序列移相跳频组网分析与设计

为了提高跳频网络的通信效率,提出了利用同一跳频序列的相位差异实现跳频组网的方案。首先,以m序列为例分析了跳频序列移相的原理和实现方法;然后,将管理通道和数据通道相分离进行序列移相跳频组网设计和网络协议规划,给出了跳频序列的移相值优化方案。该方案具有网络管理灵活方便、通信效率高、抗干扰能力强等特点。仿真结果表明,序列移相跳频组网的网间干扰与异步组网相比有较大幅度改善。

VLSI测试中移相伪随机序列的设计

为了用较少的硬件和测试时间开销获得对被测电路较高的故障覆盖,提出了一种数字集成电路测试中多扫描链的配置方法。该方法基于最大周期的线性反馈移位寄存器LFSR生成的m序列的移位可加性,可使较短长度的LFSR驱动多个扫描链;为了减小LFSR生成序列的互相关性,利用LFSR与其对偶LFSR间的关系,提出了基于逻辑仿真的移相器的快速设计方法,实验结果验证了该方法的有效性,对VLSI的内测试和外测试皆适用。

抗跟踪干扰跳频网络设计方法研究

跟踪干扰是跳频通信的克星,合理科学的组网是对抗跟踪干扰的有效手段之一。提出了一种基于跳频序列的相位差异进行跳频组网的方案,进行了方案可行性分析、网络协议规划和组网过程设计。在明确了跟踪干扰实施条件的基础上,从网台分选概率和跟踪干扰对网络的影响等方面分析网络的抗跟踪干扰特性。仿真结果表明,该跳频网络具有较低的跟踪干扰概率,能够有效的对抗敌方的跟踪干扰。

AUTOCORRELATIONS OF l-SEQUENCES WITH CERTAIN SHIFTS

In this paper, the autocorrelations of maximal period Feedback with Carry Shift Register sequences （l-sequences） are discussed. For an l-sequence a with connection integer q = p^e（e ≥ 2） and period T = p^t-1（p- 1）, and for any integer i, 1 ≤ i ≤ e/2, by calculating the number of certain sets, it is shown that the autocorrelation of a with shift τ= kT/2p^i is Ca（τ） =（-1）^k-1 T/p^2i-1, where 1 ≤ k ≤ 2p^i - 1, and gcd（k,2p^i） = 1. This result shows there do exist some shifts such that the autocorrelations of l-sequences are high although most autocorrelations are low. Such result also holds for the decimations of l-sequences.

High efficiency spreading spectrum modulation using double orthogonal complex sequences

This paper presents a novel scheme of high efficiency spreading spectrum modulation using double orthogonal complex sequences （DoCS）. In this scheme, input data bit-stream is split into many groups with length M. Each group is then mapped into a word of width M and then utihzed to select one sequence from 2u-2 DoCS sequences each with length L. After that, the selected sequence is modulated on carrier in quadrature phase shift keying （QPSK） mode. In addition, a new method named forward phase correction （FPC） is put forward for carrier recovery. Theoretical analysis and bit-error-ratio（BER） experiment results indicate that the proposed scheme has better performance than the conventional direct sequence spread spectrum（DSSS） scheme both in bandwidth efficiency and processing gain of the receiver.

FAMILIES OF p-ARY SEQUENCES WITH LOW CORRELATION AND LARGE LINEAR COMPLEXITY

This paper generalizes a method of generating shift sequences in the interleaved construction proposed by Gong.With the new shift sequences,some new families of p-ary sequences with desired properties can be obtained.A lower bound on the number of new families of binary sequences is also established.

A generic construction of low correlation zone sequences based on interleaved technique

Low correlation zone (LCZ) sequences are useful in quasi-synchronous code-division multiple access (QS-CDMA) communication systems. In this paper, a generic construction of LCZ sequences based on inter-leaved technique is investigated. Firstly, the shift sequence is shown to correspond to two-tuple balanced d-form function essentially, which results in new shift sequence. Secondly, an optimal design of p2-ary sequences over the integer residue class ring Zp2 is proposed, which improves the previous construction when p is an odd prime.