Internationale Zeitschrift für Sensornetzwerke und Datenkommunikation

Strain Sensor and Accelerometer Communication Channels in Drill Pipes: Delay Spreads and Eigen values

Abstract

Ali Alenezi* and Ali Abdi

Wireless data communication between downhole equipment and surface platform in oil wells is of high importance for
successful and cost effective drilling operations. In this letter two types of sensors, an accelerometer and a strain sensor
are considered as receivers of modulated acoustic signals propagated through steel pipes of drill strings in oil wells.
An accelerometer measures particle acceleration whereas a strain sensor measures fractional particle displacement.
Using measured channel impulse responses, two important characteristics of wireless acceleration and strain channels,
delay spreads and eigenvalues are studied. The experimental results show that strain channels exhibit smaller delay
spreads and larger eigenvalues. Therefore, they can provide lower bit error probabilities and better communication
performance for data transmission and telemetry. The results are useful for implementing improved systems for wireless
data communication through drill strings in oil wells.