Global Patent Index - EP 0159314 A4

EP 0159314 A4 19860723 - NOISE SUBTRACTION FILTER.

Title (en)

NOISE SUBTRACTION FILTER.

Title (de)

GERÄUSCHSUBTRAHIERENDER FILTER.

Title (fr)

FILTRE D'AMORTISSEMENT DU BRUIT.

Publication

EP 0159314 A4 19860723 (EN)

Application

EP 83903340 A 19830926

Priority

US 8301494 W 19830926

Abstract (en)

[origin: WO8501586A1] A filter (36) for use in filtering noise from cyclical signals have a data component and a noise component in which a predetermined number of the cyclical signals are averaged to produce an average signature signal (76). The average signature signal (76) is updated each cycle (74) to produce a current updated average signature signal, and the current cyclical signals and the current updated average signals are substracted (68) from one another to remove the noise component and produce a residual signal (72) which contains the data component. The time frames of the current cyclical signals and the current updated average signals are adjusted (78) to be equal so as to enable point by point subtraction. As an additional feature, the updating of the average signature combines a portion of the last average pump signature with a portion of the last residual signal (74).

IPC 1-7

G01V 1/40; G06F 7/00

IPC 8 full level

E21B 47/18 (2012.01); G01V 1/36 (2006.01); G01V 1/40 (2006.01); G06F 7/00 (2006.01); H03H 21/00 (2006.01)

CPC (source: EP)

E21B 47/18 (2013.01); G01V 1/36 (2013.01); H03H 21/00 (2013.01); G01V 2210/324 (2013.01)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

WO 8501586 A1 19850411; AU 2124683 A 19850423; AU 555850 B2 19861009; EP 0159314 A1 19851030; EP 0159314 A4 19860723; NO 852096 L 19850524

DOCDB simple family (application)

US 8301494 W 19830926; AU 2124683 A 19830926; EP 83903340 A 19830926; NO 852096 A 19850524