MLT-EICD Issue 2.1 - European Space Agencyemits.sso.esa.int/emits-doc/ESTEC/20060512_GIS-REQ-004-IE_MLT-E… · RD-04 GISAR Glossary (GISGLO) Ref.: GIS-TN-005-IE RD-05 Guidelines

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MEOLUT Prototype External Interface Control Document Page 2 de 27 INDRA ESPACIO S.A. owns the copyright of this document which shall not be used for any purpose other than for which it is supplied and shall not be copied or given to any person or organization without written authorization from the owner.

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Archive 1 Indra Espacio 1

Document Change Log

Iss./Rev. Date Section / Page Change Description

Issue 1 09/09/2005 - Document creation.

Issue 1.1 08/11/2005 - Update based on comments from CNES.

Issue 1.2 12/12/2005 p. 14, 17 Update of Satellite Ephemeris Message and corresponding MFs. Inclusion of new “UTC CONVERSION” MF.

Issue 2.0 07/04/2006 All

Add information for Tracking DASS POC satellites

Add miscellaneous information regarding messages description and format

Review of the document

This issue is part of the CDR datapackage.

Contents Table of Contents actualised according to rearrangement in section 2.2

Section 2.2.1 Rewrite as per CDR DRS comment. Issue 2.1 12/05/2006

This issue is part of the CDR Close-out datapackage.

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Contents

1. INTRODUCTION .............................................................................................................4 1.1 OBJECTIVE ....................................................................................................................4 1.2 APPLICABLE DOCUMENTS ..............................................................................................4 1.3 REFERENCE DOCUMENTS ..............................................................................................4 1.4 ACRONYMS AND TERMS.................................................................................................5 1.5 TBC/TBD LIST...............................................................................................................6 2. EXTERNAL INTERFACE DEFINITION...........................................................................8 2.1 OVERVIEW.....................................................................................................................8

2.1.1 Terminology .........................................................................................................8 2.1.2 Interface overview................................................................................................8

2.2 MEOLUT EXTERNAL INTERFACES................................................................................10 2.2.1 SAR downlink SIS..............................................................................................10

2.2.1.1 Signal in DASS POC satellites.......................................................................10 2.2.2 GPS SIS.............................................................................................................10 2.2.3 MCC...................................................................................................................10

2.2.3.1 Overview of the interface ...............................................................................10 2.2.3.2 Physical characteristics..................................................................................10 2.2.3.3 Protocols ........................................................................................................10

2.2.3.3.1 Low-level protocols ................................................................................................10 2.2.3.3.2 High-level protocols ...............................................................................................10

2.2.3.4 Messages.......................................................................................................10 2.2.3.4.1 SAR Distress Data .................................................................................................10 2.2.3.4.2 External TOA/FOA Pairs Request .........................................................................10 2.2.3.4.3 External TOA/FOA Pairs Message ........................................................................10 2.2.3.4.4 Satellite Ephemeris Message ................................................................................10 2.2.3.4.5 Satellite Status .......................................................................................................10 2.2.3.4.6 Service Bulletins ....................................................................................................10

2.2.3.5 Message Fields Description ...........................................................................10

List of Figures FIGURE 1: MEOLUT HIGH-LEVEL PHYSICAL ARCHITECTURE........................................................9 FIGURE 2: SPACE SEGMENT DIAGRAM OF DASS PROOF OF CONCEPT FUNCTIONS ...................10 FIGURE 3: DASS SIGNAL FREQUENCY TRANSLATION ................................................................10

List of Tables TABLE 1: MESSAGE CONTENT FOR SAR DISTRESS DATA MESSAGE FOR LOCATED ALERTS.......10 TABLE 2: MESSAGE CONTENT FOR SAR DISTRESS DATA MESSAGE FOR UNLOCATED ALERTS ..10 TABLE 3: MESSAGE CONTENT FOR EXTERNAL TOA/FOA PAIRS REQUEST MESSAGE................10 TABLE 4: MESSAGE CONTENT FOR EXTERNAL TOA/FOA PAIRS MESSAGE ...............................10 TABLE 5: MESSAGE CONTENT FOR SATELLITE EPHEMERIS MESSAGE .......................................10 TABLE 6: MESSAGE CONTENT FOR SATELLITE STATUS MESSAGE .............................................10 TABLE 7: MESSAGE CONTENT FOR SERVICE BULLETIN MESSAGE .............................................10 TABLE 8: NEW OR MODIFIED MESSAGE FIELDS.........................................................................10

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1. INTRODUCTION

1.1 OBJECTIVE

The purpose of this document is to provide a detailed description of the interface between the MEOLUT Prototype and the External entities with which it communicates.

