Method and apparatus for measurement-while-drilling utilizing improved antennas
First Claim
1. An antenna assembly for use in a wellbore for communicating electromagnetic energy, comprising:
- an elongated member with an outer peripheral surface having a contoured portion including a plurality of discrete communication regions of reduced radial dimension and a plurality of land members having a radial dimension substantially equivalent to said outer peripheral surface of said elongated member, with said plurality of discrete communication regions and said plurality of land members being located to define a plurality of alternating groove and land portions;
an antenna pathway defined in said elongated member substantially transverse to said plurality of alternating groove and land portions; and
an antenna member at least partially disposed in said antenna pathway with portions of said antenna member extending out of said elongated member at said plurality of discrete communication regions to facilitate communication of said electromagnetic energy, and extending into said elongated member at said plurality of land members.
3 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus is provided for measurement-while-drilling utilizing improved antennas. An elongated tubular member is provided with an outer peripheral surface having a contoured portion defining a plurality of discrete communication regions of reduced radial dimension. An antenna pathway is defined in the elongated member substantially transverse to the plurality of discrete communication regions. An antenna member is partially disposed in the antenna pathway with portions of the antenna member extending out of the elongated member at the plurality of discrete communication regions to facilitate communication of electromagnetic energy. In a reception mode of operation, the antenna member detects electromagnetic energy in the wellbore and generates a current corresponding thereto. If operated in a transmission mode of operation, the antenna member emits electromagnetic energy in the wellbore in response to an energizing current. Preferably, the plurality of discrete communication regions are circumferentially disposed about the elongated member. Means is provided for preferentially communicating electromagnetic energy with particular portions of the antenna member which are disposed in the plurality of discrete communication regions. In one particular embodiment, a plurality of electrically-operable magnetic circuit elements are provided for communicating with particular ones of the plurality of discrete communication regions of the antenna member, for altering antenna gain in response to at least one control signal.
-
Citations
72 Claims
-
1. An antenna assembly for use in a wellbore for communicating electromagnetic energy, comprising:
-
an elongated member with an outer peripheral surface having a contoured portion including a plurality of discrete communication regions of reduced radial dimension and a plurality of land members having a radial dimension substantially equivalent to said outer peripheral surface of said elongated member, with said plurality of discrete communication regions and said plurality of land members being located to define a plurality of alternating groove and land portions; an antenna pathway defined in said elongated member substantially transverse to said plurality of alternating groove and land portions; and an antenna member at least partially disposed in said antenna pathway with portions of said antenna member extending out of said elongated member at said plurality of discrete communication regions to facilitate communication of said electromagnetic energy, and extending into said elongated member at said plurality of land members. - View Dependent Claims (2, 3, 4, 5)
-
-
6. An antenna assembly for use in a wellbore for communicating electromagnetic energy, comprising:
-
an elongated member; an antenna pathway defined in said elongated member; an antenna member at least partially disposed in said antenna pathway with portions of said antenna member defining a plurality of discrete communication regions to facilitate communication of said electromagnetic energy; and a plurality of electrically-operable magnetic circuit elements, communicating with particular ones of said plurality of discrete communication regions of said antenna member, for altering antenna gain in response to at least one control signal. - View Dependent Claims (7, 8, 9, 10)
-
-
11. An antenna assembly, for use in a drillstring in a measurement-while-drilling system, during drilling operations to interrogate a borehole and surrounding formation, utilizing electromagnetic energy comprising:
-
a tubular member for coupling in a selected position within said drillstring during drilling operations, said tubular member including (a) an inner peripheral surface defining a central bore (b) an outer peripheral surface, and (c) a tubular body defined therebetween; an antenna pathway defined in said tubular body of said tubular member; an antenna member at least partially disposed in said antenna pathway; wherein said tubular member includes a contoured portion which defines a plurality of interleaved groove regions having a reduced radial dimension and land regions formed in said tubular body; and wherein said antenna pathway traverses said plurality of interleaved groove regions and land regions of said contoured portion; and wherein said antenna member extends out of said tubular body of said tubular member at each of said plurality of groove regions to facilitate communication of said electromagnetic energy between said antenna member and said borehole and surrounding formation and passes into said plurality of land regions. - View Dependent Claims (12, 13, 14, 15, 16, 17, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46)
-
-
18. An antenna assembly according to claim 18, wherein each of said at least one antenna coil comprises a single loop antenna coil.
