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Mars Premier MAMBO
Réf. : MARS-TS-MAMBO-001-CNESEd. : 12 Date : March 820, 2002Rév. : 0 Page : 1
Direction des Systèmes OrbitauxSous-Direction Etudes Systèmes et DéveloppementsDivision Mars Premier
MAMBO INSTRUMENT PRELIMINARY
TECHNICAL REQUIREMENTS
Nom et Fonction Date Signature
Préparé par
Jean-Pierre ESCARNOT DSO/ED/MA/OB Gérard BEAUDIN Observatoire de Paris
Approuvé par Thien LAM-TRONG DSO/ED/MA/OB/DJean-Louis COUNIL
DPI/E2U
Autorisé par Christian CAZAUX DSO/ED/MA/D Richard BONNEVILLE DPI/E2U/D
CENTRE NATIONAL D'ETUDES SPATIALES
S i è g e2 place Maurice Quentin - 75039 Paris Cedex 01
Tél. : 01 44 76 75 00 / Téléfax 01 44 76 76 76 / Télex 214674
Centre de Toulouse18, avenue Edouard Belin - 31401 Toulouse Cedex 4Tél. : 05 61 27 31 31 / Téléfax : 05 61 28 13 27 / Télex : 531081
RCS PARIS B 775 665 912 - SIRET 775 665 912 000 82 / CODE APE 731ZN° d'identification TVA : FR 49 775 665 912
Data Base Index
CONFIDENTIALITY : KEY WORDS :
TITLE : MAMBO INSTRUMENT REQUIREMENTS DOCUMENT
AUTHOR :
ABSTRACT
Functional, performance, operational and design requirements of the MAMBO Instrument
DOCUMENT STATUS :
Volume : total no.of pages : 4548
No. of introductory pages : 4
No. ofAppendices: 0 Language : GB
Controlled Document : NON As of : Cognizant :
HOST COMPUTER and SOFTWARE : PC - WORD 7
DIFFUSION INTERNE
Nom Sigle Bpi EX
EQUIPE PROJETC. CAZAUX DSO/ED/MA/D 2222 1
T. LAM-TRONG DSO/ED/MA/OB 2222 1R. CLEDASSOU DSO/ED/MA/OB 2222 1JP. ESCARNOT DSO/ED/MA/OB 2222 1JR. MEYER DSO/ED/MA/OB 2222 1E. HINGLAIS DTS/AE/MTE/IN 2222 1
JB. DUBOIS DSO/ED/MA/SY 2222 1P. DUCHON DSO/ED/MA/SY 2222L. KERJEAN DSO/ED/MA/SY 2222B. LABORDE DSO/ED/MA/SY 2222 1Ph. PACHOLCZYK DSO/ED/MA/SY 2222
M. WILSON DSO/ED/MA 2222
SUPPORTS PROJETN. GEAY-KAMINSKI DTS/AQ/QP/SC 2222 1R. NAUCODI DSO/SG/CS 2222 1A. MOGNETTIC. ROUANNE SG/DAF/AC/SE 1605 1
DIRECTION DES PROGRAMMESR. BONNEVILLE DPI/E2U 1F. ROCARD DPI/E2U 1JL. COUNIL DPI/E2U 2903 1
DIFFUSION EXTERNE
Nom EX
OBSERVATOIRE DE PARIS-LMD / EQUIPE PROJETF. FORGETG. LMD/PIOP/ 11
BEAUDIN LERMA/DTG. BEAUDINA. DESCHAMPS
OP/LERMA/DTOP/LERMA
11
A. DESCHAMPSB. GERMAIN
OP/LERMASEGIME
11
B. GERMAINF. GADEA SEGIMEOP/LERMA
11
F. GADEAM. GHEUDIN
OP/LERMAOP/LERMA
11
M. GHEUDINJ.M. KRIEG
OP/LERMAOP/LERMA
1
J.M. KRIEGJ.M. LAMARRE
OP/LERMAOP/LERMA/D
J.M. LAMARREB. THOMAS
OP/LERMA/DOP/LERMA(Th)
B. THOMASA.. SEMERY
OP/LERMA(Th)OP/LESIA
A.. SEMERYM. BOUYE OP/LESIAOP/LESIA
1
M. BOUYE OP/LESIA 1P. RICAUDF. FORGET OBS.
BDXLMD/PI11
ASTRIUM 1ASPI 1
Change History
Issue Version Date Modified Pages Approval1 0 March 8,
2002Initial Release
2 0 March 20, 2002
all
Table of contents
1 SCOPE AND DEFINITIONS......................................................................................................1112111.1 Scope.......................................................................................................................................................111211
1.2 Conventions...........................................................................................................................................111211
2 GENERALITIES.........................................................................................................................1213122.1 SCIENTIFIC OBJECTIVES...............................................................................................................121312
2.1.1 Specific physical objectives.............................................................................................................................1314132.1.1.1 Wind:......................................................................................................................................................1314132.1.1.2 Temperature:...........................................................................................................................................1314132.1.1.3 Water Vapour:.........................................................................................................................................1314132.1.1.4 D/H Ratio:...............................................................................................................................................1314132.1.1.5 Ozone:.....................................................................................................................................................1415142.1.1.6 Hydrogen Peroxyde (H202):....................................................................................................................1415142.1.1.7 Carbon Monoxyde:.................................................................................................................................1415142.1.1.8 Surface Science:......................................................................................................................................141514
2.1.2 Global objectives.............................................................................................................................................1415142.1.2.1 Atmospheric dynamics and comparative meteorology:..........................................................................1415142.1.2.2 Water cycle:............................................................................................................................................1516152.1.2.3 A global view of Martian atmosphere photo-chemistry.........................................................................151615
2.2 DESCRIPTION OF MAMBO MISSION PHASES..........................................................................161716
2.3 MAMBO Schematic Design.................................................................................................................171817
2.4 MAMBO Operating Modes Description.............................................................................................171917
2.5 MAMBO Reference Frame..................................................................................................................192119
3 INTERFACES.............................................................................................................................2022203.1 FLIGHT SYSTEM INTERFACES.....................................................................................................202220
3.2 SUB-SYSTEM INTERFACES & INTERNATIONAL DELIVERABLES.....................................202220
4 ARCHITECTURE DESIGN REQUIREMENTS......................................................................2224224.1 GENERAL.............................................................................................................................................222422
4.2 THERMO-MECHANICAL ARCHITECTURE...............................................................................2325234.2.1 Mechanical Architecture and layout................................................................................................................2325234.2.2 Thermal............................................................................................................................................................2527254.2.3 Pyrotechnics equipment..................................................................................................................................262826
4.3 ELECTRICAL ARCHITECTURE.....................................................................................................272927
4.4 DATA HANDLING..............................................................................................................................283028
5 FUNCTIONAL REQUIREMENTS FUNCTION OF MISSION PHASES.............................2931295.1 PHASE 1 : LAUNCH............................................................................................................................293129
5.2 PHASE 2 : EARTH/MARS CRUISE..................................................................................................293129
5.3 PHASE 3 : ORBITAL SCIENCE........................................................................................................3032305.3.1 Orbital science phase 1....................................................................................................................................3032305.3.2 Orbital science phase 2....................................................................................................................................303230
6 FUNCTIONAL and performance requirements........................................................................3133316.1 Front-End...............................................................................................................................................313331
