接收阵列天线DBF技术研究

【作者】 赵军；

【导师】 是湘全；

【作者基本信息】 南京理工大学 ， 通信与信息系统， 2003， 硕士

【摘要】 在车辆应用条件下，快速、高精度确定多个目标的距离、速度、方位等参量是车载雷达信号处理的关键技术之一。本文围绕着自适应接收波束形成、时-空二维谱估计和对目标高度判定等方面进行研究，主要研究工作包括以下几个方面： 1 讨论了在接收阵列天线中，自适应数字波束形成(DBF)的方法，引入了采样梯度矩阵算法。仿真表明，采用自适应算法能够在保证接收方向回波信号幅度保持不变的条件下，抑制干扰信号，且使阵列输出功率最小。 2 讨论了在接收DBF条件下，回波信号的二维谱估计技术。建立了基于调频连续波体制雷达下回波信号的数学模型，并将空间平滑技术推广到时-空二维谱估计，解决了相干信号源的频率-方位估计问题。比较了二维MUSIC算法和基于二维FFT的目标参量测定方法，仿真表明，在相同条件下，基于二维谱估计的方法比基于二维FFT的方法目标分辨率可提高一倍。 3 提出了一种采用波束扫描与多波束目标幅度比较相结合实现目标高度测定的方法。 结果表明，对于100米处目标反射中心在其几何中心处的理想目标，高度测量平均误差小于0.05米。 4 给出了水平方向采用二维谱估计技术测距离、速度和方位，垂直方向采用波束扫描测高的小型车载相控阵雷达系统框图。更多还原

【Abstract】 The technology of measuring of the distance, velocity and azimuth of multi-object accurately and quickly in messy environment is one of the key technologies in signal processing of radar, which is based on vehicle. This dissertation is focused on the study of adaptive digital beam forming(DBF), two-dim spectrum estimation and the determination of the highness of the object. Main work include:1 A method of adaptive DBF in received antenna array. The results of the simulations show this method can keep the amplitude of the desired signal, restrain the interference signal, and keep the output power of array to minimum.2 A mathematical model of the reflected signal based on the frequency modulation continuous wave(FMCW) radar, solving the frequency-azimuth estimation of coherent signals by spatial smoothing technology, comparing the resolution of the object based on two-dim MUSIC method and that based on two-dim FFT. The results of simulation show the resolution based on two-dim spectrum method is 2 times high than that based on two-dim FFT.3 A method of determining the highness of an ideal object by beam scanning in the vertical plane and amplitude comparison.4 A block diagram of phased array radar used which is used to measuring the distance, velocity and azimuth of the object in the horizontal plan and the highness in the vertical plane.更多还原