Single-core fluxgate gradiometer with simultaneous gradient and homogeneous feedback operation

Micro-fluxgate sensor with closed core

Micro-fluxgate sensor with symmetrical core on both sides of the planar rectangular excitation and pick-up coils has substantially improved parameters compared to its single-core predecessor. Almost closed magnetic path for the excitation field allows much deeper saturation of the sensor core, which reduces the perming effect, hysteresis and noise. Perming of max. 5 μT for 6 mT field shock, 28 ...

Orthogonal Fluxgate Type Magnetic Microsensors with Wide Linear Operation Range

VII

Single Feedback Systkms for Simultaneous

Symmetrical core improves micro-fluxgate sensors

Microfluxgate sensor with flat coil and double-sided symmetrical core has significantly improved parameters over the original asymmetric single-sided core design. The magnetic circuit of the new sensor is more closed and so the core is deeper saturated. The sensor hysteresis was decreased from 30 μT to 2.5 μT (for full range). Noise level was decreased from 242 nT to 27 nT rms (0.1 mHz to 10 Hz...

Single-borehole imaging using gravity gradiometer data

We present a feasibility study for interpretation of gravity gradient surveys in a single borehole using both an analytic and inverse-based approach. We analytically solve for distance and direction angles to a point source using the components of the gravity gradient tensor from a set of observations in a single borehole. We then generalize this approach to include the response due to a prisma...