6.1.1 "Cassegrain" tTelescope..................................................................................................................................3133316.1.2 Scan mechanism..............................................................................................................................................323432
6.1.3 Calibration Load..............................................................................................................................................3335336.1.4 Receiver...........................................................................................................................................................343633
6.2 Back-End................................................................................................................................................3638356.2.1 USO.................................................................................................................................................................3638356.2.2 Frequency synthesiser......................................................................................................................................3738366.2.3 IF processor.....................................................................................................................................................3739366.2.4 Spectrometer....................................................................................................................................................384137
6.3 Power and Data Control Unit.............................................................................................................4143386.3.1 DPU.................................................................................................................................................................4143386.3.2 PDU.................................................................................................................................................................424440
7 OPERATIONAL REQUIREMENTS.........................................................................................4346417.1 Life duration / Mission duration..........................................................................................................434641
7.2 Reliability...............................................................................................................................................434641
7.3 Availability.............................................................................................................................................434641
7.4 Autonomy, Observability & Commandability...................................................................................4447427.4.1 MAMBO ancillary data...................................................................................................................................444742
7.5 Programming of MAMBO instrument...............................................................................................444742
7.6 MAMBO operating modes...................................................................................................................454843
8 Development Requirements.........................................................................................................4750448.1 Assembly Integration & Tests Requirements.....................................................................................475044
List of figures and tables
Figure 2.1-1 Simulation of a limb spectrum (tangent altitude: 10km) around 320-350 GHz in typical Martian conditions for a MAMBO-like instrument.............................................................121312
Table 2.2-1 Mars Premier mission events...............................................................................161716Figure 2.3-1 Global design type of MAMBO.............................................................................171817Figure 2.4-1 Observing modes of MAMBO..............................................................................181918Figure 2.4-2 Summary of the geometry of limb scanning for the various orbits defined in the CNES
AO....................................................................................................................................192119Figure 3.2-1: MAMBO Flight System interfaces description....................................................202220Figure 6.2.3-1 Temporary schematic drawing of the IF processor with the dual channel receiver.
..........................................................................................................................................384137figure 7.6-1: example of worst-case angular rate scanning sequence.....................................454843
TBC and TBD listsTBC:
MAMBO field of view 17MAMBO mass requirement 22Back-End mass requirement 22Bio-cleaning requirement 23MAMBO power consumption requirement 27MAMBO power consumption target 27Antenna 1st side lobe requirement 32Scan mechanism reaction torque requirement 33Hot calibration load temperature accuracy requirement 343Receiver thermal stability requirement 35Calibration data cycles 354USO long term stability requirement 365USO short term stability requirement 36USO phase noise requirement 365Receiver two-points calibration requirement 35Integration time 35Calibration cycles 35IFP schematic drawing 387Spectrometers design (CTS ; resolution) requirement 398Spectrometers design (central frequency) requirement 398Spectrometers design (DAC ; resolution) requirement 39Spectrometers design (DAC ; bandwidth) requirement 398DPU mass memory requirement 3941
TBD:Number of large filters 12Industrial partners (2) 21Safety rules requirement 26Back-End power consumption requirement 27Cruise phase power status requirement (2) 29Scan mechanism rotation linearity requirement 332Receiver gain calibration requirement 33Receiver gain stability requirement 34Receiver gain ripple requirement 34Receiver channel requirement 35Weighting function 35Calibration integration time 35Calibration periodicity requirement 364USO phase noise requirement 35
Weighting function 3 5IFP design (detection and digitalisation) requirement 376IFP spectral calibration requirement 36
IFP spectral lines requirement 376Spectrometers design (AC ; bandwidth) 38Spectrometers design 39Spectrometers : mass, volume, power 408DPU telemetry requirement 4139PDU power supply design requirement 420MAMBO operating modes requirement 45Nadir integration time 45
Signal to noise ratio 453
Glossary
ACS Attitude Control SystemAIT Assembly Integration & TestsATCT Attitude and Trajectory Control ThrustersBE MAMBO Back-EndCDR Critical Design ReviewCoG Centre of GravityCNES Centre National d’Etudes SpatialesDOD Depth Of DischargeDSN Deep Space NetworkDSGS Deep Space Ground StationsFE MAMBO Front-EndGSE Ground Support EquipmentHGA High Gain AntennaICD Interface Control DocumentIRD Interface Requirements DocumentJPL Jet Propulsion LaboratoryLGA Low Gain AntennaMCM Mars to Earth Cruise ManoeuvreMOI Mars Orbit InsertionNASA National Aeronautics and Space AdministrationOD Orbit DeterminationOP Observatoire de ParisOS Orbiting SamplePDCU Power Data Control UnitPDR Preliminary Design ReviewPOMS Probability Of Mission SuccessRAMS Reliability, Accessibility, Maintainability and SafetyRDV RendezvousRSC RDV Sample & CaptureSRR System Requirements ReviewTT&C Tracking, Telemetry & CommandUSO Ultra Stable Oscillator
Applicable Documents
AD1 Announcement of Opportunity (AO): http://smsc.cnes.fr/PREMIER-2007/
AD3 Product Assurance specification: MARS-PA-MSRO-027-CNES.
AD6 2007 Orbiter / scientific payloads interface requirements: MARS-IF-MSRO-002-CNES. .
AD7 "2005 mission" Planetary protection specification: MARS-PA-MSRO-025-CNES.
AD3: applicable specifications to this document are also to be applied.AD7: for bio-cleaning procedures only.
Reference Documents
None
1 SCOPE AND DEFINITIONS
1.1 Scope
This document contains the requirements applicable to the Mars Atmosphere Microwave Brightness Observer Instrument Flight System also called in the document : MAMBO.
1.2 Conventions
Requirements numbering :
The MAMBO requirements are written inside frames. They are designated by a number with the following format : MAMB-X-N with :
MAMB recall the level of the requirement (MAMB for MAMBO Instrument)
X is a letter among :
R for Requirement,
T for target,
N is the number of the requirement itself for the considered chapter.
The requirements corresponding to the letter R shall be fulfilled and demonstrated by the contractor.
The requirements corresponding to the letter T are not mandatory to be fulfilled (whatever the reason for this: difficulty to demonstrate costs risks, state of the art). For these requirements the contractor shall document the work and the trade-off performed.
When not specified, accuracy requirements are intended to be 3-sigma standard deviations.
