Galileo Os Sis Icd 230506

8/6/2019 Galileo Os Sis Icd 230506

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Reference: GAL OS SIS ICD/D.0Issue: Draft

Revision: 0

Date: 23/05/2006

Page 1

, 2006, European Space Agency / Galileo Joint Undertaking

Document subject to terms of use and disclaimers p. 2-4.

Galileo Open ServiceSignal In Space Interface Control Document

(OS SIS ICD)

Draft 0


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TERMS OF USE AND DISCLAIMERS

1. Authorised Use and scope of use

The Galileo Open Service Signal In Space Interface Control Document Draft 0 (hereinafter referred to as OS

SIS ICD) and theinformation contained hereinis made available to the public by the Galileo Joint Undertaking

(hereinafter referred to as Publishing Authority) for information, standardization and research and development

purposes for the benefit and the promotion of the European Global Navigation Satellite Systems programmes

(GNSS Programmes).

2. General disclaimer of liability as to the use

With respect to the OS SIS ICD and any information contained in the OS SIS ICD, neither the Publishing

Authority nor the copyright holders nor the generator of such information make any warranty, express or

implied, including the warranty of fitness for a particular purpose, or assumes any legal liability or responsibility

for the accuracy, completeness, or usefulness of any information hereby disclosed or for any product developed

based on this information, or represents that the use of this information would not cause damages or would not

infringe any intellectual property rights.

No liability is hereby assumed for any direct, indirect, incidental, special or consequential damages, including

but not limited to, damages for interruption of business, loss of profits, goodwill or other intangible losses,

resulting from the use for illegal purposes of the OS SIS ICD or of the information contained herein.

Liability is excluded as well for consequences of the use and / or abuse of the OS SIS ICD or the information

contained herein.


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3. Disclaimers as to Intellectual Property Rights

The information contained in the OS SIS ICD is subject to intellectual property rights (hereinafter referred to as

IPR).

3.1. Copyright

The OS SIS ICD is protected by copyright. Any alteration or translation in any language of the OS SIS ICD as a

whole or parts of it is prohibited unless the Publishing Authority provides a specific written prior permission.

The OS SIS ICD may only be partly or wholly reproduced and/or transmitted to a third party for non profit

purposes, in accordance with the herein described permitted use and under following conditions:

- the present Terms of Use and Disclaimers are accepted, reproduced and transmitted entirely and

unmodified together with the reproduced and/or transmitted information;

- the copyright notice , 2006, European Space Agency / Galileo Joint Undertaking is not removed

from any page.

3.2. IPR licence for research and development and standardization purposes

The use of the information contained in the OS SIS ICD, including the spreading codes which are subject to IPR

is hereby allowed exclusively for research and development or standardisation purposes in the frame of the

permitted scope of use described in Art. 1.

3.3. IPR licence for commercial use

Any use of the OS SIS ICD or of the information contained in the OS SIS ICD which does not fall under the

herein authorised use and scope is prohibited, unless a specific authorisation is obtained by the Publishing

Authority and/or the entitled party to the associated IPR. The prohibition includes specifically the use for

commercial exploitation of any kind of whatsoever of the OS SIS ICD or of the information contained herein,

the registering or protecting of IPR deriving or based on the OS SIS ICD or the information contained in the OS

SIS ICD as well as the use in conflict with the authorised scope as described in Art. 1.

It particular, any commercial use of the spreading codes protected by IPR through the reproduction, the making,

the sale or the import of the spreading codes and/or a product implementing these codes requires specific

licences.

Such licences will be provided on a non discriminatory basis in accordance with European community rules and

international commitments taken within the framework of the Galileo Programme.


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The detailed terms and conditions of such licences are not yet available. It is the intention of the Publishing

Authority and/or the holder of the associated IPR to provide commercial licences in due time for allowing theuse of the signals broadcasted by the first Galileo satellite in operation.

3.4. Miscellaneous

The publication or provision of the OS SIS ICD or the information contained herein shall not be construed as

granting any implied IPR licence.

No failure or delay in exercising any right in relation to the OS SIS ICD or the information contained herein

shall operate as a waiver thereof, nor shall any single or partial exercise preclude any other or further exercise of

such rights.

The disclaimers contained in this document are applying to the extent permitted by applicable law.

4. Updates

The OS SIS ICD is a draft and not definitive version. The OS SIS ICD in its current version is subject to

modification, update, and variations.

The publication of updates will be subject to the same terms as stated herein unless otherwise evidenced.

Although the Publishing Authority will deploy its efforts to give notice to the public for further updates of OS

SIS ICD, it does not assume any obligation to advice on further developments and updates of the OS SIS ICD,

nor to take into account any inputs, comments proposed by interested persons or entities, involved in the

updating process.

5. Further information

Should you need any further information in relation to the OS SIS ICD, please contact:

Galileo Joint Undertaking

Rue du Luxembourg, 3

1000 Brussels

BELGIUM

Email : [email protected]


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C H A N G E L O G

Reason for change Issue Revision Date

First issue Draft 0 19th May 2006


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TABLE OF CONTENTS

TERMS OF USE AND DISCLAIMERS ...................................................................... 2

1. SCOPE............................................................................................................ 12

2. INTRODUCTION............................................................................................. 13

3. LIST OF ACRONYMS..................................................................................... 14

4. DEFINITIONS AND NOMENCLATURE IN THIS DOCUMENT ...................... 17

5. GALILEO FREQUENCY PLAN ...................................................................... 19

5.1 Frequency bands .......................................................................................................... 19

5.2 Carrier frequencies and bandwidths.......................................................................... 19

5.3 Multiple Access ............................................................................................................. 20

6. GALILEO SIGNALS AND MAPPING TO SERVICES .................................... 21

7. GALILEO SIGNALS CHARACTERISTICS..................................................... 23

7.1 Modulation.................................................................................................................... 24

7.1.1 E5 Signal..................................................................................................................24

7.1.1.1 Modulation Scheme ..........................................................................................24

7.1.1.2 Modulation Type............................................................................................... 25

7.1.2 E6 Signal..................................................................................................................28


7.1.2.2 Modulation Type............................................................................................... 307.1.3 E1 Signal..................................................................................................................30


7.1.3.2 Modulation Type............................................................................................... 31

7.2 Logic Levels .................................................................................................................. 31

7.3 Transmitted Signal Phase noise .................................................................................. 32

7.4 Transmitted signal code/data coherency.................................................................... 32

7.5 Payload and component reception losses ...................................................................32


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8. GALILEO SPREADING CODES CHARACTERISTICS.................................. 33

8.1 Code Lengths ................................................................................................................ 33

8.2 Spreading codes generation......................................................................................... 33

8.2.1 Spreading codes generation for long codes .............................................................33

8.2.2 Generation of truncated and combined M-sequences for primary codes ................ 34

8.3 Primary Codes.............................................................................................................. 37

8.3.1 E5 Primary Codes.................................................................................................... 37

8.3.1.1 Base register 2 start value for E5a-I..................................................................38

8.3.1.2 Base register 2 start value for E5a-Q ................................................................39

8.3.1.3 Base register 2 start value for E5b-I .................................................................40

8.3.1.4 Base register 2 start value for E5b-Q................................................................41

8.3.2 E1-B and E1-C Primary Codes................................................................................ 41

8.4 Secondary Codes .......................................................................................................... 428.4.1 Definition of secondary codes ................................................................................. 42

8.4.2 Secondary codes assignment ................................................................................... 44

8.5 Code Assignments to Satellites.................................................................................... 45

9. GALILEO MESSAGE STRUCTURE............................................................... 46

9.1 general Message Format Specification.......................................................................46

9.1.1 General Navigation Message Content .....................................................................46

9.1.2 General Navigation Message structure....................................................................46

9.1.2.1 Message Data Frames ....................................................................................... 46

9.1.2.2 Page Structure ................................................................................................... 46

9.1.3 Bit and byte ordering criteria................................................................................... 47

9.1.4 FEC Coding and Interleaving Parameters ...............................................................47

9.1.4.1 FEC encoding and Viterbi decoding.................................................................47

9.1.4.2 Interleaving ....................................................................................................... 48

9.1.5 Page processing sequence at reception....................................................................48

9.1.6 Frame Timing .......................................................................................................... 49

9.2 F/NAV message description......................................................................................... 499.2.1 General description of the F/NAV message............................................................49

9.2.2 F/NAV Page Layout ................................................................................................ 49

9.2.2.1 Tail bits ............................................................................................................. 50

