关键词: 立方调频信号, 参数估计, 相参积累, 高阶模糊函数, 相参积累三阶自相关函数

Abstract:

Aiming at the parameter estimation problem of Cubic Frequency Modulated（CFM） signals, a parameter estimation method based on High order Ambiguity Function（HAF） and Coherently Integrated Trilinear Autocorrelation Function（CITAF） is proposed in this paper. First, the method demodulates CFM signals to Quadratic Frequency Modulated（QFM） signals via the HAF, and then the CITAF is applied to realize the parameter estimation of QFM signals. The CITAF can accomplish two-dimensional signal energy integration coherently both in time and lag-time domains, and its implementation can be accomplished through complex multiplication, Fourier transform, and addition operations. Therefore, the proposed method can improve the resolution and anti-noise ability of parameter estimation, and its computational cost is low. The effectiveness and performance superiority of the proposed method have been verified through experimental results.

Key words: cubic frequency modulated signals, parameter estimation, coherent integration, High order Ambiguity Function（HAF）, Coherently Integrated Trilinear Autocorrelation Function（CITAF）