System using spread spectrum modulation for locating underground objects
First Claim
Patent Images
1. A method of locating an underground electrically conductive object comprising the steps of:
- a) applying an electrical signal to the object at one location on the object, the electrical signal being modulated by spread spectrum using a code unique to the object, b) detecting radiated signals from the object, c) demodulating the detected signals using the code unique to the object to identify signals radiated by the object, and d) processing the demodulated signals to locate the object.
1 Assignment
0 Petitions
Accused Products
Abstract
The location of underground objects such as pipes and conduits are located by detecting electrical signals emitted by the underground objects where the radiated signals include spread spectrum modulated RF signals. The system can operate in a passive or active mode, and in the active mode pseudo-noise (PN) generators can be employed or frequency-hopping can be employed. The use of spread spectrum minimizes or eliminates conflicting signals radiated from a plurality of underground objects and can improve signal to noise ratio of the detected signals.
69 Citations
16 Claims
-
1. A method of locating an underground electrically conductive object comprising the steps of:
-
a) applying an electrical signal to the object at one location on the object, the electrical signal being modulated by spread spectrum using a code unique to the object, b) detecting radiated signals from the object, c) demodulating the detected signals using the code unique to the object to identify signals radiated by the object, and d) processing the demodulated signals to locate the object. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. Apparatus for locating an underground electrically conductive object comprising:
-
a) a transmitter for applying an electrical signal to the object at one location on the object, the electrical signal being modulated by spread spectrum using a code unique to the object, b) a detector for detecting radiated signals from the object, c) a demodulator for demodulating the detected signals using the code unique to the object to identify signals radiated by the object, and d) a processor for processing the demodulated signals to locate the object. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14, 15, 16)
-
Specification