The University of Iowa. Copyright© 2005 A. Kruger 1 Introduction to Wireless Sensor Networks 20 January 2005

The University of Iowa. Copyright© 2005 A. Kruger 2 Organizational Class Website Class Time and Place Monday 4:30-5:20Room 4511 SC Thursday12:30-1:20Room 3220 SC Please note that the room numbers are different for Mondays and Thursdays.

The University of Iowa. Copyright© 2005 A. Kruger 3 Confusion of Terms Berkeley Mote ZigBee Directed Diffusion Localization Rumor Routing Crossbow MAC Protocols Self-Organizing Networks Tiny-OS Tiny-DB Power Management RSSI ISM Band RFID Smart Dust ?

The University of Iowa. Copyright© 2005 A. Kruger 4 Mote “Tiny piece of anything” Low-power (RF) transceiver Microcontroller Operating system Crossbow mote with battery

The University of Iowa. Copyright© 2005 A. Kruger 5 Mote Transceiver 400 MHz and up –Line-of-sight –Short range –Unlicensed operation Microcontroller –ATmega MHz, 128KB Flash, 4 KB RAM –Low power, sleep modes TinyOS –Makes programming much, much easier

The University of Iowa. Copyright© 2005 A. Kruger 6 Operating Systems MSDOS, Windows, Linux, TinyOS NOT the interface, but The program that manages all other software and the hardware resources Provide services to other programs “applications” (encapsulate common tasks) For example, a simple task such as writing a few bytes to a disk without an OS is a significant task Isolate programmer from hardware

The University of Iowa. Copyright© 2005 A. Kruger 7 Sensor Network Interface electronics, radio and microcontroller Soil moisture probe Mote Antenna Gateway Server Internet Communications barrier Sensor field

The University of Iowa. Copyright© 2005 A. Kruger 8 Sensor Network Gateway Server Internet Sensor field Watershed

The University of Iowa. Copyright© 2005 A. Kruger 9 How Did We Get Here? Advances wireless technology –MEMS, VLSI –Bandwidth explosion Changes in regulation Cultural changes –Wireless devices are everywhere and people are receptive to new applications –The concept of networks are ingrained in culture –Open source Computer Science –Operating system theory, network theory –Inexpensive compilers

The University of Iowa. Copyright© 2005 A. Kruger 10 Wireless Revolution Boston central telephone station at 40 Pearl Street after the blizzard of 1881

The University of Iowa. Copyright© 2005 A. Kruger 11 Wireless Revolution TI REGENCY TR-1, 1955, $450 (today) 1 st Transistor, 1947 Sony TR-610, 1958 Integrated Circuit, st Integrated Circuit, ~1958 Today ~$5

The University of Iowa. Copyright© 2005 A. Kruger 12 Wireless Revolution Size reduction of cellular telephones

The University of Iowa. Copyright© 2005 A. Kruger 13 Micro-Electro-Mechanical-Systems (MEMS) ~ 1mm

The University of Iowa. Copyright© 2005 A. Kruger 14 Micro-Electro-Mechanical-Systems (MEMS) ~ 1mm

The University of Iowa. Copyright© 2005 A. Kruger 15 Small Sensors ~ 5 mm Sensor uses electrochemical and photonic properties to perform bioanalysis

The University of Iowa. Copyright© 2005 A. Kruger 16 RF MEMS MEMS Filters: Qs of 98,000 in vacuum, very small Conventional LC Filters - Qs of , significant board space

The University of Iowa. Copyright© 2005 A. Kruger 17 Transceiver

The University of Iowa. Copyright© 2005 A. Kruger 18 Computer Revolution 0.5 oz, 2.25 x 1.25 x 0.25 inch 25 lb, 19.5 x 5.5 x 16 inch ~14 mW~ 64 W ~ $35~ $6K (today) 512 KB Flash160 KB Floppies 128 KB RAM KB RAM 4 MHz4.77 MHz MICAZ Mote (2005)Original IBM PC (1981)

The University of Iowa. Copyright© 2005 A. Kruger 19 Sensor Network Gateway Server Internet +

The University of Iowa. Copyright© 2005 A. Kruger 20 Next Time: Telemetry vs. Sensor Networks