GENERALITIES
1.3 SCIENTIFIC OBJECTIVESThe microwave sounder MAMBO aims to characterize the dynamics and the composition of the Martian atmosphere, with an unprecedented sensitivity. For this purpose, MAMBO will analyse the thermal emission of the atmosphere at microwave frequencies using heterodyne spectroscopy, for the first time from orbit around another planet. In practice, MAMBO will perform measurements at the atmospheric limb and at nadir using a receiver dedicated to the monitoring of selected lines of key molecules in the range 320-350 GHz:
• CO at 345.796 GHz • 13CO at 330.588 GHz• H2O at 325.153 GHz• HDO at 335.395 GHz• O3 at 326.901 GHz• H2O2 at 326.981 GHz
A number (1 or 2 TBD) of large filters will be dedicated to the measurement of the Mars surface continuum.
Figure 2.1-1 Simulation of a limb spectrum (tangent altitude: 10km) around 320-350 GHz in typical Martian conditions for a MAMBO-like instrument.
1.3.1 Specific physical objectivesThe instrument performances will allow the 3D mapping, with an excellent spatial cover, of the following physical items:
1.3.1.1 Wind:
Our proper experience using atmospheric models and performing data assimilation into models when referring only to temperature data has shown how difficult it is to determine the circulation of the mid and high atmosphere without accurate spectrometric measurements. The MAMBO high spatial resolution allows to make use of the line profiles and their Doppler shift. Limb viewing allows a direct measurement of the winds on Mars from orbit. Both 13CO and CO will be used to monitor the atmosphere from 20 km to 130 km, with a vertical resolution better than 10 km and an 10 m.s-1-accuracy. Such a measurement will provide key information on the atmospheric dynamics.
1.3.1.2 Temperature:
From the planet surface up to 120 km. The temperature profile will be retrieved from CO and 13CO lines. For temperature, as well as for the other atmospheric characteristics, the inversion using millimeter spectra is simplified because of the four following factors:
1) the non sensitivity of the targeted molecules to the aerosol . For instance, this is a crucial issue in the infrared below 30 km.
2) the accurate knowledge of the line profiles and of the spectrometric parameters. 3) the linearity with temperature of the thermal emission.4) the validity of the Local Thermal Equilibrium assumption. For example, non-LTE processes are a
major problem in the IR above 60 km. This will allow an unprecedented accuracy, especially during periods when the atmosphere is dust laden.
1.3.1.3 Water Vapour:
Using the H2O and HDO lines will allow measuring water vapour profiles from near the surface up to 60 km, with an accuracy and a sensitivity much better than previous experiments. The profile will be determined even when and where the atmosphere is at the driest. There again, the millimetre lines insensitivity to aerosols is a key advantage for observations and interpretations.
1.3.1.4 D/H Ratio:
This isotopic ratio will be obtained by simultaneous spectroscopy of H2O and HDO. Monitoring D/H ratio is a key investigation to understand the evolution of water on Mars. Its current estimation remains highly uncertain. Fractionation due to condensation processes in the atmosphere may induce spatial (vertically, in particular) and seasonal variations full of information about the current and past climates on Mars. For instance, it has been suggested that the water vapour originating directly from the permanent northern polar cap may exhibit a D/H ratio different than the main atmospheric value. Therefore, mapping D/H ratio on Mars will be of high interest to understand chemical and dynamical atmospheric processes.
1.3.1.5 Ozone:
Ozone profile will be measured accurately up to 70 km, simultaneously with water vapour. This will allow us to better understand the relationship between the two species. Ozone and Water vapour are supposed to anti-correlated. Before MAMBO, the observation of ozone from Mars orbit will have only been done by the SPICAM instrument aboard Mars-Express by solar occultation, therefore with a very weak spatial coverage (a few profiles).
1.3.1.6 Hydrogen Peroxyde (H202):
This species has never been observed on Mars, yet. Several models have shown its key importance for the photo-chemistry of the Martian atmosphere (control of H2, O2 and CO) and for its role in oxydizing the Martian soil, a key issue for exobiology. The sensitivity of the limb observations should allow MAMBO to profile H202 even for the lowest density estimate.
1.3.1.7 Carbon Monoxyde:
The observation of the strong 12CO line simultaneously with the weaker 13CO line will allow to estimate CO vertical profile with an accuracy of 10-15% up to 90 km in limb viewing.
1.3.1.8 Surface Science:
MAMBO shall include a continuum channel able to measure the surface brightness temperature. This measured brightness temperature Tb (Tb=T) differs from the skin surface kinetic temperature because 1) the emissivity can be significantly lower than unity and 2) the temperature T sensed in the microwave range reflects the vertically integrated physical temperature of the subsurface as weighted by the absorption coefficient of the regolith or ice material, within the top centimeter layer (for dry soil or a narrower layer if ice is present) of the Mars surface. Careful analysis of the brightness temperature will thus allow the mapping of the variations of surface emissivity and possibly the thermal inertia of the subsurface. Like on Earth, it might be possible to learn more about the ground properties (roughness, physical properties) by comparing the surface emission observed in horizontal and vertical polarization using a double receiver (see below design description section).
1.3.2 Global objectivesThe combination of these measurements allow to reach the following global objectives:
1.3.2.1 Atmospheric dynamics and comparative meteorology:
The simultaneous knowledge of the zonal wind and of the thermal structure of the atmosphere combined with state-of-the-art techniques of data assimilation in General Circulation Models will allow us to determine the 3D atmospheric circulation day after day. Synergy between observations from orbit and ground-based meteorological observations (ATMIS on Netlander) is especially interesting within this context.
1.3.2.2 Water cycle:
In combination with the observation of the General Circulation, the 3D mapping of water vapour should allow us to characterize water vapour transport by the atmosphere and locate its sources and sinks.
1.3.2.3 A global view of Martian atmosphere photo-chemistry
H2O, O3, H2O2 and CO are key species for the photochemical equilibrium of the Martian atmosphere and its interaction with the surface. The observations of the temporal and spatial variations of these species will be interpreted in light of a 3D photochemical model, allowing a true understanding of the processes involved and their coupling.
1.4 DESCRIPTION OF MAMBO MISSION PHASESThe key mission steps of the entire Mars Premier are listed below:
Event Date or Duration
Launch September 2007
NetLander deployment Between June & August 2008
Mars Arrival Between mid-July and mid-September 2008
Beginning of NetLander relay mission
Two weeks after Mars Arrival
MAMBO and other instruments operations
From commissioning (Mars arrival) and mostly after Netlander operations until end of mission
End of nominal mission Three terrestrial years after Mars arrival
End of extended mission Four terrestrial years after Mars arrival
Table 2.2-1 Mars Premier mission events.
The MARS PREMIER Announcement of Opportunity (AO) shall be applied, as a reference, for MAMBO mission phases (AD1).
