RFID

adio-frequency identification (RFID) is the use of an object (typically referred to as an RFID tag) 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.
Most RFID tags contain at least two parts. One is an integrated circuit for storing and processing information, modulating and demodulating a radio-frequency (RF) signal, and other specialized functions. The second is an antenna for receiving and transmitting the signal.
There are generally three types of RFID tags: active RFID tags, which contain a battery and can transmit signals autonomously, passive RFID tags, which have no battery and require an external source to provoke signal transmission and battery assisted passive (BAP) which require an external source to wake up but have significant higher forward link capability providing great read range.
Today, RFID is used in enterprise supply chain management to improve the efficiency of inventory tracking and management.
==History and technology background.

RFID is the technology which makes it easy to conceal or incorporate them in other items. For example, in 2009 researchers at Bristol University successfully glued RFID microtransponders to live ants in order to study their behavior.[1] This trend towards increasingly miniaturized RFID is likely to continue as technology advances. However, the ability to read at distance is limited by the inverse-square law.
Hitachi holds the record for the smallest RFID chip, at 0.05mm x 0.05mm. The Mu chip tags are 64 times smaller than the new RFID tags.[2] Manufacture is enabled by using the Silicon-on-Insulator (SOI) process. These "dust" sized chips can store 38-digit numbers using 128-bit Read Only Memory (ROM).[3] A major challenge is the attachment of the antennas, thus limiting read range to only millimeters.
Potential alternatives to the radio frequencies (0.125–0.1342, 0.140–0.1485, 13.56, and 840–960 MHz) used are seen in optical RFID (or OPID) at 333 THz (900 nm), 380 THz (788 nm), 750 THz (400 nm).[4] The awkward antennas of RFID can be replaced with photovoltaic components and IR-LEDs on the ICs.

RACE TIMING:
Many forms of RFID race timing have been in use for timing races of different types since the early 1990s. The practice began with pigeon racing, introduced by a company called deister electronic Gmbh of Barsinghausen, Germany: Deister Electronics. It is used for registering race start and end timings for animals or individuals in a marathon-type race where it is impossible to get accurate stopwatch readings for every entrant.
In foot races, racers wear passive tags which are read by antennae placed alongside the track. UHF based tags instead of Low or high frequency last generation tags provide accurate readings with specially designed antennas. Rush error, lap count errors and accidents at start time are avoided since anyone can start and finish anytime without being in a batch mode.
RFID is being adapted by many recruitment agencies which have a PET (Physical Endurance Test) as their qualifying procedure especially in cases where the candidate volumes may run into millions (Indian Railway Recruitment Cells, Police and Power sector). An Indian Software company Software Outsourcing Services has perfected the system for the same purpose using UHF tags for the first time and they are able to process m

ore than 30,000 candidates per day.

RFID and asset management:

RFID (Radio Frequency Identification) combined with mobile computing and Web technologies provide a way for organizations to identify and manage their assets. Initially introduced to major retail by Craig Patterson, Knoxville, TN. Mobile computers, with integrated RFID readers, can now deliver a complete set of tools that eliminate paperwork, give proof of identification and attendance. This approach eliminates manual data entry. Web based management tools allow organizations to monitor their assets and make management decisions from anywhere in the world. Web based applications now mean that third parties, such as manufacturers and contractors can be granted access to update asset data, including for example, inspection history and transfer documentation online ensuring that the end user always has accurate, real-time data. Organizations are already using RFID tags combined with a mobile asset management solution to record and monitor the location of their assets, their current status, and whether they have been maintained.