9.2.2.2 F/NAV Word .................................................................................................... 50

9.2.3 F/NAV Frame Layout..............................................................................................50

9.2.4 F/NAV Page Contents .............................................................................................54

9.2.4.1 F/NAV E5a page type 1.................................................................................... 54

9.2.4.2 F/NAV E5a page type 2 and 3 .......................................................................... 54

9.2.4.3 F/NAV E5a page type 4.................................................................................... 55


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9.2.4.4 F/NAV E5a-I Page Type 5 and 6......................................................................55

9.3 I/NAV message description ......................................................................................... 569.3.1 General description of the I/NAV message.............................................................56

9.3.1.1 General Page Layout.........................................................................................56

9.3.1.2 Nominal Sub-Frame Layout ............................................................................. 58

9.3.1.3 Nominal Frame Layout ..................................................................................... 58

9.3.1.4 Page Contents.................................................................................................... 60

10. MESSAGE DATA CONTENTS....................................................................... 65

10.1 Navigation Data......................................................................................................... 65

10.1.1 Ephemeris............................................................................................................. 6510.1.2 Time Correction and Clock Correction Parameters .............................................67

10.1.2.1 Satellite time correction data ............................................................................ 67

10.1.2.2 Galileo System Time (GST) ............................................................................. 68

10.1.2.3 Clock Correction...............................................................................................68

10.1.2.4 Broadcast Group Delay .................................................................................... 69

10.1.2.5 Ionospheric correction ...................................................................................... 71

10.1.2.6 UTC Conversion...............................................................................................72

10.1.2.7 GPS to Galileo System Time............................................................................ 74

10.1.3 Service parameters ...............................................................................................74

10.1.3.1 Satellite ID........................................................................................................ 74

10.1.3.2 Issue Of Data and Reference Time...................................................................7410.1.3.3 Navigation Data Validity and Signal Health Status in F/NAV ........................75

10.1.3.4 Checksum ......................................................................................................... 76

10.1.4 Almanac ............................................................................................................... 77

11. ANNEX 1 RANDOMLY GENERATED CODESP........................................... 270H7988H

11.1 Hexadecimal coding Convention .............................................................................271H

79

89H11.2 Primary codes for the E5a-I signal component ...................................................... 272H81

90H11.3 Primary codes for the E5a-Q signal component .................................................. 273H103

91H11.4 Primary codes for the E5b-I signal component.................................................... 274H125

92H11.5 Primary codes for the E5b-Q signal component .................................................. 275H147

93H

11.6 Primary codes for the E1-B signal component.....................................................276H

169

94H11.7 Primary codes for the E1-C signal component..................................................... 277H181


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Index of Figures

95H

Figure 1: Space Vehicle / Navigation User Interface...............................................................278H

13

96HFigure 2: Galileo Frequency Plan............................................................................................. 279H19

97HFigure 3: Galileo frequency spectrum...................................................................................... 280H21

98H

Figure 4: Modulation scheme for the E5 signal .......................................................................281H

24

99HFigure 5: One period of the two subcarrier functions involved in AltBOC modulation.......... 282H27

100HFigure 6: 8-PSK phase-state diagram of E5 AltBOC signal .................................................... 283H27

101H

Figure 7: Modulation scheme for the E6 signal .......................................................................284H

29

102HFigure 8: Modulation scheme for the E1 signal ....................................................................... 285H30

103HFigure 9: Tiered codes generation............................................................................................ 286H34

104H

Figure 10: Linear shift register based code generator for truncated and..................................287H

35

105HFigure 11: Code register feedback taps representation (example for E5a-I)............................ 288H36

106HFigure 12: Start value representation for Base-register 2......................................................... 289H36

107H

Figure 13: General page layout ................................................................................................290H

46

108HFigure 14: Convolutional coding scheme................................................................................. 291H48

109H

Figure 15: F/NAV Message Structure......................................................................................292H

49

110H

Figure 16: Example for the translation of logical (binary) spreading code into hexadecimal

representation..................................................................................................................... 293H79


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Index of Tables

111H

Table 1: Carrier Frequency per Signal .....................................................................................294H

19

112HTable 2: Galileo signals Rx reference bandwidths.................................................................. 295H20

113HTable 3: Primary Galileo Navigation Signal Parameters ......................................................... 296H22

114H

Table 4: Signal description parameters ....................................................................................297H

23

115HTable 5: E5 chip rates and subcarrier rates .............................................................................. 298H25

116HTable 6: E5 symbol rates .......................................................................................................... 299H25

117H

Table 7: AltBOC subcarrier coefficients..................................................................................300H

26

118HTable 8: Look-up table for AltBOC phase states in dependency of......................................... 301H28

119HTable 9: E6 chip rates and subcarrier rates .............................................................................. 302H29

120H

Table 10: E6 symbol rates ........................................................................................................303H

29

121HTable 11: E1 chip- and subcarrier-rates ................................................................................... 304H31

122HTable 12: E1 symbol rates ........................................................................................................ 305H31

123H

Table 13: Logic to Signal Level Assignment...........................................................................306H

31

124HTable 14: Additional losses due to Rx filtering........................................................................ 307H32

125H

Table 15: Code lengths.............................................................................................................308H

33

126H

Table 16: Primary Codes Specification....................................................................................309H

37

127HTable 17: Base register 2 start values and first code chip for E5a-I......................................... 310H38

128H

Table 18: Base register 2 start values and first code chip for E5a-Q .......................................311H

39

129H

Table 19: Base register 2 start values and first code chip for E5b-I ........................................312H

40

130HTable 20: Base register 2 start values and first code chips for E5b-Q ..................................... 313H41

131H

Table 21: Secondary code sequences (Part 1)..........................................................................314H

43

132H

Table 22: Secondary code sequences (Part 2)..........................................................................315H

44

133HTable 23: Secondary code assignment ..................................................................................... 316H45

134H

Table 24: Message allocation and general data content...........................................................317H

46

135HTable 25: Synchronisation patterns .......................................................................................... 318H47

136HTable 26: Data coding parameters ............................................................................................ 319H47

137H

Table 27: Interleaving parameters............................................................................................320H

48

138HTable 28: F/NAV E5a-I page layout ........................................................................................ 321H50

139HTable 29: F/NAV E5a-I message data packet transmission sequence ..................................... 322H52

140H

Table 30: GST/Sub-frame concordance ...................................................................................323H

54

141HTable 31: Bits allocation for F/NAV E5a-I page type 1 .......................................................... 324H54

142HTable 32: Bits allocation for F/NAV E5a-I page type 2: ephemeris (1/3) with GST .............. 325H54

143H

Table 33: Bits allocation for F/NAV E5a-I page type 3: ephemeris (2/3) with GST ..............326H

55


145H

Table 35: Bits allocation for F/NAV E5a-I page type 5 ..........................................................328H

55


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147H

Table 37: I/NAV nominal page with bits allocation ................................................................330H

57148HTable 38: I/NAV alert page with bits allocation ...................................................................... 331H57

149H

Table 39: I/Nav nominal sub-frame structure ..........................................................................332H

58

150H

Table 40: I/NAV sub-frame sequencing ..................................................................................333H

60

151HTable 41: Bits allocation for word type 1................................................................................. 334H60

152H

Table 42: Bits allocation for word type 2.................................................................................335H

60

153H


60


155H


61

156HTable 46: Bits allocation for word type 6................................................................................. 339H61157HTable 47: Bits allocation for word type 7................................................................................. 340H62

158H


62


160H

Table 50: Bits allocation for word type 10...............................................................................343H

63

161HTable 51: I/NAV dummy message with bits allocation ........................................................... 344H63

162HTable 52: Dummy word with bits allocation............................................................................ 345H64

163H

Table 53: Ephemeris parameters ..............................................................................................346H

66

164HTable 54: GST parameters........................................................................................................ 347H68

165HTable 55: Galileo clock correction parameters ........................................................................ 348H68

166H

Table 56: Galileo clock correction data within F-NAV navigation message ..........................349H

69

167HTable 57: BGD parameters....................................................................................................... 350H69

168H

Table 58: BGD values mapping on messages and services .....................................................351H

70

169H

Table 59: Ionospheric correction parameters ...........................................................................352H

71

170HTable 60: Parameters for the GST - UTC conversion.............................................................. 353H73

171H

Table 61: Parameters for the GPS time conversion .................................................................354H

74

172H

Table 62: Satellite ID ...............................................................................................................355H

74

173HTable 63: IOD values mapping on data type............................................................................ 356H75

174H

Table 64: Data validity satellite status (transmitted on E5a) ...................................................357H

75

175HTable 65: Data validity satellite status (transmitted on E5b and E1-B) ................................... 358H76

176HTable 66: Data validity status bit values .................................................................................. 359H76

177H

Table 67: Signal health status for E5a (transmitted on E5a) ....................................................360H

76

178HTable 68: Signal health status bit values .................................................................................. 361H76

179HTable 69: Almanac parameters................................................................................................. 362H78

180H

Table 70: Primary code-length and hexadecimal representation characteristics for the different

Galileo signal components................................................................................................. 363H80


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1. SCOPE

The present Galileo Signal In Space Interface Control Document (SIS ICD)

Draft 0 contains the publicly available information on the Galileo Signal In

Space.