The interface between a LUT and an MCC is not formally defined by C/S (see 3.4.1, 3.5.1 of RD-03). However, given that the MCC has to communicate with other MCCs in the format described in RD-02, many LUTs follow the interface defined in this document to facilitate implementation. RD-02 covers the communication required for the LEOSAR and GEOSAR systems. The full description of the different messages is not included in this document (refer to RD-02), only updates or additions are proposed to cover the functionality of the MEOSAR system. The document follows the structure described in RD-05, although for convenience and given that most of the interface is the same, the description for this interface follows the standard interface description used in RD-02.

1.2 APPLICABLE DOCUMENTS

AD-01 Cospas-Sarsat Galileo ICD, (COSSARGALICD) Ref.: GAL-ID-GLI-SYST-A-0375, Is. 6, Rev. 0, 19/01/2005

1.3 REFERENCE DOCUMENTS

RD-01 External Interface Management Module Requirements Document (EIMM-REQ) Ref.: GIS-TN-007-IE, Issue 1.2, 01/06/2005

RD-02 Cospas-Sarsat Mission Control Centres Standard Interface Description Ref.: C/S A.002, Is. 4, Rev. 8, October 2004

RD-03 Cospas-Sarsat Mission Control Centre (MCC) Performance Specification And Design Guidelines Ref.: C/S A.005, Is. 3, Rev. 2, October 2002

RD-04 GISAR Glossary (GISGLO) Ref.: GIS-TN-005-IE

RD-05 Guidelines for GISAR ICDs Ref: GIS-MSC-001-IE, Issue 1, 27/05/2005

RD-06 Global Positioning System Standard Positioning Service Signal Specification Ref.: 2nd Edition, June 2, 1995

RD-07 Minimum Operational Performance Standards for Global Positioning System/Wide Area Augmentation System Airborne Equipment Ref.: RTCA/DO-229

RD-08 Cospas-Sarsat Data Distribution Plan Ref: C/S A.001, Is. 4, Rev. 7, October 2004

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RD-09 Cospas-Sarsat 406 MHz MEOSAR Implementation Plan Ref.: C/S R.012, Is. 1, October 2004

RD-10 Forward Link Service Operations & Service Possibilities Report Ref.: GIS-TN-002-CNES, Issue 1.0, 20/06/2005

RD-11 Return Link Service Operations & Service Possibilities Report Ref.: GIS-TN-001-CNES, Issue 1.2, 20/06/2005

1.4 ACRONYMS AND TERMS

Acronym Description ACU Antenna Control Unit

AD Applicable Document

AFTN Aeronautical Fixed Telecommunication Netwok

AGC Automatic Gain Control

AMHS Aeronautical Message Handling System

CP Core Processor

CPS Core Processor Set

DASS Distress Alerting Satellite System

DDC Digital Down-Converter (part of the FES)

EIRP Equivalent Isotropic Radiated Power

FES Front-End Set

FESA Front-End-Set Adaptor (Sofware module within the CPS)

FOA Frequency of Arrival

FTP File Transfer Protocol

GMS Ground Mission Segment

GNSS Global Navigation Satellite System

IE Indra Espacio

LHCP Left-Hand Circular Polarisation

LODU Local Oscillator Distribution Unit (part of the FES)

LUT Local User Terminal

[M] Mandatory [section]

M&C Monitoring and Control

MCC Mission Control Centre

MEOLUT Medium-Altitude Earth Orbit Local User Terminal

MEOSAR Medium-Altitude Earth Orbit Search and Rescue

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MF Message Field

N/A Not Applicable

POC Proof Of Concept

PPS Pulse Per Second

RD Reference Document

RFE Radio Frequency Equipment (part of the FES)

RHCP Right-Hand Circular Polarisation

RLM Return Link Message

RLSP Return Link Service Provider

RXS Receiver Set

SAR Search And Rescue

SIS Signal In Space

SIT Subject Indicator Type

SNMP Simple Network Management Protocol

SW SoftWare

TAS Thales Airborne Systems

TBC To Be Confirmed

TBD To Be Determined

TFR Time and Frequency Reference

TOA Time of Arrival

UTC Universal Time Coordinated

UTP Unshielded Twisted Pair

See also RD-04.

