According to the presented sensor array form , the corresponding mathematical mode1 is established , and factors which influence tde accuracy have been analyzed in detail . the influence of tde accuracy to the estimation of tafget distance and bearings estimation is discussed also . meanwhile , the limitation of passive tracking methods and the difference between passive positioning and passive tracldng which based on three - element array are discussed 论文的主要研究工作有以下几个方面: 1 )针对三元直线阵的阵列形式,建立了相应的数学模型,对影响时延估计精度的因素进行了详尽的分析和研究,讨论了时延估计精度对目标距离和方位估计精度的影响,并讨论了三基元被动定位的局限性以及被动定位和被动跟踪的差别。