Patent Number: 6,426,918

Title: Correlation speed sensor

Abstract: A relative speed of an object is determined by monitoring random reflective surfaces in water. The system includes a first and second transmitter-receiver pair for producing echo signals of a monitored region. The monitoring pair of transducers are preferably positioned along an axis of motion of the object such that sampled data from the first and second transmitter-receiver pair are substantially similar but shifted in time due to a separation of transducers. Echo signal data from the transducers are then used to generate a time difference correlation function that is used to determine a time difference between the first and second signals. Based on the time difference between the time-shifted echo signals, a speed of a vessel is determined.

Inventors: Bartz; James C. (Kailua, HI), Tancrell; Roger H. (Wilmington, MA), Boucher; Stephen G. (Amherst, NH)

Assignee: Airmar Technology Corporation

International Classification: G01P 5/18 (20060101); G01P 5/22 (20060101); G01S 15/60 (20060101); G01S 15/58 (20060101); G01S 15/00 (20060101); G01S 7/523 (20060101); G01S 7/526 (20060101); G01S 015/58 ()

Expiration Date: 07/30/2019