The present document is subject to evolution, and the information

contained in it may change.

It is recommended that a reconfigurable approach for the Galileo receivers be

adopted by the manufacturers, in order to easily adapt the receivers' architectureto the possible changes which might occur in the future.


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2. INTRODUCTION

Galileo is the European global navigation satellite system, providing a highly accurate,

guaranteed global positioning service under civilian control. It is inter-operable with GPS and

GLONASS, the two other global satellite navigation systems.

The fully deployed Galileo system consists of 30 satellites (27 operational + 3 spares),

positioned in three circular Medium Earth Orbit (MEO) planes at a nominal average orbit

semi-major axis of 29601.297 Km, and at an inclination of the orbital planes of 56 degrees

with reference to the equatorial plane. Once this is achieved, the Galileo navigation signals

provide a good coverage even at latitudes up to 75 degrees north and 75 degrees south.

Galileo provides enhanced distress localisation and call features for the provision of a Search

and Rescue service interoperable with the COSPAS-SARSAT system.

This Galileo Signal-In-Space Interface Control Document is intended for use by the Galileouser community. It specifies the interface between the Galileo Space Segment, and the Galileo

User Segment.

364H

Figure 1 specifies the RF air interface between the space and user segment. Three

independently usable signals are permanently transmitted by all Galileo satellites: E5, E6 and

E1. The E5 link is further sub-divided into two RF links denoted E5a and E5b.

Figure 1: Space Vehicle / Navigation User Interface

This document describes the signals related to the open service of Galileo with the intention to

foster its standardization for mass-market development.

GALILEO SPACE SEGMENT (SS)

GALILEO SPACEVEHICLE (SV)

GALILEO USERSEGMENT (US)

E5 E6 E1

E5a E5b E6 E1


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3. LIST OF ACRONYMS

AltBOCConstant envelope modulation scheme for combining two sidebands each

consisting itself of two binary signals (in I- and Q-channel).

AltBOC(n,m)AltBOC with chipping rate m*1.023 Mcps and a sub-carrier frequency of

n*1.023 MHz.

ARNS Aeronautical Radio Navigation Services

BGD Broadcast Group Delay

BOC Binary Offset Coding with sine shaped subcarrier (see Definitions)

BOC(n,m)Binary Offset Carrier signal with chipping rate of m*1.023 Mcps and a

sub-carrier frequency of n*1.023 MHz

BOCc Binary Offset Coding with cosine shaped subcarrier (see Definitions) bps Bits per second

BPSK Binary Phase Shift Keying

BPSK(m) Binary Phase Shift Keying with chipping rate of m*1.023 Mcps

CCF Cross-Correlation Function

CDMA Code Division Multiple Access

CL Correlation Loss

CoM Centre of Mass

CoP Centre of Phase

COSPAS-SARSAT

Cosmicheskaya Systyema Poiska Avariynich Sudov - Search and RescueSatellite Aided Tracking

CRC Cyclic Redundancy Check

CS Commercial Service

DME Distance Measurement Equipment

EC European Commission

EIRP Equivalent Isotropic Radiated Power

ESA European Space Agency

FEC Forward Error Correction

GGTO Galileo/GPS Time Offset

GJU Galileo Joint Undertaking

GMS Ground Mission Segment

GPS Global Positioning System

GSS Ground Sensor Station

GST Galileo System Time

HPA High Power Amplifier

I In-Phase Component

ICD Interface Control Document

ID Identification


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IF Integrity Flag

IOD Issue Of DataITU International Telecommunication Union

JTIDS Joint Tactical Information Distribution System

LAN Longitude of the Ascending Node

LFSR Linear Feedback Shift Register

LSB Least Significant Bit

Mcps Mega chips per second

MHz Megahertz

MIDS Multifunctional Information Distribution System

MSB Most Significant BitMSS Mobile Satellite Service

N/A Not Applicable

NIB Non Interference Basis

NP Non-Periodic

ODTS Orbit Determination and Time Synchronisation

OS Open Service

PRN Pseudo-Random Noise

Q Quadrature Component

QPSK(m) Quadrature Phase Shift Keying with chipping rate of m*1.023 Mcps

RF Radio Frequency

RHCP Right-Hand Circular Polarization

RLM Return Link Message

RNSS Radio Navigation Satellite System

RX Receiver

SAR Search-and-Rescue Service/Signal

SIS Signal-In-Space

SISA Signal In Space Accuracy

SISE Signal In Space Error

SNF Satellite Navigation Frame

SoL Safety-of-Life Service

Sps Symbols per second

SS Space Segment

SV Space Vehicle

SVID Space Vehicle IDentificator

TACAN Tactical Air Navigation

TBC To Be Confirmed


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TBD To Be Decided

TOC Time Of ComputationTOT Time Of Transmission

TOW Time Of Week

TTF Time To Fix

ULS Up-Link Station

UMRP User Minimum Received Power

US User Segment

UTC Universal Time Coordinated

WN Week Number


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4. DEFINITIONS AND NOMENCLATURE IN THIS DOCUMENT

E5-Signal The Galileo E5-signal consists of the signals E5a, E5b (and modulation

product signals) and is transmitted in the frequency band 1164 1215

MHz allocated to RNSS with a worldwide co-primary status. The E5-

signal shares the band with the co-primary Aeronautical Radionavigation

Service (ARNS) (ITU-R Radio Regulations). Moreover, it shares the

band with other RNSS-signals provided by EGNOS, GPS-L5,

GLONASS etc. as well as signals of the ARNS (DME, TACAN). Also

found in the band is the JTIDS-MIDS signal which is permitted on an

NIB.

E5a-Signal The Galileo E5a-signal is an inherent element of the E5-signal and

consists of a data-channel transmitted in the in-phase component and a pilot-channel transmitted in the quadrature component. The E5a-signal

provides the F/NAV message supporting Galileo Open Service and

overlaps (in the spectrum) with the GPS-L5-signal.

E5b-Signal The Galileo E5b-signal is an inherent element of the E5-signal and

consists of a data-channel transmitted in the in-phase component and a

pilot-channel transmitted in the quadrature component. The E5b-signal

provides the I/NAV message and supports Safety of Life service, Galileo

system integrity and Open Service.

E6-Signal The Galileo E6-signal consists of the signal components E6-B and E6-C

and is transmitted in the frequency band 1215 - 1300 MHz allocated on a

worldwide co-primary basis (ITU-R Radio Regulations), sharing with

radar systems of the radio navigation and radiolocation service. The

signal components E6-B and E6-C are data-channel and pilot-channel

respectively. The E6-signal provides the C-NAV message and supports

Commercial Service.

E1- Signal The Galileo E1-signal comprises the signal components E1-B and E1-C

and is transmitted in the frequency band 1559 - 1610 MHz allocated to

RNSS and ARNS on a worldwide co-primary basis (ITU-R Radio

Regulations).

The signal components E1-B and E1-C are data-channel and pilot-

channel respectively. The E1-signal provides the I/NAV message andsupports Safety of Life service, Galileo system integrity and Open

Service.

Navigation Data

Stream

Sequence of bits carrying the navigation data information by using a

frame structured transmission protocol.

F/NAV Message Freely accessible navigation message provided by the E5a signal for

Open Service.

I/NAV Message Integrity navigation message type provided by E5b and E1-B signals,

supporting Safety of Life Service and providing extended system

integrity information.

C/NAV Message Commercial navigation message type provided by the E6-B signal


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supporting Commercial Service.

Data channel A data channel is the result of modulating ranging code, sub-carrier (ifpresent) and secondary code with a navigation data stream.

Pilot channel A pilot channel (or dataless channel) is made of ranging code, sub-carrier

(if present) and secondary code only, not modulated by a navigation data

stream.

Receiver

reference

bandwidth

The bandwidth of a hypothetical receiver with ideal (rectangular

frequency response) input filters.

