一种顾及现势指向的上行天线阵相位中心精确标校方法

针对上行天线阵相位中心标校技术粗糙、精度不高等问题,引入精密工程测量技术测定天线实际状态,提出了一种顾及现势指向的相位中心精确标校方法。首先,利用工业摄影测量系统获取天线各姿态的型面数据,并通过最小二乘法拟合求解出现势性强的机械轴;然后,用矩阵法解算各姿态下机械轴的交点作为旋转中心;最后,基于反角度加权插值法推估得到天线在任意姿态下的机械轴,进而从投影中心沿机械轴延伸既定长度获得可靠的相位中心。以3台φ3 m上行阵天线为试验对象,通过工程控制网统一摄影测量坐标系,并按照本文方法标校天线相位中心。电信号合成效果表明,本文方法能有效克服天线自重变形、机械安装等因素的影响,实现了相位中心的精确标校,增强了上行天线阵合成信号的幅度。

A precise calibration method for phase center of uplink antenna array considering its actual pointing

With regard to the inferior techniques and poor accuracy of phase center calibration of antenna array, by the power of precise engineering surveying technique, a new calibration method is proposed considering the actual antenna pointing. First of all, an industrial photogrammetric system is utilized to get the coordinates of points on antenna panels in different postures, and the actual pointing of mechanical axis is obtained by least square fitting. On this basis, the coordinates of antenna rotation center are obtained by seeking the intersection of mechanical axes with the matrix method. Finally, the mechanical axis in arbitrary postures is estimated based on inverse-angle weighting interpolation method, and the reliable phase center is obtained by moving a fixed length from the projective center alone the mechanical axis. An uplink antenna array consists of three φ3 m antennas is taken as experimental object, all photogrammetric coordinate systems are unified by the engineering control network, each antenna phase center is precisely calibrated with this proposed method. The effect of electrical signal synthesis shows that this method can effectively compensate the influence of gravity deformation and machining, and enhance the synthetic signal amplitude of uplink antenna array.