SENTINEL-1 PROPERTIES FOR GPS POD

GMV, 2019; all rights reserved

SENTINEL-1 PROPERTIES FOR

GPS POD COPERNICUS SENTINEL-1, -2 AND -3 PRECISE ORBIT DETERMINATION SERVICE

(SENTINELSPOD)

Prepared by:

13/09/2019

XM. Fernández

Project Engineer

Signed by: Marc Fernández Usón

Approved by:

13/09/2019

XJ. Aguilar

Quality Manager

Firmado por: Juan Antonio Aguilar Miguel

Authorised by:

13/09/2019

XJ. Fernández

Project Manager

Signed by: Jaime Fernández Sánchez

Document ID: GMV-GMESPOD-TN-0025

DIL Code: TD-22

Internal Code: GMV 20881/16 V5/19

Version: 1.4

Date: 16/09/2019

ESA contract number: 4000108273/13/1-NB

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SENTINELSPOD GMV 2019; all rights reserved Sentinel-1 properties for GPS POD

DOCUMENT STATUS SHEET

Version Date Pages Changes

1.0 01/04/2016 20 First version

1.1 30/03/2017 20 Update list of applicable documents (section 1.4.1).

Update all references to Sentinel-1A to Sentinel-1 to make this document applicable to both satellites.

Clarify information on Nominal Attitude Mode (section 2.1)

1.2 07/05/2018 21 Include the format of Manoeuvre history File and Outages file (section 4.3 & section 4.4)

1.3 21/01/2019 21 Update the format of the NAPEOS attitude files (section 4.1)

1.4 16/09/2019 23 Include table with acronyms (section 1.3)

Updated GPS antenna configuration (section 3.2)

Added reference to quaternions file format (section 2) and removed explicit description from section 4.

Added satellite description (section 5)

Updated list of applicable and reference documents (section 1.4)

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TABLE OF CONTENTS

1. INTRODUCTION ................................................................................................................................ 6

1.1. PURPOSE ................................................................................................................................ 6

1.2. SCOPE .................................................................................................................................... 6

1.3. DEFINITIONS AND ACRONYMS ................................................................................................. 6

1.4. APPLICABLE AND REFERENCE DOCUMENTS ............................................................................... 6 1.4.1. APPLICABLE DOCUMENTS .................................................................................................................. 6 1.4.2. REFERENCE DOCUMENTS ................................................................................................................... 7

2. SENTINEL-1 ATTITUDE CONFIGURATION ............................................................................................ 8

2.1. SENTINEL-1 NOMINAL ATTITUDE MODE .................................................................................... 8

2.2. SENTINEL-1 NOMINAL ATTITUDE LAW ...................................................................................... 9

3. NAPEOS DB CONFIGURATION .......................................................................................................... 13

3.1. CONFIGURATION OF CENTRE OF GRAVITY (COG) AND MASS OF SENTINEL-1 IN NAPEOS DB (SATELLITE.DAT) ................................................................................................................. 13

3.2. CONFIGURATION OF GPS ANTENNA COORDINATES OF SENTINEL-1 IN NAPEOS DB (TRANSP.DAT)13

3.3. CONFIGURATION OF GPS ANTENNA DIRECTION OF SENTINEL-1 IN NAPEOS DB (TRANSP.DAT) . 15

4. NAPEOS DB FORMAT SPECIFICATION ............................................................................................... 19

4.1. SENTINEL-1 MASS HISTORY FILE NAPEOS FORMAT ................................................................. 19

4.2. SENTINEL-1 MANOEUVRE HISTORY FILE NAPEOS FORMAT ....................................................... 19

4.3. SENTINEL-1 OUTAGES NAPEOS FORMAT ................................................................................. 20

5. SATELLITE DESCRIPTION ................................................................................................................ 21

5.1. SPACECRAFT GEOMETRICAL MODEL ....................................................................................... 21

5.2. THERMO OPTICAL SURFACE PROPERTIES ................................................................................ 21

5.3. NAPEOS MACRO MODEL ......................................................................................................... 22

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LIST OF TABLES

Table 1-1: Acronyms ................................................................................................................ 6

Table 1-2: Applicable Documents ............................................................................................... 6

Table 1-3: Reference Documents ............................................................................................... 7

Table 3-1: Configuration of GPS antennae parameters ................................................................ 13

Table 3-2: Corrected configuration of GPS antennae parameters .................................................. 13