BOC(fBsubB,fBchipB) Binary Offset Carrier modulation, with subcarrier frequency fBsubB and chip

rate fBchipB, where frequencies are indicated as multiples of 1.023 MHz. For

example, a BOC(10,5) signal has a subcarrier frequency of 10x1.023MHz=10.230 MHz and a code chip rate of 5x1.023MHz=5.115 MHz.

Unless specified otherwise, the subcarrier-function of code-chips is

sign[sin(2*pi*fBsubB*t)], with sub-carrier frequency fBsubB and code-chips

starting at t=0

BOCc(fBsubB,fBchipB) Binary Offset Carrier modulation-cosine. It is defined as above, but with

the subcarrier-function of code-chips according to sign[cos(2*pi*fBsubB*t)],

with sub-carrier frequency fBsubB and code-chips starting at t=0.


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5. GALILEO FREQUENCY PLAN

5.1 FREQUENCY BANDS

The Galileo Navigation Signals are transmitted in the four frequency bands indicated in blue

in 365HFigure 2. These four frequency bands are: the E5a band, the E5b band, the E6 band and the

L1 band. They provide a wide bandwidth for the transmission of the Galileo Signals.

RNSS Bands RNSS Bands

ARNS Bands ARNS Bands

SARE5a/L5 E5b E6 L1

1164MHz

1260

MHz

1300

MHz

1176

.45MHz

1278

.75

MHz

1544

MHz

1545

MHz

1559

MHz

1591

MHz

1575

.42

MHz

1215

MHz

1237

MHz

L2

1207

.140

MHz

Galileo Bands (Navigation) Galileo SAR Downlink GPS Bands

1191

.795

MHz

1227

MHz

RNSS Bands RNSS Bands

ARNS Bands ARNS Bands

SARE5a/L5 E5b E6 L1

1164MHz

1260

MHz

1300

MHz

1176

.45MHz

1278

.75

MHz

1544

MHz

1545

MHz

1559

MHz

1591

MHz

1575

.42

MHz

1215

MHz

1237

MHz

L2

1207

.140

MHz

Galileo Bands (Navigation) Galileo SAR Downlink GPS BandsGPS Bands

1191

.795

MHz

1227

MHz

Figure 2: Galileo Frequency Plan

The frequency bands have been selected in the allocated spectrum for Radio Navigation

Satellite Services (RNSS) and in addition to that, E5a, E5b and L1 bands are included in the

allocated spectrum for Aeronautical Radio Navigation Services (ARNS), employed by Civil-

Aviation users, and allowing dedicated safety-critical applications.

5.2 CARRIER FREQUENCIES AND BANDWIDTHS

Galileo carrier frequencies are shown in 366HTable 1. The beginning and ending frequencies of

each band are reported in367H

Figure 2.

Signal Carrier FrequencyE5a 1176.450 MHz

E5b 1207.140 MHz

E5 (E5a+E5b) 1191.795 MHz

E6 1278.750 MHz

E1 1575.420 MHz

Table 1: Carrier Frequency per Signal

The Rx reference bandwidths and polarisations are specified in368H

Table 2.


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Signal Rx Reference Bandwidth Polarisation

E5 51.150 MHz RHCP

E6 40.920 MHz RHCP

E1 24.552 MHz RHCP

Table 2: Galileo signals Rx reference bandwidths

5.3 MULTIPLE ACCESS

All Galileo transmitting satellites share the same frequency bands, making use of Code

Division Multiple Access (CDMA) technique. Spread Spectrum signals are transmitted

including different ranging codes per signal component, per signal, per frequency and perGalileo satellites.


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6. GALILEO SIGNALS AND MAPPING TO SERVICES

369H

Figure 3 illustrates the baseline Galileo signals spectral characteristics as well as modulation,

chip rate, and data rate.

Figure 3: Galileo frequency spectrum

Each Galileo satellite transmits navigation signals denoted as E1, E6, E5a and E5b signals.

UE1 signalU: E1 is an open access signal transmitted in the L1 band comprising a datachannel E1-B and a pilot (or dataless) channel E1-C. It has unencrypted ranging codes

and navigation data, accessible to all users. The E1-B data stream also contains

unencrypted integrity messages and encrypted commercial data. The E1-B data rate is

125 bps. The E1 signal supports the OS, CS, and the SoL service

UE6 signal U: E6 is a commercial access signal transmitted in the E6 band that includes adata channel E6-B and a pilot (or dataless) channel E6-C. Its ranging codes and data

are encrypted. A data rate of 500 bps allows the transmission of added-value

commercial data. The E6 signal is a dedicated signal for supporting the CS

UE5a signalU: E5a is an open access signal transmitted in the E5 band that includes adata channel and a pilot (or dataless) channel. The E5a signal has unencrypted ranging

codes and navigation data, which are accessible by all users. It transmits the basic data

to support navigation and timing functions, using a relatively low 25 bps data rate that

enables more robust data demodulation. The E5a signal supports the OS

UE5b signal U: E5b is an open access signal transmitted in the E5 band that includes adata channel and a pilot (or dataless) channel. It has unencrypted ranging codes and

navigation data accessible to all users. The E5b data stream also contains unencrypted

integrity messages and encrypted commercial data. The data rate is 125 bps. The E5b

signal supports the OS, CS and SoL service

40x1.023 MHz

E6 Signal:

Data + Pilot

BPSK mod.

Rc=5.115 Mcps

Rs=1000 sps

CS Service

24x1.023 MHz

E1Signal:Data+ PilotBOC(1,1) mod.

Rc=1.023 McpsRs=250 spsOS/CS/SoLServices

E5a Signal:Data+PilotBPSK mod.Rc=10.23 McpsRs=50 spsOS/CSServices

E5b Signal:

Data+PilotBPSK mod.Rc=10.23 McpsRs=250 spsOS/CS/SoLServices

Frequency

(MHz)

50x1.023 MHz

E5 Signal:

AltBOC(15,10) mod.

1191.795 MHz1278.75 MHz

1575.42 MHz

Spectral componentnon discussed in this

SIS ICD

Spectral componentnon discussed in this

SIS ICD


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The E5a and E5b signals are modulated onto a single E5 carrier using a technique known as

AltBOC. The composite of the E5a and E5b signals is denoted as the E5 signal and can be processed as a single large bandwidth signal with an appropriate user receiver

implementation. Power sharing between pilot and data channels of each carrier is always

50%.

370HTable 3 is a summary of the primary Galileo navigation signal parameters.

Signal name ChannelModulation

Type

Chip Rate

[Mcps]

Symbol Rate

[sps]

User min. received power

above 10 elevation [dBW]

(based on an ideally

matched and isotropic 0

dBi antenna and lossless

atmosphere)

E5a data 50

E5a pilot N/A-155

E5b data 250E5

E5b pilot

AltBOC(15,10) 10.23

N/A-155

E6-B data 1000E6

E6-C pilotBPSK(5) 5.115

N/A-155

E1-B data 250E1

E1-C pilotBOC(1,1) 1.023

N/A-157

Table 3: Primary Galileo Navigation Signal Parameters

The Galileo terrestrial users maximum received signal power level is, using the same

assumptions as for the minimum received power, not expected to exceed 3 dB above the

corresponding minimum received power.

For purposes of establishing user receiver dynamic range for receiver design and test, the

maximum received signal power level is not expected to exceed 7 dB above the

corresponding minimum received power.


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7. GALILEO SIGNALS CHARACTERISTICS

The Galileo Signal in Space (SIS) comprises signals modulated onto three separate carriers:

The E5-, E6- and E1-Signal.

The following371H

Table 4 defines the signal parameters used in this chapter, with the indices:

X accounting for the respective carrier (E5, E5a, E5b, E6 or E1) and

Y accounting for the respective signal component or signal channel (B, C, I or Q)within the signal X.

