HAND-HELD DUAL SPHERICAL ANTENNA SYSTEM

• US 20160259954A1
• Filed: 02/24/2016
• Published: 09/08/2016
• Est. Priority Date: 03/02/2015
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Buhler, John T., Blair, William A., Poirier, David A., Crump, Curtis
• Granted Patent: US 9,690,963 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2090/0804 Counting number of instruments used; Instrument detectors
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61B 90/98 using electromagnetic means, e.g. transponders
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10386 the interrogation device being of the portable or hand-handheld type, e.g. incorporated in ubiquitous hand-held devices such as PDA or mobile phone, or in the form of a portable dedicated RFID reader
• CPC Class Codes: H01F 2005/027 wound on formers for receiving several coils with perpendicular winding axes, e.g. for antennae or inductive power transfer
• CPC Class Codes: H01Q 1/2208 associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

A hand-held antenna system allows medical personnel to ascertain the presence or absence of objects (e.g., medical supplies) tagged with transponders in an environment in which medical procedures are performed. In use, the hand-held antenna system may be positioned proximate a patient at a time after a medical procedure, such as after childbirth, so the system can scan the patient'"'"'s body to determine the presence of objects tagged with transponders. The antenna system includes two sets of three antenna elements arranged mutually orthogonal to each other to transmit and receive signals in at least three coordinate directions. A controller is coupled to the antenna elements to transmit signals to the transponders and to receive response signals. The antenna system may operate in a static scan mode wherein the antenna system is held in a fixed position by a user and a dynamic scan mode wherein the antenna system is moved by a user.

Claims

1. A transponder detection device to detect surgical objects in a work area, the surgical objects marked by respective resonant tag elements that produce return signals in response to energization, the transponder detection device comprising:

a hand-held probe comprising;

a housing having a cavity therein; and

a first coil assembly and a second coil assembly received within the cavity of the housing spaced from each other, wherein each of the first and the second coil assemblies respectively includes;

a substantially spherically shaped coil form that includes three coil support channels, each of the three coil support channels which define an outer coil support surface;

a first antenna element comprising a first electrical conductor wound around the outer coil support surface of a first one of the three coil support channels, the first antenna element arranged to transmit and receive signals generally in a first coordinate direction;

a second antenna element comprising a second electrical conductor wound around the outer coil support surface of a second one of the three coil support channels over the first electrical conductor, the second antenna element arranged to transmit and receive signals generally in a second coordinate direction orthogonal to the first coordinate direction; and

a third antenna element comprising a third electrical conductor wound around the outer coil support surface of a third one of the three coil support channels over the first electrical conductor and the second electrical conductor, the third antenna element arranged to transmit and receive signals generally in a third coordinate direction orthogonal to the first coordinate direction and the second coordinate direction.

2. The transponder detection device of claim 1 wherein the cavity of the housing is defined by a first body portion that receives the first coil assembly, a second body portion that receives the second coil assembly, and a handle portion disposed between the first body portion and the second body portion.

3. The transponder detection device of claim 2 wherein the handle portion is disposed between the first body portion and the second body portion to allow the first body portion and the second body portion to at least partially surround a human joint during use.

4. The transponder detection device of claim 1 wherein at least one of the first, the second or the third antenna elements of the first coil assembly is arranged to transmit and receive signals generally in a coordinate direction which is the same as a coordinate direction in which at least one of the first, the second or the third antenna elements of the second coil assembly is arranged to transmit and receive signals.

5. The transponder detection device of claim 1 wherein each of the first, the second and the third antenna elements of the first coil assembly is arranged to transmit and receive signals generally in a coordinate direction which is the same as a coordinate direction in which a different one of the first, the second or the third antenna elements of the second coil assembly is arranged to transmit and receive signals.

6. The transponder detection device of claim 1 wherein at least one of the first, the second or the third antenna elements of the first coil assembly is coplanar with at least one of the first, the second or the third antenna elements of the second coil assembly.

7. The transponder detection device of claim 1 wherein, for each of the respective coil forms of the first and the second coil assemblies, each of the three coil support channels is shaped as a spherical zone of a virtual sphere.

8. The transponder detection device of claim 7 wherein, for each of the respective coil forms of the first and the second coil assemblies, each of the three coil support channels is shaped as a spherical zone of a virtual sphere centered on a great circle of the virtual sphere.

9. The transponder detection device of claim 1 wherein, for each of the respective coil forms of the first and the second coil assemblies, the three coil support channels are shaped as a spherical zone of the substantially spherically shaped coil form centered on respective orthogonal great circles of the coil form.

10. The transponder detection device of claim 1, further comprising:

a light source coupled to the housing that provides a visual indication of at least a status of the transponder detection device.

