在不同定向时模型化天线对测量时延的影响、提高台站坐标与源坐标等天测与测地参数的解析精度等方面,高精度监测VLBI天线参考点和轴线偏差等参数,具有重要意义。基于对天线旋转模式的特殊限定VLBI天线参数的常规监测方式,占用望远镜工作时间,且监测效率低、所得参数精度差。通过参数化VLBI天线的旋转运动,及建立天线固连合作目标在局域网中坐标的数学模型,有望实现全自动天线参数监测而不影响望远镜的正常观测运行时间。在监测模型构建、解算参数设置和约束条件选取等方面提出了见解,仿真分析验证了其合理性与有效性,并考察了VLBI天线上安装靶标的数目、VLBI天线定向数目、靶标定位精度以及编辑靶标定位数据等因素对天线参数解析精度的影响,所得初步结论供参考。
The monitoring of the reference point and axis offset of VLBI antenna with high precision is of importance to modeling the spatial variation of delay observations as the changing of antenna orientation, the improvement of determination precision of astrometric and geodetic parameters such as station and source coordinates and so on. The nowadays ordinary monitoring method of VLBI antenna is mainly based on some special restrictions to the rotation mode of antenna, which would occupy the effective time of operation of the telescope, the efficiency of the monitoring and the precision of determined parameters are limited. By parameterizing the rotation of VLBI antenna and modeling the coordinates of targets fixed on VLBI antenna in the local control network, it is expected to perform automatic monitoring of antenna parameters without any interruption of normal observation operations of the telescope. Some insights and analysis are presented concerning the establishment of monitoring model, the settings of parameters and the selection of constraints to observation equations, which are verified via simulation analysis to be rational and effective. The effects of the number of targets, the number of antenna orientations, the precision of target positioning observations and the selection of target positioning observations on the determination precision of antenna parameters are also analyzed, and some preliminary conclusions are given for reference for readers.