Abstract: Apparatus for use in a geophysical prospecting method from a vehicle for site plan pictorial representation of inclusions present in substratum soil which reflect modulated electromagnetic oscillations. This apparatus is particularly useful for detecting inclusions such as veins of water, ore beds, pipelines, unexploded bombs, cavities, ammunition and residual fissures. A transmitter and receiver are mounted in the vehicle with a common quartz oscillator in a sawtooth generator. A transmitting antenna and receiving antenna are provided with an amplifier connected to the latter. A pulse shaper employs the width of received triangular pulses from the amplifier to give needle pulses and a color transmitter has four power amplifiers and is a goniometrically scanned four-cycle transmitter, and accordingly the cathode ray tube has four crosswise arranged horizontal sweep coils in addition to the frame coil.

Abstract: The invention provides a method and a corresponding instrument for measuring the direction of a remote source of radiation, the instrument comprising a support, a detector head rotatably mounted thereon for rotation about a fixed axis, and a position-indicator means which provides an output signal indicating the rotational position of the detector head, the detector head being provided with a detector sensitive to radiation emitted by the remote source and with optics for forming an image of the source which transits across the detector as the detector head rotates, the image-forming optics being such that the image comprises two line-image components which extend transversely to the transit direction and which are oppositely inclined to that direction, and the detector being arranged, in response to the transit across it of each line-image component, to cause the instantaneous angular position of the detector head as indicated by the position indicator to be recorded, there being further provided computer wh

Abstract: A device for determining the position of a vehicle comprises a GPS (Global Positioning System) receiver (6) which supplies vehicle position data at regular intervals on the basis of data received from satellites, a device (1) for dead-reckoning on the basis of the position data from the GPS receiver (6), a compass (2) and at least one wheel sensor (3), and a correction unit (4) which corrects the dead-reckoning values supplied at regular intervals by the dead-reckoning device (1) in dependence on comparison with road position coordinates read from a mass memory (5), notably with characteristic road position coordinates, and outputs the corrected values as vehicle position coordinates.

Abstract: A cable leakage detection system to be placed in a moving vehicle for monitoring signal leakages in a cable television plant whereby an RF detection meter is combined with a global positioning system and a computer control unit to measure radio frequency signal strength, while maintaining the corrected distance between the vehicle and the source of the leak, determine longitude and latitude of the measured signal strength, and store the signal strength, longitude and latitude in data files.

Abstract: Apparatus is disclosed for detecting partially submerged wires and determng the location of the above water portion thereof by injecting into the submerged portion a radio frequency electrical signal, and utilizing radio direction finders to obtain a fix on the resulting radiating above water portion. An insulation cutting probe is used, and a radio frequency injection signal generator is described that minimizes power loss to the water medium.

Abstract: An object detection method and apparatus in which, in order to distinguish only an echo wave which is returned back from an object of interest, such as an underground buried object, from those echo waves returned back from another object of objects, the observation signal is divided (an electromagnetic wave as an echo wave) into portions, and the signal portion is converted into a corresponding frequency region to evaluate that spectral distribution and computes frequency parameter values from the spectrum distribution. The object of interest is detected by comparing the reference data of various fields with the parameters of the object of interest, extracting only an echo wave returned back from the object of interest and displaying a corresponding image.

Abstract: The homing technique for directing an in-ground boring device through the ground from its particular location to a specific target point is disclosed herein. In accordance with this technique, an electromagnetic dipole field containing a predetermined homing signal is generated at the boring device and detected by a specifically configured receiving antenna arrangement at the target point or, in a preferred embodiment where the target point is below ground, at a ground level point directly above or beyond the target point. Means are provided in response to detection of the homing signal for producing an internal electrical signal containing certain information relating to the actual path taken by the boring device as compared to the path or course leading to the target point. The information from this latter signal is then transmitted by means of electromagnetic waves to a remote location where it is used to steer the boring device on a course toward the target.