1.5 TBC/TBD LIST

Section TBC 2.2.3.2 Physical characteristics of the connection between the MEOLUT Prototype

and the MCC

Section TBD 2.2.3.2 mode and features of the physical connection between the MEOLUT

Prototype and the MCC

2.2.3.2 Details on the exact configuration, security and detailed characteristics of the physical connection between the MEOLUT Prototype and the MCC

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2.2.3.3.1 Details on the exact configuration, security and detailed characteristics of the low level communication protocol between the MEOLUT Prototype and the MCC

2.2.3.3.2 Details on the exact configuration, security and detailed characteristics of the high level communication protocol between the MEOLUT Prototype and the MCC

2.2.3.4.1 New SITs number for the transmission of SAR Distress Data between MEOLUT and MCCs

2.2.3.4.1 Several MF# number in SIT for located SAR distress data

2.2.3.4.1 Several MF# number in SIT for unlocated SAR distress data

2.2.3.4.2 New SIT number for external TOA/FOA Pairs Request

2.2.3.4.2 Several MF# number in external TOA/FOA Pairs Request Message

2.2.3.4.3 New SIT number for external TOA/FOA Pairs Message

2.2.3.4.3 Several MF# number in external TOA/FOA Pairs Message

2.2.3.4.4 New SIT number for Satellite Ephemeris Message

2.2.3.4.4 Several MF# number in Satellite Ephemeris Message

2.2.3.4.5 New SIT number for MEOSAR Satellites Status Message

2.2.3.4.5 Several MF# number in MEOSAR Satellites Status Message

2.2.3.4.6 New SIT number for Service Bulletin Message

2.2.3.4.6 Several MF# number in Service Bulletin Message

2.2.3.5 Several MF# number in message fields descriptions

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2. EXTERNAL INTERFACE DEFINITION

2.1 OVERVIEW

2.1.1 Terminology

For aspects related to interfaces and data definition the following levels exist (based on Galileo interface definitions):

1. Interface: as the whole means for communication or interaction between interfaced elements. Example: FES-RXS interface

2. Link: as a connection inside an interface for a given kind of information transfer. Examples: a LAN network link for transferring data between two Sets or a 1 PPS connection.

3. Channel: port-to-port connection paths within a given link. For data transfers, a channel is usually a logical connection through the network. Data transfers through the channel are usually implemented by means of messages.

4. Data: encoded information that flows through the channel. Example: Data are usually encapsulated into the message body. Note that a given data can flow through (a cascade) of different interfaces-links-channels.

2.1.2 Interface overview

The MEOLUT high-level physical architecture is described in Figure 1 below and presents the main components and associated interfaces.

The external interfaces, object of this ICD, are highlighted in red.

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Figure 1: MEOLUT high-level physical architecture

The figure shows that the MEOLUT Prototype external interfaces are:

1. SAR downlink SIS: SAR/Galileo Signal in Space in L-band relaying the beacon distress signals. In the final operational MEOLUT, this could also apply to signals relayed by the DASS system.

2. GPS SIS: Navigation signals of the GPS system used for time synchronisation purposes. In the final operational MEOLUT, this could be replaced by navigation signals relayed by the Galileo system.

3. Interface with C/S: External communications with the C/S MCC.

Data flows MEOLUT components

Front-End Set (FES)

CoreProcessor Set

(CPS)

MEOSAR satellites

GPSconstellation

SAR Downlink SIS

GPSSIS

Network - MCC

SAR Streams

Raw STS Parameters

Frequency Standard

1PPS

RFE Command

DDC Response

DDC Command

RXS Response RXS Command

SAR Distress Data

RFE Response

Receiver Set (RXS)

Ext. TOA/FOARequest

Satellite Ephemeris,Satellite Status,TBD[Service Bulletins]

External TOA/FOA Pairs

UTC Time

Downlink Description

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2.2 MEOLUT EXTERNAL INTERFACES

2.2.1 SAR downlink SIS

SAR/Galileo SIS interface is fully described in Volume 2 of AD-01. This interface covers the LHCP L-band (1544.100 MHz) transmission of the SAR/Galileo signals from the Galileo satellites relaying distress beacon signals.

DASS SIS is described in section 2.2.1.1.

2.2.1.1 Signal in DASS POC satellites

The DASS signals are SAR signals relayed by repeaters on board several GPS satellites.

DASS Repeater Configuration A diagram of the space segment DASS POC functions is shown in Figure 2.

