摘要
针对非均匀海杂波环境下弱小目标检测困难的问题,本文基于复值残差单元和注意力门机制,提出一种用于海杂波抑制的非对称编解码网络(Asymmetric Encoder-Decoder Network,AED-Net).该网络以雷达回波经匹配滤波后得到的复值信号为输入,利用复值残差单元取代常规卷积单元进行弱小目标和海杂波特征的提取,增强网络特征提取能力的同时避免特征信息退化.然后采用注意力门模块将编码路径各模块提取的特征信息分别送入到解码路径对应的模块.最终输出海杂波抑制后的复值信号.由于各注意力门的输入和输出维度可根据网络结构自主选择,该网络设计是一种非对称编解码结构.与典型对称编解码网络UNet相比,复值残差单元与注意力门的引入显著降低了特征信息的冗余度,增强特征信息的提取与传递,提升了海杂波抑制性能.与此同时,复值残差单元的参数规模远小于卷积单元,而注意力门的引入也有效减少解码路径单元的数量,整个网络的参数规模显著减小.基于海杂波实测数据的实验结果表明,与典型复值UNet(Complex Value-UNet,CV-UNet)网络相比,AED-Net的输出信杂比平均提升9 dB,有效工作的最低信杂比降低了3 dB,模型参数量和计算量分别减少57.8%、50%.
To address the challenge of weak target detection in nonhomogeneous sea clutter environments,this paper proposes an asymmetric encoder-decoder network(AED-Net)for sea clutter suppression based on complex-valued residual units and attention gates.The network takes the complex-valued signal generated by radar echoes passing through the matched filter as input.First,it replaces conventional convolutional units with complex-valued residual units to extract fea⁃tures of weak targets and sea clutter,enhancing the network’s capability of feature extraction while avoiding feature degra⁃dation.Then,attention gate modules are employed to selectively propagate the feature information extracted by each mod⁃ule in the encoding path to the corresponding modules in the decoding path.Finally,it yields the complex signal after sea clutter suppression as output.Due to the capability of independently selecting the input and output dimensions of each atten⁃tion gate according to the network structure,the proposed network has an asymmetric encoder-decoder structure.Compared to typical symmetric encoder-decoder network,UNet,the introduction of complex-valued residual units and attention gates significantly reduces the redundancy of feature information,enhances feature extraction and transmission,and thus im⁃proves the sea clutter suppression performance.Meanwhile,complex-valued residual units have much smaller parameter size than convolutional units and the introduced attention gates greatly reduce the number of units in the decoding path,re⁃sulting in a significant reduction of total network parameters.Experimental results based on real sea clutter data demonstrate that compared to the complex value-UNet(CV-UNet)network,AED-Net achieves an average improvement of 9 dB in the output signal-to-clutter ratio(SCR)and can effectively operate at a minimum SCR reduction of 3 dB.Moreover,the number of parameters and the computational cost are reduced by 57.8%and 50%,respectively.
作者
陈胜垚
胡晨康
程智勇
席峰
刘中
CHEN Sheng-yao;HU Chen-kang;CHENG Zhi-yong;XI Feng;LIU Zhong(School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing,Jiangsu 210094,China;School of Computer Science and Artificial Intelligence,University of Chaohu,Hefei,Anhui 238024,China)
出处
《电子学报》
EI
CAS
CSCD
北大核心
2024年第8期2628-2640,共13页
Acta Electronica Sinica
基金
国家自然科学基金(No.62171224)。
关键词
海杂波抑制
编解码网络
残差结构
注意力门
复值信号
sea clutter suppression
encoder-decoder network
residual unit
attention gate
complex-valued signal
