研究伪码复合体制引信的抗干扰性能对这类体制引信的发展乃至应用都具有重要的理论指导意义。文章以信干比增益作为衡量标准来研究伪码调相与正弦调频复合引信抗噪声调频干扰性能。首先介绍了该复合引信的工作原理，详细推导了存在噪声调频干扰时复合引信接收机的总信干比增益，分析了n阶贝塞尔函数、多普勒频率、伪码序列周期、码元宽度、瞄准误差对其抗干扰性能的影响，分析结果为提高该引信的抗干扰性能提供了重要理论依据。

Development and application of pseudo-random code combined fuze can be guided in theory by researching its anti-jamming performance. The anti-noise FM jamming performance of pseudo-random code phase modulation and sine FM combined fuze is analyzed based on the criterion of signal to jamming ratioin (SJR) gain in this paper. First, the principle of the combined fuze was introduced, and its overall SJR gain is reduced in detail under the noise FM jamming, then, the factors affecting its anti-noise FM jamming performance were analyzed, such as the nth order Bessel function of the first kind, Doppler frequency, pseudo-random code period, pulse width, and spot error. The results provide the important theoretic foundation for the improvement on anti-noise FM jamming performance of the combined fuze. At the same time, the studying method put forward in this paper may be used as the reference for analyzing anti-jamming performance of other type of fuzes.