实复转换式衰减信号参数估计算法  

Real-to-complex-transformation parameter estimation algorithm for damped real-value sinusoidal signals

作　　者：陈鹏 涂亚庆 沈艳林[2] 牟泽龙 李明 CHEN Peng;TU Yaqing;SHEN Yanlin;MOU Zelong;LI Ming(Military Logistics Department,Army Logistics University of PLA,Chongqing 401311,China;Department of Equipment Support,Logistics College of CAPF,Tianjin 300309,China)

机构地区：[1]陆军勤务学院军事物流系,重庆401311 [2]武警后勤学院装备保障系,天津300309

出　　处：《振动与冲击》2020年第14期53-58,共6页Journal of Vibration and Shock

基　　金：国家自然科学基金(61871402,61601493);国家重点研发计划(2018YFB2003900);天津市自然科学基金(18JCQNJC01400);重庆市研究生科研创新项目(CYB18129);武警后勤学院博士启动资金项目(WHB201707)。

摘　　要：为抑制衰减实信号中负频率成分对参数估计的影响,提出一种实复转换式参数估计算法。预估计采样信号频谱能量最大值点的索引值;构造只含有负频率成分的参考信号,并将采样信号和参考信号相减实现实复转换,以抑制负频率频谱泄漏的影响;利用频谱两点插值算法得到频率偏差、衰减因子和复幅值的粗估计值,并重新生成参考信号和复信号;通过迭代计算得到精确的频率、衰减因子、初幅值和初相位估计值。以频率估计为例的仿真实验结果表明:所提算法可有效地抑制负频率频谱泄漏的影响,提高中高信噪比条件下的频率估计精度,特别是信号频率较低时的频率估计精度,提升了频率估计的综合性能。此外,在科氏流量计中进行了实测实验,检验了所提算法的有效性。To suppress the influence of negative frequency component of a damped real-value sinusoidal signal on its parameter estimation, a real-to-complex-transformation parameter estimation algorithm was proposed. First, the index number bin at the point with the highest energy magnitude of the sampled signal spectrum was pre-estimated. A reference signal only containsing the negative frequency component was constructed, and the real-value signal was converted into a complex-value signal by subtracting the reference signal form the sampled signal to suppress the spectrum leakage influence of the negative frequency component. Then, the frequency offset, damping factor and complex amplitude were coarsely estimated by a two-point spectrum interpolation algorithm, on this basis, the reference signal and the complex signal were rebuilt. Finally, the signal parameters, i.e. the frequency, damping factor, initial amplitude and initial phase were obtained by using an iterative procedure. The results of simulation experiments for frequency estimation indicate that the proposed method can eliminate the influence of negative frequency component, improve estimation accuracy under medium or high SNRs, especially, in the low signal frequency band, which improves the overall performance of the frequency estimation. Measurement experiments were performed on a Coriolis mass flowmeter, and the efficacy of the proposed method was validated.

关 键 词：实复转换 参数估计 负频率成分 频谱泄漏 衰减实信号 科氏流量计 

分 类 号：TH814[机械工程—仪器科学与技术]