Abstract: A multi-sensor electromagnetic (EM) system and method for measuring gradients of EM signals. The multi-sensor EM system includes a frame; a transmitter device attached to the frame and configured to generate a primary EM field; a receiver device attached to the frame and configured to record a secondary EM field generated by the earth after being excited by the primary EM field; and a gradient sensor device attached to the frame and configured to record a gradient of the secondary EM field.

Abstract: A multi-sensor electromagnetic (EM) system and method for measuring gradients of EM signals. The multi-sensor EM system includes a frame; a transmitter device attached to the frame and configured to generate a primary EM field; a receiver device attached to the frame and configured to record a secondary EM field generated by the earth after being excited by the primary EM field; and a gradient sensor device attached to the frame and configured to record a gradient of the secondary EM field.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a survey EM transmitter for generating survey EM signals within a first frequency range; a calibration EM transmitter for generating a calibration signal; a receiver section, including a receiver housing and a receiver, that measures both the survey EM signals and the calibration signal; and a calibration device connected to the calibration EM transmitter and to the receiver, the calibration device configured to control a frequency and waveform of the calibration signal. The calibration device is further configured to calculate a response function of the receiver, based on the calibration signal.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a platform; a coil for measuring EM signals; and first to third suspension mechanisms located between the platform and the coil so that the coil oscillates relative to the platform, and the first to third suspension mechanisms attenuate motion induced noise introduced by towing the receiver system above ground.

Abstract: An electromagnetic geophysical exploration system includes a first transmitter-receiver pair that includes a first transmitter configured to transmit a first waveform in a first spectrum and a first receiver configured to sense signals in the first spectrum; and a second transmitter-receiver pair that includes a second transmitter configured to transmit a second waveform in a second spectrum, the second spectrum having a frequency higher than a frequency of the first spectrum, and a second receiver configured to sense signals in the second spectrum; and a control portion. The control portion controls the first transmitter to transmit the first waveform with a first given strength or shape in the first spectrum, and controls the second transmitter to transmit the second waveform with a second given strength or shape in the second spectrum, after a specified time delay.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a platform; a coil for measuring EM signals; and first to third suspension mechanisms located between the platform and the coil so that the coil oscillates relative to the platform, and the first to third suspension mechanisms attenuate motion induced noise introduced by towing the receiver system above ground.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a survey EM transmitter for generating survey EM signals within a first frequency range; a tracking EM transmitter for generating tracking signals within a second frequency range; and a receiver section including a receiver that measures both the survey EM signals and the tracking signals.

Abstract: A method and system for active cancellation of transient signals and dynamic loop configuration for geophysical exploration is disclosed. The method includes controlling a transmitter to transmit a waveform in a frequency spectrum during an on-time. The transmitter includes a plurality of turns of wire. The method also includes controlling a plurality of switches to direct an electrical signal through the plurality of turns of wire. The plurality of switches electrically coupled to the plurality of turns of wire. The method further includes controlling a switch of the plurality of switches to direct a first portion of a transient current in an opposite direction from a direction of a second portion of the transient current during an off-time.

Abstract: A multi-sensor electromagnetic (EM) system and method for measuring gradients of EM signals. The multi-sensor EM system includes a frame; a transmitter device attached to the frame and configured to generate a primary EM field; a receiver device attached to the frame and configured to record a secondary EM field generated by the earth after being excited by the primary EM field; and a gradient sensor device attached to the frame and configured to record a gradient of the secondary EM field.

Abstract: A computing device and method for removing noise associated with an excitation signal and its odd harmonics. A computing system for processing electromagnetic (EM) signals includes an interface that receives raw data indicative of a time rate of change of a magnetic field as recorded with a receiver coil while airborne, wherein the magnetic field includes a primary source excitation; and a processor connected to the interface. The processor is configured to calculate a rotation of the receiver coil relative to a desired orientation; derotate the raw EM data based on the rotation of the receiver coil relative to the desired orientation and on the primary source excitation, to obtain derotated EM data; and generate an image of a surveyed subsurface based on the derotated EM data.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a frame; a first EM receiver attached to the frame and configured to measure the EM signals within a first frequency range; and a second EM receiver attached to the frame and configured to measure the EM signals within a second frequency range. Corresponding axes of the first and second EM receivers are substantially parallel to each other.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a platform; a coil for measuring EM signals; and first to third suspension mechanisms located between the platform and the coil so that the coil oscillates relative to the platform, and the first to third suspension mechanisms attenuate motion induced noise introduced by towing the receiver system above ground.

