Vitalcom, Inc.

Ge Medical Systems Information Technologies Gmbh

Powerwave Cognition, Inc.

Pacific Communications

Terry E Flach

Michael D Stoop

Timothy J Hughes

James S Tsusaki

Kurt I Winckler

Rita R Rabbath

William C McBride

Presently disclosed are a multichannel receiver and a method of operating it. The multichannel receiver includes a first channel circuit of N channel circuits. The first channel circuit includes a band pass (BP) filter and a gain control feedback circuit configured to adjust a signal provided by the BP filter with respect to a reference voltage.

Multiple signal receiving

In one aspect, the invention is a multichannel receiver. The multichannel receiver includes a first channel circuit of N channel circuits. The first channel circuit includes a band pass (BP) filter and a gain control (GC) feedback circuit configured to adjust a signal provided by the BP filter with respect to a reference voltage.

A real time patient monitoring system uses a cellular architecture to monitor ECG signals and other physiologic data of patients, including ambulatory patients. The system includes wireless telemeters that attach to and transmit the physiologic data of respective patients. The telemeters communicate bi-directionally with ceiling-mounted RF transceivers, referred to as &ldquo;VCELLs,&rdquo; using a wireless TDMA protocol. The VCELLs forward packets of physiologic data received from the telemeters to patient monitoring stations on a LAN. The VCELLs are spatially distributed throughout the medical facility to provide multiple cells or zones of coverage. As a patient moves throughout the medical facility, the patient's telemeter connects to, and disconnects from, specific VCELLs to maintain connectivity to the LAN. The telemeters and VCELLs also implement a patient location tracking process for monitoring of the locations of individual patients.

Cellular architecture and data transfer methods for real time patient monitoring within medical facilities

A medical telemetry system is provided for collecting the real-time physiologic data of patients (including ambulatory patients) of a medical facility, and for transferring the data via RF to a real-time data distribution network for monitoring and display. The system includes battery-powered remote telemeters which attach to respective patients, and which collect and transmit (in data packets) the physiologic data of the patients. The remote telemeters communicate bi-directionally with a number of ceiling-mounted RF transceivers, referred to as &ldquo;VCELLs,&rdquo; using a wireless TDMA protocol. The VCELLs, which are hardwire-connected to a LAN, forward the data packets received from the telemeters to patient monitoring stations on the LAN. The VCELLs are distributed throughout the medical facility such that different VCELLs provide coverage for different patient areas. As part of the wireless TDMA protocol, the remote telemeters continuously assess the quality of the RF links offered by different nearby VCELLs (by scanning the frequencies on which different VCELLs operate), and connect to those VCELLs which offer the best link conditions. To provide a high degree of protection against multi-path interference, each remote telemeter maintains connections with two different VCELLs at-a-time, and transmits all data packets (on different frequencies and during different timeslots) to both VCELLs; the system thereby provides space, time and frequency diversity on wireless data packet transfers from the telemeters. The telemeters and VCELLs also implement a patient location protocol for enabling the monitoring of the locations of individual patients. The architecture can accommodate a large number of patients (e.g., 500 or more) while operating within the transmission power limits of the VHF medical telemetry band.

