伪码调相与正弦调频复合探测信号处理技术研究

【作者】 任娜；

【导师】 赵惠昌；

【作者基本信息】 南京理工大学 ， 通信与信息系统， 2010， 硕士

【摘要】 伪码调相与正弦调频复合信号既具有伪码的极低的截获概率和良好的抗干扰能力又具有正弦调频的抑制近距离泄漏和降低多普勒敏感的特点,伪码调相与正弦调频复合探测系统利用回波信号中的伪码进行相关处理实现对目标的定距,利用回波信号混频后的差频信号中提取的多普勒信号实现对目标的测速。本文先分析了伪码调相信号和正弦调频信号的特性,然后重点分析了伪码调相和正弦调频复合探测系统的信号处理过程。在复合探测系统工作原理的基础上,分析了复合信号的时域和频域特性,接着分析了复合信号模糊函数的特点,并讨论了复合信号的参数选择问题,在参数选择合理的基础上,对整个复合系统的信号处理过程进行了仿真,分别结合时域和频谱图分析了信号处理每一步的特性,并从回波信号中提取出目标的距离和速度信息。最后通过计算接收机的增益讨论了复合探测系统对几种形式的噪声信号的抗干扰性能,并给出了复合信号的优越性,证实了伪码调相与正弦调频复合探测系统的可实现性。更多还原

【Abstract】 The serrated signal of pseudo-code phase modulation and sine frequency modulation has both low acquisition probability and good anti-jamming ability of the pseudo-code and the characteristics of suppressing the close divulgence and reducing the doppler sensitivity which is the characteristics of sine frequency modulation, the complex detection system of pseudo-code phase modulation and sinusoidal frequency modulation decides the distance using the related processing of pseudo-code in echo signal and measures the target’s speed by extracting the doppler signal in the difference frequency signal of the sine frequency modulation in echo signal.This thesis first analyzes the characteristics of pseudo-code phase modulation signal and sinusoidal frequency modulation signal, then analyzes the signal processings on the complex detection system of pseudo-code and sine frequency modulation. This thesis analyzes the complex signal’s characteristics in time domain and in frequency domain based on the principles of the complex detection system, and analyzes the characteristics about ambiguity functions of the composite signal, followed by a discussion of parameters’ choice about the composite signal, and simulates the whole signal processings of the complex system based on the choice of the parameters, analyzes each step of the signal processing combined with the pictures in time domain and in the form of spectrum, and the system can extract the information about the target’s distance and speed from the echoes. Finally, this thesis discusses the anti-jamming performance of the composite signal by calculating the gain of the receiver about noise, frequency-modulation noise and amplitude-modulation noise, and gives the advantages of the complex detection system, this thesis confirms the realizability of the complex detection system.更多还原