海事物联网中多波束卫星天线的实现机制

Multi-beam Antenna Implementation Scheme in Satellite-based Maritime Internet of Things

船舶自动识别系统是构建海事物联网信息平台的关键技术。在船舶自动识别系统中多天线收发方式不仅天线数量多、构造复杂且造价高,而且天线张角越大,边缘功率损失严重。此外,随着船舶数量的增加,在天线覆盖区域船舶发送信号之间的冲突急剧增长,极大地影响了解调概率。为解决该问题,提出了星载船舶自动识别系统中一种单天线多波束的实现机制,并以四波束为例,以较高增益覆盖较大地面区域,并利用波束间频率复用的方式有效降低了波束间的信号冲突,从而提高检测概率。检测概率的仿真结果表明了多波束机制相对于多天线系统的优势。

Automatic identification system（AIS） is a key technology in establishing the information platform for maritime Internet of Things.In AIS,multi-antenna system is characterized by large number of antennas,high cost and high complexity.And the larger the antenna angle is,the larger the loss of edge power becomes.Besides,the conflicts between signals from ships increase dramatically as more and more ships get in the antenna coverage area,which decreases the detection probability seriously.In order to solve this problem,a multi-beam antenna implementation scheme is proposed in satellite-based AIS.Take a four-beam application for example,the presented scheme covers larger ground areas with high gain and effectively reduces the signal conflicts between beams through inter-beam frequency reuse.Simulation result of the detection probability shows the superiority of the multi-beam scheme over multi-antenna systems.