MEASUREMENT-WHILE-DRILLING MUD PULSE TELEMETRY REFLECTION CANCELATION

摘要

Method and apparatus for optimizing mud pulse telemetry data rate by processing a sequence of measured pulses to minimize adverse effects of pressure pulse reflections, attenuations and distortions. A downhole telemetry unit cooperating with a sensor and disposed in a MWD or LWD logging tool generates a sequence of pulse within the mud column. The sequence is encoder to represent the response of the sensor disposed within the logging tool. The encoded pulse sequence is sensed at the surface of the earth using a pressure transducer. The output of the transducer yields an electrical signal that is typically attenuated and can contain reflections and distortions. This measured signal output is processed to minimize the effects of pulse reflections, attenuations and distortions thereby yielding a primary pulse sequence that is more representative of the response of the sensor and allowing an increase in mud pulse telemetry data rate.