation duration

Novel ternary preferred pairs (TPPs) that have a greater zero correlation duration (ZCD) of (0.75 N+1) for a period N are constructed by applying selected zero padding to binary preferred pairs with ZCD of (0.5 N+1). A chip-shift operation is then performed to derive new ternary ZCD sequences that have superior family size to that of binary ZCD sequences     

最佳屏蔽二进序列偶在低/零相关区中的应用研究

将最佳屏蔽二进序列偶应用于低/零相关区中,提出最佳屏蔽低/零相关序列偶集的概念,给出了3种构造低/零相关序列偶集的方法,即奇数长最佳屏蔽二进序列偶与Hadamard矩阵相结合组成ZCZ(零相关区)序列集,偶数长最佳屏蔽二进序列偶与改造后的Hadamard矩阵组成LCZ(低相关区)序列集,以及任意长度最佳屏蔽二进序列偶与正交矩阵构成ZCZ序列集。利用这些构造方法,扩展了原有低/零低相关区存在的长度范围,扩大了序列集的容量,可以更好地满足工程应用的需要。     

广义相对差集偶与二元序列偶的研究

提出了一类新的区组设计——广义相对差集偶的概念,研究了广义相对差集偶的性质,给出了广义相对差集偶对应的二元序列偶的自相关函数,该函数具有脉冲函数的性质,在实际应用中可扩大最佳信号的可选范围,同时也为应用广义相对差集偶这种区组设计的方法研究最佳二元序列偶提供了理论依据。     

II型Z-优化二元互补序列对的构造

该文以长度为N(N为整数)的Golay互补对(GCP)为种子序列对，在种子序列对的3个选定位置中插入特定的码元，构造出长度为N+3的II型Z-优化2元Z-互补序列对(ZCP)。与已知同长度II型Z-优化2元Z-互补序列对相比，构造的新序列有更低的峰均包络功率比(PMEPR)。Z-互补序列对和Golay互补序列对都广泛应用于正交频分复用(OFDM)系统和码分多址(CDMA)系统等，但前者有更灵活的序列长度和更多的序列数量，更能满足应用的需求。     

屏蔽二元互补序列偶构造方法的研究

在分析和研究屏蔽二元互补序列偶性质的基础上,提出了几种屏蔽二元互补序列偶新的构造方法,这些新的构造方法进一步丰富和完善了屏蔽二元互补序列偶理论.研究表明,所提出的序列偶构造方法能够简单地产生出更多的屏蔽二元互补序列偶,可以为实际工程应用提供最佳信号设计.     

最佳二元阵列偶的惟一性问题研究

提出并解决了最佳二元阵列偶(PBAP)的惟一性问题，从理论上解决了PBAP在应用时的惟一接收问题。同时证明了当N=0(mod4)时存在PBAP(N)。     

On the structure of rate1/nconvolutional codes

We show what choice there is in assigning output digits to transitions of a binary rate1/ncode trellis so that the latter will correspond to a convolutional code. We then prove that in any ratefrac{1}{2}noncatastrophic code of constraint lengthupsiloneach binary sequence of length2j(1 leq j leq upsilon - 1)is associated with exactly2^{upsilon -j -1}distinct pathsjbranches long. As a consequence of the above properties nondegenerate codes with branch complementarity are fully determined by the topological relationship of the trellis transitions associated with output pairs 00. Finally, we derive a new upper bound on free distance of rate1/nconvolutional codes and use our results to determine the length of the largest input sequence that can conceivably result in an output whose weight is     

最佳屏蔽二进阵列偶构造方法研究

给出了四种构造最佳屏蔽二进阵列偶的方法,即最佳屏蔽二进阵列偶的周期乘法、半周期最佳屏蔽二进阵列偶的直积、最佳屏蔽二进序列偶与阵列偶间的折叠构造以及最佳屏蔽二进阵列偶之间的折叠构造。     

基于交织的二元及四元完备序列和序列偶的构造方法

基于交织技术,提出了三类二元及四元完备序列和序列偶的构造方法。分别利用二元完备序列、二元完备互补序列对和二元完备序列偶作为初始序列,通过合理设计带符号移位序列,基于交织获得了不同的二元及四元完备序列和序列偶。这些构造方法均可不断递归地进行,从而获得更多具有新参数的完备序列及完备序列偶。该方法通过引入带符号的移位序列,在一定程度上改善了目标序列的相关性能,为序列的构造提供了新的思路。     

