05065098 is referenced by 81 patents and cites 30 patents.

A locating system has its performance enhanced by the use of digital filtering. The locating system may include a transmitter for transmitting an electromagnetic signal from a concealed object. The locating system may also use electromagnetic signals from existing electromagnetic sources unrelated to the locator system. A receiver is provided for receiving a selected electromagnetic signal. The signal is subsequently converted from an analog signal into a digital signal and subjected to digital filtering. The resulting digital signal is then processed to provide location information about the concealed object.

Title
System for locating concealed underground objects using digital filtering
Application Number
7/539847
Publication Number
5065098
Application Date
June 18, 1990
Publication Date
November 12, 1991
Inventor
Leslie D Hoy
Knoxville
TN, US
Lloyd N Salsman
El Reno
OK, US
Agent
Banner Birch McKie & Beckett
Assignee
The Charles Machine Works
OK, US
IPC
G01V 3/165
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