Abstract: Systems and methods of determining a boundary area for animals, including a transmitter unit to generate and transmit a plurality of boundary signals, a receiver unit having one or more sensors to detect one or more characteristics of the boundary signals, and a user interface configured to communicate with the receiver unit, the user interface including a boundary program component to sequentially acquire boundary data corresponding to the plurality of boundary signals at a series of boundary perimeter locations, and to transmit the acquired data and instructions to the receiver unit to enable the receiver unit to determine proximity of the receiver unit relative to each perimeter location.

Abstract: Systems and methods of determining a boundary area for animals, including a transmitter unit to generate and transmit a plurality of boundary signals, a receiver unit having one or more sensors to detect one or more characteristics of the boundary signals, and a user interface configured to communicate with the receiver unit, the user interface including a boundary program component to sequentially acquire boundary data corresponding to the plurality of boundary signals at a series of boundary perimeter locations, and to transmit the acquired data and instructions to the receiver unit to enable the receiver unit to determine proximity of the receiver unit relative to each perimeter location.

Abstract: Described is a boundary proximity determining system for wirelessly defining a boundary having a programmable shape and for indicating the occurrence of a rover unit traversing the boundary. The boundary proximity determining system includes a base station unit that generates a plurality of magnetic fields. The boundary proximity determining system also includes a rover unit that is responsive to the generated magnetic fields such that the rover unit defines the boundary in terms of the intensities and polarities of the magnetic fields. The rover unit determines whether the rover unit is within or outside the boundary by determining the current location of the rover unit in terms of the intensities and polarities of the magnetic fields and comparing the current location to the boundary.

Abstract: Described is a boundary proximity determining system for wirelessly defining a boundary having a programmable shape and for indicating the occurrence of a rover unit traversing the boundary. The boundary proximity determining system includes a base station unit that generates a plurality of magnetic fields. The boundary proximity determining system also includes a rover unit that is responsive to the generated magnetic fields such that the rover unit defines the boundary in terms of the intensities and polarities of the magnetic fields. The rover unit determines whether the rover unit is within or outside the boundary by determining the current location of the rover unit in terms of the intensities and polarities of the magnetic fields and comparing the current location to the boundary.

Abstract: A proximity detection system for determining when a single channel receiver becomes proximate to any point on a wireless closed boundary continuously generated by a transmitter. The transmitter includes a magnetic field generator broadcasting a composite, modulated, time-varying magnetic field signal of a particular carrier frequency. The receiver forms a measure of the broadcast magnetic field intensity incident to the location of the receiver or a measure of the power or energy of incident field.

Abstract: A proximity detection system for determining when a single channel receiver becomes proximate to any point on a wireless closed boundary continuously generated by a transmitter. The transmitter includes a magnetic field generator broadcasting a composite, modulated, time-varying magnetic field signal of a particular carrier frequency. The receiver forms a measure of the broadcast magnetic field intensity incident to the location of the receiver or a measure of the power or energy of incident field.

Abstract: A passive, non-multiplexed, two-axis antenna for sensing time-varying magnetic fields of a particular carrier frequency at a second point in space as produced by a electromagnetic field generator located at a first point in space. The antenna has a particular sensitive plane and produces a single output signal having amplitude proportionally related to the magnitude of the incident magnetic field's vector projection onto the antenna's sensitive plane. If the phase of the magnetic field is known, then the antenna's signal is processed to obtain the incident magnetic field's vector components. The antenna enables the realization of two- or three-axis magnetic field receivers with reduced signal processing complexity, cost and power requirements.

Abstract: A passive, non-multiplexed, two-axis antenna for sensing time-varying magnetic fields of a particular carrier frequency at a second point in space as produced by a electromagnetic field generator located at a first point in space. The antenna has a particular sensitive plane and produces a single output signal having amplitude proportionally related to the magnitude of the incident magnetic field's vector projection onto the antenna's sensitive plane. If the phase of the magnetic field is known, then the antenna's signal is processed to obtain the incident magnetic field's vector components. The antenna enables the realization of two- or three-axis magnetic field receivers with reduced signal processing complexity, cost and power requirements.

Abstract: A proximity detection system for determining when a single channel receiver becomes proximate to any point on a wireless closed boundary continuously generated by a transmitter. The transmitter includes a magnetic field generator broadcasting a composite, modulated, time-varying magnetic field signal of a particular carrier frequency. The receiver forms a measure of the broadcast magnetic field intensity incident to the location of the receiver or a measure of the power or energy of incident field.

Abstract: A logarithmic current measurement circuit for operating upon an input electric signal utilizes a quad, dielectrically isolated, well-matched, monolithic bipolar transistor array. One group of circuit components within the circuit cooperate with two transistors of the array to convert the input signal logarithmically to provide a first output signal which is temperature-dependant, and another group of circuit components cooperate with the other two transistors of the array to provide a second output signal which is temperature-dependant. A divider ratios the first and second output signals to provide a resultant output signal which is independent of temperature. The method of the invention includes the operating steps performed by the measurement circuit.