11. The transponder detection device of claim 1, further comprising:

a processor operatively coupled to the respective first antenna elements, the second antenna elements, and the third antenna elements of the first and the second coil assemblies; and

a nontransitory processor-readable medium communicatively coupled to the processor and that stores at least one of instructions or data executable by the processor, which cause the processor to;

control each of the first antenna elements, the second antenna elements and the third antenna elements of the first and the second coil assemblies to emit wideband interrogation signals;

receive any of the return signals from any of the resonant tag elements; and

determine from a receipt of any of the return signals whether any of the resonant tag elements are present in the work area.

12. The transponder detection device of claim 11 wherein the processor:

controls each of the respective first antenna elements, the second antenna elements and the third antenna elements of the first and the second coil assemblies to emit wideband interrogation signals in time-wise succession during a transmit portion of respective transmit and receive cycles, and controls each of the first antenna elements, the second antenna elements and the third antenna elements of the first and the second coil assemblies to not emit wideband interrogation signals during a receive portion of respective transmit and receive cycles.

13. The transponder detection device of claim 11 wherein the processor further:

receives a selection of at least one of a dynamic scan mode and a static scan mode;

in response to receiving a selection of the static scan mode, controls each of the first antenna elements, the second antenna elements and the third antenna elements to emit wideband interrogation signals according to a static instrument scan cycle having a static instrument scan cycle duration; and

in response to receiving a selection of the dynamic scan mode, controls each of the first antenna elements, the second antenna elements and the third antenna elements to emit wideband interrogation signals according to a dynamic instrument scan cycle having a dynamic instrument scan cycle duration that is less than the static instrument scan cycle duration.

14. The transponder detection device of claim 13 wherein, in response to receiving a selection of the static scan mode, the processor controls each of the first antenna elements, the second antenna elements and the third antenna elements to emit wideband interrogation signals centered on a first frequency, and further controls each of the first antenna elements, the second antenna elements and the third antenna elements to emit wideband interrogation signals centered on a second frequency, the second frequency different from the first frequency.

15. The transponder detection device of claim 11 wherein the processor further:

determines from a receipt of any of the return signals whether any of the resonant tag elements are present in the work area based at least in part on a frequency of the return signals received being within a defined frequency range.

16. The transponder detection device of claim 11 wherein the processor further:

determines whether any of the resonant tag elements are present in the work area based at least in part on a Q value of the return signals received.

17. The transponder detection device of claim 11 wherein the processor further:

receives electromagnetic signals during a noise detection portion;

determines a noise value indicative of a noise level that corresponds to a number of measurements of the electromagnetic signals received during the noise detection portion;

adjusts a signal detection threshold based at least in part on the determined noise value; and

determines whether any of the resonant tag elements are present in the work area based at least in part on a number of measurements of the return signals received and the adjusted signal detection threshold.

18. A method to detect surgical objects in a work area, the surgical objects marked by respective resonant tag elements that produce return signals in response to energization, the method comprising:

providing a transponder detection device that includes a hand-held probe comprising a housing having a cavity therein;

a first coil assembly and a second coil assembly received within the cavity of the housing spaced from each other, wherein each of the first and the second coil assemblies respectively includes;

a substantially spherically shaped coil form that includes three coil support channels, each of the three coil support channels which define an outer coil support surface;

a first antenna element comprising a first electrical conductor wound around the outer coil support surface of a first one of the three coil support channels, the first antenna element arranged to transmit and receive signals generally in a first coordinate direction;

a second antenna element comprising a second electrical conductor wound around the outer coil support surface of a second one of the three coil support channels over the first electrical conductor, the second antenna element arranged to transmit and receive signals generally in a second coordinate direction orthogonal to the first coordinate direction; and

a third antenna element comprising a third electrical conductor wound around the outer coil support surface of a third one of the three coil support channels over the first electrical conductor and the second electrical conductor, the third antenna element arranged to transmit and receive signals generally in a third coordinate direction orthogonal to the first coordinate direction and the second coordinate direction;

emitting wideband interrogation signals via the respective first antenna elements, the second antenna elements and the third antenna elements of the first and the second coil assemblies;

receiving any of the return signals from any of the resonant tag elements via at least one of the respective first antenna elements, the second antenna elements and the third antenna elements of the first and the second coil assemblies; and

determining from a receipt of any of the return signals whether any of the resonant tag elements are present in the work area.

19. The method of claim 18, further comprising:

controlling each of the first antenna elements, the second antenna elements and the third antenna elements to emit wideband interrogation signals in time-wise succession during a transmit portion of respective transmit and receive cycles and controlling each of the first antenna elements, the second antenna elements and the third antenna elements to not emit wideband interrogation signals during a receive portion of respective transmit and receive cycles.

20. The method of claim 18, further comprising:

controlling each of the first antenna elements, the second antenna elements and the third antenna elements to emit wideband interrogation signals according to a static instrument scan cycle having a static instrument scan cycle duration; and

controlling each of the first antenna elements, the second antenna elements and the third antenna elements to emit wideband interrogation signals according to a dynamic instrument scan cycle having a dynamic instrument scan cycle duration that is less than the static instrument scan cycle duration.