中文摘要：

直接序列扩频技术具有强抗干扰能力，高保密性等优点，在军事和民用通信等领域有广泛的应用．但反过来在复杂噪声环境中对其进行检测和参数估计是一个非常困难的课题．本文利用循环谱理论，根据直扩信号和高斯噪声在循环平稳性上的差异来实现在循环频率轴上对二者的检测和参数估计．实验仿真结果表明，此方法在低信噪比条件下具有很好的效果．

英文摘要：

The spread spectrum technology has been used widely in fields such as military and civil communications because of its strong anti-interference, excellent secrecy. Thus it is very difficult to detect DSSS and estimate its parameters. Noticing that the direct sequence spread signal and Gaussian noise are different in cyclostation based on spectrum theory, so this paper presents a method that makes use of cyclic spectrum correlation technology to detect DSSS and estimate its parameters. The simulation results show that the algorithm is effective.