1.5 MAMBO Schematic Design
The following schematic gives an example of the expected overall design of MAMBO.
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Figure 2.3-1 Global design type of MAMBONote: As this design evolved, for consistency purpose,As indicated in the upper figure above, the input bandwidth shall be at least 3223-3498 GHz in accordance with bandwidth of figure 3.2-1 and MAMB-R-620.
The Bback-Eend electronics (e.g. IF processor, spectrometers, DPU) could be put in an electronic box separate from the main Ffront- Eend box (sScan mechanism, antenna, Front- Eend)
1.6 MAMBO Operating Modes DescriptionWhen MAMBO is fully operating (beside OFF, stand-by, TM/TC modes), MAMBO will combine several modes of observation in which be operated in four main modes. MAMBO antenna will alternately look at:
1. One or several points between Nadir and Nadir±70° (integration time per point: 1 – 5 s)Note : in present IRD (AD6) between MAMBO and 2007 Orbiter NADIR ±45° is a forbidden field of view (TBC).2. The limb on one side (see details below)3. The cold calibration target (cold sky above the limb)4. The internal calibration hot load
MAMBO will repeat the same operations on the other side (modes baseline) or on the same side (in some specific operating modes).
Figure 2.4-1 Observing modes of MAMBO.
The observing strategy at the limb is a key issue. A few inputs regarding the limb strategy are: MAMBO antenna will rotate preferentially step by step. A constant angular rate would be
considered if it is shown to strongly simplify design considerations. MAMBO will acquire one spectrum every 5 km (limb vertical projection). The angular rate of the antenna will be suited to a limb scanning velocity of 3 2 km/s. The
corresponding angular rotation rates is given in the table below. Limb scanning shall be performed in the range 0 km to 12010 km. Margins are required on both
sides of this scale depending on the strategy fostered to identify the limb / surface border on the basis of the information provided by the orbiter main CPU and/or from the detection of the limb by the instrument itself.
Orbiter mission phases Oph2b Oph2a Oph1 Oph2bOrbiter altitude (km) H 170.0 350.0 500.0 1000.0Orbiter velocity (km/s) V 3.47 3.39 3.32 3.12Distance Orbiter-limb at 0 km (km) D (0) 1086 1579 1907 2789Distance Orbiter-limb at 130 km (km) D(130) 527. 1252. 1641. 2601Pointing angle () to the surface 72.2 65.0 60.6 50.6Limb (0-130 km) apparent angle () 9.2 5.2 4.2 2.8Limb scanning rate during limb scanning (km/s)
dz/dt 3 2 3 2 3 2 3 2
Antenna mean rotation rate during Limb scanning (°/s)
d/dt 0.21 0.14
0.12 0.08
0.10 0.06
0.06 0.04
Figure 2.4-2 Summary of the geometry of limb scanning for the various orbits considered defined in the CNES AO, associated to the following table (2.5). with table illustrating the possible range
of rotation rate for the antenna during limb scanning.
1.7 MAMBO Reference Frame
MAMB-R-0010 The MAMBO reference frames shall be taken according to the definitions given in AD6.
2 INTERFACES
2.1 FLIGHT SYSTEM INTERFACESThe MAMBO interface with the Mars Premier Orbiter is preliminary defined in the scientific payloads / 2007 Orbiter interface preliminary document AD 6. A MAMBO interfaces requirements document will be issued after scientific payloads selection to be done in July, 2002.
2.2 SUB-SYSTEM INTERFACES & INTERNATIONAL DELIVERABLESThe following schematic describes roughly the MAMBO interfaces.
Figure 3.2-1: MAMBO Flight System interfaces description (note that the recveiver bandwidth evolvedmoves to 322-349 GHz)
Several sub-systems have been identified to be provided by foreign partners:
The spectrometers will be provided by: Baseline plan: Chirp Transform spectrometers by Germany (MPAE) + Autocorellators by
Sweden (SSC / Omnisys)
Front-End (FE)Calibration load
Télescope
Scan mechanism
Receiver325 - 346 GHz
Back-End (BE)USO
Frequency synthesiser
I.F. Processor
Spectrometers
Power and Data Control UnitDPU PDU
Bus 1553 22 -37 V DCHLC
SecondarydistributionTM / TC
Backup plan: Spectrometers sub-contracted to industrial partners TBD (suggestion : Omnisys company in Sweden).
The IF processor will be provided by: Baseline plan: IF processor and Frequency synthesiser by the USA (JPL) Backup plan: IF processor and Frequency synthesiser sub-contracted to industrial
partners TBD (suggestion : Omnisys company in Sweden).
The choice of baseline or backup plan depends on the funding by the foreign space agency.The interface between MAMBO sub-systems to be supplied by partners and/or contractors shall be defined in a specific IRD, to be also issued after scientific payload selection.
3 ARCHITECTURE DESIGN REQUIREMENTS
3.1 GENERAL
MAMB-R-0020 MAMBO Mass requirement
The total mass of the MAMBO INSTRUMENT, including 20% margin (AD6) shall be less than 25 kg TBC(This value includes 1 kg TBC for the harness mass)
MAMB-R-0030 Back-End mass requirement
NONE (TBC).
MAMB-R-0040 Environment
MAMBO shall withstand the environment defined in AD6 during each phase of the mission.
MAMB-R-0050 Margin definition
All the margins in each domain (mechanical, thermal, electrical…) shall be clearly identified and justified. These margins shall be permanently traceable.
MAMB-R-0060 Margin summation
The method to sum margins shall be explained and justified, stacking of margins shall be avoided
MAMB-R-0070 Design-to-cost
The design of MAMBO shall consider a design-to-cost approach. When possible, the equipment shall be off-the-shelf.
MAMB-R-0080 Bio-cleaning (TBC)
Any MAMBO equipment shall be compliant with a method of external surfaces bio-cleaning defined in AD 7. In particular the general mechanical architecture and the layout shall be compliant with the need of cleaning the exposed surfaces.
3.2 THERMO-MECHANICAL ARCHITECTURE
3.2.1 Mechanical Architecture and layout
MAMB-R-0090 Mechanical design rules
The Mechanical Design Rules shall be defined and presented to OP /CNES. After approval by OP/CNES, they shall be applied for the complete instrument. They shall be compliant with AD 6.
The qualification margin factor with respect to specified loads (flight limit level) shall be 1.25 for quasi-static and sine loads and 4 dB for random & acoustic loads,
The design margin (in the general case) with respect to the qualification loads shall be 1.1 for yield and 1.25 for rupture loads.
MAMB-R-0100 Avoid over design
The process leading to the static, sine and random requirements at the sub-system and equipment level shall minimise their levels. Tailored interface force limiting criteria shall be identified whenever possible.
MAMB-R-0110 Mathematical Mechanical Models
The CAD drawings shall be delivered to OP/CNES in a CATIA format. If not possible, the exchange data protocol will be STEP AP203. The finite element "modelisations" shall be delivered to OP/CNES in a NASTRAN V70 format.
