基于多段分频等长信号融合的频率估计方法

多段采样信号十分常见，对其进行信息融合能有效提高信号处理的精度，尤其适用于低信噪比、被测频率持续时间短的情况。为提高多段采样信号频率估计的精度和扩展已有方法的适用范围，给出一种多段分频等长信号融合方法。在该方法中，因各段信号的被测频率不等，故生成频域分析参数矩阵以实现同频化效果；因同频化后各段信号之间仍然相位不连续，故设计相位差补偿因子矩阵以达到相位连续信号的效果；因相位差补偿因子矩阵包含未知参数，故生成搜索频率序列以用于实际计算并得到具有特定形式的功率谱矩阵。为验证方法的正确性，给出了数学证明。针对多种应用环境状态进行了仿真实验，结果表明该方法具有普适性，抗噪性好，频率估计精度比现有方法有较大提高。

Approach of frequency estimation based on information fusion among multi-section signals with same length and known frequency-ratio

Multi-section sampled signals is a kind of common signal,and information fusion among them can increase precision of signal process obviously,especially under the condition of low SNR and short duration of measured frequency.To increase precision of frequency estimation for multi-section signals and extend applicable range of existing methods,a fusion method of multi-section signals with the same length and known frequency-ratio is proposed.In the method,for unequal measured frequencies of different sections,generate the parameter matrix for frequency-domain analysis to carry out frequency normalization treatment.For phase discontinuity among different sections even after frequency normalization,design phase-difference compensating factor matrix to obtain frequency spectrum as well as phase-continuous signal.For unknown parameters in the phase-difference compensating factor matrix,generate search frequency array for actual computation and obtain frequency spectrum amplitude matrix with certain form.To prove validity of the algorithm,mathematical justification is provided.Simulated experiments with different application environment parameters are carried out.They show that the algorithm is true of any type of multi-section signals with the same length and known frequency-ratio.It has good noise immunity and its precision of frequency estimation is much higher than that of existing methods.