CPC G01S 11/14 (2013.01) [G01S 3/808 (2013.01); G01S 15/74 (2013.01); H04J 13/0062 (2013.01)] | 18 Claims |
1. A method for estimating a range of a moving target, the method comprising:
emitting, from a target, a first ultrasound signal T, wherein the first ultrasound signal T is generated based on a first differential Zadoff-Chu sequence x;
receiving, at a receiver, a second ultrasound signal R, which corresponds to the first ultrasound signal T, wherein the second ultrasound signal R includes a second differential Zadoff-Chu sequence y;
correlating the first ultrasound signal T with the second ultrasound signal R to calculate an initial time of flight estimate τcorr; and
calculating an initial range estimate dcorr by multiplying the initial time of flight estimate τcorr with a speed of sound c,
wherein the first and second differential Zadoff-Chu sequences are different from a Zadoff-Chu sequence as the first and second differential Zadoff-Chu sequences are periodic, with a period of: (1) N if N is odd and not divisible by 3, (2) 3N if N is odd and divisible by 3, (3) 4N if N is even and either (2N−1) or (N−1) is divisible by 3, and (4) 12N otherwise, where N is a length of the first and second differential sequences.
|