Improvement in the method of data processing

When the errors in the initial orbit are comparatively great, the usual truncated least square L estimation can not effectively delete the outliers in the set of optical observations. This method has been modified in both the threshold and the approximation model: the threshold is now determined by the statistics on the rms, and the linear model of fitting the residuals is replaced with a quadratic model. With these modifications, the results show that when the initial orbit has an error of 10[su−4] (the error in the semi-major axis is about 5%), the proportion of outliers is reduced to below 10% for all the simulated satellite passes.