基于频域插值滤波的跳频信号高时频分辨率测量方法  

High temporal frequency resolution STFT algorithm for frequency hopping frequency word extraction application

作　　者：吕新 程翰 张一嘉 Lü Xin;Cheng Han;Zhang Yijia(Zhejiang Sci-Tech University,Hangzhou 310018,Zhejiang,China;No.8511 Research Institute of CASIC,Nanjing 210007,Jiangsu,China)

机构地区：[1]浙江理工大学信息学院,浙江杭州310018 [2]中国航天科工集团8511研究所,江苏南京210007

出　　处：《航天电子对抗》2022年第3期17-21,共5页Aerospace Electronic Warfare

摘　　要：传统网台分选多采用固定滑动窗短时傅里叶变换(STFT)方法,无法摆脱频率间隔与时间间隔互相制约的弊端,导致跳频频率字到达时间估计不准,网台分选效果不理想。研究了基于频谱线性插值的高时间分辨率STFT方法。通过变窗宽、时域频偏插值方法来改进STFT运算,提出基于频域插值滤波的STFT方法。在增加适当运算量的情况下,保持频率分辨率不变,将时间分辨率提高了一倍。经过某实际网台数据仿真验证,该方法在不同信噪比下均有较小的误差值,提高了频率字提取的精度,为网台分选打下基础。The traditional network station sorting mostly adopts the fixed sliding window STFT algorithm,which cannot get rid of the disadvantage that the frequency interval and the time interval are mutually constrained,resulting in the inaccurate estimation of the hopping frequency rate word arrival time and the unsatisfactory network station sorting effect.A high time resolution Short Time Fourier Transform(STFT)method based on linear interpolation of the frequency spectrum is investigated.The STFT operation is improved by a variable window width,time-domain frequency bias interpolation method,and the STFT method based on frequency domain linear interpolation is proposed.The time resolution is doubled while keeping the frequency resolution unchanged with an increase in the appropriate amount of operations.After an actual network station data simulation verification,the algorithm has a small error value under different signal-to-noise ratios,which improves the accuracy of frequency word extraction and lays a foundation for network station binning.

关 键 词：短时傅里叶变换 线性插值 跳频频率字 通信侦察 网台分选 

分 类 号：TN971.1[电子电信—信号与信息处理]