Table 3-3: Euler angles describing GPS antennae orientation ....................................................... 17

Table 3-4: Rotation matrix describing GPS antennae orientation ................................................... 17

Table 3-5: Extracted Euler angles describing GPS antennae orientation ......................................... 18

Table 4-1: Mass history file format description ........................................................................... 19

Table 4-2: Manoeuvre history file format description (header) ...................................................... 19

Table 4-3: Manoeuvre history file format description (body) ......................................................... 19

Table 4-4: Outages file format description (header) .................................................................... 20

Table 4-5: Outages file format description (body) ....................................................................... 20

Table 5-1: Satellite projected area values .................................................................................. 21

Table 5-2: Sentinel-1 surface properties .................................................................................... 22

Table 5-3: Sentinel-1 Macro Model description ........................................................................... 22

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LIST OF FIGURES

Figure 2-1: Sentinel-1 Mechanical Reference Frame ...................................................................... 8

Figure 2-2: Code snippet of the combination of the two rotations for S-1 attitude ........................... 10

Figure 2-3: Code snippet of the rotation from J2000 to Zero-Doppler reference frame .................... 11

Figure 2-4: Code snippet of the rotation from Zero-Doppler reference frame to satellite body fixed reference frame ................................................................................................................ 12

Figure 3-1: Sentinel-1 deployed configuration ............................................................................ 14

Figure 3-2: Sentinel-1 stowed configuration .............................................................................. 15

Figure 3-3: GPS antennae view from -Xs ................................................................................... 16

Figure 3-4: GPS antennae view from +Ys .................................................................................. 17

Figure 5-1: Sentinel-1 drawing: deployed configuration .............................................................. 21

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1. INTRODUCTION

1.1. PURPOSE

This document describes the required information concerning Sentinel-1 in order to carry out GNSS based POD processing. In particular, the nominal attitude of the satellite, how the NAPEOS satellite and transponder DB have been created and the format of the NAPEOS internal files for attitude and mass history file are described. Unless specified otherwise, all the information contained in this document is applicable to both Sentinel-1A and -1B.

1.2. SCOPE

This document has been prepared by GMV in the frame of the Provision of the Precise Orbit Determination Service for the Sentinel missions.

1.3. DEFINITIONS AND ACRONYMS

Acronyms used in this document and needing a definition are included in the following table:

Table 1-1: Acronyms

Acronym Definition

AOC Attitude, Orbit and Control

BOL Beginning Of Life

CRF Control Reference Frame

DIL Document Item List

ESA European Space Agency

ESOC European Space Operation Centre

FOS Flight Operations System

GMES Global Monitoring for Environment and Security

GNSS Global Navigation Satellite System

GPS Global Positioning System

MACP Manoeuvre Acceleration Profile

MOL Middle Of Life

NAPEOS NAvigation Package for Earth Orbiting Satellites

ORF Orbital Reference Frame

POD Precise Orbit Determination

SAR Synthetic Aperture Radar

XML Extensible Markup Language

1.4. APPLICABLE AND REFERENCE DOCUMENTS

1.4.1. APPLICABLE DOCUMENTS

The following documents, of the exact issue shown, form part of this document to the extent specified herein. Applicable documents are those referenced in the Contract or approved by the Approval

Authority. They are referenced in this document in the form [AD.X]:

Table 1-2: Applicable Documents

Ref. Title Code Version Date

[AD.1] Sentinels POD Service File Format Specification GMES-GSEG-EOPG-FS-10-0075 1.23 16/09/2019

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1.4.2. REFERENCE DOCUMENTS

The following documents, although not part of this document, extend or clarify its contents. Reference documents are those not applicable and referenced within this document. They are referenced in this document in the form [RD.X]:

Table 1-3: Reference Documents

Ref. Title Code Version Date

[RD.1] Sentinel-1 Flight Operations Manual Volume 3 (AOC) S1-MA-TASI-SC-0006 8.0 10/09/2014

[RD.2] Flight Dynamic Databank_Release_Note S1-TN-TASI-SC-0079 8.0 27/03/2014

[RD.3] Flight Dynamic Databank FDDB_008_20140327 8.0 27/03/2014

[RD.4] Sentinel-1 AOCS Databank S1-HK-TASI-SC-0079 8.0 27/03/2014

[RD.5] Analysis of new S1 GPS antenna offset values GMV-GMESPOD-MEM-0024 1.0 19/02/2017

[RD.6] S1 Satellite characteristics N/A 1.0 N/A

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2. SENTINEL-1 ATTITUDE CONFIGURATION

Sentinel-1 provides the attitude of the satellite in the SAR annotation packages (L0 binary data). The information provided is time tagged quaternions defining the rotation between Zero Doppler and the attitude of the satellite. They are decoded into a quaternions file. Its format is described in [AD.1].

