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:
Jun. 20, 1995
Filed:
Mar. 31, 1994
Candido J Arroyo, Lithonia, GA (US);
Sungho Jin, Millington, NJ (US);
Thomas T Palstra, New Providence, NJ (US);
AT&T Corp., Murray Hill, NJ (US);
Abstract
The present invention relates to an optical fiber cable which includes magnetically locatable materials within the sheath system thereby allowing the cable to be located after it has been buried. More specifically, at least a portion of the magnetic particles are purposely oriented in a particular alignment based on their magnetic properties. Such an arrangement not only allows the generation of a detection signal which is distinguishable from that generated by a solid metallic pipe, but also can greatly enhance the level of the detection signal generated. The enhanced detection signal provides for more reliable detection of buried all-dielectric cables and also allows them to be located even when buried at greater depths, such as six feet or more. In specific embodiments of the present invention, the magnetic particles may be aligned and/or magnetized either longitudinally, vertically or transversely relative to the cable. Additionally, these various directions of alignment and magnetization may be alternated along the length of the cable to further enhance the detection signal generated in order to establish a means of accurately and cost-effectively locating communications cable after they are buried.