Abstract: An implantable medical device (“IMD”) as described herein includes an adjustable data retransmission scheme, which controls the manner in which data is retransmitted by the IMD. The retransmission feature can be adjusted in a dynamic manner based upon the type, context, or meaning of the telemetry data transmitted by the IMD. The IMD may process contextual meaning information that influences its data retransmission configuration. Such adjustability enables the IMD to satisfy minimum telemetry requirements in a manner that does not waste power, thus extending the IMD battery life.

Abstract: An implantable medical device (“IMD”) as described herein includes adjustable power characteristics such as variable transmitter output power and variable receiver front end gain. These power characteristics can be adjusted in a dynamic manner based upon various operating aspects of the intended or actual IMD telemetry environment. These operating aspects may include the external telemetry device type, the IMD device type, and/or the type, context, or meaning of the telemetry data transmitted by the IMD. The IMD may process information related to these operating aspects to generate power scaling instructions or control signals that are interpreted by the IMD transmitter and/or the IMD receiver. Such adjustability enables the IMD to satisfy minimum telemetry requirements in a manner that does not waste power, thus extending the IMD battery life.

Abstract: Unscheduled wireless communication with a medical device is achieved by operating a receiver of the medical device in a series of modes. Each mode provides an increasingly selective evaluation of received RF energy. The receiver, when operating in a first mode, is capable of detecting the presence of RF energy transmitted from a communicating device. The receiver, when operating in a second mode, consumes more energy than the first mode and analyzes the RF energy to determine whether it contains the appropriate type of modulation. When operating in a third mode, the receiver consumes more energy than the second mode, and operates the full receiver to begin communication with the communicating device. The receiver opens a communication session after the RF energy has passed the evaluation by the series of modes to receive an unscheduled communication.

Abstract: Unscheduled wireless communication with a medical device is achieved by operating a receiver of the medical device in a series of modes. Each mode provides an increasingly selective evaluation of received RF energy. The receiver, when operating in a first mode, is capable of detecting the presence of RF energy transmitted from a communicating device. The receiver, when operating in a second mode, consumes more energy than the first mode and analyzes the RF energy to determine whether it contains the appropriate type of modulation. When operating in a third mode, the receiver consumes more energy than the second mode, and operates the full receiver to begin communication with the communicating device. The receiver opens a communication session after the RF energy has passed the evaluation by the series of modes to receive an unscheduled communication.

Abstract: Unscheduled wireless communication with a medical device is achieved by operating a receiver of the medical device in a series of modes. Each mode provides an increasingly selective evaluation of received RF energy. The receiver, when operating in a first mode, is capable of detecting the presence of RF energy transmitted from a communicating device. The receiver, when operating in a second mode, consumes more energy than the first mode and analyzes the RF energy to determine whether it contains the appropriate type of modulation. When operating in a third mode, the receiver consumes more energy than the second mode, and operates the full receiver to begin communication with the communicating device. The receiver opens a communication session after the RF energy has passed the evaluation by the series of modes to receive an unscheduled communication.

Abstract: A low power multiple channel receiver mixing architecture for detecting wake-up signals over multiple communication channels in sniff processing performed in an implantable medical device (IMD). The architecture includes a direct conversion real receiver configured to scan a selected center channel and a Weaver receiver configured in parallel to the direct conversion real receiver to simultaneously scan side channels, together simultaneously detecting whether a wake-up signal is being received over the center and side channels with minimal power consumption. The architecture further utilizes a falsing protection algorithm that reduces power consumption during sniff operations by inhibiting the sniffing of channels likely to provide a false indication of a wake-up signal based the presence of unwanted signals on those channels.

Abstract: Embodiments of the invention include channel selection and mapping for medical device communication. The communication system can implement a two-stage listen before talk protocol to choose a channel for communication. The first stage samples the interference of each channel for a relatively short time and chooses the best signal. The second stage samples the channel selected by the first stage and samples it for a relatively longer time to confirm the channel selected by the first stage is the best channel for communication.

Abstract: An implantable medical device (IMD) includes a telemetry module to communicate with an external device according to a given protocol. To establish a communication session, the IMD will extend active periods of reception on a given channel when some confirmed data is received from the external device. In addition, once a session has been opened, the programmer transmits a short data set (or preamble) for each cycle which the IMD is set to receive. This data set indicates whether additional data will or will not be sent. If no additional data is to be sent during that cycle, then the IMD powers down the receiver for that cycle.

Abstract: An implantable medical device (IMD) includes a telemetry module to communicate with an external device according to a given protocol. To establish a communication session, the IMD will extend active periods of reception on a given channel when some confirmed data is received from the external device. In addition, once a session has been opened, the programmer transmits a short data set (or preamble) for each cycle which the IMD is set to receive. This data set indicates whether additional data will or will not be sent. If no additional data is to be sent during that cycle, then the IMD powers down the receiver for that cycle.

Abstract: An implantable medical device (“IMD”) as described herein includes adjustable power characteristics such as variable transmitter output power and variable receiver front end gain. These power characteristics are adjusted based upon the intended or actual implant depth of the IMD. The IMD may process an IMD implant depth value (provided by an external IMD programming device) to generate power scaling instructions or control signals that are interpreted by the IMD transmitter and/or the IMD receiver. Such adjustability enables the IMD to satisfy minimum telemetry requirements in a manner that does not waste power, thus extending the IMD battery life.