2.1. SENTINEL-1 NOMINAL ATTITUDE MODE

The Mechanical Axes are defined as (see section 1.4.15 of [RD.1]):

- The origin of the Spacecraft Mechanical Reference Frame is at the geometric centre of the circle defined by the launcher/Spacecraft interface points in the separation plane when in

stowed launch configuration - The ZS/C axis, running through the geometric centre of the spacecraft, is perpendicular to the

P/L Instrument (Antenna) radiating/observing face and positive in the direction of P/L radiation/observation

- The YS/C axis is perpendicular to the face(s) upon which the Solar Arrays are to be stowed and

positive in the direction away from the sun in the nominal operational attitude - The XS/C axis is parallel to the main axis of the SAR antenna and positive in the direction of the

spacecraft velocity vector when the spacecraft is in its nominal attitude Figure 2-1 shows these axes:

Figure 2-1: Sentinel-1 Mechanical Reference Frame

All spacecraft mechanical and geometric parameters will ultimately be referenced to this reference

system including unit positions and mass properties.

The Spacecraft Attitude Definition (described in section 1.4.14 of [RD.1]) is defined as the orientation of the spacecraft Control Reference Frame (CRF) with respect to the Orbital Reference Frame (ORF).

When the two reference frame are not aligned the yaw, roll, and pitch angles are defined as the

sequence of three rotations (classical Euler 3-1-2 sequence) required to move from the orbital reference frame to the Control Reference Frame.

The definition of the Orbital Reference Frame (ORF) will vary according to the satellite mode:

- In Nominal Mission Mode, also referred to as Normal Pointing Mode, and in Orbit Control Mode the orbital reference frame will be aligned with the Zero Doppler Orbital Reference Frame (section 1.4.8 of [RD.1])

- In all the other satellite modes the orbital reference frame will be aligned with the Local Velocity Orbital Reference Frame (section 1.4.8 of [RD.1]).

In a Nominal Mission Mode, the Spacecraft Attitude is defined as the rotation between the Zero

Doppler Reference Frame and the Control Reference Frame.

The Control Reference Frame (XCRF, YCRF, ZCRF) of Sentinel-1 is defined as (see section 1.4.11 in [RD.1]):

- The origin of the frame is the Spacecraft centre of mass

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- The orthogonal axes XCRF, YCRF, ZCRF, parallel to the Spacecraft Body Fixed Reference Frame

(XSG, YSG and ZSG)

Where the Spacecraft Body Fixed Reference Frame is defined as (see section 1.4.10 in [RD.1]):

- The origin of the frame is the Spacecraft centre of mass - the orthogonal axes XSG, YSG and ZSG, parallel to the Spacecraft Reference Frame (XSC, YSC,

ZSC)

Where the Spacecraft Reference Frame is defined as (see section 1.4.9 in [RD.1]):

- The origin is at the geometric centre of the circle defined by the launcher/Spacecraft interface

points in the separation plane when in stowed launch configuration. - The XSC axis corresponds to the flight direction in deployed configuration. - The YSC and ZSC axes are defined according to the Spacecraft configuration and form a right-

handed orthogonal coordinate system

Therefore the Control Reference Frame is defined as:

- The origin of the frame is the Spacecraft centre of mass - The XCRF axis is parallel to the main axis of the SAR antenna and positive in the direction of the

spacecraft velocity vector when the spacecraft is in its nominal attitude - The YCRF axis is perpendicular to the face(s) upon which the Solar Arrays are to be stowed and

positive in the direction away from the sun in the nominal operational attitude - The ZCRF axis, running through the geometric centre of the spacecraft, is perpendicular to the

P/L Instrument (Antenna) radiating/observing face and positive in the direction of P/L radiation/observation

The Zero Doppler Reference Frame is described in section 1.4.8 of [RD.1] (no details are provided here)

Summarizing the attitude provided by the SAR annotation file is the rotation (Roll Steering law described in section 1.4.14 of [RD.1]) between the Zero Doppler Reference Frame (R', T', L') and Control Reference Frame (CoG + Mechanical Axes).