Figure 2: Space Segment Diagram of DASS Proof of Concept Functions

≈

Local Oscillator

Generation

3 dB BW = 200 kHz

LNA Up

Converter

2226.472340 MHz

Power Amp.

406.05 MHz

Down Converter

UHF Antenna LHCP

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The following parameters are provided for establishing link budgets to track the DASS POC satellites.

• 406 MHz Antenna Polarization is LHCP

• G/T = -17.7 dB/K at 406 MHz

• Receiver operates with AGC

• Channel bandwidth approximately 200 kHz

• Receiver is frequency translation from 406 MHz to S-band with no re-modulation.

• S-band downlink antenna is LHCP

• Downlink EIRP is ≈ 10dBW

The receiver frequency conversion process inverts the 406.0 to 406.1 MHz distress beacon band as it is being translated to S-Band as follows.

fSb = 2226.472340 + (406.05 - fb)

where:

fSb = beacon frequency embedded in S-band downlink

fb = beacon transmit frequency (from 406.0 to 406.1 MHz)

(i.e. for fb = 406.025 MHz, fSb= 2226.497340 MHz)

406.05 MHz = center of beacon transmit band

2226.472340 MHz = center of beacon band in the S-band downlink

The DASS POC frequency translation is graphically shown in the following diagram.

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406.0 406.1 406.05

2226.4723402226.522340 2226.422340

All frequency in MHz

Figure 3: DASS signal frequency translation

As noted above, the repeater bandwidth is 200 kHz. The S-band downlink emission, therefore, spans a frequency range from approximately 2226.372340 to 2226.572340 MHz. Emitters operating in the mobile service in the region just above 406.1 MHz are often seen at frequencies below 2226.422340 MHz.

2.2.2 GPS SIS

This interface is fully described in RD-06. This corresponds to the definition of the navigation signals for the GPS system. This navigation signal is used for time synchronisation of the TFR subsystem through a standard GPS receiver.

In the future, a MEOLUT could replace the GPS receiver by a Galileo receiver to perform the same function.

2.2.3 MCC

2.2.3.1 Overview of the interface

This interface is used to transmit alerts and other data to the C/S MCC and to receive from it certain parameters (RD-01).

In C/S, the definition of the interface between LUTs and MCCs is not standardised and is left for the national administrations to define (see 3.4.1, 3.5.1 of RD-03). The interface between MCCs, however, is formally standardised by C/S within RD-02. The data transmitted between MCCs is very often of the same characteristics as the data exchanged between a LUT and its MCC. Therefore, many LUTs use the same type of interface to communicate with their MCC in order to facilitate implementation.

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This document assumes that the interface between the MEOLUT Prototype and its corresponding MCC will follow the specifications defined in RD-02. There are, however, certain characteristics that are particular to the MEOSAR system. Therefore, the full description of the different messages is not included in this document (refer to RD-02), only updates or additions are proposed to cover the functionality of the MEOSAR system.

For convenience, the description for this interface follows the standard interface description used in RD-02.

This interface is composed of a single link and a single channel (as defined in section 2.1).

2.2.3.2 Physical characteristics

The physical characteristics for the connection between the MEOLUT Prototype and the MCC shall be as follows [TBC]:

• Ethernet compliant to norm IEEE 802.3

• 100 Mbit/s, mode and features TBD

• cables are shielded twisted pair category 5 with RJ45 connector

• both elements provide Ethernet interface as a female RJ45 socket of MDI type

Details on the exact configuration, security and detailed characteristics are [TBD].

2.2.3.3 Protocols

2.2.3.3.1 Low-level protocols

Communications between the MEOLUT Prototype and the MCC shall be based on TCP/IP.


2.2.3.3.2 High-level protocols

The protocols used by MCC to communicate with each other are X.25 Communications (being phased-out), File Transfer Protocol (FTP) Communications, Telex Communications (being phased-out) and AFTN Communications (being upgraded to AMHS).

Communications between the MEOLUT Prototype and the MCC shall be based on FTP as described in RD-02.


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2.2.3.4 Messages

The following sections describe the different messages that are necessary to be exchanged between the MEOLUT Prototype and the MCC. Refer to section 2.2.3.5 for a description of modified or new Message Fields.

2.2.3.4.1 SAR Distress Data

The Cospas-Sarsat inter-MCCs interface for exchanging 406 MHz SAR alert data uses SITs 122-133. In practice, a LUT only needs to transmit two different types of SAR Alerts to its associated MCC: Unlocated Alerts, and Located Alerts (SITs 122 and 125 respectively).

