06755263 is referenced by 35 patents and cites 2 patents.

Systems and methods for sensing at an underground drilling device in communication with an above-ground locator involve transmitting a radar probe signal from the underground drilling device. A radar return signal is received at the underground drilling device. The radar return signal is processed at the underground drilling device to produce sensor data. The sensor data is transmitted in a form suitable for reception by the above-ground locator.

Title
Underground drilling device and method employing down-hole radar
Application Number
10/283006
Publication Number
6755263 (B2)
Application Date
October 29, 2002
Publication Date
June 29, 2004
Inventor
Hans Kelpe
Pella
IA, US
Gregg A Austin
Pella
IA, US
Brian J Bischel
Hartland
WI, US
Kevin L Alft
Pella
IA, US
Agent
Crawford Maunu PLLC
US
Assignee
Vermeer Manufacturing Company
IA, US
IPC
E21B 7/04
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