none line meaning in English

失配线

In 3g communication system , the most promising location method was the locating arithmetic based on the time of arrival and the time difference of arrival ( toa / tdoa ) of signal , or the angle of arrival of signal ( aoa ) . however , either the arithmetic based on toa or that based on aoa was badly affected by the none line of sight ( nlos ) phenomenon
在第三代移动通信系统中,最有前景的定位方式是基于信号到来时间/时间差( toa / tdoa )或信号到来角( aoa )的定位算法。但不管是基于信号到来时间的算法还是基于信号到来角度的算法,定位信号的非视距传播效应( nlos )都会对其造成严重的影响,在影响移动定位精度的诸多因素中nlos效应被公认为是最主要的因素。