System and methods for triggering a radiofrequency transceiver in the human body
Systems and methods described herein use near field communications to locate a radiating transponder, such as a pill swallowed by a patient. The system can be triggered to turn on and transmit a waveform to a set of antennas attached to, coupled with, or near the patient. The magnetic field emitted by the transponder can be measured by the receiving antennas, for example, using principles of mutual inductance. The differential phase and/or time shifts between the antennas can contain sufficient information to find the location of the transponder and optionally its orientation relative to body coordinates. The system can display the location and/or orientation of the transponder. Further, the pill can include a reservoir to deliver a payload at a particular site of the patient's body based at least in part on the determined location.
1. A system for locating and triggering a patient-swallowed pill transmitter, the system comprising:
processing electronics configured to:
receive signals from a plurality of antennas disposed about a body of a patient, the signals responsive to a transmitted signal from a pill transmitter swallowed by the patient;
identify phase differences and amplitude shifts associated with the received signals;
compare the phase differences and the amplitude shifts with a stored training set, wherein the stored training set comprises measurements of phase measurements and amplitude measurements of a pill transmitting outside of the patient at various selected locations in a volume surrounded by the plurality of antennas, wherein the plurality of antennas are positioned on a frame to approximately correspond to locations of the plurality of antennas on the body of the patient;
estimate a location of the pill transmitter within the body of the patient based at least in part on the comparison of the phase differences and the amplitude shifts with the stored training set; and
refine the estimated location of the pill transmitter by applying a nonlinear process to the estimated location to produce a refined estimated location of the pill transmitter;
a memory device comprising physical memory hardware, the memory device configured to store the refined estimated location of the pill transmitter; and
a display configured to output the refined estimated location of the pill transmitter.
2. The system of claim 1 , wherein the processing electronics are further configured to: receive a user input indicating to activate a component of the pill transmitter at a specified location.
3. The system of claim 2 , wherein the processing electronics are further configured to:
compare the specified location with the estimated location;
responsive to said comparison, wirelessly transmit a trigger signal to the pill transmitter, said trigger signal configured to activate the component of the pill transmitter.
4. The system of claim 1 , wherein the user input comprises an indication from a clinician to dispense medication in the body of the patient at or near the refined estimated location of the pill.
5. The system of claim 1 , wherein said estimating the location of the pill transmitter comprises:
filtering the refined estimated location of the pill transmitter to produce an overall estimate of the location of the pill transmitter based at least in part on previously estimated location of the pill transmitter within the body of the patient.
6. A system for locating and triggering a patient-swallowed pill transmitter, the system comprising:
processing electronics configured to:
receive signals from a plurality of antennas disposed about a body of a patient, the signals responsive to a transmitted signal from a pill transmitter swallowed by the patient;
identify phase difference associated with the received signals;
compare the phase differences with a stored training set, wherein the stored training set comprises measurements of phase measurements of a pill outside of the patient at various selected locations in a volume surrounded by the plurality of antennas, wherein the plurality of antennas are positioned on a frame to approximately correspond to locations of the plurality of antennas on the body of the patient;
estimate a location of the pill transmitter within the body of the patient based on the comparison of the phase differences with the stored training set; and
a memory device comprising physical memory hardware, the memory device configured to store the estimated location of the pill transmitter; and
a display configured to depict the estimated location of the pill transmitter.
7. The system of claim 6 , wherein the processing electronics are further configured to:
output an indication of the estimated location of the pill transmitter;
receive an input from a user interface corresponding to activating a feature of the pill; and
transmit a trigger signal to the pill transmitter based in part on the received input to cause the pill transmitter to activate the feature.
8. The system of claim 7 , wherein said indication of the location comprises a graphical representation of the location of the pill with respect to the body of the patient.
9. The system of claim 7 , wherein the trigger signal comprises a coded message.
10. The system of claim 7 , wherein the trigger signal is configured to cause the pill transmitter to dispense medication.
11. The system of claim 6 , wherein said estimating the location of the pill transmitter further comprises:
filtering the refined estimated location of the pill transmitter to produce an overall estimate of the location of the pill transmitter based at least in part on previously estimated location of the pill transmitter within the body of the patient.