# US 8,783,346 B2 · System and method for improving operational characteristics > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,346 B2 - Document ID: US8783346B2 - Status: Granted - Kind: B2 - Application number: 13/909,590 - Filed: 2013-06-04 - Published: 2013-10-10 - Granted: 2014-07-22 - Earliest claimed: 2008-05-23 - Assignees: Schlumberger Technology Corporation - Applicants: Schlumberger Technology Corporation - Inventors: Reza Taherian; Henry N. Bachman - Web page: https://patentgrep.com/patent/US8783346B2 ## CPC - E21B 47/017: Protecting measuring instruments - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract In one embodiment, an apparatus includes an antenna having a conductive winding, with the antenna disposed about a channel. A characteristic improvement material is disposed between the antenna and the channel. In some embodiments, the characteristic improvement material includes at least one of a negative stiffness material or a negative Poisson's ratio material. Various systems and methods are also disclosed herein. ## Claims ### Claim 1 An apparatus comprising: a conductive material having a channel formed therethrough; a first layer of composite material disposed about the conductive material and comprising a characteristic improvement material comprising at least one of a negative stiffness material or a negative Poisson's ratio material; an antenna separate from the first layer of composite material and disposed about the first layer of composite material, the antenna comprising at least one conductive winding a second layer of composite material disposed around the antenna, the second layer of composite material being separate from the antenna and the first layer of composite material; and non-conductive layer of material disposed around the second layer of composite material. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the composite material comprises a distribution of a base material and the characteristic improvement material. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the composite material comprises a distribution of a high magnetic permeability material and the characteristic improvement material. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the characteristic improvement material is arranged in one or more layers or strips within a base material to form the composite material. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the apparatus comprises a while-drilling logging tool and the channel comprises a generally cylindrical mud channel. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the apparatus comprises a wireline logging tool and the channel comprises a through-wiring channel. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the at least one conductive winding comprises at least one coil winding. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the at least one coil winding comprises a first x-coil winding and a first y-coil winding. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the at least one coil winding comprises a second x-coil winding and a second y-coil winding, wherein the x-coil windings and the y-coil windings are arranged in an alternating manner. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the x-coil windings are diametrically opposed to each other and the y-coil windings are diametrically opposed to each other. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein the second layer of composite material improves mechanical integrity of the conductive winding. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the antenna is part of a resistivity logging tool, a nuclear magnetic resonance logging tool, or a telemetry tool. ### Claim 13 (depends on 1) The apparatus of claim 1, wherein the second layer of composite material also comprises a characteristic improvement material. ### Claim 14 A method for manufacturing a downhole apparatus comprising: providing a conductive cylindrical structure having an opening formed therethrough defining a channel; disposing a first layer of composite material about the conductive cylindrical structure, wherein the first layer of composite material comprises a characteristic improvement material comprising at least one of a negative stiffness material or a negative Poisson's ratio material; disposing an antenna about the first layer of composite material, wherein the antenna comprises at least one conductive coil winding and is separate from the first layer of composite material; disposing a second layer of composite material about the antenna, wherein the second layer of composite material is separate from the antenna and the first layer of composite material; and disposing a non-conductive layer of material about the second layer of composite material. ### Claim 15 (depends on 14) The method of claim 14, wherein the second layer of composite material also comprises a characteristic improvement material. ### Claim 16 (depends on 14) The method of claim 14, wherein the layer of composite material comprises at least one of a distribution of a base material and the characteristic improvement material or a distribution of a high magnetic permeability material and the characteristic improvement material. ### Claim 17 (depends on 14) The method of claim 14, wherein the composite material is the substrate of a flexible printed circuit board. ### Claim 18 (depends on 14) The method of claim 14, wherein the downhole apparatus comprises a while-drilling logging tool and the channel comprises a generally cylindrical mud channel formed within a conductive cylindrical structure.