Rectangular Microwave Waveguides for Subsea Communication in Oil and Gas Wells

In the drilling industry, communication between drilling rig and drill bit is of great importance, because of the necessity of data for process monitoring and control. In this paper, we examine the possibility of using rectangular waveguides outside the drill string in order to avoid contact with the medium transported in the drill string. The new developed watertight connection elements between waveguide segments were produced using injection molds made by additive manufacturing. First measurements at 20 GHz were carried out, which made it possible to estimate the distance between repeaters that would be necessary for data transmission over longer distances. These estimates were based on the worst measured attenuation (-3.77 dB/m) and best simulated attenuation (-0.40 dB/m).