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To comprehensively evaluate the services provided by the BeiDou Navigation Satellite System( BDS-3), a concept of Quality of Service (QoS) in network communication is introduced and then a QoS hierarchical model is proposed. A preliminary classified evaluation index design is given, covering BDS-3 services of Radio Navigation Satellite Service (RNSS), Satellite-Based Augmentation System ( SBAS), Precise Point Positioning (PPP), Regional Short Message Communication ( RSMC), Global Short Message Communication( GSMC),Search and Rescue ( SAR) and Ground Augmentation System( GAS).Then the service guarantee mechanism and parameters mapping relation-ship are analyzed, thus to provide a way to optimize multiple QoS indicators in complex conditions and quickly locate the source of the fault in abnormal conditions. The research results are expected to provide references for the comprehensive evaluation of BDS performance. [ABSTRACT FROM AUTHOR]

In view of the difficulties in data processing and adjustment of coordinate calculation perplexed large-scale GNSS reference station network, this paper proposes a coordinate calculation method. The method is elaborated in four aspects including selection of global framework sites, division of reference station network subnets, single-day data processing of base stations, and global network adjustment calculation. Finally, the internal and external consistence accuracies of the calculation results are evaluated. The analysis results show that the method can solve reference coordinates for network with more than 3 000 stations, and the RMSE of the results is better than 3 mm in both north-south and east-west directions, and better than 6 mm in elevation. The accuracy of the calculation is higher than those of most IGS analysis centers. [ABSTRACT FROM AUTHOR]