New SITs (numbers TBD) for the transmission of 406 MHz Beacon Alert data from the MEOLUT to its associated MCC shall be transmitted in accordance with Table 1 for Located Alerts and Table 2 for Unlocated Alerts:

MESSAGE FORMAT MF# TITLE MESSAGE HEADER 1 MESSAGE NUMBER

2 REPORTING MCC

3 MESSAGE TRANSMIT TIME

SIT HEADER 4 SIT

5 SIT DESTINATION

8 NUMBER OF ALERTS WITH DOPPLER POSITIONS

SOLUTION HEADER 11 SOURCE ID

23 406 MESSAGE

21 NUMBER OF POINTS

TBD SATELLITES FOR RLM

BURST DATA TBD BEACON TRANSMIT TIME

TBD NUMBER OF TOA/FOA PAIRS

LINK DATA 6 SPACECRAFT ID

TBD UPLINK TOA

TBD UPLINK FOA

TBD CARRIER TO NOISE DENSITY RATIO

REPEAT MFs OF LINK DATA AS REQUIRED BY “NUMBER OF TOA/FOA PAIRS”

REPEAT MFs OF BURST DATA AND LINK DATA AS REQUIRED BY “NUMBER OF POINTS”

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MESSAGE FORMAT MF# TITLE SOLUTION DATA 25 LATITUDE

26 LONGITUDE

TBD ALTITUDE

TBD ESTIMATED ERROR RADIUS1

REPEAT MFs OF SOLUTION HEADER, BURST DATA, LINK DATA AND SOLUTION DATA AS REQUIRED BY MF #8 OR #10

SIT TRAILER 42 ENDSIT

MSG TRAILER 43 ENDMSG

Table 1: Message Content for SAR Distress Data Message for Located Alerts

Note that “ALTITUDE” is also included in the Solution Data in order to provide a 3D location. Compared to the LEOSAR and GEOSAR system, alerts are no longer grouped by “SPACECRAFT ID” given that, in general, several satellites will be simultaneously in view of a beacon or MEOLUT.

A new SIT (number TBD) would be used for alerts where location information based on TOA/FOA is not available (Table 2).


2 REPORTING MCC


SIT HEADER 4 SIT

5 SIT DESTINATION

10 NUMBER OF ALERTS WITHOUT DOPPLER POSITIONS

SOLUTION HEADER 11 SOURCE ID

23 406 MESSAGE

21 NUMBER OF POINTS

TBD SATELLITES FOR RLM

BURST DATA TBD BEACON TRANSMIT TIME


1 Represents the 50%-probability area of the real beacon location (centred at the calculated location). .

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MESSAGE FORMAT MF# TITLE LINK DATA 6 SPACECRAFT ID

TBD UPLINK TOA

TBD UPLINK FOA



REPEAT MFs OF BURST DATA AND LINK DATA AS REQUIRED BY “NUMBER OF POINTS”

REPEAT MFs OF SOLUTION HEADER, BURST DATA AND LINK DATA AS REQUIRED BY MF #10



Table 2: Message Content for SAR Distress Data Message for Unlocated Alerts

2.2.3.4.2 External TOA/FOA Pairs Request

For the requests from the MEOLUT to the MCC to provide TOA/FOA pairs originating at other MEOLUTs corresponding to a particular burst transmission, a new SIT (number TBD) is proposed that would be composed in accordance with the following table:


2 REPORTING MCC


SIT HEADER 4 SIT

5 SIT DESTINATION

SIT BODY 11 SOURCE ID

TBD NUMBER OF ALERTS

REQUEST DATA 22 BEACON ID

TBD BEACON TRANSMIT TIME

REPEAT MFs OF REQUEST DATA AS REQUIRED BY “NUMBER OF ALERTS”



Table 3: Message Content for External TOA/FOA Pairs Request Message

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A new MF has been added “NUMBER OF ALERTS” to avoid confusion with “NUMBER OF POINTS”, which refer to transmissions of the same beacon.

2.2.3.4.3 External TOA/FOA Pairs Message

The sharing of TOA/FOA information among MEOLUTs is planned for the MEOSAR system in order to maximise beacon localisation and expand the coverage of MEOLUTs (see §8.1 of RD-09).