-
47. An improved antenna member for use in a measurement-while-drilling system, during drilling operations in a wellbore, comprising:
-
a tubular member for coupling in a selected location within a drillstring; a plurality of axial grooves (1) cut into said tubular member at particular azimuthal locations and (2) defining a plurality of land regions therebetween; a circular antenna conduit (1) substantially concentric with a central longitudinal axis of said tubular member, (2) extending through each of said plurality of land regions, and (3) communicating with each of said plurality of axial grooves; and an antenna winding extending through said circular antenna conduit for transmitting or receiving electromagnetic radiation at portions of said antenna winding located in said plurality of axial grooves. - View Dependent Claims (48, 49, 50, 51, 52, 53, 54)
-
-
55. A measurement-while-drilling apparatus for use during drilling operations to interrogate a borehole and surrounding formation, comprising;
-
a transmitting member including at least one transmitting antenna for receiving an energizing electrical current and for selectively generating an interrogating electromagnetic signal for propagation through said borehole and surrounding formation; a receiving member, spaced apart from said transmitting member, and including at least one receiving antenna for detecting an interrogating electromagnetic signal and generating an electrical current representative thereof; a signal processing member for identifying at least one characteristic of said interrogating electromagnetic signal which is representative of at least one property of at least one of (1) said borehole, and (2) said surrounding formation; a tubular member of coupling in a selected position within said drillstring and for supporting said transmitting member, said receiving member, and said signal processing member; an antenna assembly, for use in at least one (a) said transmitting member, and (b) said receiving member, including; (1) an antenna pathway, with a plurality of enclosed pathway portions surrounded by said tubular member, and a plurality of open pathway portions with said tubular member only partially surrounding each of said plurality of open pathway portions; (2) an antenna member disposed in said antenna pathway; (3) wherein said electromagnetic energy is preferentially communicated between said antenna member and said borehole and surrounding formation at said plurality of open pathway portions in comparison with said plurality of enclosed pathway portions. - View Dependent Claims (56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67)
-
-
68. A measurement-while-drilling apparatus for use during drilling operations to interrogate a borehole comprising:
-
a transmitting member including at least one transmitting antenna for receiving an energizing electrical current and for selectively generating an interrogating electromagnetic signal for propagation through said borehole and surrounding formation; a receiving member, spaced apart from transmitting member, including at least one receiving antenna for detecting said interrogating electromagnetic signal and generating an electrical current representative thereof; a signal processing member for identifying at least one characteristic of said interrogating electromagnetic signal which is representative of at least one property of at least one of (1) said borehole, and (2) said surrounding formation; a tubular member of coupling in a selected position within said drillstring and for supporting said transmitting member, said receiving member, and said signal processing member; an antenna assembly, for use in at least one of (a) said transmitting member, and (2) said receiving member, including; (1) an antenna pathway at least in part disposed within and surrounded by said tubular member; (2) an antenna member disposed in said antenna pathway; focus means for preferentially communicating electromagnetic energy between at least one portion of said antenna member and said borehole and surrounding formation. - View Dependent Claims (69, 70)
-
-
71. A method of interrogating a borehole surrounding a formation with an electromagnetic interrogating field, comprising the method steps of:
-
providing an elongated member with an antenna pathway defined therein with an antenna member at least partially disposed in said antenna pathway with portions of said antenna member defining a plurality of discrete communication regions; selectively communicating said electromagnetic interrogating field between said antenna member and said borehole surrounding formation at particular ones of said portions of said antenna member defining a plurality of discrete communication regions. - View Dependent Claims (72)
-
Specification