摘要
针对基于Radon-Ambiguity变换(RAT)和分数阶Fourier变换(FrFT)的对称三角线性调频(STLFM)信号参数估计算法运算量较大的问题,在分析RAT变换估计调频斜率和STLFM信号模糊函数特征基础上提出了一种基于模糊函数(AF)切片和FrFT的STLFM信号参数估计新算法。该算法首先通过对观测信号固定时延点AF切片的计算估计出调频斜率,然后得到相应的FrFT最优变换阶数,最后利用两次FrFT估计出STLFM信号的调频带宽、调频周期和中心频率等参数。整个算法只需3次FFT的计算量即可估计出STLFM信号的所有参数。仿真实验表明了该算法能实现STLFM信号参数的快速有效估计。
In order to reduce the computation complexity of parameter estimation for STLFM signals, a new algorithm based on Ambiguity Function slice and Fractional Fourier Transform is presented by analyzing frequency rate estimation based on RAT and characters of ambiguity function. Firstly, the frequency rate is estimated through one AF slice at fixed time-delay of observed signals, and then the best order of FrFT is obtained. Finally, other parameters, including frequency modulation band- width, frequency modulation cycle and center frequency, are estimated by twice FrFT. The whole processing just needs three times FFT computation complexity and can estimate all the STLFM signal parameters. Simulation results show that the algorithm can estimate the parameters of chirp signals quickly and effectively.
出处
《信息工程大学学报》
2013年第1期84-90,共7页
Journal of Information Engineering University
关键词
对称三角线性调频
模糊函数
分数阶FOURIER变换
信号检测
参数估计
symmetrical triangle linear frequency modulation
ambiguity function
fractional Fouriertransform
signal detection
parameter estimation
