Matched field postbeamformer interference canceller for towed linear array sonar

According to the response of the towed linear array to the noise from the tow ship, an approach named MFPIC (matched field postbeamformer interference canceller) is proposed to cancel this strong interference. Matched field processing (MFP) correlates the replica field and measured field, while MFPIC directly uses the replica field vector to generate interference beam. A distinct feature of the MFPIC is that it can suppress a noise source if the source-receiver geometry and the characteristics of the noise transmission channel are known a priori while the signal arriving from the same direction or in the vicinity of that direction can be completely preserved. For towed line array sonar system, MFPIC may provide significant improvement in tow-ship noise suppression, which in turn results in great performance enhancement, and particularly the dead zone of detection around the tow-ship direction can be eliminated. Experimental results based on simulated data for typical towed line array sonar have verified the theory and shown great potential of the approach.