European GNSS (Galileo) open service (797926), страница 4
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i-iiOS SIS ICD, Issue 1.2, dd.mm 2014xlicForPubTable 81.xitionsultaAFCoTnSAR Field Bit Structure......................................................................................................................................................................38RLM Identifier Description...............................................................................................................................................................38SAR Short RLM......................................................................................................................................................................................38SAR Long RLM.......................................................................................................................................................................................39Spare SAR Data....................................................................................................................................................................................39Ephemeris Parameters.....................................................................................................................................................................41User Algorithm for Ephemeris Determination.....................................................................................................................42GST Parameters...................................................................................................................................................................................42Galileo Clock Correction Parameters........................................................................................................................................43Galileo Clock Correction Data.......................................................................................................................................................43BGD Parameters...................................................................................................................................................................................44BGD Values Mapping on Messages and Services..............................................................................................................45Ionospheric Correction Parameters...........................................................................................................................................45Parameters for the GST-UTC Conversion...............................................................................................................................46Parameters for the GPS Time to GST Offset Computation..........................................................................................47Satellite ID...............................................................................................................................................................................................47IOD Values Mapping on Data Type............................................................................................................................................48Data Validity Satellite Status (transmitted on E5a).........................................................................................................48Data Validity Satellite Status (transmitted on E5b and E1-B)...................................................................................48Data validity Status Bit Values....................................................................................................................................................49Signal Health Status for E5a (transmitted on E5a).........................................................................................................49Signal Health Status for E5b and E1 (transmitted on E5b and E1-B)...................................................................49Signal Health Status Bit Values...................................................................................................................................................49Almanac Parameters.........................................................................................................................................................................51SISA Index Values................................................................................................................................................................................51SISA Parameters..................................................................................................................................................................................51SAR RLM Message Code Values..................................................................................................................................................52SAR Short-RLM Data Values..........................................................................................................................................................52Example for the Translation of Logical (binary) Spreading Code into HexadecimalRepresentation......................................................................................................................................................................................56Primary Code-Length and Hexadecimal Representation Characteristics for theGalileo Signal Components............................................................................................................................................................56DRTable 52.Table 53.Table 54.Table 55.Table 56.Table 57.Table 58.Table 59.Table 60.Table 61.Table 62.Table 63.Table 64.Table 65.Table 66.Table 67.Table 68.Table 69.Table 70.Table 71.Table 72.Table 73.Table 74.Table 75.Table 76.Table 77.Table 78.Table 79.Table 80.© European Union 2014Document subject to terms of use and disclaimers p.
i-iiOS SIS ICD, Issue 1.2, dd.mm 20141. Introduction1.1. Document ScopeThe name “Galileo” shall mean the system established under the Galileo programme.tionThe present European GNSS (Galileo) Open Service Signal In Space Interface ControlDocument (OS SIS ICD) Issue 1.2 contains the publicly available information on the GalileoSignal In Space. It is intended for use by the Galileo user community and it specifies theinterface between the Galileo Space Segment, and the Galileo User Segment.The present document is organised as follows:ltaAFCoTn1.2. Document Overviewsu●● Chapter 1 is this introduction which provides the scope of the document and anoverview of the Galileo system●● Chapter 2 provides the signal-in-space radio frequency characteristics●● Chapter 3 provides the characteristics of the spreading codes●● Chapter 4 provides the message structures●● Chapter 5 provides the characteristics of the navigation message data contentsDR1.3.
Galileo System OverviewGalileo is the European global navigation satellite system providing a highly accurate, andglobal, positioning service under civilian control. It is interoperable with GPS and GLONASS,the two other current global satellite navigation systems.licThe fully deployed Galileo system consists of 24 operational satellites and up to 6 activespares, positioned in three circular Medium Earth Orbit planes. Each orbit has a nominalaverage semi-major axis of 29 600 km, and an inclination of the orbital plane of 56degrees with reference to the equatorial plane.ubGalileo provides enhanced distress localisation and call features for the provision of aSearch and Rescue (SAR) service interoperable with the COSPAS-SARSAT system.ForPFigure 1 specifies the radio-frequency air interface between space and user segments.Three independent CDMA signals, named E5, E6 and E1, are permanently transmitted byall Galileo satellites.
The E5 signal is further sub-divided into two signals denoted E5a andE5b.Figure 1.Space Vehicle/NavigationUser Interface© European Union 2014Document subject to terms of use and disclaimers p. i-iiOS SIS ICD, Issue 1.2, dd.mm 201412. Galileo Signal Characteristics2.1.1. Frequency Bandstion2.1. Frequency PlanDRsultaAFCoTnThe Galileo navigation Signals are transmitted in the four frequency bands indicated inFigure 2. These four frequency bands are the E5a, E5b, E6 and E1 bands.
They provide awide bandwidth for the transmission of the Galileo Signals.Figure 2.Galileo Frequency PlanlicThe Galileo frequency bands have been selected in the allocated spectrum for RadioNavigation Satellite Services (RNSS) and in addition to that, E5a, E5b and E1 bands areincluded in the allocated spectrum for Aeronautical Radio Navigation Services (ARNS),employed by Civil-Aviation users, and allowing dedicated safety-critical applications.ub2.1.2. Carrier FrequenciesForPGalileo carrier frequencies are shown in Table 1. The names of the Galileo signals are thesame than the corresponding carrier frequencies.SignalCarrier Frequency (MHz)E11575.420E61278.750E51191.795E5a1176.450E5b1207.140Table 1.
Carrier Frequency per SignalNote: The E5a and E5b signals are part of the E5 signal in its full bandwidth.2.1.3. Receiver Reference BandwidthsThe receiver reference bandwidths centred on the carrier frequencies of Table 1 arespecified in Table 2. Those reference bandwidths are considered when computing thecorrelation losses provided in paragraph 2.8.2© European Union 2014Document subject to terms of use and disclaimers p. i-iiOS SIS ICD, Issue 1.2, ?????????? 2014SignalReceiver Reference Bandwidth(MHz)E124.552E640.920E551.150E5a20.460E5b20.4602.2. Signal PolarizationtionTable 2.
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