System and method for acoustic information exchange involving an ingestible low power capsule

Abstract

A method of communicating with an ingestible capsule includes detecting the location of the ingestible capsule, focusing a multi-sensor acoustic array on the ingestible capsule, and communicating an acoustic information exchange with the ingestible capsule via the multi-sensor acoustic array. The ingestible capsule includes a sensor that receives a stimulus inside the gastrointestinal tract of an animal, a bidirectional acoustic information communications module that transmits an acoustic information signal containing information from the sensor, and an acoustically transmissive encapsulation that substantially encloses the sensor and communications module, wherein the acoustically transmissive encapsulation is of ingestible size. The multi-sensor array includes a plurality of acoustic transducers that receive an acoustic signal from a movable device, and a plurality of delays, wherein each delay is coupled to a corresponding acoustic transducer. Each delay may be adjusted according to a phase of a signal received by the corresponding acoustic transducer.

1 .- 9 . (canceled) 
     
     
         10 . A sensor array configured to communicate with a movable object, comprising:
 a plurality of acoustic transducers configured to receive an acoustic signal from the movable object; and   a plurality of delays, each delay coupled to a corresponding one of the plurality of acoustic transducers,   wherein each delay is adjusted according to a phase of an information signal received by the corresponding acoustic transducer.   
     
     
         11 . The sensor array of  claim 10 , wherein the acoustic transducers are spaced apart by approximately one-half the wavelength of the received information signal. 
     
     
         12 . The sensor array of  claim 10 , wherein each acoustic transducer has a width approximately equal to one-quarter the wavelength of the received information signal. 
     
     
         13 . The sensor array of  claim 10 , wherein each delay is determined through a successive approximation. 
     
     
         14 . An ingestible capsule, comprising:
 a sensor that receives a stimulus inside the gastrointestinal tract of an animal;   a bi-directional acoustic information communications module that transmits an acoustic information signal containing information from the sensor; and   an acoustically transmissive encapsulation configured to have a size that is ingestible, wherein the acoustically transmissive encapsulation substantially encloses the sensor and communications module.   
     
     
         15 . The device of  claim 14 , the communications module comprising:
 a receiver that receives an acoustic information signal;   a modulator that modulates a carrier frequency with the sensor output signal to generate an acoustic information signal;   a transmitter that transmits an acoustic information signal generated by the modulator.   
     
     
         16 . The device of  claim 14 , the communications module comprising:
 a radiating element coupled to an output of the communications module.   
     
     
         17 . The device of  claim 16 , wherein the radiating element is a piezoelectric element. 
     
     
         18 . The device of  claim 17 , wherein the radiating element is two or more piezoelectric elements spaced apart by a distance that is half the wavelength of the modulated signal. 
     
     
         19 . The device of  claim 17 , wherein the radiating element emits a locationing signal that allows a detector to locate the device. 
     
     
         20 . The device of  claim 14 , wherein the communications module is configured to suspend transmission of the acoustic information signal while information is obtained by the sensor. 
     
     
         21 . The device of  claim 14 , wherein the communications module is configured to transmit an acoustic locationing signal prior to transmission of the acoustic information signal. 
     
     
         22 . The device of  claim 14 , wherein the communications module is configured to transmit and receive an electromechanically modulated acoustic information signal. 
     
     
         23 . A method of transmitting information acoustically, comprising:
 applying a base voltage to a piezoelectric device to cause the piezoelectric device to ring at a drone frequency;   applying a voltage higher than the base voltage to the piezoelectric device to cause the piezoelectric device to ring at a first frequency that is different from the drone frequency; and   applying a voltage lower than the base voltage to the piezoelectric device to cause the piezoelectric device to ring at a second frequency that is different from the first frequency and the drone frequency,   wherein the first frequency represents a “1” bit and the second frequency represents a “0” bit in the transmitted information signal.   
     
     
         24 . The method of  claim 23 , further comprising:
 receiving information to be modulated into a transmitted information signal; and   applying a higher voltage and a lower voltage in sequence to generate the transmitted information signal.   
     
     
         25 . The method of  claim 23 , wherein the base voltage is applied to separate bits in the transmitted information signal.