基于FPGA的多波束实时动态聚焦波束形成方法

提高多波束测深系统的综合精度，不仅需要提高远场精度，近场精度也不可忽视。针对常规多波束测深系统中采用远场近似模型，使得近场精度急剧下降的不足，研究了基于FPGA的多波束实时动态聚焦波束形成(RT-DFBF：Real-time Dynamic Focused Beam-forming)方法。该方法引入相移聚焦波束形成，论证其在多波束测深系统中解决近场问题的可行性，同时深入分析各个影响因素的实时处理情况，提出了一种基于FPGA的实时处理结构，该结构在输入通道为80个、采样率为28kHz、波束数为128个的条件下完成RT-DFBF。水池实验结果验证了该方法的实时性、有效性和实用性，具有重要工程应用价值。

Multi-beam Real-time Dynamic Focused Beam-forming Method based on FPGA

To increase the synthesized accuracy of the multi-beam sounding system not only requires to increase the far-field accuracy, but also not to neglect the near-field accuracy. In view of the adoption of the far-field approximation model in the multi-beam sounding system, it made the near-field accuracy sharply insufficient and multi-beam real time kinematic focused beam-forming method on the basis of FPGA was introduced. The method imported the phase shifting focused beam-forming, and proved its feasibility to solve the near-field problem in the multi-beam sounding system, meanwhile, profoundly analyzed the real time processing of each influential factor, and proposed a real time processing structure on the basis of FPGA, in which the structure completed RT-DFBF on the condition of 80 input passages, sampling rate of 28kHz and 128 beams. The pool experiment result testifies the effectiveness and feasibility of the method, and possesses some engineering value.