RFID – Radio Frequency Identification is a technology that is used to uniquely identify an object, animal, or person. RFID is coming into increasing use in industry as an alternative to the bar code. The advantage of RFID is that it does not require direct contact or line-of-sight scanning. An RFID system consists of three components: an antenna and transceiver (often combined into one Reader) and a transponder (the Tag). The antenna uses radio frequency waves to transmit a signal that activates the transponder. When activated, the Tag transmits data back to the antenna. The data is used to notify a programmable logic controller that an action should occur.

Why RFID?

• No need for physical contact between data carrier and the communication device.
• Tags can be used repeatedly.
• Works in harsh environments (compared to bar code, optical scan technologies) withstands extreme temperatures, acid baths etc.
• Low maintenance costs.
• Tags available in a range of types, sizes and materials.
• Simultaneous & multiple tag reads, 10s to 1000s in short time intervals.
• Non-line-of-sight communication makes it possible to read and write Tags in dirty conditions.
• Extremely low error rate.
• Can be read through the human body, clothing and non-metallic materials.

RFID consists of different component like:

Reader – A transmitter/receiver that reads the contents of RFID Tags in the vicinity, also called an "RFID interrogator." The maximum distance between the Reader's antenna and the Tag vary, depending on application.

Tag – An electronic identification device that is made up of a chip and antenna. For reusable applications, it is typically embedded in a plastic housing, and for tracking shipments, it is usually part of a "smart" packaging label. An RFID Tag is an object that can be applied to or incorporated into a product, animal, or person for the purpose of identification and tracking using radio waves. Some Tags can be read from several meters away and beyond the line of sight of the Reader. The Tag contains a unique serial number, but may have other information, such as a customers' account number. There are generally three types of RFID Tags: active RFID Tags, which contain a battery, and passive RFID Tags, which have no battery and Semi-Active RFID Tags which contain a battery but only activates when it is under frequency of Reader.

Host Computer:-Stores the data into database and view real time presentation of an asset with History.

Working principle of RFID Technology?

The antenna enables the chip (data storage) to transmit its identification information to a reader/interrogator. The reader converts the radio waves returned from the RFID tags into digital information and passes it to the computer.

Benefits of RFID

• Automates the entire process.
• Unique Identification - Each RFID tag has a unique serial number that distinguishes among many millions of identically manufactured objects.
• Wireless, non-contact, non-line-of-site.
• Ideally suited for providing low cost remote and instant identification of objects.
• Real time tracking of assets and its content.
• Visibility of location of assets and their tampering history, maintenance history.
• RFID tags can be read through human body, clothing and non-metallic materials.

Application area of RFID

• Corporate offices and industries.
• Supply chain and retail industries.
• Automobile Industries.
• Healthcare and pharmaceuticals.
• Government, Military and Army.
• Commercial Industries.

RFID Future
RFID technology is growing very fast. As technology moves ahead, Tags and readers sizes are reducing with the increase of functionalities.

According to experts, RFID technology represents a new approach towards business with an interaction of computers with wireless technology, sensors and networking.

Smart Dust Tag

• Micro/Nano devices.
• Integrated MEMS +ID+power+RF Antenna.

RFID Sensor Hidden inside Fake Rocks.
U.S. military is developing RFID sensors that will be installed in fake little rocks. These 'rocks' which will be the size of golf balls, will be sent from an aircraft and will detect enemies by 'listening' to them from 20 to 30 meters.

RFID Tags, Antennas and Readers
RFID tag is a microchip combined with an antenna in a compact package. When attached to an object, object will be traced by a reader. Tags Antenna picks up signals from Reader and then returns the signal with some additional data (like unique serial number of other customized information).

Types of Tags 

• Active Tags
• Powered by battery.
• Larger in size and expensive.
• Better identification range and larger capacity.
• Semi-Active Tags
• Uses battery to power microchip but not to communicate with reader.
• These Tags are used for longer range and with more capabilities.
• Passive Tags
• Operate using the power of RFID readers.
• Small and inexpensive, but have a limited range.

RFID Readers
A reader (now more typically referred as an RFID Interrogator), is basically a radio frequency (RF) transmitter and receiver, controlled by a microprocessor or digital signal processor. The reader, using an attached antenna, captures data from tags, then passes the data to a computer for processing.

Types of Readers

• Fixed Readers
• Fixed in a position (for example, beside a conveyor belt in a factory or dock doors in a warehouse). Consists of Antennas connected to it. Antennas communicate with Tags.
• Handheld Reader
• Portable, integrated with an application and used to scan individual items in a warehouse or by mobile workers. Consists of in built Antennas.