基于多项式插值的定时恢复内插算法

经典的数字调相信号的定时恢复算法中,接收端定时误差矫正主要采用对内插滤波器逼近的方法来实现,这往往会将插值误差通过滤波后平均到定时输出中.提出一种基于时域多项式插值的定时误差矫正算法,通过选取最佳定时位置附近的采样点来构成插值模型,根据Lagrange插值算法或Newton插值算法得出表示信号时域波形的连续多项式函数解析式,取出该最佳定时点处的函数值作为定时恢复的输出,针对输出表达式的多项式特性以及差商和差分的关系对其进行类似Farrow结构的改进,以降低计算复杂度.对该算法在高斯信道下进行仿真,结果表明,所提出的时域样点插值法比内插滤波器逼近法的星座点收敛得更小,且收敛速度更快.

Interpolating algorithm based on polynomial interpolation in timing recovery

Doppler Power Spectral reflects the performance of the wireless channel. It has certain effects on modulation and demodulation of the receiver. With the development of MIMO(Multiple-Input Multiple-Output)systems, the traditional model is no longer applicable to analyze the MIMO channel. We need better analysis and forecast Doppler Power Spectral of MIMO systems. In this paper, based on the 3GPP(The 3rd Generation Partner Project)spatial channel model whose distribution of Power Azimuth Spectrum is Laplace distribution, we analyzed and deduced Doppler Power Spectral. We proposed a statistical method of Doppler power spectrum after carrying out the analysis of the Spatial-temporal correlation and counted the numerical results by means of configuring a special transmitter signal in MATLAB simulation platform. Experimental results showed that: Doppler Power Spectral of the MIMO channel is determined not only by the moving speed of the user terminal and the central carrier, but also the distribution of its incident angle which plays a decisive influence.