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Wireless Sensor and Actuator Networks

Paweł Kułakowski

UdG, Catalunya, Spain AGH, Poland

Research Ideas and Discussion

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Presentation outline

1. WSANs and their APPLICATIONS

2. Network ARCHITECTURE

3. WIRELESS aspect and network design PRINCIPLES

Paweł Kułakowski, BCDS, Girona, February 2010

4. POSSIBLE RESEARCH topics

0. Rather BRAINSTORMING than presentation

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Wireless Sensor and Actuator Networks

A network of (small and simple) wireless devices that:a) gather the data about any events in the environment,b) deliver it to a control centre / make decisions autonomously,c) react appropriately.

Applications:• environment control• indoor control• street traffic supervision• military• ...• hospital patient tracking

Paweł Kułakowski, BCDS, Girona, February 2010

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Wireless Sensor (and Actuator) Networks

Current situation :• more than 10 years of research• thousands of papers published• multiple sessions during the main IT conferences• the research mainly by simulations, some measurements• IEEE 802.15.4 standard suitable only for some applications

• a very BROAD and BLURRED topic (+/-).

Paweł Kułakowski, BCDS, Girona, February 2010

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Application examples

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Network architecture

... to a DISTRIBUTED

and SELF-ORGANIZED

network.

From CENTRALIZED...

Paweł Kułakowski, BCDS, Girona, February 2010

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CLUSTER / MODULAR architecture

Paweł Kułakowski, BCDS, Girona, February 2010

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Introducing Wireless Aspect

• only broadcast transmissions, no point-to-point links • multi-hop connections• wireless channel variations and fadings, unstable links

• MAC protocol, routing, task scheduling, packet collisions

• limited energy supplies (batteries)

No, if the decisions are taken locally.

Paweł Kułakowski, BCDS, Girona, February 2010

Does the signalling overhead cause the wireless distributed system to collapse?

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Self-organized WSANs: Principles

1. Decisions taken LOCALLY to achieve GLOBAL properties

→ examples: power-controlled connectivity, collisions solved locally→ open issue: emergent behaviour → bio-inspired networks :

• swarm intelligence• ant-colony behaviour

3. ADAPTIVITY and RECOVERY from changes

→ examples: reactive protocols

2. SCALABILITY and ROBUSTNESS in irregular topologies

→ example: exploiting geographic data – geo-routing

Paweł Kułakowski, BCDS, Girona, February 2010

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Research Topics

Paweł Kułakowski, BCDS, Girona, February 2010

Obvious liaisons with other research disciplines:

• multi-robot systems (Robotics)• distributed and multi-agent networks (Informatics)

Intensively exploited topics:

• architecture proposals• MAC algorithms• routing protocols• localization schemes • clustering algorithms• scheduling / task allocation schemes

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Research Topics, contd

Paweł Kułakowski, BCDS, Girona, February 2010

Adaptives techniques of context-aware data transmission:

• a distributed WSAN acts as a server • the decision about the transmission parameters

is taken cooperatively by sensors:

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Application examples, contd

MUNICIPAL NETWORKpossibly deployed in ad-hoc manner (partially) for some events: (Temps de Flors, Las Fallas, Reyes Magos)

Independent modules:

• lighting control

• event filming • cooperative data

processing, compressing and transmission (live)

• security control, electronic tickets

• fire protection system • medical warnings

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Moltes Gràcies!