GPS Basic Information System

GPS or Global Positioning System is a fully functional Global Navigation Satellite System. This system uses an artificial constellation of 24 medium Earth orbit satellites. These satellites transmit microwave signals, thus enabling a GPS receiver to determine its location, speed, direction and time. This system was developed by United States Department of Defense and was named as NAVSTAR GPS which was given by Mr. John Walsh. NAVSTAR is not an acronym, as is widely believed.

This satellite constellation is managed by United States Air Force 50th Space Wing. The cost is approximately 750 US dollars every year, including the maintenance cost, replacement, research and development. After shoot down of Korean Air Lines Flight 007 in the year 1983, a directive was issued which made the GPS available for civilian use and has been used extensively since then. It has become a very useful tool for making maps, surveying landscapes, commerce and many scientific uses. It also provides time reference which can be used in many applications which include study of earthquake and telecommunication network synchronization.

A GPS receiver simply calculates the distance between itself and three more GPS satellite. Each satellite has an atomic clock in it continually transmits certain data containing its exact time, location of the transmitting satellite and the almanac. The receiver then measures the reception time of the signal. Thus the distance to each satellite is known. Knowing three such distances, a trilateration is formed. By using a fourth satellite, need for a clock at receiver is avoided.

The Global Positioning System is used in a variety of Military and Civilian Applications. It allows soldiers find their objectives in a dark or completely unfamiliar territory and coordinate troop movement and supplies. GPS receivers which military personnel use are called Commanders and Soldier Digital Assistants. A combination of GPS and communication through radio enables real time vehicle tracking.

It is also used in marking targets as hostile and enables the precision guided munitions to allow them engage these targets with high accuracy. Air to Ground roles of military aircrafts use GPS to find targets. GPS also allows targeting for military weapons like ICBMs, Cruise missiles, precision guided missile. Artillery based projectiles are embedded with GPS receivers and can withstand forces up to 12,000G. These are used for 155 mm Howitzers. Any Downed pilot can be easily located if he has GPS receiver. It is widely used by military for reconnaissance and mapping. Some GPS satellites also have nuclear detonation detectors.

GPS helps civilians a lot in surveying and navigation. Its ability to calculate local speed and orientation is extremely useful. Time transfer is possible because of its capability to synchronize clock. A widely used example of use of GPS is CDMA digital cell phone. Each base uses a GPS timing receiver to synchronize the codes with different base stations and thus making it easy inter-cellular hand off and thus support emergency phone calls and other many applications. GPS equipment has also revolutionized tectonics by measuring the fault motion during earthquakes.

The two GPS developers, Ivan Getting and Bradford Parkinson have received national academy of Engineering Charles Stark Draper prize during year 2003. Roger L Easton received National Medal for technology on February 13, 2006. Other similar tracking systems are Beidou, which has been developed by China and is proposed to be expanded into COMPASS; Galilieo, which is been developed by European Union along with many other countries like India and China; GLONASS, which is been developed by Russia is fully available in partnership with India; IRNSS is India`s proposed regional system and QZSS which has been proposed by Japan. Read more...

Technology Blurs Lines Between TV and Computers

In the future, the home entertainment center will probably be replaced by more of a home information center. The home information center would blend access to information and entertainment in such a way as to make it possible to access movies, listen to music, make video phone calls or normal phone calls, play video games, surf the Internet, enjoy virtual reality, read and answer email, and utilize a variety of productivity software programs all from the same room in your home. In short, the home computer and the home entertainment system will become one.

There has been technology capable of doing all of these things on the market for years. They're generally marketed as media center PC's or other as other similar names. The most recent mainstream product that attempts to make this marriage of the computer and the home entertainment center is Intel's Viiv chip set running higher end versions of Microsoft's Windows Vista operating system. The Viiv technology can act as a TV receiver and Windows Vista can manage video in the form of digital video recording.

There have been a couple of impediments to getting Americans to invest in home information centers in the past. Historically, Americans have wanted to keep the easy to use home entertainment system components in the living room, while sequestering the relatively difficult to use home computer systems to the home office or study. As computer systems have gotten easier to use, people seem to be less interested in maintaining this boundary, but nonetheless there still is that boundary because of older prejudices. The other impediment is the high price of these systems- a factor that's even worse when you consider how quickly computer systems become obsolete!

One development that has probably helped to bridge the gap between home computer systems and home entertainment systems is the Digital Video Recorder. The Digital Video Recorder helps to break down this prejudice because it is essentially a computer, yet it's easier to use than many of the home entertainment system components of the past.

One product that brings the home computer system into the living room under the guise of a DVR is the Monolith Media Center. The Monolith Media Center is marketed as a DVR, but when you look at the details of what it can do, it becomes very obvious that it is in fact a home computer with a lot of features added on. The Monolith MC comes with multiple TV tuners that can handle standard definition television as well as HDTV and relies on a free version of an on screen program guide so that no subscription is necessary like with other DVR's such as the TiVo. This device can also play audio through your home stereo system.

The real beauty of the Monolith MC is the amount of control that it gives its users. For example, it can get video just like a normal TV receiver through a TV service provider or it can download video from the Internet or it can play video off of DVD's in its built in DVD player. When recording video from a TV signal it can store that video on its hard drive in standard MPEG-2 format or in the space saving MPEG-4 format. It can also copy video from its hard drive onto DVD's that can then be played on other devices.

The Monolith MC also has full computer capability because it runs the Ubuntu Linux operations system with tons of productivity software, web browsers, and even games. This could be the exact technology needed to bridge the gap between the computer and the TV. Read more...