Abstract: An implantable medical device may have an antenna for communication with external devices or other internal devices. Changes in the patient's body position, weight, composition or other factors may change the antenna efficiency and hinder communication. The disclosed circuit may automatically adjust a matching network for an implanted transceiver to dynamically maximize transmission and reception by controlling the selected value of a plurality of capacitors, inductors and resistors.

Abstract: A far-field radio frequency (RF) telemetry system for communicating with an implantable medical device includes a diversity antenna system. Multi-frame messages each including multiple outgoing data frames are transmitted to the implantable medical device. In response, the implantable medical device transmits response data frames each following one or more of the outgoing data frames, according to a predetermined communication protocol. An antenna control circuit selects an antenna of the diversity antenna system for transmitting the outgoing data frames and/or receiving the response data frames based the quality of signal reception associated with the response data frames.

Abstract: An apparatus and method for enabling an implanted fractal antenna for radio frequency communications between an implantable medical device and an external device. The fractal antenna may be disposed within or outside of a header assembly of the device housing. Various examples include a three dimensional patterned cylinder usable as a tissue anchor or stent. In another embodiment the antenna may be cast, molded, stamped, punched, milled, laser cut, etched or other methods to form a fractal pattern in conductive media. In another embodiment the antenna may be formed of a printed circuit board (PCB) either with or without an included ground reference plane. In another embodiment the antenna may be formed in a fractal pattern and then wrapped around a part of the implantable device.

Abstract: In general, the invention is directed to a tunable inductor that makes use of eddy current effect to tune the inductance of an inductor. The tunable inductor may include a spiral or helical inductor in proximity to one or more sets of eddy current coils. Each eddy current coil may be coupled to a corresponding switch that controls whether the eddy current coil is grounded or floating. In operation, a first time-varying current through the inductor induces a first magnetic field that, in turn, induces a time-varying voltage in an eddy current coil. If the eddy current coil is not grounded, an eddy current flows through the eddy current coil. The eddy current, which flows in the opposite direction of the first time-varying current, induces a second magnetic field. The second magnetic field, which opposes the first magnetic field, reduces the inductance of the tunable inductor.

Abstract: A system for communicating with an implantable medical device via RF telemetry is disclosed which mitigates the effects of nulls caused by, e.g., multi-path distortion. In one embodiment, signals transmitted by the implantable device to an external device are simultaneously received with a pair of separate spaced apart first and second antennas. The antennas may provide spatial and/or polar diversity. The presence of nulls in the implantable device's transmission pattern can be determined by detecting an error rate in the signals received from the implantable device with each antenna.

Abstract: A far-field radio frequency telemetry (RF) system for communicating with an implantable medical device includes a diversity antenna system. An antenna control circuit selects one or more antennas of the diversity antenna system for reducing potential data transmission errors associated with nulls encountered by the telemetry system due to environmental reflections of RF electromagnetic waves. In one embodiment, a different active antenna is selected when a transmission failure deemed to be associated with a null is detected. In another embodiment, a new antenna is selected on a regular basis to reduce the probability of encountering a null. In another embodiment, the telemetry system includes multiple processing paths each associated with one antenna of the diversity antenna system, and a different processing path is selected when the transmission failure deemed to be associated with a null is detected.

Abstract: A far-field radio frequency (RF) telemetry system for communicating with an implantable medical device includes a diversity antenna system. Multi-frame messages each including multiple outgoing data frames are transmitted to the implantable medical device. In response, the implantable medical device transmits response data frames each following one or more of the outgoing data frames, according to a predetermined communication protocol. An antenna control circuit selects an antenna of the diversity antenna system for transmitting the outgoing data frames and/or receiving the response data frames based the quality of signal reception associated with the response data frames.

Abstract: An implantable, self-contained, user-attachable or detachable telemetry module plugs into an implantable medical device to provide or supplement one or more telemetry functions needed by a patient having certain health conditions. A user-attachable or detachable telemetry module allows a user, such as a physician or other care provider, to select a telemetry module and attach it to a medical device. Various types of telemetry are implemented as various user-attachable or detachable telemetry modules, each providing one or more telemetry functions suitable for a particular patient whose condition imposes a particular demand on telemetry. A care provider selects a user-attachable or detachable telemetry module most suited for the particular patient, which improves healthcare cost efficiency. One example of user-attachable or detachable telemetry module includes a radio-frequency (RF) transmitter-receiver circuit module and a lead carrying an antenna.