Parameter Explanation Unit

fB

XB

Carrier frequency HzP

BXB RF-Signal power W

LBX-YB Ranging code repetition period chips

TBC,X-YB Ranging code chip length s

TBS,X-YB Subcarrier period s

TBD,X-YB Navigation message s UymbolU duration s

RBC,X-YB = 1/ T BC,X-YB; code chip rate Hz

RBS,X-YB = 1/ T BS,X-YB; Subcarrier frequency Hz

RBD,X-YB = 1/ T BD,X-YB; Navigation message symbol rate Hz

SBXB(t) Signal pass-band representation

CBX-YB(t) Binary (NRZ modulated) ranging code

DBX-YB(t) Binary (NRZ modulated) navigation message signal

scBX-YB(t) Binary (NRZ modulated) subcarrier

e BX-YB(t) Binary NRZ modulated navigation signal component

including code, sub-carrier (if available) and navigation

message data (if available); ( = CBX-YB(t) scBX-YB(t) DBX-YB(t)

);

sBXB(t) Normalised baseband signal (=sBX-IB(t) + j sBX-QB(t)) (unit

mean power)c BX-Y,kB kP

thP Chip of the ranging code

dBX-Y,kB kP

thP Symbol of the navigation message

DCBX-YB = TBD,XPB

YP/

P

PT

BC,XPBY

P; number of code chips per symbol

|i| BLB i modulo L

[i]BDCB Integer part of i/DC

rectBTB(t) Function rectangle, which is equal to 1 for 0


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7.1 MODULATION

In the following sections, modulation expressions are given for the power normalizedcomplex envelope (i.e. base-band version) s(t) of a modulated (band-pass) signal S(t). Both

are described in terms of its in-phase and quadrature components by the following generic

expressions in372H

Eq. 1:

( ) ( ) ( ) ( )[ ])()()(

,2sin)2cos(2

tsjtsts

tftstftsPtS

QXIXX

XQXXIXXX

+=

=

Eq. 1

with the parameters according to373H

Table 4.

7.1.1 E5 Signal

7.1.1.1Modulation SchemeThe diagram in 374HFigure 4 provides a generic view of the E5 signal modulation.

AltBOC

CE5a-I(t)

sE5(t)

CE5a-Q(t)

CE5b-I(t)

CE5b-Q(t)

DE5a-I (t)

DE5b-I (t)

AltBOCAltBOC

CE5a-I(t)

sE5(t)

F/NAV:

I/NAV:

CE5a-Q(t)

CE5b-I(t)

CE5b-Q(t)

DE5a-I (t)

DE5b-I (t)

Figure 4: Modulation scheme for the E5 signal

The E5 signal components are generated according to the following:

eBE5a-IB from the F/NAV navigation data stream D BE5a-IB modulated with the unencryptedranging code C

BE5a-IB

eBE5a-QB (pilot channel) from the unencrypted ranging code C BE5a-QB

eBE5b-IB from the I/NAV navigation data stream D BE5b-IB modulated with the unencryptedranging code CBE5b-I B

eBE5b-QB (pilot channel) from the unencrypted ranging code C BE5b-QB

The respective definitions are following (375H

Eq. 2):


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[ ] ( )

( )

[ ] ( )

( )

+

=

+

=

+

=

+

=

=

=

=

=

iQbECTiQbEQbE

iIbECTiIbEiIbEIbE

iQaECTiQaEQaE

i

IaECTiIaEiIaEIaE

Titrectcte

Titrectdcte

Titrectcte

Titrectdcte

QbECQbEL

IbECIbEDCIbEL

QaEcQaEL

IaECIaEDCIaEL

5,,55

5,,5,55

5,,55

5,,5,55

5,5

5,55

5,5

5,55

)(

)(

)(

)(

Eq. 2

The Galileo satellites transmit ranging codes for E5 signal components with the chip- and

subcarrier- rates stated in the following 376HTable 5.

Signal

(Parameter X)

Channel

(Parameter Y)

Subcarrier-rate

RBS,X-YB [MHz]

Ranging code chip-rate

RBC,X-YB [MChip/s]

I No subcarrier 10.230E5a

Q No subcarrier 10.230

I No subcarrier 10.230E5b

Q No subcarrier 10.230

Table 5: E5 chip rates and subcarrier rates

The Navigation Data Message streams after channel encoding are transmitted for E5 signal

components with the symbol rates as stated in the following 377HTable 6.

Signal

(Parameter X)

Channel

(Parameter Y)

Symbol-rate

RBD,X-YB [symbols/s]

I 50E5a

Q No data (pilot channel)

I 250E5b

Q No data (pilot channel)

Table 6: E5 symbol rates

7.1.1.2Modulation TypeThe wideband E5 signal is generated with the AltBOC modulation of side-band sub-carrier

rate RBS,E5 B = 1/TBS,E5 B = 15.345 MHz (15 x 1.023 MHz) according to the expression in 378HEq. 3:


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( ) ( ) ( )( ) ( ) ( )[ ]

( ) ( )( ) ( ) ( )[ ]

( ) ( )( ) ( ) ( )[ ]

( ) ( )( ) ( ) ( )[ ] .4Ttscjtsctejte22

1

4Ttscjtsctejte22

1

4Ttscjtsctejte22

1

4Ttscjtsctejte

22

1ts

5E,sP5EP5EQb5EIb5E

5E,sP5EP5EQa5EIa5E

5E,sS5ES5EQb5EIb5E

5E,sS5ES5EQa5EIa5E5E

++

++

+++

++

=

Eq. 3

with the binary signal components eBE5a-IB, eBE5a-QB, eBE5b-IB and eBE5b-QB (consisting of the BPSK

modulated ranging codes multiplied with the respective navigation data stream for the data-

channels) as defined in379H

Eq. 2. The respective dashed signal components BE5a-IB, BE5a-QB, BE5b-IB and

BE5b-Q B represent product signals according to 380HEq. 4:

.eeee,eeee

,eeee,eeee

Qa5EIa5EIb5EQb5EQb5EIb5EIa5EQa5E

Qa5EIa5EQb5EIb5EQb5EIb5EQa5EIa5E

==

==

Eq. 4

The parameters sc BE5-S B and scBE5-PB represent the four valued sub-carrier functions for the single

signals and the product signals respectively:

( ) ( )

==

i EsTiSETitrectAStsc

ES

85,8/5 5,8

and

( ) ( )

= =

iEsTiPE

TitrectAPtscES

85,8/5 5,8

Eq. 5

with the coefficients ASBiB and APBiB according to the following 381HTable 7.

i 0 1 2 3 4 5 6 7

2 ASBiB 12 + 1 -1 12 12 -1 1 12 +

2 APBiB 12 + 1 -1 12 12 -1 1 12 +

Table 7: AltBOC subcarrier coefficients

One period of the subcarrier functions sc BE5-S B and scBE5-PB is shown in the following 382HFigure 5.


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Figure 5: One period of the two subcarrier functions involved in AltBOC modulation

The relative power of the product-signals within the unfiltered base-band signal sBE5B(t) is

( ) %158112 2

+ .

Equivalently, the AltBOC complex baseband signal sBE5B(t) can be described as an 8-PSK

signal,

( ) ( ) ( ) { },8,7,6,5,4,3,2,1with4

exp5

= tktkjtsE

Eq. 6

and the corresponding phase states illustrated in the following 383HFigure 6.

I

Q

1

2

7

3

4

5

6

8

Figure 6: 8-PSK phase-state diagram of E5 AltBOC signal

0 1t / TS,E5

( )212+

( )212+

( )212( )212

21

1

21

1

0

AltBOC scE5-s(t)

-

AltBOC scE5-p(t)


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The relation of the 8 phase states to the 16 different possible states for the quadruple eB

E5a-IB

(t),e BE5a-QB(t), e BE5b-I B(t), and eBE5b-QB(t) depends also on time. Therefore, time is partitioned first in sub-

carrier intervals TBs,E5B and further sub-divided in 8 equal sub-periods. The index i BTsB of the

actual sub-period is given by:

( ) { }7,6,5,4,3,2,1,0iwithTmodulotT

8partintegeri Ts5E,s

5E,sTs

= Eq. 7

and determines which relation between input quadruple and phase states has to be used.

The dependency of phase-states from input-quadruples and time is given in the following

384HTable 8.

