The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 1989
Filed:
Mar. 27, 1987
David J Gunton, Stakeford, GB;
Lucy J Manning, Tyne, GB;
British Gas plc, London, GB;
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.