A system and method in accordance with the invention communicator remotely
with remotely controllable down hole tools in a well bore at a drilling
installation. At the surface, high energy pressure impulses directed into
the tubing or the annulus, or both, being at a level to propagate through
an interface between very different impedances zones, such as an upper
level gas zone and a lower level of mobile fluid media extending down
into the desired downhole location. The pressure impulses, provided by
directionally gating along the longitudinal confining path a pressure
impulse initially having sharp leading and trailing edges, reach the
downhole location as physical perturbations forming a discernible pattern
that can be detected by one or more energy responsive transducers. With
combinations of these signals, one of a number of separate control
devices can be remotely actuated. The system avoids the need for physical
or electrical connections and concurrently greatly reduces the likelihood
of accidental operation.