Abstract: Constituents of a network of medical devices communicate according to a synchronous communication protocol. A constituent of the network is established as a conductor. Time slots are assigned to each constituent of the network other than the conductor. Information is communicated between the constituents of the network in the assigned time slots.

Abstract: Medical data is communicated from a transmitter of an external unit to a receiver of an implantable medical device. The transmitter generates a preamble signal having encoded configuration data that informs the receiver of configuration settings to be used in receiving the medical data. The receiver detects the preamble and validates a modulation pattern of the preamble. Configuration data is decoded from the preamble signal and the receiver configuration is adjusted to receive the medical data.

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: Data is communicated from a transmitter of an external unit to a receiver of an implantable medical device. The receiver of the implantable medical device operates in a wide band receiver mode to detect the transmission from the external unit and operates in a narrow band receiver mode to receive the data.

Abstract: An implantable medical device (“IMD”) configured in accordance with an example embodiment of the invention generally includes a housing, a connector header block coupled to the housing, a dielectric sheath located around at least a portion of the housing and/or around at least a portion of the header block, and a telemetry antenna located within the dielectric sheath. The antenna is configured to support far field telemetry with an external device such as a programmer. In one example embodiment, the antenna is configured as a balanced antenna having two separate antenna elements driven 180 degrees out of phase. Each of the antenna elements has a feed point on a perimeter edge of the IMD housing and a floating endpoint. A number of alternate embodiments are also provided.

Abstract: In some embodiments, a medical device system may include one or more of the following features: (a) an external medical device (EMD), (b) an implantable medical device (IMD) disposed within a hermetically sealed housing adapted for implantation in the body of a patient to provide a therapy delivery and/or monitoring function, (c) two or more transmitters disposed within the EMD, the two or more transmitters uplinking telemetry transmissions generated by the EMD, (d) two or more receivers disposed within the IMD, the two or more receivers downlinking the telemetry transmissions, and (e) the IMD processing the telemetry transmission received by a selected one of the two or more receivers, the selection being based on which receiver is receiving the best quality signal transmission reception.

Abstract: A body implantable medical apparatus includes circuitry for generating and transmitting a modulated analog data signal. A receiver receives and digitally demodulates the modulated analog signal. An analog-to-digital converting circuit produces an amplitude limited modulated digital signal corresponding to the modulated analog signal. The converting circuit includes an amplifier coupled to a receive antenna and a comparator having an input coupled to the amplifier and an output coupled to a digital demodulator. The digital demodulator demodulates the modulated digital signal to produce a digital information signal, such as a signal containing physiologic sensor data. The digital demodulator includes a digital delay line comprising a plurality of shift registers or, alternatively, a plurality of multiple-stage delay blocks each coupled to a tap selection device.

Abstract: A receiving and filtering circuit includes an antenna, a demodulator circuit coupled to the antenna, and a digital median filter that removes high frequency content of a demodulated digital information signal to produce a filtered digital information signal corresponding to an analog data signal transmitted by a body implantable medical apparatus. The digital filter may include a multiple stage delay line coupled to a multiple tap selection device, a plurality of delay blocks coupled to a register, or a multiple stage delay line coupled to a voting unit. The voting unit produces a first binary output in response to a majority of delay line stages storing a first value, and produces a second binary output in response to a majority of delay line stages storing a second value. The digital filter may also comprise a digital signal processor. The digital filter may include a first filter block and a second filter block. The second filter block may be selectively activated or bypassed.

Abstract: A radio frequency transponder is provided that combines high signal sensitivity in the receive mode and variable frequency capability in the transmit mode in a low component and power efficient design. A single tuned amplifier acts as the externally quenched oscillator of a superregenerative receiver when the transponder is operated in the receive mode, and as the carrier frequency generator when the transponder is operated in the transmit mode.