Abstract: A method and apparatus for producing data indicative of the presence of buried objects, wherein two waveforms I(t) Q(t) are combined with two reference waveforms Ir(t) Qr(t) using filters 10, 12, 14, 16 of two types A, B. Type A has time response Ir(-t) and type B has time response Qr(-t). The products {I(t)@Ir(t)}.multidot.{Q(t)@Qr(t)} and {I(t)@Qr(t)}.multidot.{Q(t)@Ir(t)} from multipliers 18, 20 are subtracted to give V1 and added to give V2 in the combiner 30. A list of object distances (36) is derived from V1. A list of object orientations (46) is derived from V2. Object times (34) are used to section V2 at (40) on a time basis. A correlation operation is represented by @. The invention is particularly applicable to location of buried pipes using ground probing radar, but is also useful in locating planar objects and in other systems. The waveform combination suppresses noise and clutter. I(t) and Ir(t) are quadrature versions of Q(t) and Qr(t). The emitted radiation is circularly polarized.

Abstract: A technique for locating the position of a boring device within the ground with respect to a particular reference location along an above ground path directly over the intended course to be taken by the boring device is disclosed herein. This technique utilizes an electromagnetic field which is emitted from the device and an above-ground arrangement for simultaneously sensing the strength of the field at a number of distinct points. The particular sensing points are selected so that the arrangment never has to leave the path directly above the boring devices intended course to locate the boring device, even if the latter deviates laterally from the path.

Abstract: An antenna assembly is provided for use in locating buried objects, particularly long thin objects such as pipes can be located, determining the position, and ascertaining the pipe direction by taking measurements from a single point, without mechanical movement of the antenna, and allowing a better suppression of spurious signals and reduction in false indications; which assembly has a plurality of antenna arms adapted and arranged to transmit and receive radiation into the ground and is characterized in that the arms have, on at least the surface nearest the ground, a cladding of a substantially lossless dielectric material, the relative permitivity of said dielectric being at least 3.5 and the thickness of said coating being at least .lambda..sub.d /20 where .lambda..sub.d is the wavelength of lowest frequency of the radiation to be transmitted from the antenna.

Abstract: A system for detecting the presence and depth of an object submerged in a medium having transmission characteristic substantially different than the atmosphere by means of receiving radiation from lighting incident to a reflected from the submerged object.

Abstract: A method and antenna assembly for transmitting into the ground polarizeable radiation whereby buried objects, and particularly long thin objects such as pipes can be located, the position determined, and the pipe direction ascertained, by taking measurements from a signle point, without mechanical movement of the antenna, and thereby allowing for good suppression of spurious signals and a reduction in false indications. The method includes the steps of transmitting into the ground polarizeable radiation, receiving reflected signals, indicative of the objects, incident upon at least two co-located angularly disposed transducers and comparing the signals thus received, wherein the radiation is transmitted from a transducer source which is co-located but angularly disposed with respect to each receiver transducer.

Abstract: This invention relates to a system for detecting submerged objects by receiving an incident indication of electromagnetic energy and also the reflection of said energy caused by the presence of a submerged object and to comapre the field strength of the incident radiation with the field strength of the reflected radiation to determine the relation therebetween, the relation being a measure of the object location.

Abstract: The location method uses relatively low frequency electromagnetic fields, e.g., 1-1000 Hz, for determining the relative position and/or orientation of a transmitting magnetic dipole antenna by using a vector field receiver. The transmitting antenna for subterranean location, is preferably a single axis, elongated solenoid with a ferromagnetic core. The receiving sensor may be a precise three-axis magnetic field detector of either a magnetometer or search coil type. Measurements are made for one or more positions of either the transmitter or receiver, or with one or more transmitters or receivers. The relative location of the transmitter and the receiver is calculated with respect to some known survey station by a method of successive approximations. The operating frequency is chosen to minimize field distortion from common steel structures, such as pipe, casing or railroad tracks, and to minimize field scattering such as from conducting inhomogeneities in the earth.