Network system for wide area DGNSS

A differential global navigation satellite system (DGNSS) is always used to broadcast augmentation messages for GNSS to receivers in the covering areas through geostationary earth orbit (GEO) satellites to improve the accuracy, reliability, and integrity of navigation. GEO broadcasting is an efficient strategy for avionic applications and other modes of transport. For some applications though, it may be of interest to broadcast additional augmentation messages through other transmission means. For instance, it may be difficult for GEO reception in cities or indoors because of building obstacles. Real-time broadcasting of navigation augmentation messages through the internet is an important hot-spot of research. Based on characteristics of navigation augmentation messages, combined application layers multicast with i3 (internet indirection infrastructure) multicast, is presented herein with a hierarchy mix multicast system based on node heterogeneity to broadcast differential correction messages. The qualities of the system network structure are analyzed. After the securities requirements are analyzed, the types and solutions of security issues were briefly studied.