The measurements can come from the time of arrival (TOA), the time sum of arrival (TSOA), the time difference of arrival (TDOA), and the angle of arrival (AOA).

• 定位之前的量测，有相对于距离的时间(如:抵达时间、抵达时间和、抵达时间差)量测与抵达入射角度的方向量测。