摘 要：被動探測的關鍵技術之一就是通過有效的信號處理方法提取出多接收器的時間差，而確定時差最基本的方法是進行信號相關以獲得估計信息，相關算法雖然計算過程簡單，但是算法對信號和噪聲頻譜特性要求比較高。基于希爾伯特變換的時延估計是廣義相關時延估計方法的拓展，把相關函數的對稱性由偶函數轉化成奇函數，將相關法中對峰值的檢測轉化為對過零點的檢測。通過對兩種算法的誤差比較分析，信號的截至頻率越高，希爾伯特變換法的均方誤差與基本相關法的均方誤差相差越明顯，估計誤差越理想，證明Hilbert算法的優越性。
關鍵詞：Hilbert；時延估計；誤差分析；相關算法
文獻標志碼：A 文章編號：1674-5124（2015）12-0014-03
Error analysis of TDE based on correlation Hilbert transform
WANG Feng， LIU Pengyuan， LI Bing
（Foth Department，Ordnance Engineering College，Shijiazhuang 050003，China）
Abstract: Passive detection has the advantages of anti-reconnaissance， strong anti-jamming and concealment. It has become an important direction to raise the capacity of electronic countermeasures. One of the key technologies for passive detection is to extract the time lag through effective signal processing. Relevant method is the most basic information to estimate the time difference. It is the basic theory of all correlative time-delay estimation (TDE) algorithms. Calculation correlation method is simple. But satisfactory results cannot be achieved if the spectrum characteristics of signal and noise are not ideal. Time delay estimation based on Hilbert transform is the expansion of the generalized correlation time-delay estimation method which changes the correlation function from accidental symmetry into odd symmetry. Detecting correlation peak is converted into zero crossing detection. After comparing the error of the two kinds of methods， the higher the cutoff frequency is the more obvious when the differences between the mean squared errors of the two methods are larger. In other words， the estimate is more precise.
Keywords: Hilbert； time-delay estimation； error analyzing； correlation algorithms
