Advanced passive interference management in directional drilling system, apparatus and methods

A portable device as part of a system in which a transmitter is configured to move through the ground in a region during an operational procedure while transmitting a depth signal, said portable device comprising:

• an antenna having an output;
• and
• a receiver configured to scan a plurality of frequencies within a depth signal frequency range that is below 1 KHz to measure the electromagnetic noise at each one of the plurality of frequencies based on the antenna output and identify a lowest one of the frequencies as a potential depth frequency which satisfies a low noise requirement.

A portable device as part of a system in which a transmitter is configured to move through the ground in a region during an operational procedure while transmitting a depth signal, said portable device comprising:

• an antenna having an output;
• and
• a receiver configured to measure the electromagnetic noise based on the antenna output in at least two different frequency bands below 1 KHz by incrementally scanning each frequency band to generate a plurality of incremental noise readings across each frequency band and to display one or more potential depth frequencies for each frequency band for selection by the operator based on the incremental noise readings.

A system, comprising:

• a transmitter that is configured to move through the ground in a region during an operational procedure while transmitting a depth signal at a depth frequency that is selectable in a depth signal frequency range below 1 KHz to provide at least some immunity to passive interference and which is also subject to electromagnetic noise that can vary within said region;
• and
• a portable device configured to measure the electromagnetic noise based on the antenna output in at least two different frequency bands below 1 KHz by incrementally scanning each frequency band to generate a plurality of incremental noise readings across each frequency band and to display one or more potential depth frequencies for each frequency band for selection by the operator based on the incremental noise readings.