星载AIS多网冲突技术研究

Satellite-based AIS(Automatic identification system) can detect the information(identity,position,velocity,course,etc.) of ships from space with a large coverage. For the large FOV(Field of View) of antenas,the system will receive many AIS meassages from multiple SOTDMA cells at the same time-slot, then generate message-collisions and result in a low signal detection probability.This project aims at solving the multi-cells message-collisions problem and enhancing the signal detection probability. Mechanism of multi-cells message-collisions, establishment of the message-collisions model and analysis on the signal detection probability with consideration of the global vessels distribution will be studied at first to put a solid foundation about this research. Several technical items would be proposed and studied, such as blind source separation method, small-size smart antenna, digital channlized receiver, in order to reduce the AIS message-collisions. This project has great significance to the future applied space-based AIS system.

星载AIS可为大范围海域内的船只身份、位置、速度、航向等信息的探测提供天基手段，但由于其天线的波束覆盖范围大，会同时收到多个自组织网络的AIS信号，引起多网冲突问题，导致信号检测概率下降。本项目拟通过对星载AIS多网冲突的机理分析，建立完备的信号冲突模型，提炼其特征，并结合全球海域的船只密度分布完成全球海域的检测概率分析；研究多网冲突问题和提高信号检测概率的关键技术，如盲源分离、小尺寸智能天线、数字信道化侦收等，探索多种可行的技术方案，减缓和解决AIS信号冲突，大幅提高星载AIS的单轨信号检测概率，实现全球任意海域的AIS侦收。项目研究对未来建设实用的星载AIS侦收系统具有重大意义。

星载AIS可为大范围海域内的船只身份、位置、速度、航向等信息的探测提供天基手段，但由于其天线的波束覆盖范围大，会同时收到多个自组织网络的AIS信号，引起多网冲突问题，导致信号检测概率下降。本项目通过对星载AIS多网冲突的机理分析，建立完备的信号冲突模型，提炼其特征，并结合全球海域的船只密度分布完成全球海域的检测概率分析；研究了多网冲突问题和提高信号检测概率的关键技术，如盲源分离、小尺寸智能天线、数字信道化侦收、星载AIS接收系统和微纳卫星星座设计等，探索多种可行的技术方案，减缓和解决AIS信号冲突，大幅提高星载AIS的单轨信号检测概率，实现全球任意海域的AIS侦收。项目研究对未来建设实用的星载AIS侦收系统具有重大意义。相关成果已应用在天拓三号、海洋一号C/D星载AIS载荷。