The new SIT (number TBD) is proposed that would be composed of the following Message Fields:


2 REPORTING MCC


SIT HEADER 4 SIT

5 SIT DESTINATION

TBD NUMBER OF ALERTS

RESPONSE DATA 11 SOURCE ID

22 BEACON ID

TBD BEACON TRANSMIT TIME


LINK DATA 6 SPACECRAFT ID

TBD UPLINK TOA

TBD UPLINK FOA



REPEAT MFs OF RESPONSE DATA AND LINK DATA AS REQUIRED BY “NUMBER OF ALERTS”



Table 4: Message Content for External TOA/FOA Pairs Message

The “BEACON TRANSMIT TIME” is used to identify a specific burst transmission of a particular beacon. The “UPLINK TOA” and “UPLINK FOA” provide the Time Of Arrival and Frequency Of Arrival of the beacon burst at the satellite.

“SOURCE ID” provides information about the originating MEOLUT of the TOA/FOA pairs.

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2.2.3.4.4 Satellite Ephemeris Message

This message intends to provide the MEOLUT Prototype with information regarding Galileo satellites ephemeris. A new Subject Indicator Type (SIT, see RD-02) message is proposed (SIT number TBD), similar to existing SIT numbers 215 and 216, with the following fields:


2 REPORTING MCC


SIT HEADER 4 SIT

5 SIT DESTINATION

44 NUMBER OF SPACECRAFT

TBD UTC CONVERSION

SIT BODY 6 SPACECRAFT ID

TBD EPHEMERIS

REPEAT MFs OF SIT BODY AS REQUIRED BY “NUMBER OF SPACECRAFT”



Table 5: Message Content for Satellite Ephemeris Message

The new “UTC CONVERSION” MF is included in order to be able to refer to the MEOSAR System Time in which ephemeris is provided, considering that the MEOLUT operates in UTC.

The new “EPHEMERIS” MF is included to adequate satellite positioning information to the usual format transmitted by MEOSAR constellations in their navigation message.

The “SPACECRAFT ID” (MF #6) correspondence table has been expanded in order to be able to identify MEOSAR satellites (see section 2.2.3.5).

2.2.3.4.5 Satellite Status

Satellite status is currently provided in text form through SIT 605. The contents of the text message are described in Annex II / F of RD-08.

For Galileo, the Galileo Ground Mission Segment is expected to provide useful status information like:

- current satellite status: for each satellite, SAR functions available for Forward Link, Navigation functions available for Return Link

- service bulletins: planned Forward Link outages, planned Return Link outages, planned RLSP-GMS changes

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This status information should be provided to the MEOLUT in order to optimise operations like satellite tracking.

Given that the number of satellites will significantly increase with the arrival of the MEOSAR constellations, an alternative to provide increased automation by means of specific Message Fields (and SITs) is considered.

The new SIT (number TBD) for Satellite Status would follow Table 6:


2 REPORTING MCC


SIT HEADER 4 SIT

5 SIT DESTINATION



TBD FORWARD LINK STATUS

TBD CENTER FREQUENCY

TBD POLARIZATION

TBD GAIN CONTROL

TBD BANDWIDTH

TBD TRANSPONDER DELAY

TBD RETURN LINK STATUS




Table 6: Message Content for Satellite Status Message

2.2.3.4.6 Service Bulletins

A new SIT for Service Bulletins has been defined.

Following the strategy for the Satellite Status Message, in which the NARRATIVE field has been replaced by dedicated fields allowing automatic processing, the proposed message structure is defined in

This new SIT (number TBD) for Service Bulletins would follow Table 7:

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2 REPORTING MCC


SIT HEADER 4 SIT

5 SIT DESTINATION

TBD PLANNED GMS-RLSP INTERFACE OUTAGE

TBD GMS-RLSP I/F OUTAGE START TIME

TBD GMS-RLSP I/F OUTAGE END TIME



TBD STATUS OF MANOEUVRE

TBD TYPE OF MANOEUVRE

TBD SAR FORWARD LINK ACTIVE DURING MANOEUVRE

TBD SAR RETURN LINK ACTIVE DURING MANOEUVRE

TBD MANOEUVRE START TIME

TBD MANOEUVRE END TIME

TBD TIME OF NEW EPHEMERIS




Table 7: Message Content for Service Bulletin Message

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2.2.3.5 Message Fields Description

This section is an update of Annex B of RD-02. It contains modifications of existing Message Fields (MF) or additions required to transmit information which is specific of the MEOSAR system. MF# NAME CONTENT CHARACTER TEXT 6 SPACECRAFT ID SARSAT = 001 -> 099

