Abstract:
Emergence of low radiation stealthy submarines poses a serious challenge to conventional sonar detection techniques.As an effective countermeasure,low frequency active sonar and the related detection techniques have become a research focus.In the complex and hostile opera-ting environments,active sonar detection faces serious difficulties.As a result,much attention has been given to the improvement of detection performance by exploiting underwater channel characteristics and/or background interferences.Promising results have been obtained.Techniques such as model-based processing,generalized matched filtering,reverberation elimination,combined signals and waveform fusion provide significant performance gain.With a better understanding of ocean environments,more precise and robust acoustic models are established.Model-based detection techniques will find their ways to practical applications.Before that happens,quasi model-based techniques such as RCI/SRC will be applied first due to the modest improvement over the classical detection methods,and the merits such as robustness,portability and ease of implementation.Mean-while,combination of these techniques,e.g.,combination of combined signal and waveform fusion,and SRC/RCI,etc.,are also feasible.