Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
KDDI Corp
Original Assignee
Kokusai Denshin Denwa KK
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kokusai Denshin Denwa KKfiledCriticalKokusai Denshin Denwa KK
Priority to JP61278684ApriorityCriticalpatent/JPS63133809A/ja
Publication of JPS63133809ApublicationCriticalpatent/JPS63133809A/ja
Publication of JPH0424928B2publicationCriticalpatent/JPH0424928B2/ja
Method and apparatus for providing permanent magnetic signatures in buried cables and pipes to facilitate long-range location, tracking and burial depth determination