Input Quadruples

eBE5a-IB -1 -1 -1 -1 -1 -1 -1 -1 1 1 1 1 1 1 1 1

eBE5b-IB -1 -1 -1 -1 1 1 1 1 -1 -1 -1 -1 1 1 1 1

eBE5a-QB -1 -1 1 1 -1 -1 1 1 -1 -1 1 1 -1 -1 1 1

eBE5b-QB -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1

t = t modulo T Bs,E5B

iBTsB tk (according to ( ) ( )4jkexpts 5E = )

0 [0,TBs,E5B/8[ 5 4 4 3 6 3 1 2 6 5 7 2 7 8 8 1

1 [TBs,E5B/8, 2 TBs,E5B/8[ 5 4 8 3 2 3 1 2 6 5 7 6 7 4 8 1

2 [2 TBs,E5B/8, 3 TBs,E5B/8[ 1 4 8 7 2 3 1 2 6 5 7 6 3 4 8 5

3 [3 TBs,E5B/8, 4 TBs,E5B/8[ 1 8 8 7 2 3 1 6 2 5 7 6 3 4 4 5

4 [4 TBs,E5B/8, 5 TBs,E5B/8[ 1 8 8 7 2 7 5 6 2 1 3 6 3 4 4 5

5 [5 TBs,E5B/8, 6 TBs,E5B/8[ 1 8 4 7 6 7 5 6 2 1 3 2 3 8 4 5

6 [6 TBs,E5B/8, 7 TBs,E5B/8[ 5 8 4 3 6 7 5 6 2 1 3 2 7 8 4 1

7 [7 TBs,E5B/8, TBs,E5B [ 5 4 4 3 6 7 5 2 6 1 3 2 7 8 8 1

Table 8: Look-up table for AltBOC phase states in dependency of

input quadruples and time

7.1.2 E6 Signal

7.1.2.1Modulation SchemeThe diagram in the following 385HFigure 7 provides a generic view of the E6 signal generation.


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( )tCBE 6

( )tDBE 6

( )tCCE 6

( )tsE6

( )teBE 6

( )teCE 6

2

1


The E6 signal components are generated according to the following:

eBE6-BB from the C/NAV navigation data stream D BE6-BB modulated with the ranging codeCBE6-BB. Note: C/NAV message format is not subject of this ICD for Galileo OS.

eBE6-CB (pilot channel) from the ranging code C BE6-C B

The B and C components are generated according to the following 386HEq. 8

[ ] ( )

( )

+

=

+

=

=

=

iCECTiCECE

iBECTiBEiBEBE

Titrectcte

Titrectdcte

CECCEL

BECBEDCBEL

6,,66

6,,6,66

6,6

6,66

)(

)(

Eq. 8

Galileo satellites transmit ranging codes for E6 signal components with the chip rates stated in387H

Table 9. For signal components with additional sub-carrier modulation, also the sub-carrier

rates are stated in 388HTable 9.

Channel

(Parameter Y)

Subcarrier type Subcarrier rate

RBS,E6-YB [MHz]

Ranging code chip-rate

RBC,E6-YB [MChip/s]

B No subcarrier - 5.115

C No subcarrier - 5.115

Table 9: E6 chip rates and subcarrier rates


components with the symbol rates as stated in389H

Table 10.

Channel

(Parameter Y)

Symbol-rate

RBD,E6-YB [symbols/s]

B 1000

C No data (pilot channel)



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7.1.2.2Modulation TypeThe E6 signal is generated according to 390HEq. 9, with the binary signal components e BE6-BB(t) ande

BE6-CB(t).

Note that both pilot and data channel are combined on the same carrier component.

( ) ( ) ( )[ ]tetetsCEBEE = 666

2

1 Eq. 9

7.1.3 E1 Signal

7.1.3.1Modulation SchemeThe diagram in 391HFigure 8 provides a generic view of the E1 signal generation.

( )tCBE1

( )tDBE1

( )tC

CE1

( )tsE1

( )teBE1

( )te CE1

( )tscCE1

( )tscCE1

2

1


The E1 signal components are generated according to the following.

eBE1-BB from the I/NAV navigation data stream D BE1-B B, modulated with the ranging codeC

BE1-BB and the sub-carrier sc BE1-B B

eBE1-CB (pilot channel) from the ranging code C BE1-C B modulated with the sub-carrier sc BE1-C B

The B and C components are generated according to the following 392HEq. 10:

[ ] ( ) ( )[ ][ ]

( ) ( )[ ][ ]

+

=

+

=

=

=

i

CESCECTiCECE

i

BESBECTiBEiBEBE

tRTitrectcte

tRTitrectdcte

CECCEL

BECBEDCBEL

1,1,,11

1,1,,1,11

2sinsign)(

2sinsign)(

1,1

1,11

Eq. 10

Galileo satellites transmit ranging codes for E1 signal with the chip- and subcarrier- rates

stated in 393HTable 11.


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Channel(Parameter Y)

Subcarriertype

Subcarrier-rateR

BS,E1-YB [MHz]Ranging code chip-rate

RBC,E1-YB [MChip/s]

B BOC 1.023 1.023

C BOC 1.023 1.023

Table 11: E1 chip- and subcarrier-rates


components with the symbol rates as stated in 394HTable 12.

Channel

(Parameter Y)

Symbol-rate

RBD,E1-YB [symbols/s]

B 250

C No data (pilot channel)


7.1.3.2Modulation TypeThe E1 composite signal is generated according to 395HEq. 11, with the binary signal components

eBE1-BB(t) and e BE1-CB(t).

( ) ( ) ( )[ ]tetets CEBEE = 1112

1 Eq. 11

Note that as for E6, both pilot and data channel are modulated onto the same carrier

component.

7.2 LOGIC LEVELS

The correspondence between the logic level code bits used to modulate the signal and thesignal level is according to the values stated in

396H

Table 13.

Logic Level Signal Level

1 -1.0

0 +1.0

Table 13: Logic to Signal Level Assignment


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7.3 TRANSMITTED SIGNAL PHASE NOISE

The phase noise spectral density of the un-modulated carrier must allow a second-orderphased locked loop with 10 Hz one-sided noise bandwidth to track the carrier to an accuracy

of 0.04 radians RMS.

7.4 TRANSMITTED SIGNAL CODE/DATA COHERENCY

The edge of each data symbol coincides with the edge of a code chip. Periodic spreading

codes start coincides with the start of a data symbol.

7.5 PAYLOAD AND COMPONENT RECEPTION LOSSES

The correlation loss due to payload distortions will be below 0.6 dB. For the ideal receiver

bandwidth definition as for in 397HTable 2, additional losses due to receiver filtering are to be

considered, as shown in398H

Table 14.

Signal E5 E6 E1

Loss (dB) 0.4 0.0 0.1

Table 14: Additional losses due to Rx filtering


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8. GALILEO SPREADING CODES CHARACTERISTICS

8.1 CODE LENGTHS

The ranging codes are built from so-called primary and secondary codes, by using a tiered

codes construction.

The code length to be used for each signal component is the value stated in399H

Table 14.

Channel Code length (chips)Code Length

(ms) Primary Secondary

E5a-I 20 10230 20

E5a-Q 100 10230 100

E5b-I 4 10230 4

E5b-Q 100 10230 100

E1-B 4 4092 -

E1-C 100 4092 25

Table 15: Code lengths

8.2 SPREADING CODES GENERATION

The primary spreading codes can be either:

linear feedback shift register-based pseudo-noise sequences, or

optimized pseudo-noise sequences.

Optimized codes need to be stored in memory and therefore are often called memory codes.

Register based codes used in Galileo are generated as combinations of two M-sequences,

being truncated to the appropriate length. These codes can be generated either with pairs of

Linear Feedback Shift Registers (LFSR) or might be also stored in memory.

8.2.1 Spreading codes generation for long codes

Long spreading codes are generated by a tiered code construction, whereby a secondary code

sequence is used to modify successive repetitions of a primary code, as shown in 400HFigure 9.

The first chip of the secondary code in binary ('logical level') representation is used to control

the polarity of the first epoch of the primary code sequence by Exclusive OR combination.


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Figure 9: Tiered codes generation

8.2.2 Generation of truncated and combined M-sequences for primary codes

401HFigure 10 shows an example standard implementation of the LFSR method for generation of

truncated and combined M sequences.

For truncation to primary code-length N, the content of the two shift registers is reinitialised

(reset) after N cycles (Primary code Epoch) of the registers with so-called start-values js

(=[sBjPB1

P,,sBjPBR

P]).


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8.3 PRIMARY CODES

8.3.1 E5 Primary Codes

E5 primary codes either can be considered as memory stored binary sequences or can be

generated with LFSR.

In case of memory codes, the E5a-I, E5a-Q, E5b-I and E5b-Q primary codes are according to

the representation provided in Annex 1.

In case of generation via LFSR, the E5a-I, E5a-Q, E5b-I and E5b-Q primary codes use the

principle defined in Par.407H8.2.2, using the parameters defined in 408HTable 15.

Base register polynomial (octal)Signal

component

Length of shift register

(polynomial order) 1 2

E5a-I 14 40503 50661

E5a-Q 14 40503 50661

E5b-I 14 64021 51445

E5b-Q 14 64021 43143

Table 16: Primary Codes Specification

Two parallel registers (as defined in409H

Figure 10) are used: base register 1 and base register 2.The primary output sequence is the exclusive OR of register 1 and 2 outputs; the shift

between the two sequences is zero.

