The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 10, 1996
Filed:
Dec. 06, 1993
Richard J Meehan, Cambridge, GB;
Schlumberger Technology Corporation, Sugar Land, TX (US);
Abstract
A method for improving the signal to noise ratio from a pair of detectors such as geophones which each detect a noisy signal comprising a signal of interest (S) and a noise signal (N), wherein the signal of interest (S) has a different moveout across the pair of detectors from that of the noise signal (N), and the noise signal (N) from a given source is detected at the first detector at a time .DELTA.t before the corresponding noise signal is detected at the second detector, the method comprising delaying the noisy signal (S+N) detected at the first detector by an amount .tau. being greater than the moveout of the signal of interest but not more than .DELTA.t and subtracting the delayed signal from that detected at the second detector by means of an adaptive filter so as to minimize the power in the resultant signal. The signal detected at the first detection and optionally the resultant signal can also be delayed by an amount .tau..sub.2 and the signal detected at the second detector is subtracted from the delayed first detector (and resultant signals) by means of an adaptive filter so as to minimize the power in the final signal, the delay .tau..sub.2 being greater than the moveout of the signal of interest plus the length of the filter but not more than .DELTA.t plus the length of the filter.