Abstract: In general, the invention is directed to a coaxial cable antenna for use in an external device, such as a programmer or monitor, to enhance communication between the external device and an implanted medical device (IMD). The coaxial cable antenna provides the external device with polarization diversity. For example, the coaxial cable antenna includes a first portion and a second portion that are substantially perpendicular to one another. Each of the portions of the coaxial cable antenna has a different polarization orientation, thus providing the programmer with polarization diversity. Further, the external device may include more than one coaxial cable antenna to provide the external device with spatial diversity as well as polarization diversity provided by the coaxial cable antenna design. The coaxial cable antenna configurations reduce problems associated with polarization mismatches, antenna nulls, and multi-path propagation interference.

Abstract: A coaxial cable antenna is provided for use in an external device, such as a programmer or monitor, to enhance communication between the external device and an implanted medical device (IMD). The coaxial cable antenna provides the external device with polarization diversity. For example, the coaxial cable antenna includes a first portion and a second portion that are substantially perpendicular to one another. Each of the portions of the coaxial cable antenna has a different polarization orientation, thus providing the programmer with polarization diversity. Further, the external device may include more than one coaxial cable antenna to provide the external device with spatial diversity as well as polarization diversity provided by the coaxial cable antenna design. The coaxial cable antenna configurations reduce problems associated with polarization mismatches, antenna nulls, and multi-path propagation interference.

Abstract: Improved telemetry antennas and methods of fabrication for an implantable medical device (IMD) for use in uplink telemetry (UT) and downlink telemetry (DT) transmissions between the IMD and an external medical device (EMD) are disclosed. A first telemetry antenna element is supported to extend in a first direction along a minor side of the IMD housing by a first header segment, and a second antenna element is supported to extend in a second direction along a second minor side of the IMD housing by a second header segment. The first and second antenna elements are supported to extend apart at substantially 90° to one another, i.e., substantially orthogonally, in substantially a common plane to optimize UT transmission and DT reception of UHF telemetry signals by at least one of the first and second antenna elements depending upon the mutual spatial orientation with the antenna elements of an EMD antenna.

Abstract: A method and an apparatus for reducing coupled electrical energy resulting from an electromagnetic field. Embodiments of the present invention provide for an elongate body having a proximal end portion, a middle portion, and a distal end portion and at least one coil wound about at least one of the proximal end portion, the middle portion, and the distal end portion, the coil to provide for filtering of radio frequency (RF) signal-coupled electrical energy.

Abstract: A coaxial cable antenna for use in an external device, such as a programmer or monitor, to enhance communication between the external device and an implanted medical device (IMD). The coaxial cable antenna provides the external device with polarization diversity. For example, the coaxial cable antenna includes a first portion and a second portion that are substantially perpendicular to one another. Each of the portions of the coaxial cable antenna has a different polarization orientation, thus providing the programmer with polarization diversity. Further, the external device may include more than one coaxial cable antenna to provide the external device with spatial diversity as well as polarization diversity provided by the coaxial cable antenna design. The coaxial cable antenna configurations reduce problems associated with polarization mismatches, antenna nulls, and multi-path propagation interference.

Abstract: Improved telemetry antennas and methods of fabrication for an implantable medical device (IMD) for use in uplink telemetry (UT) and downlink telemetry (DT) transmissions between the IMD and an external medical device (EMD) are disclosed. A first telemetry antenna element is supported to extend in a first direction along a minor side of the IMD housing by a first header segment, and a second antenna element is supported to extend in a second direction along a second minor side of the IMD housing by a second header segment. The first and second antenna elements are supported to extend apart at substantially 90° to one another, i.e., substantially orthogonally, in substantially a common plane to optimize UT transmission and DT reception of UHF telemetry signals by at least one of the first and second antenna elements depending upon the mutual spatial orientation with the antenna elements of an EMD antenna.

Abstract: In general, the invention is directed to a coaxial cable antenna for use in an external device, such as a programmer or monitor, to enhance communication between the external device and an implanted medical device (IMD). The coaxial cable antenna provides the external device with polarization diversity. For example, the coaxial cable antenna includes a first portion and a second portion that are substantially perpendicular to one another. Each of the portions of the coaxial cable antenna has a different polarization orientation, thus providing the programmer with polarization diversity. Further, the external device may include more than one coaxial cable antenna to provide the external device with spatial diversity as well as polarization diversity provided by the coaxial cable antenna design. The coaxial cable antenna configurations reduce problems associated with polarization mismatches, antenna nulls, and multi-path propagation interference.

Abstract: A method and an apparatus for reducing coupled electrical energy resulting from an electromagnetic field. Embodiments of the present invention provide for an elongate body having a proximal end portion, a middle portion, and a distal end portion and at least one coil wound about at least one of the proximal end portion, the middle portion, and the distal end portion, the coil to provide for filtering of radio frequency (RF) signal-coupled electrical energy.

Abstract: A method and an apparatus for trapping induced current resulting from an electromagnetic field. Embodiments of the present invention provide for an elongate body having a proximal and a distal end portion and a coil wound about the distal end, the coil to provide an electromagnetic trap for filtering radio frequency (RF) signal-induced currents.

Abstract: An implantable medical device for delivering a medical therapy or for monitoring physiologic parameters. The device is provided with a hermetic housing containing a transceiver coupled to an antenna located outside the housing by means of a feedthrough, mounted to the housing and coupled to the transceiver. The antenna takes the form of a length of conductor, coupled to the feedthrough. In some embodiments the antenna is an insulated stranded conductor coupled to the feedthrough by means of a metallic loading tab. In other embodiments the antenna includes a length of conductor encased in a dielectric, extending from the feedthrough, and a coaxial shield coupled to the housing and extending along only a portion of the length of conductor.

Abstract: A device for use in communication with an implantable medical device. The device is provided with a spatial diversity antenna array mounted to a housing and an RF transceiver operating at defined frequency, coupled to the antenna alray. The antenna array comprises two antennas spaced a fraction of the wavelength of the defined frequency from one another, each antenna including two antenna elements mounted to the housing and located oithogonal to one another. Selection of which of the antennas is employed is accomplished by an device controller, responsive to the quality of the signals received by the antennas.

Abstract: An antenna (20) has a set of elongated electrically conductive radiating elements (24) disposed about a central mast (26) in the form of a maypole. The radiating elements are electrically connected to each other at a top end of the mast by a top ring (28) and near a bottom end of the mast by a bottom ring (30), both of the rings being electrically insulated from the mast. A positioning unit (32) is located on the mast between the two rings for bowing the radiating elements away from the mast. Sections of the respective radiating elements located between the positioning unit and the bottom ring are severed and connected together by impedance elements (82). Each of the impedance elements includes a resistor (84) which serves as a load for providing a current distribution in a radiating element similar to that of a traveling wave, the impedance elements also having an inductor (86) and a capacitor (88) connected in parallel with the resistor.

Abstract: Dual mode log periodic dipole antenna apparatus which provides for sum and difference radiation patterns depending on the method of excitation. The antenna incorporates a support structure which secures a plurality of radiators having three elements with successively incresing length. The center and right dipole elements of each radiator and the center and left elements of each radiator are alternately coupled together by separate transmission lines in a crisscross fashion. Input ports coupled to the smallest radiator and driven with a conventional hybrid coupler with either in-phase or out-of-phase energy at either .lambda./2 or .lambda.. Sum and difference radiation patterns are achieved by appropriate selection of the excitation phase. Thus, this antenna may be employed in monopulse or direction finding applications. An alternative embodiment is disclosed which employs center radiator elements offset from the right and left elements of their respective radiators.