The start values for all base register 1 cells, in logic level notation, are '1' for all codes E5a-I,

E5a-Q, E5b-I and E5b-Q.


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8.3.1.1Base register 2 start value for E5a-IThe octal format base register 2 start value with the convention defined in Par. 410H8.2.2 is as

defined in the following 411HTable 16 for each primary code.

The hexadecimal format of the first 24 code-chips is also given in the table with the following

convention. The n-th group (n = 1, , 6) of four consecutive code-chips in time c 4n-3,..c4n (in

logic level notation) translates into the n-th hexadecimal symbol from the left, representing

the decimal number 8c4n-3 + 4c4n-2 + 2c4n-1 + c4n.

Code

No

Start

Value

Initial

Sequence

Code

No

Start

Value

Initial

Sequence1 30305 3CEA9D 26 14401 9BFAC7

2 14234 9D8CF1 27 34727 18A25B

3 27213 45D1C8 28 22627 69A39F

4 20577 7A0133 29 30623 39B27D

5 23312 64D423 30 27256 454598

6 33463 23300D 31 01520 F2BC62

7 15614 91CEF2 32 14211 9DDBC6

8 12537 AA82DC 33 31465 332827

9 01527 F2A17D 34 22164 6E2FCA

10 30236 3D84AE 35 33516 22C6D511 27344 446D38 36 02737 E881D9

12 07272 C514F2 37 21316 74C4DB

13 36377 0C0184 38 35425 13AB03

14 17046 8767E0 39 35633 119323

15 06434 CB8EFF 40 24655 594886

16 15405 93EBCD 41 14054 9F4D89

17 24252 5D55CE 42 27027 47A3C0

18 11631 B19B7C 43 06604 C9ED53

19 24776 5805FC 44 31455 334994

20 00630 F99EA1 45 34465 1B2A3021 11560 B23CE5 46 25273 5513F3

22 17272 8515E8 47 20763 7831C1

23 27445 436822 48 31721 30B93A

24 31702 30F77B 49 17312 84D5B4

25 13012 A7D629 50 13277 A5029C

Table 17: Base register 2 start values and first code chip for E5a-I


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8.3.1.2Base register 2 start value for E5a-QThe octal format base register 2 start value with the convention defined in Par.

412H

8.3.1.1 is asdefined in the following 413HTable 17 for each primary code number (1-50).

The hexadecimal format of the first 24 code-chips with the convention defined in Par.414H

8.3.1.1

is also given in 415HTable 17.

Code

No

Start

Value

Initial

Sequence

Code

No

Start

Value

Initial

Sequence

1 25652 515537 26 20606 79E450

2 05142 D67539 27 11162 B63460

3 24723 58B2E5 28 22252 6D562B

4 31751 305914 29 30533 3A9010

5 27366 442710 30 24614 59CD72

6 24660 593CF8 31 07767 C0211A

7 33655 214AD7 32 32705 28EB96

8 27450 435EA6 33 05052 D7554B

9 07626 C1A7D5 34 27553 425126

10 01705 F0E94A 35 03711 E0DAFB

11 12717 A8C239 36 02041 EF79F2

12 32122 2EB63B 37 34775 18085D

13 16075 8F0A46 38 05274 D50CD8

14 16644 896DD4 39 37356 0447B9

15 37556 0245F1 40 16205 8DE877

16 02477 EB0160 41 36270 0D1FA0

17 02265 ED28B3 42 06600 C9FCF7

18 06430 CB9F5B 43 26773 48116D

19 25046 576592 44 17375 840BCC

20 12735 A88811 45 35267 152004

21 04262 DD3649 46 36255 0D4897

22 11230 B59F42 47 12044 AF6D25

23 00037 FF81F6 48 26442 4B7593

24 06137 CE8128 49 21621 71BB1B

25 04312 DCD55C 50 25411 53DA0E

Table 18: Base register 2 start values and first code chip for E5a-Q


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8.3.1.3Base register 2 start value for E5b-IThe octal format base register 2 start value with the conventions defined in 416H8.3.1.1 is as

defined in the following 417HTable 18 for each primary code number (1-50).

The hexadecimal format of the first 24 code-chips with the conventions defined in 418H8.3.1.1 is

also given in 419HTable 18.

Code

No

Start

Value

Initial

Sequence

Code

No

Start

Value

Initial

Sequence

1 07220 C5BEA1 26 25664 512FA9

2 26047 4F6248 27 21403 73F36B3 00252 FD5488 28 32253 2D5317

4 17166 86277B 29 02337 EC8390

5 14161 9E39D5 30 30777 380374

6 02540 EA7EDE 31 27122 46B4DE

7 01537 F28321 32 22377 6C01D9

8 26023 4FB0C9 33 36175 0E0BB6

9 01725 F0AB64 34 33075 2708C7

10 20637 79833B 35 33151 265B55

11 02364 EC2D91 36 13134 A68E1C

12 27731 409B11 37 07433 C3916E13 30640 397E16 38 10216 BDC595

14 34174 1E0FCD 39 35466 1327D0

15 06464 CB2F5A 40 02533 EA921F

16 07676 C1079A 41 05351 D45869

17 32231 2D9BC6 42 30121 3EB98A

18 10353 BC5146 43 14010 9FDE16

19 00755 F848B0 44 32576 2A04CA

20 26077 4F01E8 45 30326 3CA56F

21 11644 B16C9B 46 37433 03928A

22 11537 B2827D 47 26022 4FB5B9

23 35115 16C809 48 35770 101EC7

24 20452 7B570F 49 06670 C91D4F

25 34645 1969C0 50 12017 AFC22B

Table 19: Base register 2 start values and first code chip for E5b-I


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8.3.1.4Base register 2 start value for E5b-QThe octal format base register 2 start value with the conventions defined in

420H

8.3.1.1 is asdefined in the following 421HTable 19 for each primary code number (1-50).

The hexadecimal format of the first 24 code-chips with the conventions defined in422H

8.3.1.1 is

also given in 423HTable 19.

Code

No

Start

Value

Initial

Sequence

Code

No

Start

Value

Initial

Sequence

1 03331 E49AF0 26 20134 7E8CFB

2 06143 CE701F 27 11262 B536C3

3 25322 54B709 28 10706 B8E68C

4 23371 641AB1 29 34143 1E7272

5 00413 FBD0AE 30 11051 B75B69

6 36235 0D8BC9 31 25460 533F65

7 17750 805FA5 32 17665 812B41

8 04745 D86BA0 33 32354 2C4DE1

9 13005 A7E921 34 21230 759E2C

10 37140 067E55 35 20146 7E6434

11 30155 3E4B58 36 11362 B43640

12 20237 7D82FB 37 37246 05671B

13 03461 E33BC2 38 16344 8C6FE0

14 31662 31372C 39 15034 978D4E

15 27146 46676F 40 25471 5319BF

16 05547 D2613E 41 25646 516499

17 02456 EB443C 42 22157 6E4292

18 30013 3FD0B1 43 04336 DC86A3

19 00322 FCB7CF 44 16356 8C46BE

20 10761 B83815 45 04075 DF0B03

21 26767 48224A 46 02626 E9A5B2

22 36004 0FEE25 47 11706 B0E553

23 30713 38D33B 48 37011 07DBAC

24 07662 C135B9 49 27041 4778E4

25 21610 71DE13 50 31024 37AF4F

Table 20: Base register 2 start values and first code chips for E5b-Q

8.3.2 E1-B and E1-C Primary Codes

The E1-B and E1-C primary codes are pseudo-random memory code sequences according to

the hexadecimal representation provided in Annex 1.

Note, for each signal component E1-B and E1-C, overall 50 different codes are defined.


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8.4 SECONDARY CODES

8.4.1 Definition of secondary codes

The secondary codes are fixed sequences as defined in hexadecimal notation in 424HTable 20 and

425H

Table 21, following again the convention used in Par.426H

8.3.1.1 extended to codes with length

not being an integer multiple of 4. The n PthP group of four consecutive code-chips in time c B4n-

3B,,cB4nB (in logic level notation) translates into the n Pth

P hexadecimal symbol from the left, the

value defined as 8c B4n-3B + 4cB4n-2B+ 2cB4n-1B + c B4nB. For secondary codes whose length is not

dividable by four (case of CS25 B1B), the last (most right-hand) hexadecimal symbol is obtained

by filling up the last group of code-chips with zeros at the end in time (to the right), to reach a

final length of 4 binary symbols.

