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Electronics and Networks: Week 9: Dumb things without Wires RF / IR Communication. Jonah Brucker-Cohen Matthew Karau Monday 10am - 12pm Trinity College Dublin MSc. Multimedia Systems Spring 2003. Reading: Artistic Practice in the Network. Networks, Bodies, Symbols
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Electronics and Networks: Week 9: Dumb things without WiresRF / IR Communication Jonah Brucker-Cohen Matthew Karau Monday 10am - 12pm Trinity College Dublin MSc. Multimedia Systems Spring 2003
Reading: Artistic Practice in the Network • Networks, Bodies, Symbols • Katherine Hayles - “Bruno Latour’s “quasi-object” animate vs. inanimated object (instead a single category) • Accessories • Yukiko Shikata - extending the self wireless devices - become extensions of our personality • Urban Spaces • Knowbotic Research - looking at urban spaces and manifesting their activity in a shared installation both physical and web-based • Simple Networks • Victor Vina - BOX project - • Connected open system Any Thoughts?
RF /IR Communication • What is RF/IR Communication? • RF Comm: Types • How can we use it? • Examples • What has it been used for?
What is IR Communication? • IR = InfraredRadiation • Examples of IR devices: • Remote Control (TV, Stereo) • Handheld Devices (Using IrDA protocolo to send messages - Palm, Mobile Phone) • Sensing devices (breaking beams,burglar alarms)
What is RF Communication? • RF = Radio Frequency Radio Wave = Electromagnetic wave with different frequencies Radio Receiver = Tuning to a specific frequency you can pick up a specific signal. • FM Radio = example 91.5 megahertz • AM Radio = example 535 kilohertz • Examples of bands: • AM radio - 535 kilohertz to 1.7 megahertz • Short wave radio - bands from 5.9 megahertz to 26.1 megahertz • Citizens band (CB) radio - 26.96 megahertz to 27.41 megahertz • Television stations - 54 to 88 megahertz for channels 2 through 6 • FM radio - 88 megahertz to 108 megahertz • Television stations - 174 to 220 megahertz for channels 7 through 13
What is RF Communication? Con’t • Examples of other bands: • Garage door openers, alarm systems, etc. - Around 40 megahertz • Standard cordless phones: Bands from 40 to 50 megahertz • Baby monitors: 49 megahertz • Radio controlled airplanes: Around 72 megahertz, which is different from... • Radio controlled cars: Around 75 megahertz • Wildlife tracking collars: 215 to 220 megahertz • MIR space station: 145 megahertz and 437 megahertz • Cell phones: 824 to 849 megahertz • New 900-MHz cordless phones: Obviously around 900 megahertz! • Air traffic control radar: 960 to 1,215 megahertz • Global Positioning System: 1,227 and 1,575 megahertz • Deep space radio communications: 2290 megahertz to 2300 megahertz
RF/IR Communication: Types • Transmitter/Receiver • Separate modules for each function (IR, RF) • Example - r/c car - controller and receiver on car • IR Example: remote control toy • Transceiver • One module for both functions - transmit and receive (example mobile phone) • IR Example: PALM Pilot, computer port • Half-Duplex Mode • Data can move in two directions, but not at the same time (example walkie-talkie watch) • Full-Duplex Mode • Data can move at the same time in two directions (example telephone, serial, mobile phone, LAN, Infrared) Half-duplex transmitter/receiver Half-duplex transceiver Full-duplex diagram
RF/IR: How can we use It? • RF is great for simple wireless applications • Replace a serial cable with a wireless module/ IR beam to work away from the computer • Be careful about ranges! • Most wireless serial transmitters have limited range (around 300 feet/90 Meters) / IR 3 ft - 3 inches • Local Devices (Questions?) • What are advantages of not being tethered to a computer? • What relationships exist between information and context? • What does wireless add to electronics and networks? Glolab RF Modules www.glolab.com RadioMetrix Transceiver www.radiometrix.co.uk
IR Communication: Schematics • Connecting IR Transmitters/Receivers to Basic Stamp II • Example using 555 timer IC
RF /Infrared: What has it been used for? • 2 Project Examples • One2One - wireless flower • Flower connected to wireless receiver, gets signal from computer and blooms when user’s girlfriend/boyfriend is online • Transparent Headphones - IR communication • IR sends distance info between • Two pairs of headphones
RF Communication: Schematics • Hacking an RC Car Transmitter with a Basic Stamp II