Patent ID: 8654609

Claim:
A target detection device for detecting a target existing in a propagation environment, which detects the target by using a forward scattered wave scattered forward from the target, the device comprising: a sound source which projects a sound pulse within the propagation environment; a transducer array disposed in a region for receiving a forward scattered wave scattered forward from an object existing in the propagation environment; an addition processing unit, implemented by a computer processor, configured to extract only a signal of the forward scattered wave by applying vector addition processing on a reference signal scattered forward from an obstacle in a reference sound field received by the transducer array under a state where an obstacle exists in the propagation environment and a mixed signal in a mixed sound field received by the transducer array under a state where the target exists in the propagation environment in addition to the obstacle; a phase conjugation determination unit, implemented by the computer processor, configured to check whether or not a phase conjugacy is established in the propagation environment from the sound source to the transducer array by receiving the signal of the forward scattered wave extracted by the vector addition processing performed by the addition processing unit and employing a passive phase conjugation for determining the reference sound field; and a time reversal processing unit, implemented by the computer processor, configured to generate a time-reversed time reversal signal by applying time reversal processing on the forward scattered wave, on condition that the phase conjugation determination unit judges that the phase conjugacy is established.