基于上采样和高阶Hermite插值滤波器组的超宽带数字波束形成技术研究

直接延时(DTD)补偿是超宽带(UWB)信号波束形成的有效方法，其数字波束形成(DBF)的效果与DTD滤波器的频率特性有直接的关系。在分析现有Lagrange插值滤波器存在问题的基础上，研究了利用多路上采样和高阶Hermite插值滤波器结合实现 UWB信号DTD的方法，以及通过多路延时补偿实现UWB信号DBF的技术。提出了一种结构简单的固定系数插值DTD补偿滤波器组的DBF实现方法。理论分析与仿真结果表明，与Lagrange插值法相比，该方法不仅实时性更好，而且在采样率低于Nyquist率时能更好地恢复原始UWB信号，其UWB信号DBF性能明显优于传统方法。

Research on UWBDBF Using Direct Time Delay Compensation Based on Up-sampling Technology and High-order Hermite Interpolation Filter Sets

Direct time delay (DTD) compensation is an effective method for beamforming of ultra-wideband (UWB) signal. The digital beam-forming (DBF) performance is directly related to the frequency response of the DTD filter. Based on the analysis of problems existing in Lagrange interpolation filter, a novel method utilizing interpolation filter sets with fixed coefficients is presented to implement DBF. High-order Hermite interpolation filter sets with simple structure combing multi-channel up-sampling technology are applied to DTD and the DBF of UWB signals is achieved by multi-channel delay compensation. Theoretical analysis and simulation results show that the proposed method is featured by a more accurate recovery of UWB signals when sampling rate is less than the Nyquist rate. It has a better real-time and an obviously superior DBF performance compared to the traditional methods such as Lagrange.