2.2. SENTINEL-1 NOMINAL ATTITUDE LAW

In order to implement the previously described attitude mode of Sentinel-1, the following algorithms are needed, according to [RD.1]. The attitude of Sentinel-1A expressed in J2000 reference frame is composed of two rotations:

- Rotation from J2000 to the Zero-Doppler reference Frame as described in section 1.4.8 of

[RD.1]. - Rotation (around X axis, roll rotation) from the Zero-Doppler reference frame to the Satellite

Body Fixed Reference Frame as described in section 1.4.14 of [RD.1].

Note that the attitude quaternions provided as part of the L0 SAR annotation products correspond to the second rotation, being the first one not included in the L0 data.

For convenience, the following figures show code snippets in Fortran 90 of the implementation of both rotations.

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Figure 2-2: Code snippet of the combination of the two rotations for S-1 attitude

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Figure 2-3: Code snippet of the rotation from J2000 to Zero-Doppler reference frame

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Figure 2-4: Code snippet of the rotation from Zero-Doppler reference frame to satellite body fixed reference frame

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3. NAPEOS DB CONFIGURATION

3.1. CONFIGURATION OF CENTRE OF GRAVITY (COG) AND MASS OF

SENTINEL-1 IN NAPEOS DB (SATELLITE.DAT)

The mass and location of the CoG at BOL in deployed configuration of Sentinel-1 is provided in [RD.3]

with the following values:

Mass: 2159.6 kg

CoGX: +0.0035 m

CoGY: -0.0084 m

CoGZ: +2.0163 m

These values agree with the definition of the Mechanical Axes, and therefore are configured as such in

the file satellite.dat in NAPEOS database file.

The corresponding MOL values of the CoG provided in [RD.3] are:

CoGX: +0.0036 m

CoGY: -0.0087 m

CoGZ: +2.0492 m

In any case, the mass and location of the CoG are configured in the NAPEOS file satellite.dat are given by a variable input file (mass history file), provided as input from the Sentinel-1 FOS.

3.2. CONFIGURATION OF GPS ANTENNA COORDINATES OF SENTINEL-1 IN NAPEOS DB (TRANSP.DAT)

There are two sources for the location of the GPS Antennas. [RD.1] provides initial values coming from the design of the satellite. [RD.2] and [RD.3] provides the updated values just before the launch of the satellite.

In [RD.2] (page 20) and [RD.3] the values provided are:

Table 3-1: Configuration of GPS antennae parameters

X (mm) Y (mm) Z (mm)

Antenna 1 -976.182 286.860 124.092

Antenna 2 -985.471 513.465 229.276

The values in Table 3-1 are the ones used operationally by the CPOD. However, these values have proved not to accurately describe the position of the antenna phase centre and, as follows from [RD.4]

and [RD.5], new corrected value are provided in Table 3-2:

Table 3-2: Corrected configuration of GPS antennae parameters

X (mm) Y (mm) Z (mm)

Antenna 1 -937.1 332.1 131.0

Antenna 2 -946.5 558.7 236.2

The following figure shows a view of the location of the GPS antennas (extracted from [RD.1] in page 911)

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Figure 3-1: Sentinel-1 deployed configuration

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Figure 3-2: Sentinel-1 stowed configuration

3.3. CONFIGURATION OF GPS ANTENNA DIRECTION OF SENTINEL-1 IN

NAPEOS DB (TRANSP.DAT)

There are two sources for the direction of the GPS Antennas. [RD.1] provides initial values coming from the design of the satellite. [RD.2] and [RD.3] provides the updated values just before the launch of the satellite. [RD.1] does not provide any rotation matrix or Euler angles directly, but a couple of displays allow for some initial values.

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The following figure, extracted from [RD.1] in page 54, shows that the antennas are rotated around

24.39+180 degrees around X axis; the 180 degrees are needed to point the antennas in the –Z direction.

Figure 3-3: GPS antennae view from -Xs

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The following figure, extracted from [RD.1] in page 55, shows that the antennas are rotated around 14.64 degrees around +Y axis.

