1.5 KiB
1.5 KiB
IoT term is used to refer to
- the resulting globlal network of connecting smart objects
- the protocols ...
- ...
required features:
- devices hetereogeneity
- scalability
- data ubiquitous data exchange
- energy-optimized solutions
Backscattering
- allows devices to run without battery
- only available at research level for now
- use radio frequency signals as power source
- two types
- ambient
- rfid
Ambient backscattering
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devices harvest power from signals available in the environment
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they use existing RF signals without requiring any additional
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Performance drawbacks
- low data rate (about 1kbps)
- not suitable for real-time applications that continuously exchange data
- availability of signals
- signal may not be available indoor or not powerful enough
- low data rate (about 1kbps)
RFID backscattering
...
Battery free smart home
- in a smart home there may be a lot of smart devices
- if every one of them has a battery, it's not good for the environment
- we can deploy an RFID reader with multiple antennas that covers all the different rooms
Communication
add scheme slide
RFID tags run EPC Global Standard
- in a smart home we may want less bits dedicated to the tag id and more dedicated to the actual data
- 8 bits for ID
- 6 bits for data
- 4 for CRC
Infrastructure based wireless networks
- base stations connected to wired backbone network
- stations choses the closest base station
- Limits
- when no infrastructure is available
- expensive/inconvenient to setup
- when there is no time to set it up