# US 10,119,837 B2 · Magnetic-field generating circuit for a tracking system

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,119,837 B2
- Document ID: US10119837B2
- Status: Granted
- Kind: B2
- Application number: 15/202,705
- Filed: 2016-07-06
- Published: 2018-01-11
- Granted: 2018-11-06
- Earliest claimed: 2016-07-06
- Assignees: Biosense Webster (Israel) Ltd.
- Applicants: Biosense Webster (Israel) Ltd.
- Inventors: Vadim Gliner; Yaron Ephrath; Alon Boumendil
- Web page: https://patentgrep.com/patent/US10119837B2

## CPC

- G01D 5/20: by varying inductance, e.g. by a movable armature
- A61B 5/062: {using magnetic field}
- A61B 5/743: {Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots}
- A61B 34/20: Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
- A61B 18/1492: {having a flexible, catheter-like structure, e.g. for heart ablation (A61B18/1477 takes precedence)}
- A61B 2018/0022: {Balloons}
- A61B 2018/00375: {Ostium, e.g. ostium of pulmonary vein or artery}
- A61B 2018/00577: {Ablation}
- A61B 2034/2051: {Electromagnetic tracking systems}
- G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D)

## Abstract

Described embodiments include apparatus that includes a signal generator and an electric circuit. The signal generator is configured to supply a signal having both a first dominant frequency and a second dominant frequency. The electric circuit, which includes a reactive component, is configured to generate, upon the signal being supplied to the electric circuit, a magnetic field having both the first dominant frequency and the second dominant frequency, by virtue of the reactive component simultaneously resonating at both the first dominant frequency and the second dominant frequency. Other embodiments are also described.

## Claims

### Claim 1

An apparatus, comprising:
a signal generator, configured to supply a signal having both a first dominant frequency and a second dominant frequency; and
an electric circuit, comprising a reactive component, configured to generate, upon the signal being supplied to the electric circuit, a magnetic field having both the first dominant frequency and the second dominant frequency, by virtue of the reactive component simultaneously resonating at both the first dominant frequency and the second dominant frequency,
wherein the reactive component is a first inductor, and wherein the electric circuit further comprises:
a first capacitor, connected in series with the first inductor;
a second inductor, connected in parallel with the first inductor; and
a second capacitor, connected in parallel with the first inductor and in series with the second inductor,
wherein the first capacitor and the first inductor are configured to resonate, collectively, at the first dominant frequency, and
wherein the second capacitor, the first inductor, and the second inductor are configured to resonate, collectively, at the second dominant frequency, and
wherein the first capacitor is configured to have an impedance having a magnitude of less than 20 Ohm at the second dominant frequency, and the second capacitor is configured to have an impedance having a magnitude of greater than 1000 Ohm at the first dominant frequency.

### Claim 2

An apparatus, comprising:
a signal generator, configured to supply a signal having both a first dominant frequency and a second dominant frequency; and
an electric circuit, comprising a reactive component, configured to generate, upon the signal being supplied to the electric circuit, a magnetic field having both the first dominant frequency and the second dominant frequency, by virtue of the reactive component simultaneously resonating at both the first dominant frequency and the second dominant frequency,
wherein a difference between the first dominant frequency and the second dominant frequency is at least 5 kHz, and
wherein the first dominant frequency is less than 5 kHz, and the second dominant frequency is greater than 15 kHz.

### Claim 3

An apparatus, comprising:
a signal generator, configured to supply a signal having both a first dominant frequency and a second dominant frequency; and
an electric circuit, comprising a reactive component, configured to generate, upon the signal being supplied to the electric circuit, a magnetic field having both the first dominant frequency and the second dominant frequency, by virtue of the reactive component simultaneously resonating at both the first dominant frequency and the second dominant frequency,
at least one first sensor, configured to generate a first signal in response to sensing the magnetic field at the first dominant frequency; and
at least one second sensor, configured to generate a second signal in response to sensing the magnetic field at the second dominant frequency, and
an intrabody tool comprising the first sensor.

### Claim 4

A method, comprising the steps of:
using a signal generator, supplying, to an electric circuit that includes a reactive component, a signal having both a first dominant frequency and a second dominant frequency;
using the electric circuit, generating, upon the signal being supplied to the electric circuit, a magnetic field having both the first dominant frequency and the second dominant frequency, by virtue of the reactive component simultaneously resonating at both the first dominant frequency and the second dominant frequency;
using at least one first sensor, generating a first signal in response to sensing the magnetic field at the first dominant frequency;
using at least one second sensor, generating a second signal in response to sensing the magnetic field at the second dominant frequency; and
in response to the first signal and the second signal, ascertaining respective locations of the first sensor and the second sensor.

### Claim 5 (depends on 4)

The method according to claim 4, wherein using the first sensor to generate the first signal comprises using the first sensor to generate the first signal while the first sensor is inside a body of a subject.

### Claim 6 (depends on 5)

The method according to claim 5, wherein generating the magnetic field comprises generating the magnetic field from beneath the subject.

### Claim 7

A method, comprising the steps of:
using a signal generator, supplying, to an electric circuit that includes a reactive component, a signal having both a first dominant frequency and a second dominant frequency;
using the electric circuit, generating, upon the signal being supplied to the electric circuit, a magnetic field having both the first dominant frequency and the second dominant frequency, by virtue of the reactive component simultaneously resonating at both the first dominant frequency and the second dominant frequency;
wherein a difference between the first dominant frequency and the second dominant frequency is at least 5 kHz, and
wherein the first dominant frequency is less than 5 kHz, and the second dominant frequency is greater than 15 kHz.