Abstract: A system can include a distributed acoustic sensing (DAS) system and a computing device coupled with the DAS system. The DAS system can include a pulse generator and a sensing fiber that can be positioned in a wellbore. The system can generate a light pulse to be transmitted into the sensing fiber to make one or more measurements relating to a wellbore operation involving the wellbore. The system can receive an initial pulse that includes a reflection of the light pulse prior to the light pulse entering the sensing fiber. The system can apply a cross-correlation filter to one or more subsequently received pulse reflections originating from the sensing fiber. The cross-correlation filter can include the initial pulse reflection or synthetic initial pulse. The system can generate, based on applying the cross-correlation filter, an output signal that can be used to control the wellbore operation.

Abstract: A method can be used to determine multi-phase measurements of fluid flowing with respect to a wellbore. Signals can be received, and the signals can be emitted by each variable frequency acoustic emitter of a set of variable frequency acoustic emitters positioned spaced apart in a sensing transducer that is in an interior of a wellbore. The received signals can be converted into a flow rate of each of a set of different fluid phases of a fluid in the wellbore. The multi-phase measurements of the fluid can be determined using the converted flow rate.

Abstract: A method can be used to determine multi-phase measurements of fluid flowing with respect to a wellbore. Signals can be received, and the signals can be emitted by each variable frequency acoustic emitter of a set of variable frequency acoustic emitters positioned spaced apart in a sensing transducer that is in an interior of a wellbore. The received signals can be converted into a flow rate of each of a set of different fluid phases of a fluid in the wellbore. The multi-phase measurements of the fluid can be determined using the converted flow rate.