Patent ID: 11906685
Assignee: MERLIN TECHNOLOGY GMBH
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 11:
12. In a region which contains at least first and second in-ground cables, each of which cables includes an electrically conductive component such that, when the first cable is driven at a locating signal frequency to emit a locating signal in an electromagnetic form, the locating signal can be coupled to the second cable in a way which causes the second cable to generate a false locating signal in electromagnetic form, an apparatus configured to discriminate between the locating signal and the false locating signal, said apparatus comprising:
a transmitter configured to generate said locating signal frequency for coupling onto the first cable and to transmit a reference signal as an electromagnetic reference signal, which contains said locating signal frequency impressed thereon, in a way which provides for detection of a phase shift between the locating signal and the false locating signal; and
a receiver configured to detect said phase shift and to distinguish the locating signal from the false locating signal based on the phase shift.