Patent US1881450A successfully refreshed from Google Patents.
US4977896A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Analysis of biological signals using data from arrays of sensors
Assignee: Biomagnetic Technologies Inc
•
Filing: 1989-05-26
•
Granted: 1990-12-18
•
Expires: 2009-05-26
Abstract
Abstract Signals produced by brain activity are measured by each sensor of an array of magnetic and/or electrical sensors external to but proximate to the head (or other portion of the body) of a subject. The measurements obtained simultaneously from all of the sensors are combined in a manner to permit selective measurement of the electrical activity from a specified location within the body, or alternatively, to permit the location in the body producing a particular type of response to be identified. The instantaneous measurement of each sensor is scaled by a weighting coefficient for that sensor, and the products added over all of the sensors. The weighting coefficients are calculated from a mathematical model of the brain that includes information on the shape of the potential source, the extent or type of source activity, the electrical and magnetic properties of the media, and the locations and orientations of the sources and the sensors.
Inventors
- 👤 Stephen E. Robinson
- 👤 William C. Black, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:02
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/24; A61B5/242
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
111 words
A process for sensing and evaluating signals emanating from the brain of a subject, comprising the steps of: providing an array of magnetic field sensors disposed external to a head of said subject at known locations; measuring a signal strength detected by each of said sensors; multiplying the signal strength measured by each of said sensors times a weighting coefficient for that sensor selected to focus the sensitivity of the array of said field sensors on a selected location in the brain, to determine a virtual sensor contribution for each of said sensors; and adding together the virtual sensor contribution of each of said sensors, to define a virtual sensor signal.
Claim 2
Dependent Claim
111 words
A process for sensing and evaluating signals emanating from the brain of a subject, comprising the steps of: providing an array of magnetic field sensors disposed external to a head of said subject at known locations; measuring a signal strength detected by each of said sensors; multiplying the signal strength measured by each of said sensors times a weighting coefficient for that sensor selected to focus the sensitivity of the array of said field sensors on a selected location in the brain, to determine a virtual sensor contribution for each of said sensors; and adding together the virtual sensor contribution of each of said sensors, to define a virtual sensor signal.
Claim 3
Dependent Claim
16 words
The process of claim 1, wherein each of said sensors includes a superconducting quantum interference device.
Claim 4
Dependent Claim
24 words
The process of claim 1, including, after the step of adding, the additional step of: correlating the virtual sensor signal with a physiological activity.
Claim 5
Dependent Claim
93 words
A process for sensing and evaluating signals emanating from a body of a subject, comprising the steps of: measuring a signal strength detected by each sensor of an array of electromagnetic sensors placed proximately to said body of a subject; and calculating a virtual sensor signal for the array, as a sum, over all of said sensors, of a product of a weighting coefficient for each said sensor times the signal measured for that sensor, the weighting coefficients being selected to focus the array of sensors on a selected location in the body.
Claim 6
Dependent Claim
93 words
A process for sensing and evaluating signals emanating from a body of a subject, comprising the steps of: measuring a signal strength detected by each sensor of an array of electromagnetic sensors placed proximately to said body of a subject; and calculating a virtual sensor signal for the array, as a sum, over all of said sensors, of a product of a weighting coefficient for each said sensor times the signal measured for that sensor, the weighting coefficients being selected to focus the array of sensors on a selected location in the body.
Claim 7
Dependent Claim
38 words
The process of claim 4, wherein the weighting coefficient for each of said sensors is selected to optimize a contribution to a virtual signal of a selected target source relative to signals not produced by that target source.
Claim 8
Dependent Claim
17 words
The process of claim 4, wherein the sensors are placed proximately to a head of the subject.
Claim 9
Dependent Claim
17 words
The process of claim 4, wherein the sensors are placed proximately to a chest of the subject.
Claim 10
Dependent Claim
167 words
A process for sensing and evaluating electromagnetic signals emanating from a body of a subject, comprising the steps of: providing an array of electromagnetic field sensors disposed external to a body of a subject at known locations; determining a weighting coefficient applicable to each of said sensors, the step of determining including the steps of characterizing a geometry of the body, characterizing a nature of the magnetic fields emanating from possible sources in the body, characterizing a medium through which the magnetic fields propagate, formulating a mathematical model of the response of said sensors to a source within the body, and calculating each of said weighting coefficients from the model; measuring the signal strength detected by each of said sensors; multiplying the signal strength measured by each of said sensors times the calculated weighting coefficient for that sensor to determine a virtual sensor contribution for each of said sensors; and adding together said virtual sensor contributions of each of said sensors, to define a virtual sensor signal.
Claim 11
Dependent Claim
167 words
A process for sensing and evaluating electromagnetic signals emanating from a body of a subject, comprising the steps of: providing an array of electromagnetic field sensors disposed external to a body of a subject at known locations; determining a weighting coefficient applicable to each of said sensors, the step of determining including the steps of characterizing a geometry of the body, characterizing a nature of the magnetic fields emanating from possible sources in the body, characterizing a medium through which the magnetic fields propagate, formulating a mathematical model of the response of said sensors to a source within the body, and calculating each of said weighting coefficients from the model; measuring the signal strength detected by each of said sensors; multiplying the signal strength measured by each of said sensors times the calculated weighting coefficient for that sensor to determine a virtual sensor contribution for each of said sensors; and adding together said virtual sensor contributions of each of said sensors, to define a virtual sensor signal.
Claim 12
Dependent Claim
43 words
The process of claim 8, wherein the calculated weighting coefficient for each of said sensors is selected using the mathematical model to optimize a contribution to the virtual signal of a selected target source, relative to signals not produced by the target source.
Claim 13
Dependent Claim
23 words
The process of claim 8, including, after the step of adding, the additional step of: correlating the virtual sensor signal with physiological information.
Claim 14
Dependent Claim
16 words
The process of claim 8, wherein each of said sensors includes a superconducting quantum interference device.
Claim 15
Dependent Claim
14 words
The process of claim 8, wherein the mathematical model is a finite mesh model.
Claim 16
Dependent Claim
19 words
The process of claim 8 wherein each of said sensors is placed proximately to a head of the subject.
Claim 17
Dependent Claim
19 words
The process of claim 8, wherein each of said sensors is placed proximately to a chest of the subject.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-17 | 1994-06-18 | 1994-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-17 | 1998-06-18 | 1998-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-17 | 2002-06-18 | 2002-12-18 | $7700.00 | Window Closed / Lapsed |