样本含噪情况下相关处理增益损失分析

Analysis of Co-Correlation Process Gain Loss by Using Noised Reference Signal

利用互相关处理对辐射源信号进行检测是提高侦收系统灵敏度的一种有效手段。通常情况下,互相关的样本信号是通过天线接收辐射源的直达信号得到的,因此样本信号不可避免的会含有噪声。尤其是当信号功率较为微弱的情况下,样本的信噪比会较差。使用含有噪声的样本信号进行互相关处理时,样本中的噪声会抬高相关后的噪声基底,导致处理增益下降。通过理论分析得出了样本含噪情况下的相关处理增益,以及相对无噪理想样本情况下相关处理增益损失和样本信噪比之间的关系,并通过计算机仿真,证实了这个结论的正确性。

Using Co-Correlation to detect emitter is a very effective method used in electronic reconnaissance. Reference signal used in Co-Correlation is often been obtained through receiving direct signal from emitter. So it is inescapable that noise will be mixed into reference signal, especially when signal power is weak, and the signal-to-noise ratio will be low. When noised reference signal is used in Co-Correlation, noise contained in reference will raise noise floor of Co-Correlation output, and then Process Gain is dropped. In this paper, Co-Correlation Process Gain Loss due to noise contained in reference signal is analyzed, and the expression of Process Gain Loss is also given. Computer simulation is presented, which proves that the conclusion is correct.