Shahin Farshchi, Member, IEEE, Aleksey Pesterev, Paul Nuyujukian, Eric Guenterberg, Istvan Mody, and Jack W. Judy, Senior Member, IEEE, ” Structure of Wireless Sensors Network Based on TinyOS” IEEE TRANSACTIONS ON NEURAL SYSTEMS AND REHABILITATION ENGINEERING, VOL. 18, NO. 2, APRIL 2010 Presenter: Shao-Kai Liao Adviser: Tsung-Fu Chien Date: /7/20111

Outline  Introduction  Purpose  Methods & Materials  Conclusions 12/7/20112

Introduction  Structure of Wireless Sensor Network (WSN) MEMS (Micro Electro Mechanical Systems) Embedded system Wireless communication Distributed processing Sensor technology  微機電系統 ( Micro Electro Mechanical Systems ， MEMS)  無線感測器網絡 （ Wireless Sensor Network ， WSN ） 12/7/20113

Introduction  Application of Wireless Sensor Network High application values in domains of military, medical, industrial, agriculture and environmental monitoring. Development and application profound influence will be generated to every domain of human-being. 12/7/20114

Purpose  Advantages of Telosb node Low cost. Low power consumption. Small size. The structure of wireless sensor network directly affects system performance. 12/7/20115

Methods & Materials  Architecture Hardware ○ Self-organizing and multi-hop network. ○ A large numbers of sensor nodes. ○ Monitor the information comprehensively and in time. 12/7/20116

 Specifcation of Crossbow’s TelosB mote IEEE compliant 250 kbps, high data rate radio TI MSP430 microcontroller with 10kB RAM Integrated onboard antenna Data collection and programming via USB interface Open-source operating system Methods & Materials 12/7/20117

Methods & Materials  Telosb Two major goals: ○ Easy to use ○ Minimal power consumption(sleep quickly) 12/7/20118

Methods & Materials  The composition of the node Sensor module Processor module Radio module Energy supply module 12/7/20119

Methods & Materials  Distributed nodes 12/7/201110

Methods & Materials  The characteristics of node Since wireless sensor nodes are used to monitor. The node cost and energy supplies seem worthy of consideration. The transmission distance and the number of nodes must be balance. 12/7/201111

Methods & Materials  Architecture Software ○ Sleep and wakeup modes. ○ Concurrent tasks. ○ Programming interface and platforms. 12/7/201112

Methods & Materials  TinyOS A open-source lightweight operating system. Specifically designed for low-power wireless sensors. Implemented by NesC 12/7/201113

Methods & Materials 12/7/  Data Memory Model STATIC memory allocation! ○ No function pointers Global variables ○ Available on a per-frame basis Local variables ○ Saved on the stack

Methods & Materials  NesC C dialect with features to reduce RAM and code size. Programmers can define new components using a C - like syntax. 12/7/201115

Methods & Materials  Interfaces Two kinds of functions: ○ Commands ○ Events Users can call commands. Providers can signal events. 12/7/201116

Methods & Materials  Components Two types of components in nesC : ○ Modules ○ Configurations. A NesC application consists of one or more components assembled, or wired, to form an application executable. 12/7/201117

Methods & Materials  Execution Model Interrupting tasks at any time. A task posted are executed later. A task a lightweight deferred procedure call. 12/7/201118

Conclusions  Analyzing wireless sensor node telosb and the operating system TinyOS.  TinyOS is specifically designed for low-power wireless sensors  The telosb node with low cost, low power consumption and small size, 12/7/201119

Thank You For Your Attention 12/7/201120