Figure 3-4: GPS antennae view from +Ys

Therefore the direction of the antenna is provided by the following set of rotations:

Table 3-3: Euler angles describing GPS antennae orientation

Rotation from Mechanical Axis to antenna direction

Roll (X axis) 24.39+180 = 204.39 deg

Pitch (Y axis) 14.64 deg

Yaw (Z axis) 0 deg

[RD.2] and [RD.3] provides a rotation matrix to describe the orientation of the antenna. The values

are the following (page 21 in [RD.2]):

Table 3-4: Rotation matrix describing GPS antennae orientation

GPS-A

0.972133 0.130307 -0.194879

0.037156 -0.906422 -0.420736

-0.231467 0.401771 -0.886004

GPS-B

0.972133 0.130307 -0.194879

0.037156 -0.906422 -0.420736

-0.231467 0.401771 -0.886004

These rotation matrixes can be converted to Euler Angles with the following formulas (convention 321):

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Yaw = atan2(rot(1,2),rot(1,1))

Pitch = asin(-rot(1,3)) Roll = atan2(rot(2,3),rot(3,3)) Where the convention of atan2 here is atan2(y,x) Which these formulas the Euler Angles are:

Table 3-5: Extracted Euler angles describing GPS antennae orientation

Direct Rotation Matrix

GPS-A GPS-B

Roll -154.5984 -154.5984

Pitch 11.2377 11.2377

Yaw 7.6346 7.6346

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4. NAPEOS DB FORMAT SPECIFICATION

4.1. SENTINEL-1 MASS HISTORY FILE NAPEOS FORMAT

Sentinel-1 FOS provides the mass and centre of gravity evolution in an XML format. This information is converted into a NAPEOS file with the following format:

Table 4-1: Mass history file format description

Key Type Description

Year Integer,i4 Year

Month Integer,i2 Month

Day Integer,i2 Day

Hour Integer,i2 Hour

Minute Integer,i2 Minute

Seconds Real, f6.3 Seconds

Mass Real, f9.3 Mass of the satellite (kg)

CoG_x Real, f8.5 Location of the x component of the CoG with respect to the Mechanical Axis (meters)

CoG_y Real, f8.5 Location of the y component of the CoG with respect to the Mechanical Axis (meters)

CoG_z Real, f8.5 Location of the z component of the CoG with respect to the Mechanical Axis (meters)

Example:

2014 1 1 0 0 0.000 2158.777 0.00400 -0.00900 2.00500

2014 4 14 9 0 0.000 2158.777 0.00400 -0.00900 2.00500

2014 5 26 9 0 0.000 2157.461 0.00400 -0.00900 2.00600

2014 6 10 10 0 0.000 2157.025 0.00400 -0.00900 2.00600

4.2. SENTINEL-1 MANOEUVRE HISTORY FILE NAPEOS FORMAT

Sentinel-1 FOS provides the manoeuvre acceleration profile (MACP) files with the following format:

Table 4-2: Manoeuvre history file format description (header)


Epoch Epoch File last update epoch as YYYY/MM/DD-HH:MM:SS.SSS

ESOC ID Integer,i3 Satellite ESOC ID (264 for S1A and 265 for S1B)

Table 4-3: Manoeuvre history file format description (body)


Epoch Epoch Burn start or stop time as YYYY/MM/DD-HH:MM:SS.SSS

Acceleration Real, f15.8 First component of acceleration in km/s2

Acceleration Real, f15.8 Second component of acceleration in km/s2

Acceleration Real, f15.8 Third component of acceleration in km/s2

Manoeuvre Integer, i1 Record flag. If >0, this is a manoeuvre start record. If 0, it is a manoeuvre end

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start-end flag record.

On a start record:

- value 1 indicates that the components are radial, along-track and cross-track respectively

- value 2 that they are along the J2000.0 X-, Y- and Z- axes respectively

Example:

2018/04/11-10:00:03.026 265

2016/04/29-07:25:31.282 -0.62906997D-08 0.89614348D-10-0.50554106D-06 1

2016/04/29-07:27:12.407 -0.62906997D-08 0.89614348D-10-0.50554106D-06 0

2016/04/29-15:39:26.552 -0.63265823D-08-0.21231811D-08-0.50738033D-06 1

2016/04/29-15:41:07.552 -0.63265823D-08-0.21231811D-08-0.50738033D-06 0

4.3. SENTINEL-1 OUTAGES NAPEOS FORMAT

The outages file is computed based on the existing gaps in the GPS L0 inputs combined with the manoeuvre file information. This information is converted into a NAPEOS file with the following

format:

Table 4-4: Outages file format description (header)


Epoch Epoch File last update epoch as YYYY/MM/DD-HH:MM:SS.SSS

File Title String, a12 OUTAGES FILE

ESOC ID Integer,i3 Satellite ESOC ID (264 for S1A and 265 for S1B)

