Abstract: A system for identifying the location of a dipole magnetic field source below ground. The system comprises a first receiver assembly and a second receiver assembly each configured to detect the dipole magnetic field in three dimensions from a transmitter and generate antenna signals indicative of the detected dipole magnetic field. The first receiver assembly detects the dipole magnetic field from the transmitter substantially simultaneously as the second receiver assembly simultaneously detects the dipole magnetic field from the transmitter. The second receiver assembly is movable relative to both the first receiver assembly and the transmitter. A processor determines the location of the transmitter below ground based on the antenna signals generated by the first and second receiver assemblies.

Abstract: A collapsible portable shelter unit when in the collapsed mode is light and compact to make transport and storage convenient, but when opened provides an enclosed space that can be used for various purposes, which has an integrated high strength structured frame by the action of the interlocking extrusions which also provide resistance to water and wind infiltration. As needed, exterior windows and doors, air conditioning, electrical supply and other customization as required by the users' needs.

Abstract: A receiver system for identifying a location of a magnetic field source using at least two tri-axial antennas. The two tri-axial antennas are laterally displaced from one another and may also be held in a substantially horizontal plane. Each of the tri-axial antennas detects a dipole magnetic field from the magnetic field source in three dimension. The receiver system uses a processor to receive an antenna signal from each of the two tri-axial antennas to determine the location of the magnetic field source using the antenna signals.

Abstract: A method for noise signal analysis and communication with an underground transmitter. The method comprises the steps of measuring a noise floor when no signal is transmitted from a transmitter, detecting a signal when the transmitter is transmitting, and estimating the noise free component of the signal by removing the noise floor measurement. The measurement of the noise floor and detecting the signal from the transmitter may be done using a root mean square technique. The noise floor measurement can be removed from the measured signal by subtracting the noise floor measurement from the measured signal or alternatively by calculating the square root of the difference between the square of the measured signal and the square of the noise floor measurement. The noise estimation technique may be used in connection with a differential phased shift keying communication scheme or other modulation techniques.

Abstract: A method and receiver system for identifying a location of a magnetic field source using two horizontally displaced tri-axial antennas. In a preferred embodiment two tri-axial antennas are positioned at opposite ends of a receiver frame. Each antenna detects in three dimensions a magnetic field from a source or transmitter. The receiver is maintained in a horizontal plane and the receiver is moved in the horizontal plane until a flux angle measured at each of the two points is zero so that the receiver is in the vertical plane perpendicular to the axis of the source. The depth and location of the source in three dimensions relative to the receiver is determined using the detected field values. The receiver is moved in a direction defined by a line containing the two points of the receiver until a magnitude of the magnetic field detected at each of the two points is substantially the same so that the receiver is positioned above the source.

Abstract: A method and receiver system for identifying a location of a magnetic field source using two horizontally displaced tri-axial antennas. In a preferred embodiment two tri-axial antennas are positioned at opposite ends of a receiver frame. Each antenna detects in three dimensions a magnetic field from a source or transmitter. The receiver is maintained in a horizontal plane and the receiver is moved in the horizontal plane until a flux angle measured at each of the two points is zero so that the receiver is in the vertical plane perpendicular to the axis of the source. The depth and location of the source in three dimensions relative to the receiver is determined using the detected field values. The receiver is moved in a direction defined by a line containing the two points of the receiver until a magnitude of the magnetic field detected at each of the two points is substantially the same so that the receiver is positioned above the source.

Abstract: A method for guiding a downhole tool assembly using a receiver system. The receiver system comprises two antenna assemblies disposed in a substantially horizontal plane. The antenna assemblies are set at a target point such that the two antenna assemblies each lie on a desired borepath. The two antenna assemblies simultaneously detect in three dimensions a magnetic field source transmitted from the downhole tool assembly to determine a position of the downhole tool assembly.

Abstract: A collapsible portable shelter unit when in the collapsed mode is light and compact to make transport and storage convenient, but when opened provides an enclosed space that can be used for various purposes, which has an integrated high strength structured frame by the action of the interlocking extrusions which also provide resistance to water and wind infiltration. As needed, exterior windows and doors, air conditioning, electrical supply and other customization as required by the users' needs.

Abstract: A method for noise signal analysis and communication with an underground transmitter. The method comprises the steps of measuring a noise floor when no signal is transmitted from a transmitter, detecting a signal when the transmitter is transmitting, and estimating the noise free component of the signal by removing the noise floor measurement. The measurement of the noise floor and detecting the signal from the transmitter may be done using a root mean square technique. The noise floor measurement can be removed from the measured signal by subtracting the noise floor measurement from the measured signal or alternatively by calculating the square root of the difference between the square of the measured signal and the square of the noise floor measurement. The noise estimation technique may be used in connection with a differential phased shift keying communication scheme or other modulation techniques.

