基于四阶累积量的直扩信号检测方法

The Detection Methods of DSSS Based on the Fourth-Order Cumulants

根据高阶统计量可以抑制任何高斯噪声的特性,该文研究了利用四阶累积量的DS-SS/QP-SK直扩信号的检测方法,提出了一类基于四阶累积量C4x(0,0,0)、C4x(τ,τ,τ)、C4x(0,τ,τ)和C4x(0,0,τ)的DS-SS/QPSK信号检测方法。仿真结果表明,利用C4x(0,τ,τ)的检测方法性能最好,在信噪比为-5dB时,其检测概率仍可达50%以上。这类方法由于没有引入大规模的矩阵运算,运算量小,易于实现,具有一定的实际意义。

According to the fact that higher order cumulants can suppress any Gaussian noise, this paper studies how to use the fourth - order cumulant to detect the DS - SS/QPSK, and four kinds of detection methods of DSSS/ QPSK based on the fourth - order cumulants C4x（0,0,0） ,C4x（τ,τ,τ） ,C4x（0,τ,τ） and C4τ（0,0,τ） are proposed. The experimental results show that the detection performance of the method using C4x（0,τ,τ） is the best, and its detection probability is above 50% at SNR - 5dB. Because they don＇ t involve extensive matrix operations, their computation complexity is low, and they are easy to implement.