多波束阵列天线系统信道校准方法

Channel calibration method for multi-beam array antenna system

基于Butler矩阵多波束天线系统实现蜂窝小区覆盖的基本原理和对多波束相关系数与阵列单元间距关系的研究,提出了在天线方向图矢量中引入窗函数和改变阵列单元间距的方法以改进系统的性能.针对无线信道衰落特性的不确定性以及Butler矩阵多波束网络的随机误差,给出了一种多波束阵列天线幅相误差的改进校准方法.该方法采用非正弦信号AC(alternating code)码作为正交编码信号集,发送一组正交编码信号到多波束阵列天线,接收端相干检测并以向量的形式累积,通过正交编码矩阵的逆矩阵解码得到校正因子,利用校正因子对Butler多波束天线的幅相误差进行修正.仿真结果表明该校准算法准确、有效,经幅相误差校准的多波束阵列天线可以实现小区的多波束覆盖.

Based on the principle of Butler matrix to realize coverage of cellular cell and the investigation of the relationship between correlation coefficient and multi-beam array spacing, a method to improve system performance is proposed by introducing window function in the vector of antenna pattern and changing the array element spacing. Aiming at the indetermination of the wireless fading channel characteristics as well as the random error of multi-beam Butler matrix network, an improved calibration method of amplitude and phase errors in multi-beam array antennas is presented. Nonsinusoidal orthogonal signals alternating code （AC） are chosen as an orthogonal encoded signal set and sent to the multi-beam array antenna. In the receiver, coherent detection and vector accumulation are employed to decode the received signal using the inverse of the encoded matrix, a set of correction factors are found and then used to amend errors of amplitude and phase for Butler multi-beam antenna. Simulation results show that the calibration method by nonsinusoidal orthogonal signals set is accurate and effective in the multi-beam array antenna of wireless channels for preassigned cellular coverage.