Abstract: Method, apparatus and system for determining accurately at least one coordinate of a sensor (or a transducer including a sensor) relative to a predetermined reference location, particularly where the sensor is part of a transducer for ground penetrating radar. A marker detector is positioned in a predetermined relationship with the sensor; a marker is detected with the marker detector and positional information associated with the marker is received, from which a position of the transducer or sensor is determined, based on the received positional information associated with the marker and the predetermined relationship between the marker detector and the sensor. The marker may, for example, be a bar code and the marker detector may be an optical scanner. The sensor may be a receiving antenna for a GPR signal.

Abstract: Ground penetrating radar (GPR) is a technique that may be used to image the inside of a structure by collecting the echoes (or reflections) resulting from electromagnetic signals such as, for example, electromagnetic waves of typically high frequency, being radiated into the structure. Typically, the rebars inside a reinforced concrete structure are strong radar wave reflectors. Locating rebars within a reinforced concrete structure and determining their depths may be accomplished by analyzing the reflections, particularly the amplitudes and arrival times of the reflections, from the rebars in the reinforced concrete structure. Provided is a method and system for determining, for a substantially concrete structure having at least a first side and containing one or more reinforcing bars, a distance of the one or more reinforcing bars from the first side of the substantially concrete structure.

Abstract: An antenna system for ground-penetrating radar use, comprising first and second co-located antenna element pairs orthogonally oriented with respect to each other. Each of the element pairs includes a transmit element and a receive element. A metallic enclosure (such as a box) shields the element pairs and is open on one side to face a structure to be probed by signals from the transmit elements. The transmit and receive elements are dimensioned, shaped and arranged (a) to achieve low mutual impedance between the elements, (b) to have high sensitivity to reflected signals received from the structure being probed; and (c) to accommodate a desired rise time of a transmit pulse. The transmit elements and receive elements preferably are electrical dipoles but they may also be magnetic dipoles such as slot antennas. When electrical dipoles are employed, they may be formed of elongated diamond-shaped conductive surfaces or be of other appropriate geometries.

Abstract: Ground penetrating radar (GPR) is a technique that may be used to image the inside of a structure by collecting the echoes (or reflections) resulting from electromagnetic signals such as, for example, electromagnetic waves of typically high frequency, being radiated into the structure. Typically, the rebars inside of a reinforced concrete structure are strong radar wave reflectors. Locating deteriorated areas within a reinforced concrete structure may be accomplished by analyzing the reflections, particularly the amplitudes of the reflections, from the rebars in the reinforced concrete structure. Furthermore, the extent of deterioration of these located areas may be determined from such analysis. Significantly, the system and method described herein, when applied to determine the extent of deterioration of one or more areas of a reinforced concrete bridge deck, is effective even if a layer of asphalt is laminated to the surface of the reinforced bridge deck.