基于时频对消的跳频信号盲检测算法  

A BLIND DETECTION ALGORITHM OF FREQUENCY HOPPING SIGNAL BASED ON TIME-FREQUENCY CANCELLATION

作　　者：王琳[1] 赵知劲[1,2] 尚俊娜[1] 王李军[2] Wang Lin;Zhao Zhijin;Shang Junna;Wang Lijun(School of Communication Engineering,Hangzhou Dianzi University,Hangzhou 310018,Zhejiang,China;State Key Lab of Information Control Technology in Communication System,No.36 Research Institute of China Electronics Technology Group Corporation,Jiaxing 314001,Zhejiang,China)

机构地区：[1]杭州电子科技大学通信工程学院,浙江杭州310018 [2]中国电子科技集团第36研究所通信系统信息控制技术国家级重点实验室,浙江嘉兴314001

出　　处：《计算机应用与软件》2023年第4期217-221,256,共6页Computer Applications and Software

基　　金：国家自然科学基金项目(U19B2016)。

摘　　要：针对低信噪比下跳频信号检测概率低问题,提出一种基于时频对消的跳频信号盲检测算法。根据跳频信号与定频信号的不同时频特性,利用短时傅里叶变换,理论上分析推导了跳频信号、定频信号和高斯白噪声的时频对消比,根据时频对消比差异性,得到三元假设检验规则;针对实际脉冲噪声背景,利用分数低阶短时傅里叶变换代替短时傅里叶变换估计得到时频对消比,实现了未知先验信息条件下跳频和定频信号的同步检测。计算机仿真结果表明,当跳频信号检测概率高于0.8时,相比于功率谱对消法,该算法改善信噪比大于1.5 dB以上。该算法抗噪声功率不确定性较强,实现简单。Aimed at the problem of low probability of frequency hopping signal detection under low signal-to-noise ratio,a blind detection algorithm of frequency hopping signal based on time-frequency cancellation is proposed.According to the characteristics difference in time-frequency domain between frequency hopping signals and fixed-frequency signals,the short-time Fourier transform was used,and the time-frequency cancellation ratio of frequency-hopping signals,fixed-frequency signals and white Gaussian noise were theoretically analyzed and derived respectively.According to the difference of time-frequency cancellation ratio,the ternary hypothesis test rule was obtained.The fractional low-order short-time Fourier transform was substituted for the short-time Fourier transform to obtain the time-frequency cancellation ratio,which realized the synchronous detection of frequency hopping and fixed-frequency signals under the condition of unknown prior information in actual pulse noise background.The computer simulation results show that when the probability of frequency hopping signal detection is higher than 0.8,the SNR of this algorithm is improved above 1.5 dB compared with the power spectrum cancellation method.Its anti-noise power uncertainty is relatively strong,and its implementation is simple.

关 键 词：跳频信号 检测 时频对消 短时傅里叶变换 功率谱 

分 类 号：TP391.99[自动化与计算机技术—计算机应用技术] TN914.41[自动化与计算机技术—计算机科学与技术]