Biometric Technology

BIOMETRICS refers to  the automatic   identification of  a  person based   on    his physiological / behavioral  characteristics. This method of  identification is preferred for various reasons;the person to be identified is required to be physically present at the point of  identification; identification based on biometric techniques obviates the need to remember a password or carry a token. With the increased use of computers or  vehicles of  information technology, it is necessary to restrict access to sensitive or personal  data.  By  replacing PINs, biometric   techniques  can   potentially  prevent unauthorized access to fraudulent use of ATMs, cellular phones, smart cards, desktop PCs,  workstations, and computer networks. PINs  and passwords may be forgotten, and token based methods of  identification  like passports and driver’s  licenses  may be forged, stolen,  or lost .Thus biometric   systems  of   identification  are   enjoying a renewed interest. Various  types of biometric systems are being used  for real–time identification ; the most popular  are  based  on   face   recognition   and  fingerprint matching. However there are other biometric systems that utilize iris and retinal scan, speech,  facial  thermo grams, and hand geometry.

    A  biometric  system  is  essentially  a pattern   recognition system,  which   makes  a personal identification by determining  the authenticity of a specific physiological or behavioral  characteristics possessed by the  user. An  important issue in designing a practical  system is to determine  how an  individual is  identified.  Depending on the context, a  biometric system can be either a verification (authentication) system or an  identification system. There  are  two  different  ways  to  resolve  a   person’s   identity :  Verification  and Identification. Verification  ( Am  I  whom I claim  I  am ?)   involves  confirming  or denying a person’s  claimed identity. In Identification one has to establish a person’s identity  (whom am  I?). Each one  of these approaches  has its own complexities and could probably be solved best by a certain biometric system.

    Biometrics  is rapidly evolving technology, which is  being  used  in forensics such as criminal identification and prison security, and has the potential to be used in a large range of civilian application areas . Biometrics can be used transactions conducted via telephone and  Internet (electronic  commerce and  electronic banking) . In  automobiles, biometrics can replace keys with key -less entry devices.

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GLOBAL POSITIONING SYSTEM

The Global Positioning System, usually called GPS, is the only fully-functional satellite navigation system. A constellation of more than two dozen GPS satellites broadcasts precise timing signals by radio to GPS receivers, allowing them to accurately determine their location (longitude, latitude, and altitude) in any weather, day or night, anywhere on Earth.

United States Department of Defense developed the system, officially named NAVSTAR GPS (Navigation Signal Timing and Ranging GPS), and the satellite constellation is managed by the 50th Space Wing at Schriever Air Force Base. Although the cost of maintaining the system is approximately US$400 million per year, including the replacement of aging satellites, GPS is available for free use in civilian applications as a public good.

GPS has become a vital global utility, indispensable for modern navigation on land, sea, and air around the world, as well as an important tool for map-making, and land surveying. GPS also provides an extremely precise time reference, required for telecommunications and some scientific research, including the study of earthquakes.

In late 2005, the first in a series of next-generation GPS satellites was added to the constellation, offering several new capabilities, including a second civilian GPS signal called L2C for enhanced accuracy and reliability. In the coming years, additional next-generation satellites will increase coverage of L2C and add a third and fourth civilian signal to the system, as well as advanced military capabilities.

The Wide-Area Augmentation System (WAAS), available since August 2000, increases the accuracy of GPS signals to within 2 meters (6 ft) [1] for compatible receivers. GPS accuracy can be improved further, to about 1 cm (half an inch) over short distances, using techniques such as Differential GPS (DGPS).

Global Positioning System) A satellite-based radio navigation system run by the U.S. Department of Defense. It was designed so that signals from at least four satellites would be on the horizon at all times, which is sufficient to compute the current latitude, longitude and elevation of a GPS receiver anywhere on earth to within a few meters. The first GPS satellite was launched in 1978.

In six different orbits approximately 12,500 miles above the earth, the system's 24 MEO satellites circle the earth every 12 hours. The satellites do nothing more than constantly transmit their current time based on atomic clocks and current location. A monitoring network on the ground tracks the satellites and uplinks data for synchronization. The system uses four frequencies in the L-band from 1.2 to 1.6GHz .

Whether installed in vehicles or carried by hand, a GPS receiver calculates the distance to the satellites by comparing the times the transmitted signals were sent with the times they were received. By knowing the precise locations of the satellites at a given moment, the receiver uses triangulation, the navigation technique of ship captains for centuries, to pinpoint its own location.

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Mobile ProcessorIn

In January of 2000, Transmeta Corporation introduced the Crusoe processors, an x86-compatible family of solutions that combines strong performance with remarkably low power consumption. As might be expected, a new technology for designing and implementing microprocessors underlies the development of these products. As might not be expected, the new technology is fundamentally software-based: the power savings come from replacing large numbers of transistors with software.

The Crusoe processor solutions consist of a hardware engine logically surrounded by a software layer. The engine is a very long instruction word (VLIW) CPU capable of executing up to four operations in each clock cycle. The VLIW’s native instruction set bears no resemblance to the x86 instruction set; it has been designed purely for fast lowpower implementation using conventional CMOS fabrication. The surrounding software layer gives x86 programs the impression that they are running on x86 hardware.

The software layer is called Code Morphing software because it dynamically “morphs” x86 instructions into VLIW instructions. The Code Morphing software includes a number of advanced features to achieve good system-level performance. Code Morphing support facilities are also built into the underlying CPUs. In other words, the Transmeta designers have judiciously rendered some functions in hardware and some in software, according to the product design goals and constraints. Transmeta’s Code Morphing technology changes the entire approach to designing microprocessors. Finally, decoupling the hardware design from the system and application software that use it frees hardware designers to evolve and eventually replace their designs without perturbing legacy software..

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