1 华北电力大学 控制与计算机工程学院，北京102206
2 北京中飞艾维航空科技有限公司，北京102600
为了解决目前复杂环境下电力线提取精度及鲁棒性低的问题，提出了一种基于激光点云的电力线自动提取方法。通过主成分分析确定输电线路的主方向，将长距离输电走廊划分为多个空间网格，以应对地形起伏变化时植被点云对提取算法的干扰；再通过一种自顶向下的全新滤波算法剔除每个空间网格的地物点，根据点云密度分布差异实现电力线和电塔的自动分离；另外,提出半径搜索算法对分离后的结果进行处理，得到单条电力线的激光点云数据。结果表明，所提出的方法对电力线的提取精度高达99.69%，针对不同连接塔型和不同地形都具有很好的鲁棒性。该研究在输电通道空间结构的自动分析领域以及智能巡检领域具有良好的工程应用价值。
激光技术 电力线自动提取 自顶向下滤波 半径搜索 复杂环境 laser technique automatic extraction of power line top-down filtering radius search complex environment
Author Affiliations
Abstract
1 Centre for Optical and Electromagnetic Research, National Engineering Research Center for Optical Instruments, Zhejiang University, Hangzhou 310058, China
2 Ningbo Research Institute, Zhejiang University, Ningbo 315100, China
In this paper, recent advances in underwater wireless optical communication (UWOC) are reviewed for both LED- and LD-based systems, mainly from a perspective of advanced modulation formats. Volterra series-based nonlinear equalizers, which can effectively counteract the nonlinear impairments induced by the UWOC system components, are discussed and experimentally demonstrated. Both the effectiveness and robustness of the proposed Volterra nonlinear equalizer in UWOC systems under different water turbidities are validated. To further approach the Shannon capacity limit of the UWOC system, the probabilistic constellation shaping technique is introduced, which can overcome the inherent gap between a conventional regular quadrature amplitude modulation (QAM) format and the Shannon capacity of the channel. The experimental results have shown a significant system capacity improvement compared to the cases using a regular QAM.
060.2605 Free-space optical communication 060.4080 Modulation 140.7300 Visible lasers 010.4450 Oceanic optics Chinese Optics Letters
2019, 17(10): 100012
