Saturday, February 27, 2010

RFID Applications

There are n-Number of applications where RFID shall be used, few of them are mentioned below:


  • Temperature/Voltage/Humidity/Vibrations/Shocks/Motion/Weight/RPM.. Monitoring System* (Active)
  • Inventory management (Passive/active)
  • Volumetric Follow-up (Active)
  • Asset Tracking System (Active)
  • Asset Management System (Passive)
  • Automated Meter Reading (Active)
  • Anti Theft System (Active)
  • Visitor Management (Active/Passive)
  • Vehicle Tracking System (Active)
  • Parking Management System (Active/Passive)
*Indicates that its a process patented system.

RFID Regulatory Body

The radio frequency (RF) spectrum is a scarce and shared resource, used nationally and internationally, and subject to a wide range of regulatory oversight. The International Telecommunication Union (ITU) is a specialized agency of the United Nations which plays the same role internationally.

Most of the countries allow usage of 866MHZ and 2.4 GHZ bandwidth with the regulated transmitting power freely.
Regulatory differences are based on following points:
Usage of channel
Primary service
Secondary service
Cannot interfere with primary service
Cannot claim protection of interference from primary service
Can claim protection of interference from other secondary users
Industrial, Scientific, & Medical (ISM) Bands
Narrowband or Spread Spectrum
Power level
Duty cycle

RFID Basics- Receivers

Readers (interrogators) can be at a fixed point such as
Entrance/exit
Point of sale
Warehouse

Readers can also be
mobile -- tethered,
hand-held, or wireless

RFID System Selection

Ask yourself before going to any RFID System:
How far?
What is the range that your application requires? This gives you a fair idea about the selection of RFID Type ACTIVE or a PASSIVE.
How fast?
At what intervals you require the data in your system?
How many?
How many items are supposed to be tagged? Volume determines whether to go for RFID or not.
How much?
What is the Loss that is happening because of the existing operational dependency and How much operational efficiency can be gained using RFID, which generates ROI.
Attached to and surrounded by what?
what is the item that is supposed to be tagged and surrounded by what kind of environment?

RFID Basics- Tag Types

Basic Types:

üActive
Tag transmits radio signal
Battery powered memory, radio & circuitry
High Read Range (upto 1 KM*)
üPassive
Tag reflects radio signal from reader
Reader powered
Shorter Read Range (4 inches - 15 feet)

*Range mentioned is in open area, due to obstacles signal strength will reduce based on the type of obstacle.

RFID Basics- Tags

What is RFID? -- The Tags

Tags can be read-only or read-write
Tag memory can be factory or field programmed, partitionable, and optionally permanently locked
Bytes left unlocked can be
rewritten over several Times
Tags can be attached to

almost anything:

pallets or cases of product
vehicles
company assets or personnel
items such as apparel,
luggage, laundry
people, livestock, or pets
high value electronics such
as computers, TVs, camcorders

RFID Basics

What Constitutes an RFID System?

One or more RF tags
Two or more antennas
One or more interrogators
One or more host computers
Appropriate software