Electromagnetic telemetry in measurement while drilling with a wireless relay network

A novel electromagnetic telemetry (EMT) method for measurement-while-drilling operations is presented in this work. Electromagnetic (EM) telemetry is used to transfer downhole data to the surface in a measurement-while-drilling (MWD) operation. We discuss various stages of designing a small transceiver that can relay MWD data as EM signals inside the drill pipe. A microstrip loop antenna designed for this application as well as simulation and experimental results are also presented.;The MWD logging tool measures the geophysical properties of the formation that are critical in understanding the downhole environment. The existing telemetry techniques are tool specific and suffer from low data rate. Advancement of MWD logging technology and the increasing volume of the data they record at any given movement have magnified the need for a high data rate telemetry technique.;The goal of this research was to show that electromagnetic telemetry can be achieved by utilizing small stationary or floating RF transceivers inside the drill pipe. The MWD data collected at the bottom of the well can be transferred to the surface by utilizing a large quantity of these transceivers inside the drilling string. This method can achieve high data rates of up to one mega bits per second, which was impossible with the conventional telemetry technique or with low frequency electromagnetic (EM) telemetry methods. The small transceivers built for this project were tested in air, and a drilling pipe filled with air and vegetable oil, to prove their application in EMT. Being able to transmit data inside a metal pipe, this method can also be used for production control in developed oil fields.