초록 ▼

A dynamic range sensor that measures the distance to a target or amount of material in a container. The sensor has a transducer and a controller that is coupled to the transducer. The controller generates a first command signal for the transducer, detects a first echo signal from the transducer, and

A dynamic range sensor that measures the distance to a target or amount of material in a container. The sensor has a transducer and a controller that is coupled to the transducer. The controller generates a first command signal for the transducer, detects a first echo signal from the transducer, and determines whether the first echo signal was received by the transducer within a near-field time. If the first echo signal was received within the near-field time, the controller detects a second echo signal of a predetermined magnitude. If a second echo signal is not detected within a predetermined amount of time, the controller ignores the first echo signal and generates a second command signal different than the first command signal. The controller modifies the second command signal until a second echo signal is detected. The controller converts either the first echo signal or the difference between the first echo signal and the second echo signal to a distance measurement or volumetric representation of the amount of material in the container. Preferably, the transducer is driven at resonance with a series of pulses such that the frequency of the pulses matches the transducer's temperature-dependent frequency characteristics.

대표청구항 ▼

A dynamic range sensor that measures the distance to a target or amount of material in a container. The sensor has a transducer and a controller that is coupled to the transducer. The controller generates a first command signal for the transducer, detects a first echo signal from the transducer, and

A dynamic range sensor that measures the distance to a target or amount of material in a container. The sensor has a transducer and a controller that is coupled to the transducer. The controller generates a first command signal for the transducer, detects a first echo signal from the transducer, and determines whether the first echo signal was received by the transducer within a near-field time. If the first echo signal was received within the near-field time, the controller detects a second echo signal of a predetermined magnitude. If a second echo signal is not detected within a predetermined amount of time, the controller ignores the first echo signal and generates a second command signal different than the first command signal. The controller modifies the second command signal until a second echo signal is detected. The controller converts either the first echo signal or the difference between the first echo signal and the second echo signal to a distance measurement or volumetric representation of the amount of material in the container. Preferably, the transducer is driven at resonance with a series of pulses such that the frequency of the pulses matches the transducer's temperature-dependent frequency characteristics. rt is non-conductive in the vicinity of the at least one antenna disposed with its magnetic dipole moment tilted or perpendicular with respect to the longitudinal axis of the support. 3. The apparatus of claim 1, wherein the first and/or second electrode comprises an array of circumferentially spaced apart azimuthal electrodes. 4. The apparatus of claim 1, wherein the first and/or second electrode comprises an annular electrode. 5. The apparatus of claim 1, wherein the antenna located between the first and second electrode is disposed with its magnetic dipole moment tilted or perpendicular with respect to the longitudinal axis of the support. 6. The apparatus of claim 1, wherein the first electrode is coupled to the second electrode by a conductor. 7. The apparatus of claim 1, wherein the current path passes through the at least one antenna located between the first and second electrodes. 8. A method for altering the flow of an axial electric current along a subsurface borehole in the vicinity of an antenna disposed within the borehole to direct the path of said current near said antenna, the antenna being disposed such that the magnetic dipole moment of the antenna is tilted or perpendicular with respect to the borehole axis and being adapted to transmit and/or receive electromagnetic energy, comprising; a) providing a first electrode within the borehole; b) providing a second electrode within the borehole, the second electrode positioned such that the antenna is located between the first and second electrodes; and c) coupling the first and second electrodes with a conductor to provide a path through the antenna for the axial current to flow between the electrodes. 9. The method of claim 8, wherein the first and second electrodes are coupled by a wire.