Patent ID: 11947003
Assignee: KING ABDULLAH UNIVERSITY OF SCIENCE AND TECHNOLOGY
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
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 which is separated from the target, a second ultrasound signal R, which corresponds to a propagation of the first ultrasound signal T from the target to the receiver, wherein the second ultrasound signal R includes a second differential Zadoff-Chu sequence y;
applying a maximum likelihood estimator to the first ultrasound signal T and the second ultrasound signal R to calculate an initial time of flight estimate {circumflex over (τ)}corr; and
calculating an initial range estimate {circumflex over (d)}corr of the target by multiplying the initial time of flight estimate {circumflex over (τ)}corr with a speed of sound c,
wherein a differential Zadoff-Chu sequence is different from a Zadoff-Chu sequence, and
wherein 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 sequence.