Table 4-5: Outages file format description (body)


Epoch Epoch Outage start epoch as YYYY/MM/DD-HH:MM:SS.SSS

Epoch Epoch Outage end epoch as YYYY/MM/DD-HH:MM:SS.SSS

Outage type

String, a3 Type of outage. It may be: input gap (GAP), manoeuvre (MAN) or a combination of both (MIX)

Example:

2018/04/18-03:10:06.000 OUTAGES FILE 265

2000/01/01-00:00:00.000 2016/04/27-04:43:04.000 GAP

2016/04/28-16:44:34.000 2016/04/29-10:44:14.000 GAP

2016/04/29-15:39:26.000 2016/04/29-15:41:07.000 MAN

2016/05/03-12:51:38.000 2016/05/03-12:53:19.000 MAN

2016/05/05-15:03:47.000 2016/05/06-07:55:35.000 GAP

2016/05/09-14:36:29.000 2016/05/09-23:59:59.000 MIX

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5. SATELLITE DESCRIPTION

5.1. SPACECRAFT GEOMETRICAL MODEL

Figure 5-1: Sentinel-1 drawing: deployed configuration

The figure extracted from [RD.6] shows the overall satellite and solar array dimensions.

The resulting projected areas are summarized in the following table (from [RD.6]):

Table 5-1: Satellite projected area values

Component Projected area [m2]

Along-track frontal area at 0 deg Yaw Steering 5.57

Along-track frontal area at -3.9 deg Yaw Steering 6.12

Along-track frontal area at 3.9 deg Yaw Steering 8.15

Along-track frontal area averaged over one orbit 6.35

Solar Array frontal area 15.5

SAR antenna frontal area 12.55

5.2. THERMO OPTICAL SURFACE PROPERTIES

The following table lists the spacecraft surface properties (from [RD.6]):

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Table 5-2: Sentinel-1 surface properties

Surface Infrared emissivity [-] Solar absorptivity [-]

SAW – Frontal Side (BOL) 0.81 0.91

SAW – Frontal Side (EOL) 0.81 0.91

SAW – Rear Side (BOL) 0.82 0.92

SAW – Rear Side (EOL) 0.82 0.92

SAR – Frontal Side (BOL) 0.85 0.19

SAR – Frontal Side (EOL) 0.85 0.47

SAR – Rear Side (BOL) 0.76 0.44

SAR – Rear Side (EOL) 0.76 0.65

Platform - Radiators (BOL) 0.77 0.14

Platform - Radiators (EOL) 0.77 0.21

Platform – MLI (BOL) 0.65 0.45

Platform – MLI (EOL) 0.65 0.60

5.3. NAPEOS MACRO MODEL

Based on the information presented above, a macro model representing the Sentinel-1 satellite geometry is obtained. The macro model used at the CPOD Service is presented in Table 5-3.

For the computation of the values shown below, the total areas and effective thermo-optical properties have been obtained by adding the different contributions along each of the specified directions. The information not available in [RD.6] has been inherited from similar missions.

Table 5-3: Sentinel-1 Macro Model description

Panel #

1 (

x+

)

Panel #

2 (

x-)

Panel #

3 (

y+

)

Panel #

4 (

y-)

Panel #

5 S

AR (

z+

)

Panel #

6 S

AR (

z-)

Panel #

7:

Sola

r

Arr

ay F

ront

Panel #

8:

Sola

r

Arr

ay B

ack

Area [m2] 5.57 5.57 6.79 6.79 12.55 12.55 34.456 34.456

Visual specular ref. [-] 0.64 0.64 0.64 0.64 0.81 0.56 0.09 0.08

Visual diffuse ref. [-] 0.06 0.06 0.06 0.06 0.00 0.00 0.00 0.00

Visual absorption [-] 0.30 0.30 0.30 0.30 0.19 0.44 0.91 0.92

Infrared specular ref. [-] 0.225 0.225 0.225 0.225 0.08 0.12 0.19 0.00

Infrared diffuse ref. [-] 0.065 0.065 0.065 0.065 0.07 0.12 0.00 0.18

Infrared absorption [-] 0.71 0.71 0.71 0.71 0.85 0.76 0.81 0.82

Code:

Date:

Version:

ESA contract:

Page:

GMV-GMESPOD-TN-0025

16/09/2019

1.4

4000108273/13/1-NB

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