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                                              Welcome to the CAS DATA CENTER
                                              

          DIRECTORY                                                               COMMENT
  The main directories are: https://data.bdsmart.cn/pub/

    pub/campaign/                                                  GNSS data from selected campaigns
                /bdgim/                                            BeiDou Global Ionospheric delay correction Model
                      /cnav/YYYY                                   Next-generation navigation messages for year YYYY
                /brdion/
                /shao/
    pub/data/
                /igs/
                    /lnav/YYYY/                                    Traditional navigation messages
                    /YYYY/DDD/                                     Daily GNSS observation with RINEX V3+ standards for year YYYY and doy DDD    
                    
    pub/product/ 
                /bias/                                             Multi-GNSS signal bias productŁ¨OSB/DCBŁ©
                     /YYYY/
                     /daybias/YYYY/
                     /monthbias/YYYY/
                     /weekbias/YYYY/ 
                /gnss/
                     /antex/                                       IGS antex file
                     /CODE/
                          /YYYY/DDD/                               Precise GNSS products from CODE include ERP,BIA,SP3,CLK
                     /GFZ/
                         /YYYY/DDD/                                Precise GNSS products from GFZ include ERP,BIA,SP3,CLK
                     /WHU/
                         /YYYY/bias/                               Precise GNSS products from WHU include BIA
                         /YYYY/clock/                              Precise GNSS products from WHU include CLK
                         /YYYY/orbit/                              Precise GNSS products from WHU include SPE,ERP
                /iono/
                     /ionex/YYYY/DDD
                     /ionsh/
                             
                /rts/
                    /brdc/YYYY/                                   CAS combined ephemeris
                    /iono/YYYY/DDD/                               
                    /rtpp/YYYY/                                   Real-Time SSR correction data from CAS,include SP3,CLK,OSB
                    /trop/
                /ultrarapid/WWWW/                                 GNSS 2-hour ultrarapid orbits from CAS for GPS week WWWW
                    
 
 
                  All files are archived in UNIX compressed format        
        
                  Contact CAS IGS DATA CENTER (https://igs.bdsmart.cn) for further information.
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