Light Sensing Wireless Network with Energy Efficient Routing Algorithm Man-Ting Au Thanh Nguyen Marie Shinotsuka Thomas To Georgia Institute of Technology School of Electrical and Computer Engineering March 6, 2008

3/6/2008Light Sensing Wireless Network2 Presentation Outline Objectives Overall Network Technical Objectives Hardware/Software Components Demonstration Plan Acceptance Test Cost Analysis Problems and Solutions Project Schedule

3/6/2008Light Sensing Wireless Network3 Objectives Implement a routing algorithm for a wireless sensor network that determines its routing path based on light conditions of nodes Provide a basic structure for research groups focused on energy efficient wireless sensor network Provide a package, including all hardware and software components, for $2, with 15.19% profit

3/6/2008Light Sensing Wireless Network4 Overall Network Base Stations –Communicate with PC –Receive information packet from nodes –Transmit or receive data Intermediate Nodes –Forward data from transmitter to receiver –Send information packets periodically

3/6/2008Light Sensing Wireless Network5 Technical Objectives Data route only contains nodes that are sensing light, which ensure a most secure path Data route is chosen randomly if both paths are available, thus providing an evenly distributed workload Data is not transmitted when both nodes are not sensing light in order to prevent data loss and retransmission

3/6/2008Light Sensing Wireless Network6 MICAz (Wireless unit) –Low power –Frequency: 2.4GHz –Distance range: 20m-30m –3 programmable slots –3 LED lights (red, green, yellow) MTS400 (Sensor board) –Light intensity: lux (lm/m 2 ) –Spectral responsivity: 400 – 1000 nm –51pin connector for MICAz MIB520 (Programming board) –51pin connector for MICAz –USB cable for PC connection Hardware Components

3/6/2008Light Sensing Wireless Network7 Hardware Configurations MICAz MTS400 PCMIB520 MICAz USB Transmitter/Receiver Nodes

3/6/2008Light Sensing Wireless Network8 Software Components MoteWorks –Provides different applications (e.g. Programmer’s Notepad) for editing and compiling codes –Provides a library of programs written in nesC MoteView –Configures hardware using MoteConfig –Provides precompiled execution files for hardware verification –Displays received/transmitted data in tabular form –Stores data received/transmitted in PostgreSQL

3/6/2008Light Sensing Wireless Network9 2 nodes in the network Light measured by sensors attached to each node (Luminance / m 2 ) Next time instance MoteView

3/6/2008Light Sensing Wireless Network10 Data Management PostgreSQL –MoteView stores data as a table in PostgreSQL –Cygwin or Command Prompt used to view/modify stored data –Transmitter uses this table to decide routes Excel –MoteView can export data to Excel spreadsheet –Table used for acceptance test 2 nodes Light measured by sensors

3/6/2008Light Sensing Wireless Network11 Demonstration Lamp –Placed beside the intermediate nodes –Switch on and off manually Transmitter/Receiver –Display and store data sent/received Nodes –Turn on LED when forwarding data Data from Transmitter –Counts up by 1 for each new data packet Receiver Transmitter

3/6/2008Light Sensing Wireless Network12 Acceptance Test Data routed through the node that is sensing light –Check LED on nodes visually –Compare data sent to data received No data loss took place –Compare tables in transmitter and receiver CasesExpected results Lamp A is on and lamp B is offData will route node A Lamp B is on and lamp A is offData will route node B Both lamps are offData will not be transmitted Both lamps are onData will randomly choose a node

3/6/2008Light Sensing Wireless Network13 Cost Analysis Based on:500 units Parts Cost$ Labor Costs per unit$66.00 Overhead, 60% of Material, Labor & Fringe$ Sales Expense$40.00 Amortized Development Costs$43.35 Subtotal, All Costs$1, Profit per unit$ Selling Price per unit$2, Total Revenue$1,000, Total Profit$151, % Profit15.19%

3/6/2008Light Sensing Wireless Network14 Problems and Solutions Time delay between information packets sent from the two intermediate nodes –Decrease the time interval between two consecutive information packets to keep updating information known at the transmitter Considerable difference in language of nesC from C/Java –Study tutorials from official website –Make use of available codes provided in the MoteWorks library Direct communication between transmitter and receiver –Make sure transmitter and receiver are far away enough to prevent them from directly communicating

3/6/2008Light Sensing Wireless Network15 Project Schedule TasksDeadline Verify all hardware components2/25/2008 Obtain light intensity from MTS4002/29/2008 Test XMesh capability3/3/2008 Upload codes wirelessly (Over-The-Air-Programming)3/3/2008 Program intermediate nodes to transmit information packet3/14/2008 Test transmitter and receiver3/25/2008 Program routing algorithm for transmitter4/10/2008 Combine and test the entire network (debugging)4/18/2008

Questions?