Abstract: A method and receiver system for identifying a location of a magnetic field source using two horizontally displaced tri-axial antennas. In a preferred embodiment two tri-axial antennas are positioned at opposite ends of a receiver frame. Each antenna detects in three dimensions a magnetic field from a source or transmitter. The receiver is maintained in a horizontal plane and the receiver is moved in the horizontal plane until a flux angle measured at each of the two points is zero so that the receiver is in the vertical plane perpendicular to the axis of the source. The depth and location of the source in three dimensions relative to the receiver is determined using the detected field values. The receiver is moved in a direction defined by a line containing the two points of the receiver until a magnitude of the magnetic field detected at each of the two points is substantially the same so that the receiver is positioned above the source.

Abstract: A method for noise signal analysis and communication with an underground transmitter. The method comprises the steps of measuring a noise floor when no signal is transmitted from a transmitter, detecting a signal when the transmitter is transmitting, and estimating the noise free component of the signal by removing the noise floor measurement. The measurement of the noise floor and detecting the signal from the transmitter may be done using a root mean square technique. The noise floor measurement can be removed from the measured signal by subtracting the noise floor measurement from the measured signal or alternatively by calculating the square root of the difference between the square of the measured signal and the square of the noise floor measurement. The noise estimation technique may be used in connection with, a differential phased shift keying communication scheme or other modulation techniques.

Abstract: A method and receiver system for identifying a location of a magnetic field source using two horizontally displaced tri-axial antennas. In a preferred embodiment two tri-axial antennas are positioned at opposite ends of a receiver frame. Each antenna detects in three dimensions a magnetic field from a source or transmitter. The receiver is maintained in a horizontal plane and the receiver is moved in the horizontal plane until a flux angle measured at each of the two points is zero so that the receiver is in the vertical plane perpendicular to the axis of the source. The depth and location of the source in three dimensions relative to the receiver is determined using the detected field values. The receiver is moved in a direction defined by a line containing the two points of the receiver until a magnitude of the magnetic field detected at each of the two points is substantially the same so that the receiver is positioned above the source.

Abstract: A method for noise signal analysis and communication with an underground transmitter. The method comprises the steps of measuring a noise floor when no signal is transmitted from a transmitter, detecting a signal when the transmitter is transmitting, and estimating the noise free component of the signal by removing the noise floor measurement. The measurement of the noise floor and detecting the signal from the transmitter may be done using a root mean square technique. The noise floor measurement can be removed from the measured signal by subtracting the noise floor measurement from the measured signal or alternatively by calculating the square root of the difference between the square of the measured signal and the square of the noise floor measurement. The noise estimation technique may be used in connection with, a differential phased shift keying communication scheme or other modulation techniques.

Abstract: A method and receiver system for identifying a location of a magnetic field source using two horizontally displaced tri-axial antennas. In a preferred embodiment two tri-axial antennas are positioned at opposite ends of a receiver frame. Each antenna detects in three dimensions a magnetic field from a source or transmitter. The receiver is maintained in a horizontal plane and the receiver is moved in the horizontal plane until a flux angle measured at each of the two points is zero so that the receiver is in the vertical plane perpendicular to the axis of the source. The depth and location of the source in three dimensions relative to the receiver is determined using the detected field values. The receiver is moved in a direction defined by a line containing the two points of the receiver until a magnitude of the magnetic field detected at each of the two points is substantially the same so that the receiver is positioned above the source.

Abstract: The present invention provides a method of analysing an object (29) (for example a wive or a steut), comprising the steps of: (a) irradiating the object with a Terahertz pulse of electromagnetic radiation, such that a portion of the irradiating radiation couples to the object as a surface wave; (b) detecting radiation reflected and/or scattered from the object to obtain a time domain waveform; (c) extracting the parts of the radiation detected in step (b) relating to the surface wave on the object and (d) analysing the radiation identified in step (c) in order to derive information relating to a physical characteristic (for example the thickness of a coating) of the object.

Abstract: Method and apparatus for investigating a sample particularly a pharmaceutical tablet. An emitter and/or the sample are initially positioned so that the emitter is at a predetermined distance and normal angle to a first point on a surface of the sample. The emitter then irradiates the sample with radiation having a plurality of frequencies in the range from 25 GHz to 100 THz at a plurality of points on the surface of the sample. Relative motion is possible between the emitter and the sample so that the surface of the sample can be tracked to maintain the predetermined distance and normal angle at each of the plurality of points, and allow radiation transmitted and/or reflected from the sample at the plurality of points to be detected. This has particular application to imaging the structure or composition of a coating on a pharmaceutical tablet.

Abstract: Novel liquid cleansing products are disclosed. The cleansing products are comprised of a first colored structured liquid and a second colored structured liquid that when dispensed from a suitable dispenser, mix together to form a new colored cleansing product prior to, and during, use.

Abstract: A probe array (1) for an imaging system for examining an object (19) comprising at least one emitter (7) for emitting radiation, a plurality of detectors (9) for detecting radiation and means for directing radiation emitted by the at least one emitter (7) to the object (19) and for directing radiation reflected from the object (19) to at least two of the plurality of detectors (9) wherein in use the emitted radiation is scanned by means (21) across the object (19)

Abstract: Method and apparatus for irradiating a sample with Terhertz radiation and detecting non-specular radiation in order to characterise the internal structure of the sample. Terahertz radiation specularly reflected from the surface is minimised so that it does not mask the weaker signal originating from the internal structure of the sample.