Medical telemetry system with cellular reception of patient data

Telemeter design and data transfer methods for medical telemetry system

A medical telemetry system is provided for collecting the real-time physiologic data of patients (including ambulatory patients) of a medical facility, and for transferring the data via RF to a real-time data distribution network for monitoring and display. The system includes battery-powered remote telemeters which attach to respective patients, and which collect and transmit (in data packets) the physiologic data of the patients. The remote telemeters communicate bi-directionally with a number of ceiling-mounted RF transceivers, referred to as 'VCELLs,' using a wireless TDMA protocol. The VCELLs, which are hardwire-connected to a LAN, forward the data packets received from the telemeters to patient monitoring stations on the LAN. The VCELLs are distributed throughout the medical facility such that different VCELLs provide coverage for different patient areas. As part of the wireless TDMA protocol, the remote telemeters continuously assess the quality of the RF links offered by different nearby VCELLs (by scanning the frequencies on which different VCELLs operate), and connect to those VCELLs which offer the best link conditions. To provide a high degree of protection against multi-path interference, each remote telemeter maintains connections with two different VCELLs at-a-time, and transmits all data packets (on different frequencies and during different timeslots) to both VCELLs; the system thereby provides space, time and frequency diversity on wireless data packet transfers from the telemeters. The telemeters and VCELLs also implement a patient location protocol for enabling the monitoring of the locations of individual patients. The architecture can accommodate a large number of patients (e.g., 500 or more) while operating within the transmission power limits of the VHF medical telemetry band.

Architecture for TDMA medical telemetry system

A two-way medical telemetry system is provided for displaying and monitoring, at a central location, physiologic and other patient data of multiple, remotely-located patients. The system comprises multiple battery-powered remote telemeters, each of which is worn by a respective patient, and a central station which receives, displays and monitors the patient data received (via RF) from the remote telemeters. The telemeters communicate with the central station using a two-way TDMA protocol which permits the time sharing of timeslots, and which uses a contention slot to permit telemeters to transmit service requests to the central station. Two-way spacial diversity is provided using only one antenna and one transceiver on each remote telemeter. The remote telemeters include circuitry for turning off the active transceiver components thereof when not in use (to conserve battery power), and include circuitry for performing a rapid, low-power frequency lock cycle upon power-up. The system has multiple modes of operation, including a frequency hopping (spread spectrum) mode and a fixed frequency mode, both of which preferably make use of the 902-928 MHz ISM band. Patient locators are provided to allow the clinician to track the location of each patient.

Low-power circuit and method for providing rapid frequency lock in a

Two-way TDMA telemetry system with power conservation features

Biomedical information is directly digitally telemetered from the patient through a frequency modulated transmitter to a remote receiver and computer station. A phase-lock-loop circuit in the digital transmitter compensates for DC data bias by averaging and generating a scaled measure of the DC content of the digital data fed into the phase-lock-loop circuit. The average signal is then provided as a control signal to a first voltage controlled crystal oscillator, the output of which is then used as a reference frequency for the phase-lock-loop circuit. Frequency modulation of the digital data is provided by coupling the digital data directly into the voltage control input of the voltage controlled oscillator which generates the output frequency. Further control of the phase-lock-loop circuit in the transmitter is achieved by prepositioning the operating frequency of the voltage controlled oscillator by means of a microcontroller. The input to the microcontroller is a digital word corresponding to the desired frequency. The microcontroller then uses an algorithm to set the operating frequency of the voltage controlled oscillator at a preselected point within the bandwidth of the phase-lock-loop circuit. The operating point of the phase-lock-loop circuit is set by a first varactor diode while fine tuning of the voltage controlled oscillator is provided by a second varactor diode. The operating point of the voltage controlled oscillator is set in such a position of the tuning curve of the voltage controlled oscillator that the gain of the oscillator approximately compensates for any changes in the dividing integer used in a divider in the phase-lock-loop circuit.

Phase-lock-loop circuit and method for compensating, data bias in the

Biomedical information is directly digitally telemetered from the patient through a frequency modulated transmitter to a remote receiver and computer station. DC offset on the biopotential leads and signals from the patient is compensated by converting the output of the amplifier, such as an electrocardiographic amplifier, into digital format, determining the average or DC component of the digital signal, and generating a digital correction word which is then converted into analog form and fed back into the input of the electrocardiographic amplifier to cancel out the DC offset. The same circuitry is used to insert a standard test signal instead of a correction signal and the output of the amplifier is then checked not to determine its DC component, but to determine whether or not the gain of the electrocardiographic amplifier is performing at a predetermined calibration point. If not, a digital correction word is generated and provided as a correction signal to the programmable gain amplifier.

Growing community of inventors

Altadena, CA, United States of America

Terry E Flach