Channel modelling and characterization for mud pulse telemetry

A Review of Communication Technologies in Mud Pulse Telemetry Systems

“…This model takes into account the influence of pipeline connection nodes and the impedance mismatch caused by the connection of end-of-drill string equipment, and it can effectively predict signal attenuation and reflection within the drill pipeline. Jia et al [46] considered the influence of boundary layer thickness on viscous friction and the effect of pipeline materials on characteristic impedance and proposed a frequency-domain transfer function model for mud pulse channels based on the 2D Navier-Stokes equations and distributed transmission line theory. This model is suitable for analyzing the attenuation, superposition, and dispersion caused by multipath reflections in low-frequency and high-frequency mud pulse signals.…”

“…During the propagation of mud pulse signals in the drill pipeline, power loss occurs due to the viscous dissipation and friction of the borehole wall, which is influenced by various factors such as well depth, mud viscosity, mud density, signal frequency, drill pipeline diameter, the number of drill pipeline sections, and annular clearance [46,47].…”

“…High-frequency components are more attenuated than low-frequency components, causing different frequency components of the signal to propagate at different speeds, and the time-domain signal will be smeared, resulting in signal dispersion. Therefore, it is possible to lower the carrier frequency appropriately, reduce mud viscosity by raising the mud temperature [46] or injecting nitrogen, and employ more advanced signal processing techniques to mitigate signal attenuation and improve the SNR of the received signal.…”