关于单天线跟踪指向校准和双天线基线校准的探讨  

Search of the Methods for Calibrating the Single-Antenna Tracking/Pointing and Baselines of Pairs of Antennas

作　　者：窦玉江[1,2,3] Dale Gary 颜毅华[1] 王威[1] 刘飞[1] 陈志军[1] 姬国枢[1] 

机构地区：[1]中国科学院国家天文台,北京100012 [2]New Jersey Institute of Technology,newjersey07102 [3]北京师范大学,北京100875

出　　处：《天文研究与技术》2009年第3期202-208,共7页Astronomical Research & Technology

基　　金：国家重点基础研究计划(973计划)项目(G2000078403;2006CB806301);中国科学院天文联合基金(10778605)

摘　　要：阐述了CSRH的跟踪指向校准和天线对基线校准的方法。通过利用观测射电星Cassiopeia A或Cygnus A找出流量最大点以校准天线指向,跟踪观测GPS卫星或射电星,并借鉴Korean Solar Radio Burst Locator(KSRBL)系统的8参数校准法校正由天线安装引入的误差,校准后误差RMS值可小于22"。在完成上述单天线指向跟踪校准后,应用《Interferometry and Synthesis in Radio Astronomy》阐述的算法可校准天线对基线误差。The Chinese Solar Radio Heliograph is an interferometric array consisting of 100 parabolic antennas with a 3km maximum baseline which allows it to obtain images at chosen frequencies ranging from 400MHz to 15GHz. The observing site will be at the town of Ming An Tu in the Inner Mongolia autonomous region. This paper describes the methods of how to calibrate the tracking/pointing and baselines. For the pointing and tracking of a single antenna, the calibrations can be achieved to have the residual rms pointing errors within 22, by （i） observing the radio source Cassiopeia A or Cygnus A to find the maximum - flux direction as the reference to correct the pointing of the antenna, （ii） tracking observations of the GPS satellites and well-documented radio sources, and （iii） using an 8-parameter calibration method that has been effectively applied to the Korean Solar Radio Burst Locator （KSRBL）. After the pointings/trackings of single antennas are calibrated in this way, the baselines of pairs of antennas can be calibrated with a method as illustrated in the ＂ Interferometry and Synthesis in Radio Astronomy＂ by A. R. Thompsom et al. The residual errors of the baselines are less than - 1 mm.

关 键 词：指向精度 跟踪精度 安装误差 基线误差 

分 类 号：P111[天文地球—天文学]