MAMB-R-0120 Integrity
The design of the structure shall guarantee the integrity of the MAMBO instrument in each phase of the mission, and be consistent with the Orbiter requirements.
MAMB-R-0130 Fields of view
The Design and the layout of MAMBO shall be compliant with the different radio-electrical fields of view defined in AD6.
MAMB-R-0140 Out-gassing
MAMBO shall be compliant with the outgassing rules (see AD3). An analysis shall be performed to take into account the outgassing of the equipment units on the main performances.
MAMB-R-0150 Optical and RF references
Optical and RF references shall be provided on the MAMBO for alignment control. Optical and RF references will have to be coaligned with a TBD known accuracy. This These references shall be kept accessible when the instrument is integrated.
MAMB-R-0160 Layout optimised for integration
The layout shall be optimised to simplify the integration and test of the instrument.
MAMB-R-0170 Layout optimised for bio-cleaning and maintainability
The layout shall be optimised to ease the accessibility, the cleaning for planetary protection purpose and maintainability of any equipment units.
MAMB-R-0180 Mechanisms functional margin
The § 4.7.4.3.4. and § 4.7.4.3.5. of the ECSS-E-30-part3A (Mechanical — Part 3: Mechanisms) shall be applied.
MAMB-R-0190 Mechanisms life duration
The § 4.8.3.3.11. of the ECSS-E-30-part3A (Mechanical — Part 3: Mechanisms) shall be applied.
MAMB-R-0200 Mechanisms Qualification Program
The mechanisms qualification programs shall demonstrate that they meet specifications with functional and lifetime margins (see previous requirements). The qualification program shall conclude with an expert appraisal.
3.2.2 Thermal
MAMB-R-0210 Thermal control design
The thermal control shall be designed in order to maintain all the equipment of the instrument in their specified stocking or operational temperature range depending on the phase of the mission. This design shall be compliant with AD6.
MAMB-R-0220 Thermal control Design rules
The thermal control Design Rules shall be defined and presented to OP / CNES. The nominal temperature ranges for equipment on and off shall be clearly identified. They shall be compliant with AD6.
MAMB-R-0230 Thermal control Design margin
with respect to these nominal ranges, the acceptance ranges will be defined with a 5 degrees margin and the qualification ranges with a 10 degrees margin.
MAMB-R-0240 Mathematical Thermal Models
The thermal models shall be delivered to CNES in ESATAN and ESARAD format.
MAMB-R-0250 Temperature sensors
The number and accuracy of temperature sensors shall be sufficient to allow the control of all the necessary equipment, and an update of the thermal control laws by ground in case of an out of range thermal behaviour detected in flight.
MAMB-R-0260 Temperature sensors
The choice of the thermal sensors monitored during the safe mode has to enable a complete status of the thermal conditions. The number of sensors shall be in accordance with AD6.
3.2.3 Pyrotechnics equipment
MAMB-R-0270 Safety rules
These equipment have to be compliant with the safety rules to defined by 2007 Orbiter prime contractor in phase B (TBD).
MAMB-R-0280 Pyrotechnics Design Rules
The pyrotechnics Design Rules shall be defined and presented to OP / CNES before phase B (These rules shall concern the pyrotechnic devices as well as their complete electrical chain and driver units). They shall be compliant with AD6 requirements.
3.3 ELECTRICAL ARCHITECTURE
MAMB-R-0290 MAMBO instrument power consumption
The overall MAMBO instrument power consumption shall be less than 60 W TBC. This value includes 20 W for margin and shall be compliant with AD6 requirements.
MAMB-T-0300 MAMBO instrument power consumption
The overall MAMBO instrument target power consumption is 40 W TBC. This value shall be compliant with AD6 requirements.
MAMB-R-0310 Back-End power consumption
The Back-End power consumption is TBD.
MAMB-R-0320 PDU design
The PDU shall be sized to support all primary and secondary power lines needed for all equipment units, including Back-End unit.
MAMB-R-0330 Electrical design rulesThe Electrical Design Rules shall be defined and presented to OP/CNES before phase B. They shall be compliant with AD6.
After approval, they shall applied for the complete instrument and any exception shall require a waiver approved by OP/CNES.
MAMB-R-0340 EMI/EMC rulesThe EMI/EMC Rules shall be defined and presented to OP/CNES before Phase B. After approval, they shall be applied for the complete spacecraft. They shall be compliant with AD6 and shall demonstrate the compatibility of Intermediate Frequency wrt the Orbiter X band equipment.
3.4 DATA HANDLING
MAMB-R-0350 Data Handling design
The Data Handling design shall be compliant with AD6 requirements.
4 FUNCTIONAL REQUIREMENTS FUNCTION OF MISSION PHASES
The following requirements is not an exhaustive list. During all the following phases of the mission the MAMBO instrument shall:
4.1 PHASE 1 : LAUNCH
MAMB-R-0360 launch phase power status
MAMBO instrument shall be OFF during launch phase. The thermal control shall be performed in accordance with AD6 requirements.
MAMB-R-370 launch phase mechanical configuration
MAMBO instrument shall be in the launch configuration: scan mechanism locked and antenna pointing the internal load.
4.2 PHASE 2 : EARTH/MARS CRUISE
From Ariane5 Injection to insertion around Mars.
MAMB-R-0380 Cruise phase power status
MAMBO instrument shall be “OFF” during the cruise except for (TBD) calibration and pointing operations opportunity (on celestial objects). The thermal control shall be performed in accordance with AD6 requirements.
MAMB-R-0390 Cruise phase power status
MAMBO instrument shall be "ON"operated for commissioning phase (TBD). The thermal control shall be performed in accordance with AD6 requirements.
MAMB-R-0400 Cruise mechanical configuration
MAMBO instrument shall be in the stand-by"safe" configuration: antenna pointing the internal load (excepted for commissioning and calibration/pointing operations).
4.3 PHASE 3 : ORBITAL SCIENCE
4.3.1 Orbital science phase 1
MAMB-R-0410 Power statusbudget
MAMBO shall be operated within power budget available defined in AD6(TBD). For MAMBO phase A studies half of the budget to be shared between Orbiter 2007 scientific payloads could be taken into account.
MAMB-R-0420 Phase 1 MAMBO operating sequence
MAMBO shall be operated within the observation sequence and strategy preliminary defined in § 2.4.
4.3.2 Orbital science phase 2
MAMB-R-04320 Power statusbudget
MAMBO shall be operated within power budget available (TBD) defined in AD6. For MAMBO phase A studies half of the budget to be shared between Orbiter 2007 scientific payloads could be taken into account.
MAMB-R-0440 Phase 2 MAMBO operating sequence
MAMBO shall be operated within the observation sequence and strategy preliminary defined in § 2.4.