COSPAS = 101 -> 199 GOES = 201 -> 220 LUCH-M = 221 -> 240 INSAT-2, INSAT-3 = 241 -> 260 MSG = 261 -> 280 MEO PRN x = 300 + x (MEO includes GPS, GLONASS, Galileo)2 (See Annex II/F in C/S A.001 for spacecraft status)

nnn

25 LATITUDE (DEGREES)3

LAT: ±00.000 -> ±90.000 WHERE: + = NORTH and - = SOUTH

snn.nnnn

26 LONGITUDE (DEGREE)3

LONG: ±000.000 -> ±180.000 WHERE: + = EAST and - = WEST

snnn.nnnn

2 From RD-07:

PRN Slot Assignment 1-37 GPS/GPS Reserved 38-61 GLONASS 62-119 Future GNSS (to include Galileo) 120-138 GEO/WAAS 139-210 Future GNSS/GEO/WAAS/Pseudolites 3 Expanded resolution to provide increased accuracy.

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MF# NAME CONTENT CHARACTER TEXT [TBD] BEACON

TRANSMIT TIME YEAR = 00->99 DAY (JULIAN) = 001-> 366 UTC – HRS = 00 -> 23 MINS = 00 -> 59 SECONDS = 00 -> 59 Note: “Beacon transmit time” identifies a particular beacon burst transmission. For burst transmission association among LUTs a ±1 s tolerance shall be considered. If Beacon Transmit Time is all set to zeroes in a request, it refers to all beacon burst transmissions of the beacon alert since the last request.

nn nnn nnnnnn

[TBD] NUMBER OF TOA/FOA PAIRS

01 -> 99 nn

[TBD] UPLINK TOA YEAR = 00->99 DAY (JULIAN) = 001-> 366 UTC – HRS = 00 -> 23 MINS = 00 -> 59 SECONDS = 00.000000 -> 59.999999

nn nnn nnnnnn.nnnnnn

[TBD] UPLINK FOA (Hz)

000000000.00 Hz -> 999999999.99 Hz nnnnnnnnn.nn

[TBD] NUMBER OF ALERTS

01 -> 99 nn

[TBD] UTC CONVERSION

# Parameter Definition Scale factor

Unit

1 A0 Constant term of polynomial 2-30 seconds snnnnnnnnnn 2 A1 1st order term of polynomial 2-50 s/s snnnnnnn 3 ∆tLS Delta time due to leap seconds 1 seconds snnn 4 t0t Reference time for UTC data 1 seconds nnnnnn 5 WNt UTC reference Week Number 1 weeks nnn 6 WNLSF Week Number of the Leap Second 1 weeks nnn 7 DN Day Number of the Leap Second 1 …7 days n 8 ∆tLSF Delta time due to leap second 1 seconds snnn [TBD] EPHEMERIS # Parameter Definition Scale

factor Unit

1 M0 Mean Anomaly at Reference Time 2-31 Semi-circles snnnnnnnnnn 2 ∆n Mean Motion Difference From Computed

Value 2-43 Semi-circles/s snnnnn

3 e Eccentricity 2-33 N/A nnnnnnnnnn 4 (A)1/2 Square Root of the Semi-Major Axis 2-19 Meters1/2 nnnnnnnnnn 5 (OMEGA)0 Longitude of Ascending Node of Orbit 2-31 Semi-circles snnnnnnnnnn

GISAR

Ref.:

Iss./Rev.:

Date:

GIS-REQ-004-IE

2.1

12/05/2006


MF# NAME CONTENT CHARACTER TEXT Plane at Weekly Epoch

6 i0 Inclination Angle at Reference Time 2-31 Semi-circles snnnnnnnnnn 7 ω Argument of Perigee 2-31 Semi-circles snnnnnnnnnn 8 OMEGADOT Rate of Right Ascension 2-43 Semi-circles/s snnnnnnn 9 IDOT Rate of Inclination Angle 2-43 Semi-circles/s snnnn 10 Cuc Amplitude of the Cosine Harmonic

