论述了未知循环频率的周期平稳信号循环双谱的估计方法；研究了在循环双谱的循环累积量计算中涉及变量的简化存储方法，提出了该变量矩阵是对称阵，通过算法可以三角阵的元素来表述，克服了循环双谱传统估计方法计算量较大的缺陷，提高了运算效率；提出了循环双谱对调相故障信号的分析能力，以及对加性噪声的处理能力，仿真并验证了该方法的有效性，并将其应用于旋转机械状态分析。

The way of computing the cyclic cumulant of cyclostationary signal of unknown cyclic frequency is studied, the nth-order lag product of the input cyclostationary signal is analyzed and the way of decreasing the used EMS memory and the time of compute is studied. By the analysis of simulation testing data of phase modulation signal, the cyclic bispectrum is showed to be effective. And the cyclic bispectrum is used to analysis of the industrial vibration data of the rotating machine and proves to be effective.