5 FUNCTIONAL AND PERFORMANCE REQUIREMENTS
According to MAMBO general configuration presented in figure 3.1 the following requirements shall be fulfilled for sub-assemblies :assemblies:
MAMBO Front-End
MAMBO Back-End
MAMBO PDCU
5.1 Front-End
MAMBO Front-End is composed of the following equipment units :
"Cassegrain" telescope (off-axis Cassegrain or Newton type)
scan mechanism
calibration load
receiver
Note: the FOV is dependent of the location of MAMBO onboard the Orbiter. The FOV is not restricted (TBC).
5.1.1 "Cassegrain" Ttelescope
MAMB-R-04530 Antenna dimension
The telescope antenna shall be as large as possible taking in account AD6 Requirements for available volume and mass.
MAMB-R-04640 Instrument size
The total size of the instrument along the rotation axis shall be less than 500 mm
MAMB-R-0470 Antenna orientation
The antenna shall be such that it allows nominally to observeobserving the limb in the perpendicular plane wrt the Orbiter trajectory that is in cross-track mode.
MAMB-R-048750 Side lobes
Mambo antenna shall be designed so that the planet surface emission does not contaminate the limb observations.
MAMB-R-049860 Antenna beam
For given side lobes, the antenna beam width shall be as narrow as possible. Antenna efficiency shall be greater than 0.95 (this means a side lobe contribution not exceeding 5% of the total power).
MAMB-R-0504970 1st side lobe
the antenna 1st side lobe shall be around 30 dB (TBC).
5.1.2 Scan mechanism
MAMB-R-0510480 scan mechanism geometry
The scan mechanism shall be compliant with the measurement geometry described in table 2.4-2.
MAMB-R-0520 FOV
The scan mechanism shall be such that it allows nominally to observeobserving the limb in the perpendicular plane wrt the Orbiter trajectory that is in cross-track mode.
MAMB-R-0490 05310 scan mechanism rotationThe scan mechanism (rotation, pointing, lock) shall be fully controllable by the on-board computer.
MAMB-R-054200 scan mechanism pointing accuracy
The scan mechanism shall allow getting a 3-sigma pointing accuracy of the scan mechanism shall be 0.02 °.
MAMB-T-055310 scan mechanism operationThe scan mechanism shall operate step by step. The alternative is to operate the antenna at a constant rate during limb and nadir scanning.
MAMB-R-056420 scan mechanism stepsIf operated step by step, the scan mechanism shall operate with steps smaller or equal to 0.08 °.
MAMB-R-057530 scan mechanism rotation linearityIf operated at a constant rate, the scan mechanism rotation linearity shall be TBD.
MAMB-R-058640 scan mechanism transferreaction torqueThe scan mechanism shall allow a transfer between successive modes (nadir pointing, limb pointing, internal load pointing) in less than reaction torque shall be less than 0,.1 N.m TBC.3 sec.
MAMB-TR-05970 scan mechanism transferThe scan mechanism shall allow a total transfer time between successive modes (nadir pointing, limb pointing, internal load pointing) in less than 3 s forover 120 deg/.
5.1.3 Calibration Load
MAMB-R-060005850 receiver gain calibration
Gain fluctuation effects shall be removed by a two-point calibration every TBD scan period.
MAMB-R-06105960 receiver cold calibration
One of the two calibration points shall consist in a cold target measurement.
MAMB-R-0570 06200 receiver hot calibration
One of the two calibration points shall consist in a hot load measurement. The hot load brightness temperature shall be above 300 K.
MAMB-R-0580 06310 hot calibration load temperature accuracy
The hot load calibration temperature shall be known with an accuracy better than 0.1 K (TBC).
5.1.4 Receiver
MAMB-R-0590 06420 Receiver bandwidth
The receiver is fixed-tuned. The total bandwidth of the receiver is 323.0 – 348.0 GHz.
MAMB-R-065300 Receiver equivalent noise temperature
The receiver equivalent noise temperature shall be below 1500 K DSB.
MAMB-R-066410 Receiver phase-locked
The receiver is phase-locked with a frequency stability compliant with the USO short term stability.
MAMB-R-067520 Receiver gain stability
The receiver gain stability G/G shall be better than TBD.
MAMB-R-068630 Receiver gain ripple
The receiver gain ripple per channel is TBD. The receiver gain ripple over the full bandwidth is TBD.
MAMB-R-069740 Receiver channel
The receiver shall be a dual channel receiver separating the two perpendicular polarisation axes (polarisation angle is TBD depending on scanning mode).
MAMB-R-07006850 Receiver thermal control
The receiver shall be thermally isolated from the orbiter.
MAMB-R-0710660 Receiver thermal control
The receiver shall be designed such that the temperature range and thermal stability are ensured.
MAMB-R-07200 Receiver thermal stability
In order to ensure the receiver gain stability over the required period, the temperature of the receiver shall be maintained stable with a gradient of 0.1 K per minute TBC.
MAMB-R-07310 Receiver two-point calibration
In order to ensure a satisfying calibration (signal to noise ratio better than 90%), the receiver gain shall be stable over 10 integration cycles (a cycle is a 360° scan sequence) that is a minimal period of 12min TBC.
Note: In order to get a satisfying noise level (at -30 dB), the calibration time has to be around 100 times the observation (limb or nadir) integration time. For an observation integration time of, e.g., 1 s, the calibration time has to be aroudaround 100 s.
Therefore, iin order to improve calibration accuracy, one calibration spectrum over 10 s per cycle (360° rotation of the scan mechanism) can be madedone. Oonboard data processing could then filter calibration data over 10 (TBC) cycles . The filtering method would useing a weighting function (which remains TBD).
An other solution is to make a calibration of 100* s (where is the integration time for one spectrum, 1-5 sec TBC) every 10 cycles.
The number of spectraa during hot/cold load integration total time is TBD: it might be possible to get either one spectrum averaged over 10 s or 5 spectra of 2 s each.
MAMB-R-740 Calibration periodicity
The calibration periodicity required to remove low-frequency gain variations is TBD.
Note:
The upper requirement has to be considered due to its impact on the design of the instrument (addition of a secondary mirror dedicated to calibration, for instance)
5.2 Back-End
MAMBO Back-End is composed of the following equipment units:
USO
Frequency synthesiser
IF processor
Spectrometer
DPU & PDU.
5.2.1 USO
MAMB-R-0670 07250 USO long term stability
USO Long term stability shall be better than 10-7 (TBC).
MAMB-R-0680 07360 USO short term stability
USO short term stability shall be better than 10-8 (TBC).
MAMB-R-0690 07470 USO phase noise
USO phase noise shall be better than –150dBc/Hz in the range 10 Hz - 10 kHz TBC TBD.
5.2.2 Frequency synthesiser
MAMB-R-700 07850 Frequency synthesiser design
The frequency synthesiser is phase-locked on the USO.
