340 / | HD | COMMUNICATIONS: ELECTRICAL |
853.1 | DF | WELLBORE TELEMETERING OR CONTROL (E.G., SUBSURFACE TOOL GUIDANCE, DATA TRANSFER, ETC.) {14} |
854.3 | DF | .~ Using a specific transmission medium (e.g., conductive fluid, annular spacing, etc.) {4} |
854.6 | .~.~ Electromagnetic energy (e.g., radio frequency, etc.) {2} | |
854.7 | DF | .~.~.~> Optical link (e.g., waveguide, etc.) |
854.8 | DF | .~.~.~> Near field coupling (e.g., inductive, capacitive, etc.) |