Key Mission Systems Engineering Trades For Determining Satellite System Architecture GSAW 98 Paul Nussbaum Page 1 Introduction Presentation will focus on the common key mission system engineering tradeoffs that must be performed for determining the best space ground and operations architecture for a satellite system Mission system engineering is the single most effective measure a project can undertake to lower the total system cost Mission system engineering aims at finding the overall optimum system design solution Page 2 Strategies and Techniques For Low Cost Space Mission Operations Mission System Engineering Develop a vision for the system Vision lays out the mission system engineering trades in a perfect world Develop guiding principles for the system that define system constraints and key design operating rules World is no longer perfect but must take into account constraints Develop a concept of operations from which requirements can be generated Should be developed prior to the requirements so can define trades which affect requirements development Define the Mission System Engineering architecture trades Satisfying mission objectives for operations space and ground at lowest cost Page 3 Operations Concept Trade Development Determine mission operations functions to be performed What Why Identify options for accomplishing functions How Where Consider the degree of automation or autonomy to be implemented and what organization or teams will be responsible for each function Who Identify if functional capability exists or must be developed Develop operations scenarios based on options including timelines When Assess candidate operations concepts based on utility complexity performance reliability and cost Select a baseline operations concept Identify derived requirements and cost and complexity drivers Negotiate changes to mission concept Page 4 Ground Segment Trade Development Establish communications architecture Establish number and locations of ground stations account for orbital aspects account for treaties e g ABM account for geographic conditions i e weather natural disaster covert communications interference Establish space to ground data rates Determine required antenna G Ts and EIRPs Determine data flow and data handling Establish complete or partial use of service provided ground systems Determine the development approach include the following what will be custom Off The Shelf evolutionary prototyping SEE tools Page 5 Space Segment Trade Development Establish communications architecture space to space space to ground Consider on board autonomy such as One or more simple and reliable safe modes triggered on board autonomous telemetry monitoring and alarming autonomous anomaly detection correction and reporting autonomous orbit management autonomous memory management Mission data processing performed on board as part of the payload or should it be performed on the ground Page 6 Summary Space and Ground Trades Trade Objective Options S G Links Determine GS connectivity to satellites S band SHF EHF other also need to determine bandwidth Mission Processing Determine optimal split between space and ground Space to reports space to exceedances ground to reports other Ground HW Architecture Determine network and ADPE architecture Homogeneous vs Heterogeneous Mission Management Scheduling Determine concept for multi constellation system Contractor developed or COTS based augmentation Ground Cost Model Determine cost modeling approach evaluate CERs Comparison to like existing systems Page 7 Summary Space and Ground Trades Cont Trade Objective Options Ground Entry Points Determine required and preferred locations MGSs Primary Backup GEPs RGFs RGSs Commercial terminals Anomaly Resolution Required capability and S G partitioning Level of Sat autonomy vs Ground autonomy Operations and Staffing Determine preferred concept for ground ops including ops positions and staffing Integrated vs separated positions and ops Transition Plan Define low cost risk transition path Existing MGS MGSB or contractor facility 1st transition Ground Survivability Efficient ground survivability endurability solution Mobile Component Facility Harding Diverse Geographic Location Page 8 Summary Space and Ground Trades Cont Trade Objective Options P4I Provide efficient ground growth path Mobiles Efficient incorporation of Upgrade of existing new endurable mobile missions or hybrid System Activation Interfaces External Efficient activation of operations Partial to full constellation Solid understanding of functional interfaces Open distributed COTSbased architectures Contractor support MGS or MGSB activation Specific procedures Minimal impact except for new products Page 9 Mission System Engineering Low Cost Considerations Key factors affecting ultimate mission operations cost are Complexity of the mission being attempted Operability of the S C performing the mission Operability of the mission operations system Management policies regarding operations especially risk avoidance General low cost approaches are Eliminating or combining functions Performing functions more efficiently Using lower cost staff Assuming greater risk Page 10 Summary Mission System Engineering trades should consider the following cost reduction methods Reusing existing facilities which can significantly reduce development and test efforts and increase system reliability Using COTS components with contractor augmentation where necessary Adhering to standards however be aware of standards that constrain functionality Leveraging testing and operations commonalities to produce savings due to combined development and reduction in operations training cost Page 11