Abstract: Systems and methods for a composite magnetic field sensor is disclosed. The electromagnetic survey system includes a first receiver configured to sense signals in a first spectrum based on sensing a magnetic field. The system includes a second receiver configured to sense signals in a second spectrum based on sensing a time rate of change of the magnetic field. The second spectrum has a frequency range higher than the first spectrum. The system further includes a transmitter configured to transmit a specified waveform and a control system configured to control the transmitter to transmit the specified waveform. The control system is also configured to receive signals sensed by the first receiver, receive signals sensed by the second receiver, and store the signals received from the first receiver and the signals received from the second receiver.

Abstract: A system and method for electromagnetic geophysical exploration is provided. The system includes a first transmitter (210) configured to transmit a first waveform in a first spectrum and a first receiver (212) configured to sense signals in the first spectrum. The system also includes a second transmitter (220) configured to transmit a second waveform in a second spectrum, and a second receiver (222) configured to sense signals in the second spectrum and minimum-coupled to the second transmitter. The second spectrum has a frequency higher than a frequency of the first spectrum. The system further includes a control portion configured to control the first transmitter to transmit the first waveform, and control the second transmitter to transmit the second waveform after a specified time delay. The control portion is configured to receive signals sensed by the first receiver in the first spectrum, and receive signals sensed by the second receiver in the second spectrum.

Abstract: A composite electromagnetic (EM) system and method for measuring naturally occurring magnetic fields and controlled magnetic fields. The composite EM system includes a housing, an audio-magnetotelluric (AMT) system attached to the housing and measuring natural magnetic fields generated by earth, a frequency-domain EM (FDEM) system attached to the housing and measuring controlled magnetic fields generated by a controlled source, and a position and orientation (POS) system attached to the housing and configured to calculate an orientation and a position of the AMT system and housing relative to the earth. The housing is configured to be attached to an aircraft for being airborne while measuring the natural magnetic fields and the controlled magnetic fields.

Abstract: A multi-sensor electromagnetic (EM) system and method for measuring gradients of EM signals. The multi-sensor EM system includes a frame; a transmitter device attached to the frame and configured to generate a primary EM field; a receiver device attached to the frame and configured to record a secondary EM field generated by the earth after being excited by the primary EM field; and a gradient sensor device attached to the frame and configured to record a gradient of the secondary EM field.

Abstract: There are systems and methods for performing a geophysical survey using a hybrid aircraft which includes an apparatus configured to perform the geophysical survey. The system including: three mutually orthogonal transmitters configured to transmit electromagnetic (EM) waveforms towards the ground which creates a secondary magnetic field, wherein the three mutually orthogonal transmitters are attached to the hybrid aircraft; three mutually orthogonal null-coupled receivers configured to obtain measurements associated with the secondary magnetic field, wherein the three mutually orthogonal null-coupled receivers are attached to the hybrid aircraft; and three mutually orthogonal gradient receivers configured to obtain measurements, wherein the three mutually orthogonal gradient receivers are attached to the hybrid aircraft.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a survey EM transmitter for generating survey EM signals within a first frequency range; a tracking EM transmitter for generating tracking signals within a second frequency range; and a receiver section including a receiver that measures both the survey EM signals and the tracking signals.

Abstract: An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a frame; a first EM receiver attached to the frame and configured to measure the EM signals within a first frequency range; and a second EM receiver attached to the frame and configured to measure the EM signals within a second frequency range. Corresponding axes of the first and second EM receivers are substantially parallel to each other.

Abstract: An offer amalgamating system receives offers for an item or service advertised for sale in differing quantities at differing prices and aggregates a display of the offers to provide to all offerers an indication as to when a price/quantity sale point is being approached. In this way an offerer may form part of an aggregated offer and receive the item or service at a lower cost than otherwise.