差集偶与周期互补二元序列偶的研究

研究了差集偶，提出了多种差集偶的构造方法，并在此基础上提出了基于差集偶的周期互补二元序列偶的构造方法，可以方便地获得大量周期互补二元序列偶。     

基于分圆类的一类伪随机二进序列偶的构造方法研究

 本文把“分圆类”引入到序列偶的构造中,提出了一种伪随机序列偶构造的新方法——分圆类法. 利用分圆类法构造出差集偶,通过差集偶与伪随机序列偶的等价关系,进而构造出一类新的伪随机序列偶,此种序列具有很好的“0”、“1”平衡性和好的自相关度, 为应用差集偶这种区组设计的方法研究伪随机序列偶提供了新的理论依据.     

Periodic binary sequences with the "trinomial property"

Periodic binary sequences with the "trinomial property" are considered. Some necessary and sufficient conditions for "trinomial pairs" of a nonlinear sequence of period 2/sup n/-1 as well as classifications for trinomial pairs are derived. Complete searches for trinomial pairs of sequences have been completed for 3/spl les/n/spl les/17. We list them here for n/spl les/12.     

二元二值周期自相关序列偶的应用研究

该文提出了正交矩阵偶的概念,它是正交矩阵的一种扩展,尤其二元正交矩阵偶不受阶数应为2的幂次的限制。应用二元二值周期自相关序列偶,提出了一种构造二元正交矩阵偶的方法和一种构造正交序列偶集的方法,还提出了一种利用正交矩阵偶或正交矩阵结合正交序列偶集交织构造适于准同步码分多址通信系统应用的二元零相关区序列偶集的新方法,通过对二元二值周期自相关序列偶的选择可使构造的零相关区序列偶集获得高的能量效率,并可使集合的序列偶数量,零相关区长度及序列偶长度参数接近最大理论限。     

互补二进阵列偶的理论研究

具有良好非循环相关特性的序列中,互补序列最具有代表性。提出了一种新的非循环相关信号,即互补二进阵列偶。给出了定义,并研究了其变换性质。同时为了减少搜索范围,提高计算机搜索效率,研究给出了一些互补二进阵列偶的组合允许条件。互补二进阵列偶理论拓宽了互补序列的研究范围,有很好的工程应用背景。     

零相关区屏蔽四元周期互补序列偶集设计研究

该文提出一种零相关区(ZCZ)屏蔽四元周期互补序列偶集的设计方法。基于最佳二元屏蔽序列偶和正交矩阵构成ZCZ屏蔽序列偶集,经过交织迭代得到ZCZ屏蔽周期互补序列偶集,进而利用新型逆Gray映射构造了ZCZ屏蔽四元周期互补序列偶集。结果达到理论界限,进一步拓展了扩频序列的可选空间。     

A class of nonlinear error correcting codes based upon interleaved two-level sequences (Corresp.)

In this correspondence, we consider nonlinear binary error-correcting codes based upon then-fold interleaving of a periodic binary sequence of lengthLwith out-of-phase (normalized) autocorrelation-1/L. Examples of binary sequences with such out-of-phase autocorrelation (termed two-level sequences) are: 1) maximal-length linear shift-register footnote[1]{sequences}, 2) twin-prime footnote[2]{sequences}, 3) quadratic residue footnote[3]{sequences}, and 4) Hall foonote[4]{sequences}.     

New Design of Low-Correlation Zone Sequence Sets

In this paper, we present several construction methods for low-correlation zone (LCZ) sequence sets. First, we propose a design scheme for binary LCZ sequence sets with parameters (2ⁿ⁺¹-2,M,L,2). In this scheme, we can freely set the LCZ length L and the resulting LCZ sequence sets have the size M, which is almost optimal with respect to Tang, Fan, and Matsufuji bound. Second, given a q-ary LCZ sequence set with parameters (N,M,L,epsi) and even q, we construct another q-ary LCZ sequence set with parameters (2N,2M,L,2epsi) or (2N,2M,L-1,2epsi). Especially, the new set with parameters (2N,2M,L,2) can be optimal in terms of the set size if a q-ary optimal LCZ sequence set with parameters (N,M,L,1) is used