2933results about "Detection using electromagnetic waves" patented technology

Apparatus and methods are disclosed for detecting anomalies in microwave penetrable material that may be used for locating plastic mines or pipes underneath the ground. A transmitter is positioned at a plurality of different positions above the ground. A microwave signal is transmitted that is stepped over a plurality of frequencies. At each position, a plurality of reflections are received corresponding to each of the plurality of frequencies that were transmitted. A complex target vector may be produced at each position that contains complex values corresponding to magnitude, phase, and time delay for each of the plurality of reflections received at that location. A complex reference data vector may be produced, either based on predetermined values or based on data from the received plurality of reflections. A comparison is made between the complex target vector and the complex reference data vector to produce a channel vector. In one embodiment, an operator may be applied to the channel vector such as a complex filter matrix or to add a complex conjugate. A response signal is produced and anomalies are detected by variations in the response signal with respect to the plurality of positions.

An object detection system includes a radar detection means (2), an image detection means (3), and a collating means (4). The collating means (4) performs a collation between an object detected by the radar detection means (2) in a present collation and an object that has been determined as being detected by the radar detection means (2) and the image detection means (3) in a previous collation (S 10, S 11), further performs a collation between an object detected by the image detection means (3) in a present collation and an object that has been determined as being detected by the radar detection means (2) and the image detection means (3) in the previous collation (S 12, S 13) when it is determined that the identical object is detected by the radar detection means (2) and the image detection means (3) in the previous collation. Then the collating means (4) determines whether the radar detection means (2) and the image detection means (3) detect the identical object based on the collations (S 14).

A combined resistivity tool incorporating both induction / propagation antennas and lateral resistivity antennas disposed in recesses of downhole tubulars, in which a lateral resistivity antenna includes an insulating base layer disposed in the recess; a toroidal antenna disposed over the insulating base layer; and a shield disposed over the recess.