Biomagnetism measurement system for sensing biomagnetic signals

Abstract

A biomagnetic sensor that incorporates an integrated active noise cancellation unit that uses a gradiometer to remove ambient magnetic noise from a detection signal obtained from a tunnelling magnetoresistive (TMR) sensor unit that is indicative of a magnetic field adjacent to biological tissue. The ambient magnetic noise can thus be removed in real time at a front end of the sensor (e.g. as part of circuitry in the sensor body itself). The active noise cancellation technique proposed herein may be effective enough to enable the biomagnetic sensor to be used in an unshielded environment (i.e. an environment that is subject to the Earth's magnetic field, for example), which widens significantly the potential uses for the sensor.

Dependencies are inferred from the claim text.