改进的DFT插值频率估计算法及其DSP实现

摘要

This paper proposes an improved frequency estimation algorithm using discrete Fourier transform (DFT) interpolation based on the Quinn algorithm and iterative interpolation algorithm (A&M algorithm).The proposed algorithm first uses a frequency error estimated by the Quinn algorithm as the initial error value of the iterative estimation algorithm.Then frequency error is estimated accurately by the iteration algorithm.The algorithm can effectively reduce the number of iterations and guarantee the precision of estimation results,thus improving the computational efficiency.To enhance the efficiency of the algorithm on the DSP processor,this paper also proposes an optimization method for the implementation of the algorithm on the DSP processor,which is helpful for the application of the algorithm in real time.The simulation results show that the proposed algorithm can increase the frequency estimation accuracy,and the efficiency of real-time computation with good anti-noise performance.%在Quinn算法和插值迭代算法(A&M算法)的基础上,提出了一种改进的离散傅里叶变换(Discrete Fourier transform,DFT)插值频率估计算法.该算法首先通过Quinn算法估计出1个频率误差作为迭代估计算法的误差初值,然后用迭代算法精确估计频率误差.改进后的算法可以有效减少迭代次数,因此同时具有Quinn算法的高效率和A&M插值迭代算法的高精度.为了提高算法在DSP处理器上的运行效率,本文还对算法在DSP上的实现提出了一种优化方法,有利于该算法的卖时性应用.仿真结果表明该算法在频率估计精度、实时运算效率以及对噪声的抗干扰性能上均获得了提升.