06084826 is referenced by 208 patents and cites 10 patents.

This invention is directed toward apparatus and methods for obtaining acoustic measurements or "logs" of earth formations penetrated by a borehole. More particularly, the invention is directed toward obtaining the acoustic measurements while the borehole is being drilled. The downhole apparatus comprises a plurality of segmented transmitters and receivers which allows the transmitted acoustic energy to be directionally focused at an angle ranging from essentially 0 degrees to essentially 180 degrees with respect to the axis of the borehole. Downhole computational means and methods are used to process the full acoustic wave forms recorded by a plurality of receivers. A two way communication system is also used in the preferred embodiment of the invention.

Title
Measurement-while-drilling acoustic system employing multiple, segmented transmitters and receivers
Application Number
371879
Publication Number
6084826
Application Date
May 26, 1998
Publication Date
July 4, 2000
Inventor
James V Leggett III
Houston
TX, US
Agent
Madan Mossman & Sriram P C
Assignee
Baker Hughes Incorporated
TX, US
IPC
H04H 9/00
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