Correction Term to the Argument of Latitude

2-29 Radians snnnnn

11 Cus Amplitude of the Sine Harmonic Correction Term to the Argument of Latitude

2-29 Radians snnnnn

12 Crc Amplitude of the Cosine Harmonic Correction Term to the Orbit Radius

2-5 Meters snnnnn

13 Crs Amplitude of the Sine Harmonic Correction Term to the Orbit Radius

2-5 Meters snnnnn

14 Cic Amplitude of the Cosine Harmonic Correction Term to the Angle of Inclination

2-29 Radians snnnnn

15 Cis Amplitude of the Sine Harmonic Correction Term to the Angle of Inclination

2-29 Radians snnnnn

16 t0e Ephemeris Reference time 1 seconds nnnnnn 17 WNe Ephemeris reference week number 1 weeks nnnn 18 IOD Issue of Ephemeris Data N/A N/A nnn [TBD] ALTITUDE4 ±00000 m -> ±99999 m snnnnn [TBD] SATELLITES

FOR RLM 10 PRN numbers (see MF 6) (Default values are 000)

nnnbnnnbnnnbnnnbnnnbnnnbnnnbnnnbnnnbnnn

[TBD] FORWARD LINK STATUS

0 -> 9 0: Normal 1: Degraded 2: Unusable 3-9: Spare

n

[TBD] CENTER FREQUENCY

0000000000.00 Hz -> 9999999999.99 Hz nnnnnnnnnn.nn

4 Signed value needed, as some geographic areas on the geoid are below altitude zero of the reference ellipsoid.

GISAR

Ref.:

Iss./Rev.:

Date:

GIS-REQ-004-IE

2.1

12/05/2006


MF# NAME CONTENT CHARACTER TEXT [TBD] POLARIZATION 0 -> 9

0: RHCP 1: LHCP

n

[TBD] GAIN CONTROL 0 -> 9 0: Automatic 1: Fixed 2-9: Spare

n

[TBD] BANDWIDTH 000 kHz -> 999 kHz nnn [TBD] TRANSPONDER

DELAY 000.00 µs -> 999.99 µs nnn.nn

[TBD] RETURN LINK STATUS

0 -> 9 0: Normal 1: Degraded 2: Unusable 3-9: Spare

n

[TBD] CARRIER TO NOISE DENSITY RATIO

00.00 dBHz -> 99.99 dBHz nn.nn

[TBD] ESTIMATED ERROR RADIUS

00.00 km -> 99.99 km nn.nn

[TBD] PLANNED GMS-RLSP INTERFACE OUTAGE

0=no 1=yes (+ spare values up to 9)

n

[TBD] GMS-RLSP I/F OUTAGE START TIME

YEAR = 00->99 DAY (JULIAN) = 001-> 366 UTC – HRS = 00 -> 23 MINS = 00 -> 59 SECONDS = 00 -> 59

nn nnn nnnnnn

[TBD] GMS-RLSP I/F OUTAGE END

YEAR = 00->99 DAY (JULIAN) = 001-> 366

nn nnn

GISAR

Ref.:

Iss./Rev.:

Date:

GIS-REQ-004-IE

2.1

12/05/2006


MF# NAME CONTENT CHARACTER TEXT TIME UTC – HRS = 00 -> 23

MINS = 00 -> 59 SECONDS = 00 -> 59

nnnnnn

[TBD] STATUS OF MANOEUVRE

0=scheduled 1=executed 2=cancelled (+ spare values up to 9)

n

[TBD] TYPE OF MANOEUVRE

0=in plane 1=out of plane 2=both (+ spare values up to 9)

n

[TBD] SAR FORWARD LINK ACTIVE DURING MANOEUVRE

0=unavailable 1=available (+ spare values up to 9)

n

[TBD] SAR RETURN LINK ACTIVE DURING MANOEUVRE

0=unavailable 1=available (+ spare values up to 9)

n

[TBD] MANOEUVRE START TIME


nn nnn nnnnnn

[TBD] MANOEUVRE END TIME


nn nnn nnnnnn

GISAR

Ref.:

Iss./Rev.:

Date:

GIS-REQ-004-IE

2.1

12/05/2006


MF# NAME CONTENT CHARACTER TEXT

[TBD] TIME OF NEW EPHEMERIS


nn nnn nnnnnn

Table 8: New or Modified Message Fields

GISAR

Ref.:

Iss./Rev.:

Date:

GIS-REQ-004-IE

2.1

12/05/2006


END OF DOCUMENT

MLT-EICD Issue 2.1 - European Space Agencyemits.sso.esa.int/emits-doc/ESTEC/20060512_GIS-REQ-004-IE_MLT-E… · RD-04 GISAR Glossary (GISGLO) Ref.: GIS-TN-005-IE RD-05 Guidelines

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