Provided is a technique for specifying a medium more simply. A medium sensor device includes an antenna, a storage unit that stores a medium identification table in which a medium corresponding to an antenna impedance has been determined beforehand, and a medium specification unit that specifies the impedance of the antenna and specifies a medium in the vicinity of the antenna by referring to the medium identification table.

A method for ground penetrating radar analysis of a scenario, having a surface, with respect to a cartesian reference system S(x, y) having origin O(0, 0) and axes x and y. The method comprises a step of prearranging a gpr apparatus that comprises at least one gpr sensor, a control unit, a centre of reference C(x.sub.c, y.sub.c) having coordinates x.sub.c and y.sub.c with respect to the cartesian reference system S(x, y), at least one image acquisition devices, each image acquisition devices (110,120) having a pointing direction γ.sub.j known with respect to the centre of reference C(x.sub.c, y.sub.c). The method comprises then the steps of handling the gpr apparatus on the surface and detecting possible underground objects by means of gpr technique.

A generation system and method for a high-precision three-dimensional navigation map of a fully mechanized mining surface, applicable to use in the technical field of unmanned mining. The generation system comprises a channel wave seismometer, a laser radar, a combined navigation device, a ground penetrating radar, and a data processing unit; the data processing unit acquires data collected by sensors; perform coordinate conversion, feature fusion and consistency processing on the collected data to generate a Delaunay triangle network of a coal seam, a fault/fold, and a roadway; draw a high-precision profile map of the triangle map, calculate a topological relation of the profile map, generate a topological data structure of the profile map, establish a navigation information automatic query database platform based on the high-precision profile map, and construct the high-precision three-dimensional navigation map of the fully mechanized mining surface. The high-precision three-dimensional navigation map generated by the present invention can provide accurate thickness information of the coal seam, a varied dip angle of the coal seam and a position of a dangerous geological structure space to fully mechanized mining equipment, and has functions such as high-precision positioning, information sensing, and path planning.

A metal detector 20 includes a detection signal acquisition unit 31, a threshold value setting and updating unit 32, and a determination unit 33. The detection signal acquisition unit 31 acquires a detection signal that changes according to the detection strength for a rebar W1 contained in concrete W, on the surface of the concrete W. The threshold value setting and updating unit 32 sets a threshold value in order to determine the presence or absence of the rebar W1 on the basis of the maximum value and/or the minimum value included in the acquisition results for the detection signal acquired by the detection signal acquisition unit 31. The determination unit 33 determines the presence or absence of the rebar W1 by using the threshold value set in the threshold value setting and updating unit 32.

Systems and methods for ground penetrating radar for determining thickness, density and moisture are therefore provided. According to an embodiment, a ground penetrating radar (GPR) system comprises a system controller configured to produce an electromagnetic signal for signal penetration of a pavement material. Further, the GPR system comprises a frequency modulated continuous wave controller. Further, the GPR system comprises an ultra wide band (UWB) antenna coupled to the system controller, wherein the UWB antenna is configured to transmit the produced electromagnetic signal to the pavement material and receive the electromagnetic signal as a reflection from the pavement material. Further, the system controller is further configured to receive the electromagnetic signal from the UWB antenna.

A method and a device for probing a subsurface structure. The method includes sending an electromagnetic wave into the structure, receiving an echo of the electromagnetic wave from the structure and processing the echo for deriving an internal feature of the structure. The sending the electromagnetic wave into the structure includes subsequently sending a plurality of electromagnetic probe signals with differing frequency spectra into the structure. Each probe signal includes at least two non-zero spectral components. The receiving the echo includes receiving an echo signal for each probe signal. The processing the echo includes determining at least one amplitude and phase for each echo signal.

A method for detecting at least one target buried in an area of the ground, using a ground-penetrating radar, the method includes the steps of: acquiring a measurement of a signal transmitted by each transmitting antenna and reflected in the area of the ground, converting an estimate, into the frequency domain, of the propagation channel for each pair consisting of a transmitting antenna and of a receiving antenna, defining a first hypothesis H0 corresponding to an absence of target in the area of the ground, defining a second hypothesis H1 corresponding to the presence of at least one target in the area of the ground, performing a test of the likelihood ratio between the likelihood of the channel matrix under the second hypothesis H1 and the likelihood of the channel matrix under the first hypothesis H0, in order to conclude whether a target is present at a given position in the area of the ground.

A method for detecting a horizontally buried linear object is provided, the horizontally buried linear object having a longitudinal extension. The method comprises moving, with a flying platform comprising a radar for synthetic aperture radar, SAR, vertical imaging, along a trajectory corresponding to a synthetic aperture. The method further comprises transmitting and receiving radar signals while moving along the trajectory corresponding to the synthetic aperture. The method also comprises forming a SAR image based on collected data representing radar signal reflections received from the ground. The method additionally comprises detecting one or more features in the formed SAR image relating to the horizontally buried linear object. Said trajectory is oriented in a direction substantially perpendicular to an expected orientation of the longitudinal extension of the horizontally buried object and traversing the horizontally buried object.

A method for calculating a magnetic influence factor (MIF) between an atom and a resonant atom of a molecule of a material includes determining a current magnetic field strength at a test location above a quantity of material buried at the test location, transmitting a test signal from an antenna at the test location, the test signal comprising a test fundamental frequency, and detecting, at the test location, a reflected wave comprising the test fundamental frequency on the antenna. The method includes varying the test fundamental frequency while retransmitting the test signal and detecting a reflected wave until reflected waves of various test frequencies are detected and identifying from the detected reflected waves a resonant frequency corresponding to a maximum magnitude of the detected reflected waves. The material includes molecules with a resonant atom and at least one atom different than the resonant atom.

A device implementing antennas transmitting and receiving electromagnetic waves for measuring the bulk dielectric properties of a material under test having over a pre-defined surface area. The sample of the material under test might be cylindrical in shape. The device includes a spacer of known dielectric properties and geometries, placed between the material under test and the transmitting and receiving antennas, as well as at least one plate of a material having known electromagnetic properties placed below the material under test.