5.2.3 IF processor
MAMB-R-079610 IFP design (amplification and filtering)The IFP design shall ensure the down-conversion, amplification and filtering of the mixer output in order to provide the input signal for the spectrometers.
MAMB-R-08007720 IFP design (detection and digitalisation)The IFP design shall include two continuum channels and ensure the down-conversion, detection and digitalisation of the signal. The bandwidth of each channel is TBD.
MAMB-R-08107830 IFP performanceThe IFP performances shall be in accordance with the receiver requirements (section 6.1.4) and comply with the spectrometers input power levels.
MAMB-R-08207940 IFP spectral linesEach spectral line is filtered so as not to contribute to excess noise outside its allocated bandwidth (rejection is TBD).
MAMB-R-08300 IFP spectral calibrationSSB spectral line calibration (using frequency switching for instance) is TBD.
Div
iseu
r
Front-End N°1
1.144 - 6.463 GHz
CO
1,9 ± 0.29 GHzContinuum
The bandwidths correspond to the useful signal frequencies
Pow
er D
ivid
er
Wid
e ba
nd a
mpl
ifier
s
Spectrometer N°1
Detector
Filters + Detectors or Autocorrelators (B = 2.048 GHz)
Div
ider
1.35 ± 0.1 GHz
2.685 GHz
IF Signal
Front-End N°2
1.9± 0.29 GHzContinuum
Detector 1.9 ± 0.29 GHz
Pow
er D
ivid
er
Mix
4.035 ± 1.024 GHz
PLO 3
1.35 ± 1.024 GHz(LO1 = 341.761 GHz)
(LO2 = 329.188 GHz)
1.144 - 6.463 GHz
Mix
4.035 ± 1.024 GHz 1.35 ± 1.024 GHzH2O
Div
ider
Spectrometer N°2
1.35 ± 0.1 GHz
1.35 ± 0.1 GHz
6.207 ± 0.256 GHz 1.3 ± 0.256 GHz
Mix
4.907 GHz
PLO 42.248 ± 0.1 GHz
Mix
3.598 GHz
PLO 5
1.35 ± 0.1 GHzO3 et H2O2
Com
bine
r
HDO
1.35 ± 0.1 GHz
13CO1,4 ± 0.256 GHz
T B C
sele
ctor
(op
tiona
l)
Div
ider
Spectrometer N°3
Spectrometer N°4
1.9 ± 0.29 GHz
Filters + Detectors or Autocorrelators (B = 2.048 GHz)
Filters + Detectors or 2 Autocorrelators (B = 512 GHz)
Div
iseu
r
Front-End N°1
1.250 - 6.187 GHz
CO
1,85 ± 0.35 GHzContinuum
The bandwidths correspond to the useful signal frequencies
Pow
er D
ivid
er
Wid
e ba
nd a
mpl
ifier
s
Spectrometer N°1
Detector
Div
ider
1.35 ± 0.1 GHz
2.735 GHz
IF Signal
Front-End N°2
1.85 ± 0.35 GHz
1.85± 0.35 GHzContinuum
Detector
Pow
er D
ivid
er
Mix
4.085 ± 0.8 GHz
PLO 3
1.35 ± 0.8 GHz(LO1 = 341.711/2
GHz)
(LO2 = 329.238/2
GHz)
1.250 - 6.187 GHz
Mix
4.085 ± 0.8 GHz 1.35 ± 0.8 GHz
Spectrometer N°3
Filters + Detectors (5) or Broad band Spectrometer
Div
iderH2O (325)
Spectrometer N°2
1.35 ± 0.1 GHz
1.35 ± 0.1 GHz
6.157 ± 0.03 GHz 1.42 ± 0.03 GHz
Spectrometer N°4
Mix
4.737 GHz
PLO 42.298 ± 0.07 GHz
Mix
3.618 GHz
PLO 5
1.32 ± 0.07 GHzO3 et H2O2 C
ombi
ner
HDO
1.35 ± 0.1 GHz
13CO1,35 ± 0.1 GHz
T B C
sele
ctor
(op
tiona
l)
1.85 ± 0.35 GHz
Filters + Detectors (5) or Broad band Spectrometer
Figure 6.2.3-1 Temporary Indicative schematic drawing of the IF processor with the dual channel receiver. This drawing is coherent with the suggested spectrometer design (see next section).
5.2.4 Spectrometer
MAMB-R-0750 08410 Back-End design
The Back-End architecture shall include four set of spectrometers including Chirp Transform Spectrometers (CTS) and/or Auto-Correlators (A-C) and/or filter banks
MAMB-R-0760 08520 Spectrometers design (bandwidth)
The CTS-type spectrometer bandwidth shall be 200 MHz or 400 MHz
MAMB-R-0770 08630 Spectrometers design (CTS ; resolution)
The CTS-type spectrometer resolution shall be in the range 100 50 kHz to 400 kHz (TBC)
MAMB-R-0780 08740 Spectrometers design (central frequency)
The CTS-type spectrometer central frequency shall be 1.35 GHz. or 3 GHz (TBC)
MAMB-R-0790 08850 Spectrometers design (A-CDAC ; resolution)
The A-CDAC-type spectrometer resolution shall be in the range 2 MHz to 20 MHz (TBC)
MAMB-R-089600 Spectrometers design (A-CDAC ; bandwidth)
The A-CDAC-type spectrometer bandwidth shall be in the range 400 MHz to 2 GHz TBDTBC.
MAMB-R-09008710 Spectrometers design
If filters banks are use, the frequency and bandwidths are TBD.
Note on the baseline of spectrometer design: Reminder: The goal is to observe the following lines at nadir and at the limb:
• CO at 345,796 GHz • 13CO at 330,588 GHz
• H2O at 325,153 GHz• HDO at 335,395 GHz• O3 at 326.901 GHz• H2O2 at 326,981 GHz
Limb observation is more constraining and has to be used to drive the baseline choices.
MAMB-R-0910 Spectrometers design
Each line can be observed with a combination of 2 kinds of spectrometers:
1. A set of chirp transform spectrometer (CTS)
2. 2. A set of digital autocorrelation spectrometers (DAC)
The requirements for the spectrometers is driven by the line characteristics.
MAMB-R-0920 Spectrometers design (CTS)
The center of the lines shall be observed at high spectral resolution by the CTS.
MAMB-R-0930 Spectrometers design (DAC)
To ensure a good processing of problems related to ripples and baseline, and to monitor the wings of the lines when the center of the lines are saturated, the other part of the lines (wrt R-0920) shall be observed with a sufficient bandwidth by the DAC.
Two kind of DAC could be used to cover the total bandwidth of the lines :- DAC type 1 (for CO and H2O): Minimum : 20010 MHz channels.
Total bandwidth : 2 GHz. - DAC type 2 (for 13CO and possibly HDO): Minimum : 4010 MHz channels.
