Sensing and wireless communications for implantable biomedical devices

Abstract

A sensor system has a first tag including a first communication circuit, and a second tag including a second communication circuit. The first tag is operative to initiate a first wireless transmission for reception by the second tag, the wireless transmission pertaining to a measurement effected by the first tag or the second tag. The second tag is operative to wirelessly communicate data representing the measurement to a reader device.

What is claimed is: 
     
         1 . A sensor system, comprising:
 a first tag including a first communication circuit, and a first encapsulation structure enclosing the first communication circuit; and   a second tag including a second communication circuit and a second encapsulation structure enclosing the second communication circuit;   
       wherein the first tag and the second tag are each operative such that:
 the first tag is to initiate a first wireless transmission for reception by the second tag, the wireless transmission pertaining to a measurement effected by the first tag or the second tag; and 
 the second tag is to wirelessly communicate data representing the measurement to a reader device. 
 
     
     
         2 . The sensor system of  claim 1 , wherein the first tag comprises a detector tag that comprises a sensing transducer circuit operative to take measurements of an environment surrounding the detector tag, and wherein the first wireless transmission includes data representing the measurement. 
     
     
         3 . The sensor system of  claim 2 , wherein the second tag is a collector tag operative to store the data representing the measurement and to incorporate the data into a second wireless transmission for reception by the reader. 
     
     
         4 . The sensor system of  claim 3 , wherein the first wireless transmission is in a first radio-frequency band, and wherein the second wireless transmission is in a second radio-frequency band that is different from the first radio-frequency band. 
     
     
         5 . The sensor system of  claim 3 , wherein the first tag and the second tag are each adapted for implantation inside an animal, and wherein second wireless transmission is a transcutaneous signal. 
     
     
         6 . The sensor system of  claim 1 , wherein the first wireless transmission by the first tag is a sense-stimulation signal, and wherein the second tag is operative to measure a signal property of the sense-stimulation signal to take the measurement. 
     
     
         7 . The sensor system of  claim 6 , wherein the sense-stimulation signal includes a first frequency component and a second frequency component, and wherein the signal property measured by the second tag includes a change in relative signal strength between the first frequency component and the second frequency component. 
     
     
         8 . The sensor system of  claim 1 , wherein the second tag is operative to store a plurality of measurements including said measurement. 
     
     
         9 . The sensor system of  claim 8 , wherein the second tag is operative to aggregate the plurality of measurements into an aggregated set, wherein the aggregated set represents said measurement, and wherein the second tag is operative to communicate the aggregated set to the reader device. 
     
     
         10 . The sensor system of  claim 1 , wherein the first tag and the second tag are operatively arranged in a spaced relationship. 
     
     
         11 . The sensor system of  claim 1 , wherein the first tag is operative to store energy from a wireless interrogation signal transmitted by a reader device and to utilize the stored energy to effect operation of the first tag; and
 wherein the second tag is operative to store energy from the wireless interrogation signal transmitted by a reader device and to utilize that stored energy to effect operation of the second tag.   
     
     
         12 . A method for operating a sensor system that includes a first tag having a first communication circuit and a second tag including a second communication circuit, the method comprising:
 initiating, by the first tag, a first wireless transmission for reception by the second tag, the wireless transmission pertaining to a measurement effected by the first tag or the second tag; and   wirelessly communicating, by the second tag, data representing the measurement to a reader device.   
     
     
         13 . The method of  claim 12 , further comprising:
 taking a measurement, by a sensing transducer circuit of the first tag, of an environment surrounding the first tag, and wherein initiating the first wireless transmission includes initiating transmission of data representing the measurement.   
     
     
         14 . The method of  claim 13 , further comprising:
 storing, by the second tag, the data representing the measurement; and   initiating a second wireless transmission for reception by the reader, the second wireless transmission including the data.   
     
     
         15 . The method of  claim 14 , wherein the first wireless transmission is transmitted in a first radio-frequency band, and wherein the second wireless transmission is transmitted in a second radio-frequency band that is different from the first radio-frequency band. 
     
     
         16 . The method of  claim 14 , wherein the first tag and the second tag are each implanted inside an animal, and wherein second wireless transmission is a transcutaneous signal. 
     
     
         17 . The method of  claim 12 , wherein the first wireless transmission by the first tag is a sense-stimulation signal, and wherein the method further comprises:
 measuring, by the second tag, a signal property of the sense-stimulation signal to take the measurement.   
     
     
         18 . The method of  claim 17 , wherein the sense-stimulation signal includes a first frequency component and a second frequency component, and wherein the measuring the signal property measured by the second tag includes measuring a change in relative signal strength between the first frequency component and the second frequency component. 
     
     
         19 . The method of  claim 12 , further comprising:
 storing, by the second tag, a plurality of measurements including said measurement; and   aggregating, by the second tag, the plurality of measurements into an aggregated set, wherein the aggregated set represents said measurement; and   communicating, by the second tag, the aggregated set to the reader device.   
     
     
         20 . The method of  claim 12 , further comprising:
 storing, by the first tag, energy from a wireless interrogation signal transmitted by a reader device, and utilizing the stored energy to effect operation of the first tag; and   storing, by the second tag, energy from the wireless interrogation signal transmitted by a reader device, and utilizing that stored energy to effect operation of the second tag.