Abstract: An implantable medical device system includes an implanted device communicating with an external device via telemetry. The implanted device and the external device each have a telemetry module connected to an antenna system to support a radio-frequency (RF) telemetry link. The antenna system of the external device has a manually or automatically controllable directionality. The controllable directionality is achieved, for example, by using two or more directional antennas, one non-directional antenna and one or more directional antennas, or an electronically steerable phased-array directional antenna.

Abstract: An implantable medical device system includes an implanted device communicating with an external device via telemetry. The implanted device and the external device each have a telemetry module connected to an antenna system to support a radio-frequency (RF) telemetry link. The antenna system of the external device has a manually or automatically controllable directionality. The controllable directionality is achieved, for example, by using two or more directional antennas, one non-directional antenna and one or more directional antennas, or an electronically steerable phased-array directional antenna.

Abstract: Systems, methods and devices facilitating wireless communication with a medical device employ an antenna that provides for increased efficiency, broader bandwidth, and/or improved impedance matching characteristics. In some cases, this antenna is an inverted-f antenna, and in one particular case, the antenna is a non-planar inverted-f antenna. In some cases, the antenna is disposed within a dielectric housing extending along a portion of the side of the medical device.

Abstract: This document discloses, among other things, a telemetry system for requesting and receiving redundant data. A synchronization frame transmitted by an external device includes an echo code. The implantable device responds to the synchronization frame by sending real time data and echo data selected as a function of the echo code.

Abstract: A telemetry system provides a selectable encoding protocol, including, for example, a plurality of redundancy levels, where the encoding protocol is selected based on a measure of transmission efficiency. For example, later messages are transmitted using an increased redundancy if a prior message exhibits a low signal to noise ratio. A communication session is initiated using a first level of redundancy and the level is adjusted based on a channel characteristic or a measured parameter.

Abstract: An apparatus and method for enabling far-field radio frequency communications with an implantable medical device in which an antenna structure is disposed within a header assembly of the device. The antenna structure, in various embodiments, includes a monopole antenna, a dipole antenna, an inverted F antenna, a patch antenna and a slot antenna.

Abstract: An apparatus and method for enabling far-field radio-frequency communications with an implantable medical device in which an antenna is embedded within a dielectric around the periphery of the device. Such a circumferential antenna saves space while still permitting far-field telemetry over a desired range of frequencies.

Abstract: An implantable medical device system includes an implanted device communicating with an external device via telemetry. The implanted device and the external device each have a telemetry module connected to an antenna system to support a radio-frequency (RF) telemetry link. The antenna system of the external device has a manually or automatically controllable directionality. The controllable directionality is achieved, for example, by using two or more directional antennas, one non-directional antenna and one or more directional antennas, or an electronically steerable phased-array directional antenna.

Abstract: An apparatus and method for enabling far-field radio-frequency communications with an implantable medical device in which an antenna is embedded within a dielectric around the periphery of the device. Such a circumferential antenna saves space while still permitting far-field telemetry over a desired range of frequencies.

Abstract: An apparatus and method for enabling far-field radio-frequency communications with an implantable medical device in which an antenna is embedded within a dielectric around the periphery of the device. Such a circumferential antenna saves space while still permitting far-field telemetry over a desired range of frequencies.

Abstract: An implantable, self-contained, user-attachable or detachable telemetry module plugs into an implantable medical device to provide or supplement one or more telemetry functions needed by a patient having certain health conditions. A user-attachable or detachable telemetry module allows a user, such as a physician or other care provider, to select a telemetry module and attach it to a medical device. Various types of telemetry are implemented as various user-attachable or detachable telemetry modules, each providing one or more telemetry functions suitable for a particular patient whose condition imposes a particular demand on telemetry. A care provider selects a user-attachable or detachable telemetry module most suited for the particular patient, which improves healthcare cost efficiency. One example of user-attachable or detachable telemetry module includes a radio-frequency (RF) transmitter-receiver circuit module and a lead carrying an antenna.

Abstract: An apparatus and method for enabling far-field radio-frequency communications with an implantable medical device in which an antenna is embedded within a dielectric around the periphery of the device. Such a circumferential antenna saves space while still permitting far-field telemetry over a desired range of frequencies.