基于噪声功率估计的抗窄带干扰接收机自适应PN码捕获技术

Adaptive PN code Acquisition Technique Based on Noise Power Estimation In Narrowband Interference Suppression Receiver

在存在强窄带干扰条件下,正确实现伪码捕获是抗干扰接收机的关键技术之一。变换域干扰检测与PN码捕获判决都需要估计接收机背景噪声功率,本文在变换域谱线幅度平方服从指数分布假设下,利用中位数估计理论对存在窄带干扰接收信号的背景噪声功率进行估计,实现干扰检测门限和PN码捕获判决门限的自适应设置。仿真结果表明,文中设计的检测装置可实现强窄带干扰、大动态范围接收机PN码的正确捕获。

The problem of PN code acquisition is the key technique in DSSS receiver when there are narrowband interferences in the received signal. The estimation of noise power is needed by both transform domain interference detection and PN code acquisition detection. This paper proposes a method of noise power estimation based on exponential distribution and sample median.. The PN code acquisition threshold is designed from the constant false alarm probability rule. The simulation results prove that the detection device can acquire the PN code in narrowband interference and large dynamic range received signal conditions.