this article sets forth the orientation theory of digital television and radio signals'space position, speed, clock error and etc . and then analyses the error, troposphere delay, multipath and shelter domine effect, relying on the creation of hypodistance arithmatic model and the deduction of calculation formulae 摘要文章通过建立伪距数学模型,推导整理出计算公式,从而对数字电视广播信号的空间位置、速度和时钟偏差等参数的定位原理进行了阐述,最后对误差、对流层延迟、多径和遮挡效应等进行了分析。