Abstract: A low power multiple channel receiver mixing architecture for detecting wake-up signals over multiple communication channles in sniff processing performed in an implantable medical device (IMD). The architecture includes a direct conversion real receiver configured to scan a selected center channel and a Weaver receiver configured in parallel to the direct conversion real receiver to simultaneously scan side channels, together simultaneously detecting whether a wake-up signal is being received over the center and side channels with minimal power consumption. The architecture further utilizes a falsing protection algorithm that reduces power consumption during sniff operations by inhibiting the sniffing of channels likely to provide a false indication of a wake-up signal based the presence of unwanted signals on those channels.

Abstract: An implantable medical device (IMD) includes a telemetry module to communicate with an external device according to a given protocol. To establish a communication session, the IMD will extend active periods of reception on a given channel when some confirmed data is received from the external device. In addition, once a session has been opened, the programmer transmits a short data set (or preamble) for each cycle which the IMD is set to receive. This data set indicates whether additional data will or will not be sent. If no additional data is to be sent during that cycle, then the IMD powers down the receiver for that cycle.

Abstract: Embodiments of the invention include channel selection and mapping for medical device communication. The communication system can implement a two-stage listen before talk protocol to choose a channel for communication. The first stage samples the interference of each channel for a relatively short time and chooses the best signal. The second stage samples the channel selected by the first stage and samples it for a relatively longer time to confirm the channel selected by the first stage is the best channel for communication.

Abstract: An implantable medical device (“IMD”) as described herein includes an adjustable data retransmission scheme, which controls the manner in which data is retransmitted by the IMD. The retransmission feature can be adjusted in a dynamic manner based upon the type, context, or meaning of the telemetry data transmitted by the IMD. The IMD may process contextual meaning information that influences its data retransmission configuration. Such adjustability enables the IMD to satisfy minimum telemetry requirements in a manner that does not waste power, thus extending the IMD battery life.

Abstract: An implantable medical device (“IMD”) as described herein includes adjustable power characteristics such as variable transmitter output power and variable receiver front end gain. These power characteristics can be adjusted in a dynamic manner based upon various operating aspects of the intended or actual IMD telemetry environment. These operating aspects may include the external telemetry device type, the IMD device type, and/or the type, context, or meaning of the telemetry data transmitted by the IMD. The IMD may process information related to these operating aspects to generate power scaling instructions or control signals that are interpreted by the IMD transmitter and/or the IMD receiver. Such adjustability enables the IMD to satisfy minimum telemetry requirements in a manner that does not waste power, thus extending the IMD battery life.

Abstract: Uplink and downlink telemetry between an implantable medical device (IMD) telemetry transceiver and an external medical device (EMD) telemetry transceiver used by a patient or health care provider is facilitated by the communications system of the present invention. The IMD provides a therapy and/or measures physiologic conditions of the patient for use in formulating a therapy and/or for storage in IMD memory for later uplink telemetry transmission. The patient causes the EMD to emit encoded dual tone multiple frequency (DTMF) tones that are detected by an audio receiver of the IMD to enable uplink and downlink telemetry transmissions in a telemetry or communication session. Then, the patient formulates a message via a message entry mechanism of the EMD that communicates an instruction or query to the IMD. The downlink message is optionally displayed by an EMD display as it is composed by the user and is then downlink telemetered to the IMD.

Abstract: In an implantable medical device, a frequency synthesizer employed in the RF transceiver of the IMD operating system functions in a PLL LOCK mode wherein the VCO frequency is governed by the PLL and an energy saving HOLD mode wherein the PLL is not operational and the VCO generated carrier frequency can drift over time. The PLL circuit is powered up and coupled with a control voltage input and the output of the VCO to develop a frequency control voltage stored by a capacitive loop filter during initial LOCK portions of both uplink and downlink telemetry transmission time periods. A frequency modulation (FM) input of the VCO receives data bit modulation voltages that modulates the carrier frequency during uplink transmission of patient data.

Abstract: Uplink and downlink telemetry between an implantable medical device (IMD) telemetry transceiver and an external medical device (EMD) telemetry transceiver used by a patient or health care provider is facilitated by the communications system of the present invention. The IMD provides a therapy and/or measures physiologic conditions of the patient for use in formulating a therapy and/or for storage in IMD memory for later uplink telemetry transmission. The patient causes the EMD to emit encoded dual tone multiple frequency (DTMF) tones that are detected by an audio receiver of the IMD to enable uplink and downlink telemetry transmissions in a telemetry or communication session. Then, the patient formulates a message via a message entry mechanism of the EMD that communicates an instruction or query to the IMD. The downlink message is optionally displayed by an EMD display as it is composed by the user and is then downlink telemetered to the IMD.

Abstract: An implantable medical device and a method of operation thereof. The implantable device includes apparatus for delivering a therapy to a patient or monitoring a physiologic parameter of a patient and control circuitry for modifying operation of the device. The device further includes an audio receiver responsive to sequences of DTMF tones and coupled to the control circuitry, which modifies the operation of the device responsive to received DTMF tone sequences. The device preferably includes a telemetry system and the control circuitry may modify operation of the telemetry system responsive to received DTMF tone sequences. In addition or alternatively, the control circuitry may modify operation of the apparatus for delivering a therapy to a patient or monitoring a physiologic parameter responsive to received DTMF tone sequences. The device may further include an audio tone generator for generating a tone or series of tones indicative of operation or status of the device.

Abstract: The present invention reduces the distortion components produced from high power level mixing through a set of adaptive cancelling circuits which utilize a low power level mixing of the same signals to provide a signal which is adaptively cancelled with a signal representative of the high power level signal including distortion to provide an output signal which comprises substantially only the distortion components found in the high power level signal. These distortion components are then adaptively cancelled or combined with the high power level signal including distortion to provide an output signal which comprises the primary signal and insignificant levels of noise and distortion.