Boring Tool Tracking/Guiding System and Method with Unconstrained Target Location Geometry

In a system for tracking a transmitter within an underground region using a portable locator, in which system the transmitter is configured for transmitting a dipole locating signal and where the position of the transmitter is characterized, at least in part, by certain orientation parameters which are transmitted from the transmitter, a method comprising:

• from a first position, moving the transmitter to a second position during a time interval, said first position forming part of a first positional relationship relative to the portable locator at a locator position;
• with the transmitter at the second position, measuring a signal strength of the locating signal with the portable locator and receiving said certain orientation parameters from the transmitter with the portable locator;
• establishing a maximum movement value for the boring tool such that any potential movement of the transmitter over the time interval is less than the maximum movement value and saving the maximum movement value in the portable locator;
• and
• based on the first positional relationship, said certain orientation parameters, the maximum movement value and the measured signal strength of the locating signal as received by the portable locator with the transmitter at the second position, configuring the portable locator for determining a second positional relationship including the transmitter at the second position relative to the portable locator at the locator position.