A magnetometer sensor that detects tampering is described. The sensor samples magnetometer data and computes a set of vectors based on the magnetometer data. The sensor detects a tampering of the magnetic sensor based on determining that the set of vectors is outside the reference plane for the magnetometer sensor. The sensor generates a notification to a security system coupled to the magnetometer sensor. The notification indicating the tampering of the magnetometer sensor.

A magnetometer sensor that detects tampering is described. The sensor samples magnetometer data and computes a set of vectors based on the magnetometer data. The sensor detects a tampering of the magnetic sensor based on determining that the set of vectors is outside the reference plane for the magnetometer sensor. The sensor generates a notification to a security system coupled to the magnetometer sensor. The notification indicating the tampering of the magnetometer sensor.

In an embodiment, a method for providing power to a load using a wireless power receiver includes: wirelessly receiving power using an LC tank; rectifying a voltage of the LC tank using a rectifier; setting a switched-mode power supply coupled between the rectifier and the load in bypass mode; after setting the switched-mode power supply in bypass mode, providing power to the load without switching transistors of the switched-mode power supply; and when wireless power reception is interrupted, providing power to the load by switching one or more transistors of the switched-mode power supply.

In an embodiment, a method for providing power to a load using a wireless power receiver includes: wirelessly receiving power using an LC tank; rectifying a voltage of the LC tank using a rectifier; setting a switched-mode power supply coupled between the rectifier and the load in bypass mode; after setting the switched-mode power supply in bypass mode, providing power to the load without switching transistors of the switched-mode power supply; and when wireless power reception is interrupted, providing power to the load by switching one or more transistors of the switched-mode power supply.

Systems and methods for providing a visualization capability to map magnetic fields. The system utilizes a high-sensitivity magnetic field sensor (e.g., a magnetometer inside a tube made of magnetic shielding material) disposed on one side of a magnetic field modulation screen to acquire measurement data representing an image of a magnetic field. The magnetic field modulation screen includes a multiplicity of magnetic field-generating pixel elements (e.g., current-carrying loops made of electrically conductive material). Optionally, the system also uses compressive sensing techniques to reduce the amount of measurement data required to reconstruct an image of the original magnetic field. Compressive sensing is enabled by not supplying current to a different selected individual magnetic field-generating pixel element of the magnetic field modulation screen at successive sampling times.

Systems and methods for providing a visualization capability to map magnetic fields. The system utilizes a high-sensitivity magnetic field sensor (e.g., a magnetometer inside a tube made of magnetic shielding material) disposed on one side of a magnetic field modulation screen to acquire measurement data representing an image of a magnetic field. The magnetic field modulation screen includes a multiplicity of magnetic field-generating pixel elements (e.g., current-carrying loops made of electrically conductive material). Optionally, the system also uses compressive sensing techniques to reduce the amount of measurement data required to reconstruct an image of the original magnetic field. Compressive sensing is enabled by not supplying current to a different selected individual magnetic field-generating pixel element of the magnetic field modulation screen at successive sampling times.

There is provided a method and system for identifying the location of an obstruction in a pipeline comprising: sensing the magnetic field generated by a pipeline at an initial pressure from a first location along the length of the pipeline to obtain a baseline reading; altering the pressure from a first end until a maximum pressure or minimum pressure is attained; sensing the magnetic field at the maximum or minimum pressure from the first location to obtain a stress reading; and identifying the location of the obstruction as a) being between a second end and the first location when there is a deviation between the stress reading and the baseline reading at the first location or as b) being between the first end and the first location when there is an absence of a deviation between the stress reading and the baseline reading at the first location.

In a general aspect, vapor cells are disclosed that include a dielectric body having a first surface and a second surface. The dielectric body includes a plurality of cavities extending from the first surface to the second surface and ordered periodically to define a photonic crystal structure in the dielectric body. Each cavity has a first opening defined by the first surface and a second opening defined by the second surface. The photonic crystal structure has a photonic band gap. The vapor cells additionally include a first optical window covering the first openings and having a surface bonded to the first surface of the dielectric body to form a seal around each of the first openings. A second optical window covers the second openings and has a surface bonded to the second surface of the dielectric body to form a seal around each of the second openings.

An apparatus for validating magnets on site, including a standard reference magnet for providing a governing reference, a reference magnet for providing a reference based on the governing reference, a gauss meter, a hall probe, and a scanner. The reference magnet is arranged to be taken on site for further magnetic validation and includes guide members to target a nominated magnetic field density.

An apparatus for validating magnets on site, including a standard reference magnet for providing a governing reference, a reference magnet for providing a reference based on the governing reference, a gauss meter, a hall probe, and a scanner. The reference magnet is arranged to be taken on site for further magnetic validation and includes guide members to target a nominated magnetic field density.