关键词: 乘积高阶模糊函数, 交叉项, 多分量多项式相位信号, 参数估计

Abstract: Though originally proposed for analyzing multi-component polynomial phase signal（mc-PPS），the Product High-order Ambiguity Function（PHAF） can not be used to estimate mc-PPS directly for its validity is degraded by the interference terms of the mc-PPS.Iterative filtering is an efficient method to suppress interference terms but is troubled by error propagation between components.The Relaxation method（RELAX） is capable of controlling error propagation in sequential estimation by recursive iteration.In this paper，a new method called iterative-RELAX PHAF is proposed by combining iterative filtering and RELAX.Analyzing the performance of the estimated signal variable parameter shows that the improved version of PHAF enjoys better robustness，provides better precision，reduces the blind area and has low threshold of Signal to Noise Ratio（SNR）.The performance of the new method is verified by simulations with mc-PPS.

Key words: product high-order ambiguity function, interference term, multi-component polynomial phase signal, parameter estimation