Sensor field produce diagnostic data, small size and slow rate: ... synchronous sleep/wakeup cycle bound to radio protocols ... PickCell: image analysis and ... UHF/VHF. S'Band. Lora. Antenna& 50&cm&+&6&m 50&cm&+&6&m 50&cm&+ ...
Bernard Pottier, 6 Juillet 2015
Wireless sensor networks and satellite simulation
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Pierre-Yves Lucas, NGuyen Van Long, Tuyen Phong Truong and Bernard Pottier http://wsn.univ-brest.fr/pottier
Université de Brest, France Lab-STICC
Sensor fields for distant environment monitoring ❖
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Sensors use expand in smart cities: parking management, light, noise, pollution, bus lines Sensors are also used in the country : agriculture, climate change Deployments use communication networks on a variety of ranges : phone cells, wireless specific, wired Environment monitoring need more : distant places such as deserts, shores, polar regions, oceans, island, mountains ❖ lack communication facilities ❖ are critical for climate changes, observation of life and physical evolutions 2
Why sensor fields to satellite is attractive
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Sensor field produce diagnostic data, small size and slow rate: ❖ based on periodic collective computation ❖ synchronous sleep/wakeup cycle bound to radio protocols ❖ frequency is adapted to physical observation needs
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Satellite periodic communications match these requirements ❖ predictible, possibly synchronized with ground sensors ❖ can reduce ground network topology and workload ❖ opportunity to build free distribution/control service 3
Micas project Existing Tools ❖ Quickmap: dedicated map browser for geo-localized sensor placement ❖ NetGen: translate sensor networks model into concurrent process systems ❖ PickCell: image analysis and production of concurrent cell systems for physical simulation
Status ❖ Contribution to a platform for oceanographic instrumentation (iROMI) ❖ Project of a nano satellite for data collection on distant sensor fields ❖ Needs simulation for data collection and control service
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Ground software views Cell systems Model & controls
OSMap
Sensor network Location elevation
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Tool extensions for Micas Right : GPredict Left: Quickmap Green: contacts Red: lost links Blue: ground net Black : Aalborg Cubesat
Data collection over fictive sensor field: ground radio network, satellite prediction, dynamic links 6
Objectives for Micas simulation • • • • • •
Network architectures design and evaluation Automatic synthesis of concurrent simulators (GPU & threads) Distributed behaviour libraries Qualification of solutions under time constraints Data presentation, compression, in-field processing, Metrics : data rate, latency, energy consumption
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Network, mobile and physical multi-simulation framework: Occam and CUDA targets
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NetGen : simulation of sensor networks • Nodes are sensors • Edges are communication links
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PickCell : simulation of physical process • Nodes are cells • Edges are physical influences
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Satellite visits : • Mobile nodes • Dynamic links 8
All synchronous, different time references All parallel sharing synthesis tools for process oriented (Occam) and GPU execution (CUDA)
Scheduling simulation •
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Sensor field : • loops • neighbour communication • message analysis • sensing • sleeping • change of state
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Satellite : • loops • discrete step moves • ground communication • message analysis • change of state
Use of gpredict to obtain satellite moves Network developed inside GPU memory Patched to manage dynamic links 9
Migration to an HLA framework
Writing simulations •
Architecture (automatic): • one process per node • channel representing node communication capabilities • provision for sat visits
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Behaviour files (reusable): • distributed algorithms • networking activities • trace production
MIMD : Occam, SIMD : CUDA
compiler trace 10
Mobile-ground: transaction, flow Satellite Satellite out Satellite in
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algorithms Satellite
Diameter + Breadth first search • downward • upward
Satellite out Satellite in
Diameter + 2 BFS source to sink 12
Trace and metrics • • • • • • •
Algorithm correctness communication load energy budget ground (network cycles) and air (satellite move) race radio links evaluation and broadcast possible optimisations scheduling ground activities for satellite visit memory budgets
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Comparing radio link for LEO UHF Antenna&
VHF
UHF/VHF
50&cm&+&6&m 50&cm&+&6&m 50&cm&+&6&m
S'Band
Lora
76&mm&(diameter)
10+30&cm
Data&rate ~100&Kbps
~100&Kbps
~100&Kbps
1+2&Mbps
~300&Kbps
Power
0.5&+&2&W
0.5&+&2&W
0.5&+&2&W
3+6&W
100&mW
Distance
~1200&Km
~1200&Km
~1200&Km
~&1200&Km
200+600&Km
8000+9000&USD
8000+9000&USD
90&USD
Cost
→&To&propose&direct&radio&links&between&sensor&fields&and&LEO& satellites&Concurrent&&based&on&the¤t&innovation&solutions& such&as&LoRa&Semtech,&solutions&from&vendors&QB50&etc.& References:& http://www.clyde+space.com/cubesat_shop/communication_systems& http://www.isispace.nl/cms/index.php/products+and+services/products& http://www.digikey.com/product+search/en?mpart=SX1276RF1KAS&vendor=600& http://www.instructables.com/id/Introducing+LoRa+/step19/LoRa+receiver+links/
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Perspectives Practical feasibility and constraints: low cost, low energy • Design of ground and sky systems • Micro controllers : Arduino, TI, Raspberry, Galileo, NVidia … • Communication transceivers : TI CCxxx, Semtech LoRa, .. More simulation • Including radio links and footprints, satellite speed factor • ground applications for environment monitoring • service simulation several ground clients, several sensor fields • HLA federation, multi languages
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Thank you
For further informations: http://wsn.univ-brest.fr/pottier
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