RFID Review /
Bluetooth
ENGR 475 – Telecommunications
Harding University
December 5, 2006
Jonathan White
Outline
What you need to know about RFID
 Bluetooth
 Applications
 Future
 Technical Specifications

• Algorithms
• Air Interface
• Security Concerns
RFID Review
RFID – Radio Frequency
Identification.
 Idea:

• Use low cost tags to identify objects

Benefits:
• Line of sight isn’t required (as in UPC
Codes).
• Much faster inventorying of objects.
• Enables each item to be uniquely
identified.
RFID Review

3 types of tags:
• Active: Have a battery, are always able to
transmit and receive, very large, long range,
very expensive.

Example: Airplane controllers
• Semi-Active: Have a battery, but they only
transmit when in an RF field. They are large
and fairly expensive.

Example: Toll tags
• Passive: No battery, receive power from only
the RF field, very small, very cheap, small
range.

Example: Entry key fobs, Exxon SpeedPass,
EPCGlobal tags.
EPC

Electronic Product Code.
• A replacement for UPC
• Has all the data of a UPC plus other
fields.
• Some fields can be used to store
variables.
• Some fields can be used to uniquely
identify each object.
• Many interesting applications.
EPC Details



Low Range: 20 feet
Low Cost: 5 cents
Low Power requirements:
• Near field: Under 10 cm or so, tag acts like
the opposite side of a transformer, and it can
receive more power.
• Far field: From .5 feet to 20 feet, tag uses
backscattering to reflect a modulated RF field
to the receiver.

Operates in the 900 MHz region.
• Unlicensed, limited by the government.
Bluetooth


Designed in Sweden in 1994.
The goal was to design one interface for
devices to connect and exchange
information wirelessly.
• This would aid in the elimination of all the
cables that are proliferating all around us.
• Not designed to provide power, however.
• Also, Bluetooth was originally designed to be
short range and secure, but this is not
necessarily true now.
Bluetooth Applications



Wireless Cell phone handsets
Wireless controllers (Wii)
Wireless computer connections
• Most common: keyboard, mouse, printer

For remote controls where IR was used.
• Better range and accuracy.


PDA’s, Calculators
Transfer of files in an Ad Hoc Network.
• If you don’t have a WiFi network available.
Bluetooth Applications
Future of Bluetooth

Bluetooth has a good future:
• Data rates of 3 Mbps
• Better security
• Better range.
This will allow Bluetooth TVs and
video projectors.
 The goal is to make an unwired
society.

• But, you still need power.
Technical Specs

Bluetooth operates in the 2.4 GHz range.
• Unlicensed, same band that certain wireless
phones, garage door openers, and baby
monitors use.

Bluetooth devices typically operate at
around .1 Watts.
• Much less than the 3 Watts that a typical cell
phone operates at.

Maximum range is supposed to 100
meters.
• This can be extended to a mile with antennas.
Technical Specs

Bluetooth can connect up to 8
devices.
• 1 master, 7 slaves with about a 10
meter radius.

Bluetooth uses spread spectrum
frequency hopping.
• There are 79 potential frequencies a
device can transmit on, so this should
help eliminate collisions.
Technical Specs

Devices constantly scan for a new
Bluetooth connection.
• This lets them know what master is
controlling them, and whether or not
another device should be added to the
group.

Since this connection is automatic,
security is a large problem for
Bluetooth.
• Bluetooth viruses, bluejacking, blue
bugging.
Conclusion
The use of Bluetooth will be
expanded in the coming years.
 Good for a wire replacement.
 It won’t replace WiFi or cellular
networks.

• It’s impact on Telecommunications is
very secondary.