A positioning and ranging system includes a transmitter transmits a plurality of impulses; and a receiver receives the impulses; the receiver includes an initial detection unit records a sensing time of a first impulse among a plurality of impulses transmitted by the transmitter; a sensing margin detection unit for detecting a sensing margin being a difference between a field intensity of the first impulse and a reception limit field intensity of the receiver; a correction unit identifies a sensing error differential time based on a given relationship between the sensing margin and the sensing error differential time, and corrects the sensing time detected by the initial detection unit using the identified sensing error differential time; the system measures a distance between the transmitter and the receiver and a position of the transmitter based on a time the transmitter transmits the first impulse and a time the receiver receives the impulse.