Advanced drill string communication system and method
A drill string communication system is described. An uphole transceiver can couple a signal onto the drill string at a power that is always greater that a selectable power for a downhole signal. Communication from a drill rig to an inground tool can be re-initiated using a maximum uphole transmit power of an uphole transceiver. A procedure can establish a new set of transmission parameters for a drill string signal to establish communication between the drill rig and the inground tool. The system can include a walkover locator that receives an active/inactive status-controlled electromagnetic locating signal. Responsive to a locating signal degradation, a reconfiguration command can modify the locating signal. The uphole transceiver and a downhole transceiver can automatically modify at least one parameter of a downhole signal. An uphole receiver can apply a compensation response to a transferred signal to compensate for a drill string channel transfer function.
1. A walkover locator for use in a system which utilizes a drill string extending from a drill rig to an inground tool with the inground tool configured to transmit an electromagnetic locating signal, said walkover locator comprising:
a receiver configured to receive the locating signal and to detect a degradation of reception of the locating signal and to generate a signal loss command responsive to detection of said degradation; and
a telemetry transmitter for transmitting the signal loss command to the drill rig.
2. The locator of claim 1 configured to generate said signal loss command responsive to a loss of reception of the locating signal.
3. The locator of claim 1 configured to generate said signal loss command responsive to a predetermined degree of degradation of the locating signal.
4. The locator of claim 1 configured to initially perform a noise scan responsive to detecting said loss of reception to identify a new frequency for the electromagnetic locating signal.
5. The locator of claim 1 wherein the signal loss command identifies at least one of a new transmission power, a new carrier frequency, a new baud rate and a new modulation mode for the electromagnetic locating signal.