A Computation Method of Differential Corrections for Virtual Maritime Reference Station Based on AIS

Abstract

In order to meet the performance requirement for differential GNSS services of International Maritime Organization (IMO) Resolution A. 915 (22) and International Association of Lighthouse Authorities (IALA), this paper focuses on a computation method of differential corrections for Virtual Maritime Reference Station (VMRS) based on Automatic Identification System (AIS) network. The VMRS is a reference station that can perform the functionality of maritime differential GPS (MDGPS) through marine mobile communication network such as Automatic Identification System (AIS), Wireless LAN, digital trunked radio system (TRS), mobile communications for maritime service. In case of this study, it discusses a method for generating the optimized differential corrections for onboard systems using the communication network. Therefore it proposes an algorithm for generating the differential corrections at the VMRS based on AIS shore station, and performs the performance assessment of the proposed algorithm based on DGPS corrections data measured from a DGPS reference station. First of all, the Virtual Maritime Reference Station (VMRS) and its functionalities are briefly introduced. The core of this study is the algorithm that can reproduce the differential corrections at the VMRS, receiving the differential corrections from near DGPS reference station using the communication network. Therefore, method to analyze its performance and to set its tuning is introduced. Finally, the paper discusses the performance test result and efficiency of the proposed method for the VMRS based on AIS.