1 1.1 GNSS GNSS: Global Navigation Satellite Systems GPS 3 L5 GLONASS FDMA CDMA Galileo BeiDou GNSS 1.2 SBAS GNSS SBAS: Satellite Based Augmentation System GNSS GNSS GNSS SBAS GNSS GNSS SBAS GPS L1 SBAS GNSS L5 2 SBAS 1.3 SBAS SBAS 1 GPS L5 CNAV: Civil Navigation Message SBAS SBAS LNAV: Legacy Navigation Message CNAV SBAS CNAV LNAV CNAV CNAV LNAV [1][2] CNAV GPS SBAS CNAV CNAV SBAS L5 I-Q 2 SBAS 2.1 SBAS SBAS ICAO [3] GPS SBAS GPS L1 L1-C/A 1 GPS GPS 2.1
GPS GPST 1 GPS 2.2 SBAS SBAS GNSS ICAO SBAS IWG: Interoperability Working Group SBAS SBAS IWG SBAS ICD: Interface Control Document[4] SBAS GNSS GPS GLONASS GalileoBeiDou GNSS MC: Multi- Constellation L1 L5 2 DF: Dual-Frequency 2.2MC DF GNSS SBAS SBAS DF 2.3 SBAS SBAS IWG SBAS 1 SBAS SBAS GPS L1-C/A LNAV: Legacy Navigation Message SBAS L5 CNAV: Civil Navigation Message LNAV 2 2.1 SBAS 2.2 SBAS 3 GPS GPST L1-C/A L5 LNAV CNAV GPS
3.1 Legacy Navigation Massage (LNAV) LNAV GPS L1 1575.42 [MHz] L1-C/A 50 [bps] GPS SBAS 3.1 15 t oe 3 t oc GPS ICD[5] LNAV IOD: Issue of Data 3.2 Civil Navigation Massage (CNAV) CNAV L5 1176.45 [MHz] I In-phase L5I5 50[bps]2013 [7]CNAV GPS L5 ICD[6] L5 L5I5 Q Quadrature-phaseL5Q5 CNAV L5I5 L5I5 L5Q5 [8]CNAV L5I5 L5Q5 CNAV LNAV 3.1 LNAV 3.2 3.1 A A REF = 26,559,710 [m]a (3.1)LNAV IOD CNAV 2 A A A REF (3.1) 3.2 (3.2)(3.3) t k A k n k t oe n 0 t oe [SC/s] A k AREF A A t k toe (3.2) 1 nk n0 n0 n 0 2 t k t oe 3.1 LNAV M 0 SC n 0 SC/s e - A m 0 SC i 0 SC SC W SC/s SC/s C uc rad C us rad C rc m C rs m C ic rad C is rad t oe s a f0 s a f1 s/s a f2 s/s 2 t oc s IOD - SC: semi-circles (1 SC = 180 deg =rad) 3.2 CNAV A REF m m/s 0 SC/s 2 LNAV A IOD (3.3) 4 CNAV CNAV SBAS CNAV CNAV L5 I-Q
4.1 SBAS CNAV CNAV IGS International GNSS Service[9]IGS Final 4.1 2015 11 9 0:002400GPST CNAV GPS Block-IIRM 7 PRN: 05, 07, 12, 15, 17, 29, 31 Block-IIF 10 PRN: 01, 03, 06, 08, 09, 24, 25, 26, 27, 30CNAV L2C L5 CNAV GPST 4.1.1 [1][2]GPS 4.1.2 SBAS CNAV 4.1.1 LNAV CNAV 4.1 RMSRoot Mean Square 4.2 4.1 4.2 LNAV CNAV 1 LNAV CNAV 4.1 GPS 6 PRN06 4.2 RMS 4.2 LNAV CNAV t oe t oe t oe 2 LNAV 04:00CNAV 03:30 4.2 4.2 PRN06 LNAV CNAV CNAV 1 LNAV 4.1 Radial orbit errors m 4.2 PRN06 4.1 IGS 2.5 cm 15 min RMS75 ps2.3 cm SDev20 ps0.6 cm 30 s 4.2 RMS LNAV CNAV m m m m 0.155 0.534 0.148 0.534 PRN06 0.073 0.129 0.071 0.087
LNAV CNAV RMS 4.3 4.2 4.3 4.2 CNAV LNAV 1 4.3 Block-IIRM Block-IIF PRN: 08, 24 LNAV CNAV 4.4 Block- IIF PRN: 06 4.2 RMS 4.4 4.2 t oe PRN06 LNAV CNAV CNAV t oe 1 4.1.2 SBAS CNAV SBAS CNAV SBAS 4.1.1 LNAV CNAV SBAS 4.1 4.3 SBAS SBAS ICD [4] 240 240 240 4.5 4.6 4.5 4.6 CNAV LNAV 12 [cm] SBAS 0.0625 [m] 0.03125[m]CNAV SBAS CNAV 4.3 Clock errors m 4.5 240 4.4 PRN06 CNAV LNAV 4.6 240
4.2 CNAV CNAV 3.2 CNAV L5 I L5I5CNAV L5I5 L5 Q L5Q5 L5Q5 CNAV L5Q5 SBAS DFMC 30 [10] 2 L5Q5 SBAS CNAV L5Q5 L5Q5 5 SBAS LNAV CNAV CNAV LNAV SBAS LNAV CNAV CNAV CNAV L5Q5 L5Q5 LNAV CNAV CNAV L5Q5 SBAS LNAV SBAS IWG LNAV SBAS [1] P. Steigenberger, O. Montenbruck, and U. Hessels, "Performance Evaluation of the Early CNAV Navigation Message", NAVIGATION, Vol. 62, No. 3, pp. 219-228, Fall 2015. H. Yin, Y.T. Morton, M. Carroll, and E. Vinande, "Performance Analysis of L2 and L5 CNAV Broadcast Ephemeris for Orbit Calculation", NAVIGATION, Vol. 62, No. 2, pp. 121-130, Summer 2015. [3] International Standards and Recommended Practices, Annex 10 to the Convention on Civil Aviation: Aeronautical Telecommunications, Vol. I, 6th Ed., July 2006. [4] SBAS IWG, Draft IWG SBAS L5 Interface Control Document (SBAS L5 ICD), Issue 1, Rev. 1 Draft 036, March 2015. [5] IS-GPS-200H, Interface Specification: Navstar GPS Space Segment/Navigation User Interfaces. [6] IS-GPS-705D, Interface Specification: Navstar GPS Space Segment/User Segment L5 Interfaces. [7] Global Positioning System Modernized Civil Navigation (CNAV) Live-Sky Broadcast Test Plan, NAVCEN, 30 May 2013. [8] J.H. Won, M. Anhileri, B. Eissfeller, A. Schmitz-Peiffer, an J.J Floch, "Optimum Data Rate and Signal Power Split for Next Generation GNSS Architectures," Proc. ION GNSS, pp. 2942-2955, September 2009. [9] International GNSS Service ( http://www.igs.org/ ) [10] GNSS 5 2010