能量加权时间特征用于浅海声源深度类型判别

针对浅海水面与水下低频宽带脉冲声源深度类型判别问题，提出了一种水平线列阵接收时利用能量加权到达时间特征判别声源深度类型的方法，并给出了工作频段选择的方法。该方法在脉冲宽度内以能量作为权值，对到达时间加权平均，将时间加权平均值与脉冲到达接收阵初始时间值的差值作为评判量，定义合适的水面与水下声源深度界限后，将评判量与拷贝声场中深度界限对应阈值比较，实现声源深度类型判别。经仿真数据验证，方法在等声速、负梯度、温跃层水文环境下的近距离声场均可实现。分析了声源距离、声源方位、海深、水平阵接收深度及阵列孔径等参数对方法性能的影响，进一步分析了声源距离失配、海底纵波声速失配、海深失配时方法的鲁棒性。除海底纵波声速失配时的影响较大外，方法具有较好的鲁棒性。

Application of energy-weighted time feature to source depth type discrimination in shallow water

Aiming at the discrimination of surface and underwater low-frequency broadband pulse source depth in shallow water waveguide, an approach based on the feature of energy weighted arrival time at the horizontal linear array is proposed. Moreover, the selection method of working frequency band is introduced. In the pulse duration, the energy is taken as the weight and the arrival time is weighted average. Taking the difference between the weighted average of arrival time and the initial time of pulse arrival receiving array as judgment and defining suitable depth boundary between surface and underwater source, the depth type of source can be discriminated by comparing the difference with the corresponding discriminant threshold of the boundary in the copying field. The simulations show that the approach all can be achieved in the hydrological condition of iso-speed velocity, negative gradient velocity and thermocline at close range field. The influence of the parameters such as source range and azimuth, sea depth, horizontal array receiving depth and array aperture on the performance is analyzed. Furthermore, the robustness for mismatch of source range, bottom longitudinal wave velocity and sea depth is analyzed. Except the mismatch of bottom longitudinal wave velocity, the proposed approach has good robustness.