基于组合CPF变换的混合低阶相位调制信号参数估计  

Parameters Estimation for Mixed Signals of Low-level Frequency-modulated Signals with a Combinational Cubic Phase Function Transformation

作　　者：王小青[1] 曹建蜀[1] 

机构地区：[1]电子科技大学电子科学技术研究院,成都611731

出　　处：《信号处理》2015年第11期1518-1522,共5页Journal of Signal Processing

摘　　要：由线性调频信号(LFM)、三阶多项式相位调制信号(QFM)混合而成的信号在三阶相位函数随机变换(RCT算法)下可实现相位参数估计,但是当信号参数相近时算法存在峰值干扰现象。针对此情况,提出一种组合CPF变换,首先通过ICPF算法估计LFM信号相位参数,然后利用估计得到的参数重构LFM信号,以消去混合信号中的LFM信号,再通过RCT算法估计剩余QFM信号的相位参数。仿真实验表明,相较于传统RCT算法,组合CPF变换方法能够抑制信号间干扰,对混合信号具有更好的估计精度。In this paper,a combinational cubic phase function（ CCPF） transformation is introduced for the estimation and detection of low-level frequency-modulated signals. The CCPF transformation extends the standard cubic phase function（ CPF） by studying random cubic phase function transform（ RCT） and Integrated cubic phase function（ ICPF） to handle cases involving low signal-to-noise ratio（ SNR） and mixed signals interference of chirp signal（ LFM） and quadratic frequency modulation signal（ QFM） when parameters of each are approaching. The course of CCPF commonly includes two stages： firstly,realizing LFM reconstruction with ICPF; then estimating parameters of QFM when elimination LFM from mixed-signals is finished. The asymptotic mean squared error（ MSE） of an CCPF-based estimator is verified by computer simulation. Comparison with traditional RCT is also included,which shows that the CCPF serves as a good candidate for mixed signal analysis.

关 键 词：参数估计 三阶多项式相位调制信号 线性调频信号 

分 类 号：TN957[电子电信—信号与信息处理]