Directional drilling communication protocols, apparatus and methods

A transmitter for use in conjunction with a receiver as part of a system for performing an inground operation in which a drill string extends from a drill rig to an inground tool which supports the transmitter such that extension and retraction of the drill string generally produces corresponding movements of the inground tool during the inground operation, said transmitter comprising:

• at least one sensor for sensing one or more operational parameters relating to the inground tool to produce a sensor signal;
• and
• a processor configured for detecting whether the inground tool is stationary or moving based on the sensor signal, and for transmitting data characterizing one or more of the operational parameters at a higher level of resolution when the inground tool is stationary and at a lower level of resolution when the inground tool is moving.

A transmitter for use in conjunction with a receiver as part of a system for performing an inground operation in which a drill string extends from a drill rig to an inground tool which supports the transmitter such that extension and retraction of the drill string generally produces corresponding movements of the inground tool during the inground operation, said transmitter comprising:

• at least one sensor for sensing one or more operational parameters relating to the inground tool;
• and
• a processor configured for transmitting a data signal using a plurality of packet communication protocols including a particular protocol that, responsive to detecting a stationary state of the transmitter, utilizes a fixed data frame to characterize the one or more operational parameters and repeatedly transmits the fixed data frame.

An apparatus for use in conjunction with a system for performing an inground operation in which a drill string extends from a drill rig to an inground tool such that extension and retraction of the drill string generally produces corresponding movements of the inground tool during the inground operation, said apparatus comprising:

• a transmitter configured to be carried proximate to the inground tool for sensing a plurality of operational parameters relating to the inground tool including a pitch orientation of the transmitter and for transmitting a data signal including a low resolution pitch packet responsive to detecting that the inground tool is moving and a high resolution pitch packet responsive to detecting that the inground tool is stationary;
• and
• a receiver for positioning at an aboveground location for receiving the data signal and for recovering the operational parameters.

An apparatus for use in conjunction with a system for performing an inground operation in which a drill string extends from a drill rig to an inground tool such that extension and retraction of the drill string generally produces corresponding movements of the inground tool during the inground operation, said apparatus comprising:

• a transmitter configured to be carried proximate to the inground tool for sensing a plurality of operational parameters relating to the inground tool including a roll orientation of the transmitter and for transmitting a data signal including a low resolution roll packet responsive to detecting that the inground tool is moving and a high resolution roll packet responsive to detecting that the inground tool is stationary;
• and
• a receiver for positioning at an aboveground location for receiving the data signal and for recovering the operational parameters.