Total bandwidth : 400 MHz.
4 CTS + 4 DAC baseline:To minimize the complexity of the spectrometer subsystem, the suggested baseline design is the following :1. CTS #1 (resolution : 50 or 100 kHz):
CO (CTS Bandwidth=200 MHz) completed by 1 DAC type 12. CTS #2 (resolution 100 kHz)
H2O (CTS Bandwidth=200 MHz) completed by 1 DAC type 13. CTS # 3 (resolution 100 or 200 kHz)
O3-H2O2 (CTS Bandwidth 200 MHz) 4. CTS #4 (resolution 50 or 100 kHz)
HDO (CTS Bandwidth=100 MHz) completed by 1 DAC type 213CO (CTS Bandwidth=100 MHz) completed by 1 DAC type 2These lines are obtained within a single 200-MHz CTS.
This baseline suits the scientific objectives while adding at the same time redundancy between the 2 kind of spectrometers: mass, volume and power are TBD.
5.3 Power and Data Control Unit
MAMBO PDCU is composed of the following equipment units :
DPU,
PDU.
5.3.1 DPU
MAMB-R-08820 0940 DPU design
The DPU shall be designed in accordance with AD6 requirements.
MAMB-R-09508930 DPU mass memory
DPU and memory size shall be able to store 3 days of compressed data: 3 Gbits. (TBC)
MAMB-R-0840 09600 DPU TM
Telemetry (TM) needs are TBD.
MAMB-R-0850 09710 DPU functions
The DPU shall be designed in order to achieve the following functions:
1) Control & Housekeeping of the instrument sub-systems
2) Antenna pointing control
3) Scanning sequence control
4) Spectrometers and continuum channel data collection
5) Data spectral binning and smart compression
6) Compute limb position from information provided by the Oorbiter computer
7) Handle Telecommand (TC) from Earth.
MAMB-R-0860 09820 DPU multi-task mode
The DPU shall be designed in multi-task mode. MAMBO remains under operation while compressing 16-bit data and transmitting compressed data to the orbiter in real-time.
MAMB-R-0870 09930 DPU data handling
The DPU shall be designed to handle a data rate incoming from the spectrometers of up to 10,000 16-bit coded data per second.
5.3.2 PDU
MAMB-R-0880 10000940 PDU design
The PDU shall be designed in accordance with AD6 requirements.
MAMB-R-0890 10100950 PDU power supply design
The PDU architecture shall avoid power supply variations (level TBD) by separating the power sources of the different sub-systems.
6 OPERATIONAL REQUIREMENTS
6.1 Life duration / Mission duration
MAMB-T-102009600 Life durationThe minimal life duration on mission of MAMBO instrument shall be 4 terrestrial years.
MAMB-T-103009710 Mission duration
MAMBO instrument shall be able to sustain a mission duration of 5 terrestrial years.
MAMB-R-104009820 On-ground storageThe on-ground storage duration capability shall be at least 2 terrestrial years.
MAMB-R-105009930 GSE life durationThe duration of life for simulators, test beds and Electrical Ground Support Equipment shall be 7 years (after acceptance by the customer).
6.2 Reliability
The general approach is defined in AD3.
6.3 AvailabilityNo requirements.
6.4 Autonomy, Observability & Commandability
MAMB-R-0940 10600 Command / Control
MAMBO shall be compliant with the general Command/Control requirements defined in AD6.
6.4.1 MAMBO ancillary data
MAMB-R-10710 Orbiter attitude data
MAMBO shall include the Orbiter attitude quaternion (provided at 1 Hz rate by the Orbiter) to each measured spectrum.
MAMB-R-10820 Orbiter On-Board Time data
MAMBO shall include the Orbiter OBT (provided at 1 Hz rate by the Orbiter: OBT+Reft) to each measured spectrum.
MAMB-R-10930 MAMBO antenna positioning
MAMBO shall include the antenna positioning to each measured spectrum.
6.5 Programming of MAMBO instrument
MAMB-R-0950 1100040 programming
MAMBO programming shall be compliant with defined operation sequences and PCDU requirements.
6.6 MAMBO operating modes
MAMB-R-0960 1110050 operating modes
MAMBO modes shall be compliant with defined operation sequences depending on the observation strategy schedule (see § 2.4). Typical and dimensioning mission profiles are TBD. (see figure 7.6-1 as maximal scan mechanism dimensioning profile)
figure 7.6-1: example of worst-case angular rate scanning sequence.
Note: the 0-deg reference corresponds to the internal hot load position. The duration in this schematic must be considered as purely indicative. This worst case analysis leads to short intermediate position change duration in accordance with R-05960.
During limb scanning, as already said, a spectrum is obtained every 5 km, which corresponds to one measured spectrum every 1 to 5 sec.
Nadir integration times (which are not represented in this worst-case example) are TBD.
Repeatability of the orbits will allow to improve ground (Earth) post-processed signal to noise ratio. This ratio is TBD.
Hot/Cold load integration times are as explained in section 6.1.4.
MAMB-R-112060 Safe mode
MAMBO modes shall include a "safe mode" whitch will be able to interrupt immediately any MAMBO active modes and perform a scan mechanism command in order to get a safe antenna positioning in a few seconds.
MAMB-R-1130 Sun protection modeWhen the Sun is in the FOV of the antenna, the scan mechanism shall be able to position the antenna in a forced stand-by mode in which the antenna will be looking at the internal hot load in order to keep safe the receiver Front-End.
7 DEVELOPMENT REQUIREMENTS
7.1 Assembly Integration & Tests Requirements
MAMB-R-0970 114070 Performance verification
The Performance Verification Plan and/or Design Verification Matrix shall be constructed with all the performance requirements described in this document and its applicable documents.
MAMB-R-0980 1150080 Integration and Test Plan
An Integration & Test Plan shall be defined and presented, followed by Test Specifications, Test Plan, Procedures and Reports. Integration & test plan and all Test specifications documents shall be accepted by OP and CNES.
MAMB-R-0990 116090 Verification method
The compliance to specifications shall be verified by test, analyses, inspection and review of design.
MAMB-R-1170000 Compliance matrix
The compliance matrix to the requirements defined in the present document shall be done with an associated justification document.
MAMB-R-1180010 Reference test
Functional/ performance Reference Tests shall be performed before and after environment tests prior to any statement of success.
MAMB-R-11901020 Software test requirements
The general test requirements of the On-Board Software shall be found in AD3.
MAMB-R-12001030 GSE
The Ground Support Equipment and Integration Tools shall not endanger the instrument, even in case of a failure in the GSE.
MAMB-R-12101040 Number of tests
The number of tests shall be minimised by the optimisation of the coverage of tests. This optimisation shall be justified.
MAMB-R-12201050 AIT Quality Assurance
The general requirements of Assembly Integration & Tests Quality Assurance shall be found in AD3
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