为降低便携式三维成像声纳系统的硬件开销，同时保证阵列的波束性能，提出了 一种非网格化阵列稀疏方法． 该方法基于十字型阵列，在模拟退火算法中加入阵元位置扰 动，以实现对十字型阵列的非网格稀疏优化，降低阵元数量; 引入多频发射和并行子阵接 收波束形成算法，构建模拟退火算法中新的能量函数，以保证十字型稀疏阵列具有成像实 时性以及较低的计算需求． 最后利用该方法对 100 + 100 的十字型阵列进行稀疏优化． 实 验结果表明，该方法获得的非网格化稀疏阵列能够获得预设的波束性能，并具有成像的实 时性和较低的计算需求;与现有文献相比，在保持相同波束性能的条件下，该稀疏阵列具 有最少的阵元数量． 

A nongrid sparse array optimization method was proposed to reduce the hardware cost of the portable 3D imaging sonar system and guarantee the performance of beam pattern of the array． Based on the cross array， the element position perturbation was introduced into the simulation annealing ( SA) algorithm to achieve the nongrid sparse optimization for the cross array and decrease the element number． Based on multiplefrequency transmitting beamforming and parallel subarray receiving beamforming algorithms，a new energy function for the SA algorithm was defined to make the sparse cross array has a realtime imaging property and lower computational requirement． Finally， the proposed method was employed to optimize a cross array with 100 +100 elements． The experiment results demonstrate that the nongrid sparse array obtained by the proposed method can achieve the presupposed beam pattern performance and own realtime imaging property and low computational requirements． Compared with the existing literature， the sparse array has the fewest active elements while maintaining the same beam pattern performances．