Adapative telemetry system and method for an implantable medical device

Abstract

A system and method for transmitting telemetry data from an implantable medical device to an external device. A connection-oriented protocol is used to transmit data at a higher data rate while a burst mode protocol is used to transmit data a lower data rate. The lower data rate may be used for remote communications where the received signal is of lower power.

What is claimed is:  
     
         1 . A method for transmitting telemetry data from an implantable medical device, comprising: 
 transmitting data from the implantable device to an external device at either a higher or lower data rate;    wherein data is transmitted at the lower rate using a burst mode telemetry protocol; and,    wherein data is transmitted at the higher rate using a connection-oriented telemetry protocol.    
     
     
         2 . The method of  claim 1  wherein the connection-oriented telemetry protocol dictates that transmitted data packets are acknowledged by the external device and retransmitted the transmitted data packets are unacknowledged.  
     
     
         3 . The method of  claim 1  wherein the burst mode telemetry protocol dictates that transmitted data packets are sent autonomously with no provision for data acknowledgement.  
     
     
         4 . The method of  claim 1  wherein data is transmitted at the lower rate with a lower symbol rate and narrower bandwidth than at the high rate.  
     
     
         5 . The method of  claim 3  wherein data is transmitted to the external device by modulating a radio-frequency carrier signal.  
     
     
         6 . The method of  claim 4  further comprising receiving the modulated carrier signal at the external device and bandpass filtering the signal with a wider or narrower passband depending upon whether the signal contains data transmitted at the higher or lower rate, respectively.  
     
     
         7 . The method of  claim 1  further comprising transmitting data at the lower rate upon a request for data transmission at that rate from the external device.  
     
     
         8 . The method of  claim 1  wherein the connection-oriented protocol is a master/slave protocol in which communications are initiated by a data request from the external device to the implantable medical device.  
     
     
         9 . A telemetry system for an implantable medical device, comprising; 
 circuitry at the implantable device and at one or more external devices for transmitting and receiving data in the form of a modulated carrier signal;    wherein the implantable device is configured to transmit data the external device at either a higher or lower data rate;    wherein data is transmitted at the lower rate using a burst mode telemetry protocol; and,    wherein data is transmitted at the higher rate using a connection-oriented telemetry protocol.    
     
     
         10 . The system of  claim 9  wherein data is transmitted at the lower rate with a lower symbol rate and narrower bandwidth than at the high rate.  
     
     
         11 . The system of  claim 10  wherein data is transmitted to the external device by modulating a radio-frequency carrier signal.  
     
     
         12 . The system of  claim 9  further comprising an external device with a bandpass filter having a passband for receiving signals containing data transmitted at the higher data rate and an external device with a bandpass filter having a passband for receiving signals containing data transmitted at the lower data rate.  
     
     
         13 . The system of  claim 9  wherein the implantable device is configured to transmit data at the lower rate upon a request for data transmission at that rate from the external device.  
     
     
         14 . The system of  claim 9  wherein the connection-oriented telemetry protocol dictates that transmitted data packets are acknowledged by the external device and retransmitted the transmitted data packets are unacknowledged.  
     
     
         15 . The system of  claim 9  wherein the burst mode telemetry protocol dictates that transmitted data packets are sent autonomously with no provision for data acknowledgement.  
     
     
         16 . The system of  claim 9  wherein the connection-oriented protocol is a master/slave protocol in which communications are initiated by a data request from the external device to the implantable medical device.  
     
     
         17 . The system of  claim 9  wherein the implantable device further comprises a pair of bandpass filters with narrower and wider passbands for receiving signals transmitted at the lower and higher data rates, respectively.