The code identifier together with the code length, the number of hexadecimal symbols (range

for n), the hexadecimal representation for the secondary codes and the number of filled zerosare listed in

427H

Table 20 and428H

Table 21.

Notation example: The hexadecimal representation for the CS251 code in 429HTable 20

corresponds to the binary sequence [0 0 1 1 1 0 0 0 0 0 0 0 1 0 1 0 1 1 0 1 1 0 0 1 0], the first

binary value corresponding to the first secondary code chip in time.

Code identifier Code

length

Number of hexadecimal

symbols

Number of filled

up zerosCode sequence (Hexadecimal)

CS4B1B 4 1 0 E

CS20B1B 20 5 0 842E9

CS25B1B 25 7 3 380AD90

CS100 B1B 100 25 0 83F6F69D8F6E15411FB8C9B1C

CS100 B2B 100 25 0 66558BD3CE0C7792E83350525

CS100 B3B 100 25 0 59A025A9C1AF0651B779A8381

CS100 B4B 100 25 0 D3A32640782F7B18E4DF754B7

CS100 B5B 100 25 0 B91FCAD7760C218FA59348A93

CS100 B6B 100 25 0 BAC77E933A779140F094FBF98

CS100 B7B 100 25 0 537785DE280927C6B58BA6776

CS100 B8B 100 25 0 EFCAB4B65F38531ECA22257E2

CS100 B9B 100 25 0 79F8CAE838475EA5584BEFC9B

CS100 B10B 100 25 0 CA5170FEA3A810EC606B66494

CS100 B11B 100 25 0 1FC32410652A2C49BD845E567

CS100 B12B 100 25 0 FE0A9A7AFDAC44E42CB95D261

CS100 B13B 100 25 0 B03062DC2B71995D5AD8B7DBE

CS100 B14B 100 25 0 F6C398993F598E2DF4235D3D5

CS100 B15B 100 25 0 1BB2FB8B5BF24395C2EF3C5A1

CS100 B16B 100 25 0 2F920687D238CC7046EF6AFC9

CS100 B17B 100 25 0 34163886FC4ED7F2A92EFDBB8

CS100 B18B 100 25 0 66A872CE47833FB2DFD5625AD

CS100 B19B 100 25 0 99D5A70162C920A4BB9DE1CA8

CS100 B20B 100 25 0 81D71BD6E069A7ACCBEDC66CA

CS100 B21B 100 25 0 A654524074A9E6780DB9D3EC6

CS100 B22B 100 25 0 C3396A101BEDAF623CFC5BB37

CS100 B23B 100 25 0 C3D4AB211DF36F2111F2141CD


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CS100 B24B 100 25 0 3DFF25EAE761739265AF145C1

CS100 B25B 100 25 0 994909E0757D70CDE389102B5

CS100 B26B 100 25 0 B938535522D119F40C25FDAEC

CS100 B27B 100 25 0 C71AB549C0491537026B390B7

CS100 B28B 100 25 0 0CDB8C9E7B53F55F5B0A0597B

CS100 B29B 100 25 0 61C5FA252F1AF81144766494F

CS100 B30B 100 25 0 626027778FD3C6BB4BAA7A59D

CS100 B31B 100 25 0 E745412FF53DEBD03F1C9A633

CS100 B32B 100 25 0 3592AC083F3175FA724639098

CS100 B33B 100 25 0 52284D941C3DCAF2721DDB1FD

CS100 B34B 100 25 0 73B3D8F0AD55DF4FE814ED890

CS100 B35B 100 25 0 94BF16C83BD7462F6498E0282

CS100 B36B 100 25 0 A8C3DE1AC668089B0B45B3579

CS100 B37B 100 25 0 E23FFC2DD2C14388AD8D6BEC8

CS100 B38B 100 25 0 F2AC871CDF89DDC06B5960D2B

CS100 B39B 100 25 0 06191EC1F622A77A526868BA1

CS100 B40B 100 25 0 22D6E2A768E5F35FFC8E01796

CS100 B41B 100 25 0 25310A06675EB271F2A09EA1D

CS100 B42B 100 25 0 9F7993C621D4BEC81A0535703

CS100 B43B 100 25 0 D62999EACF1C99083C0B4A417

CS100 B44B 100 25 0 F665A7EA441BAA4EA0D01078C

CS100 B45B 100 25 0 46F3D3043F24CDEABD6F79543

CS100 B46B 100 25 0 E2E3E8254616BD96CEFCA651A

CS100 B47B 100 25 0 E548231A82F9A01A19DB5E1B2

CS100 B48B 100 25 0 265C7F90A16F49EDE2AA706C8

CS100 B49B 100 25 0 364A3A9EB0F0481DA0199D7EA

CS100 B50B 100 25 0 9810A7A898961263A0F749F56

Table 21: Secondary code sequences (Part 1)

Code identifier Code

length

Number of hexadecimal

symbols

Number of filled

up zerosCode sequence (Hexadecimal)

CS100B51B 100 25 0 CFF914EE3C6126A49FD5E5C94

CS100B52B 100 25 0 FC317C9A9BF8C6038B5CADAB3

CS100B53B 100 25 0 A2EAD74B6F9866E414393F239

CS100B

54B

100 25 0 72F2B1180FA6B802CB84DF997CS100B55B 100 25 0 13E3AE93BC52391D09E84A982

CS100B56B 100 25 0 77C04202B91B22C6D3469768E

CS100B57B 100 25 0 FEBC592DD7C69AB103D0BB29C

CS100B58B 100 25 0 0B494077E7C66FB6C51942A77

CS100B59B 100 25 0 DD0E321837A3D52169B7B577C

CS100B60B 100 25 0 43DEA90EA6C483E7990C3223F

CS100B61B 100 25 0 0366AB33F0167B6FA979DAE18

CS100B62B 100 25 0 99CCBBFAB1242CBE31E1BD52D

CS100B63B 100 25 0 A3466923CEFDF451EC0FCED22

CS100B64B 100 25 0 1A5271F22A6F9A8D76E79B7F0

CS100B65

B 100 25 0 3204A6BB91B49D1A2D3857960


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CS100B66B 100 25 0 32F83ADD43B599CBFB8628E5B

CS100B67B 100 25 0 3871FB0D89DB77553EB613CC1

CS100B68B 100 25 0 6A3CBDFF2D64D17E02773C645

CS100B69B 100 25 0 2BCD09889A1D7FC219F2EDE3B

CS100B70B 100 25 0 3E49467F4D4280B9942CD6F8C

CS100B71B 100 25 0 658E336DCFD9809F86D54A501

CS100B72B 100 25 0 ED4284F345170CF77268C8584

CS100B73B 100 25 0 29ECCE910D832CAF15E3DF5D1

CS100B74B 100 25 0 456CCF7FE9353D50E87A708FA

CS100B75B 100 25 0 FB757CC9E18CBC02BF1B84B9A

CS100B76B 100 25 0 5686229A8D98224BC426BC7FC

CS100B77B 100 25 0 700A2D325EA14C4B7B7AA8338

CS100B78B 100 25 0 1210A330B4D3B507D854CBA3F

CS100B79B 100 25 0 438EE410BD2F7DBCDD85565BA

CS100B80B 100 25 0 4B9764CC455AE1F61F7DA432B

CS100B81B 100 25 0 BF1F45FDDA3594ACF3C4CC806

CS100B82B 100 25 0 DA425440FE8F6E2C11B8EC1A4

CS100B83B 100 25 0 EE2C8057A7C16999AFA33FED1

CS100B84B 100 25 0 2C8BD7D8395C61DFA96243491

CS100B85B 100 25 0 391E4BB6BC43E98150CDDCADA

CS100B86B 100 25 0 399F72A9EADB42C90C3ECF7F0

CS100B87B 100 25 0 93031FDEA588F88E83951270C

CS100B88B 100 25 0 BA8061462D873705E95D5CB37

CS100B89B 100 25 0 D24188F88544EB121E963FD34

CS100B90B 100 25 0 D5F6A8BB081D8F383825A4DCA

CS100B91B 100 25 0 0FA4A205F0D76088D08EAF267

CS100B92B 100 25 0 272E909FAEBC65215E263E258

CS100B93B 100 25 0 3370F35A674922828465FC816

CS100B94B 100 25 0 54EF96116D4A0C8DB0E07101F

CS100B95B 100 25 0 DE347C7B27FADC48EF1826A2B

CS100B96B

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