apsidalkat

Mobile phone

2007-03-07T08:47:00.000-08:00

A mobile or cellular telephone is a long-range, portable electronic device for personal telecommunications over long distances. In addition to the standard voice function of a telephone, current mobile phones can support many additional services such as SMS for text messaging, email, packet switching for access to the Internet, and MMS for sending and receiving photos and video. Most current mobile phones connect to a cellular network of base stations (cell sites), which is in turn interconnected to the public switched telephone network (PSTN) (the exception are satellite phones).

Mobile phones are distinct from cordless telephones, which generally operate only within a limited range of a specific base station. Technically, the term mobile phone includes such devices as satellite phones and pre-cellular mobile phones such as those operating via MTS which do not have a cellular network, whereas the related term cell(ular) phone does not. In practice, the two terms are used nearly

History

2007-02-07T08:48:00.000-08:00

The Mobile phone is one of the most used pieces of equipment today. The concept of using hexagonal cells for mobile phone base stations was invented in 1947 by Bell Labs engineers at AT&T (see History of mobile phones) and was further developed by Bell Labs during the 1960s. Radiophones have a long and varied history that stretches back to the 1950s, with hand-held cellular radio devices being available since 1983. Due to their low establishment costs and rapid deployment, mobile phone networks have since spread rapidly throughout the world, outstripping the growth of fixed telephony

In 1945, the 0G generation of mobile telephones were introduced. OG mobile telephones such as Mobile Telephone Service were not officially categorized as mobile phones, since they did not support the automatic change of channel frequency in the middle of a call, when the user moved from one cell (base station coverage area) to another cell, a feature called "handover."

Mock-up of the "portable phone of the future," from a mid-1960s Bell System advertisement, shows a device not too different from today's mobile telephones.In 1970 Amos Joel of Bell Labs invented "call handoff" that allowed a mobile phone user to travel through several cells during the same conversation. Martin Cooper of Motorola is widely considered to be the inventor of the first practical mobile phone for handheld use in a non-vehicle setting. Using a modern, if somewhat heavy portable handset, Cooper made the first call on a handheld mobile phone on April 3, 1973. At the time he made his call, Cooper was working as Motorola's General Manager of its Communications Division.

Fully automatic cellular networks were first introduced in the early to mid-1980s (the 1G generation). The first fully automatic mobile phone system was the 1981 Nordic Mobile Telephone (NMT) system. Until the late 1980s, most mobile phones were too large to be carried in a jacket pocket, so they were usually permanently installed in vehicles as car phones. With the advance of miniaturization and smaller digital components, mobile phones got smaller and lighter.

Manufacturers

2007-01-07T08:49:00.000-08:00

Nokia Corporation is currently the world's largest manufacturer of mobile telephones, with a global market share of approximately 36% in Q4 of 2006.[1] Other mobile phone manufacturers include Apple Inc., Audiovox (now UT Starcom), Benefon, BenQ-Siemens, High Tech Computer Corporation, Fujitsu, Kyocera, 3G, LG, Motorola, NEC, HTC, Panasonic (Matsushita Electric), Pantech Curitel, Philips, Research in Motion, Sagem, Samsung, Sanyo, Sharp, Siemens, SK Teletech, Sony Ericsson, T&A Alcatel, and Toshiba. There are also specialist communication systems related to, but distinct from mobile phones, such as Professional Mobile Radio

Etiquette

2006-12-07T08:51:00.000-08:00

Mobile phone etiquette has become an important issue with mobiles ringing at funerals, weddings, cinemas, and plays. Users often speak at increased volume which has led to places like book shops, libraries, movie theatres, doctors' offices, and houses of worship posting signs prohibiting the use of mobile phones, and in some places installing signal-jamming equipment to prevent usage (although in many countries, e.g., the United States, such equipment is currently illegal). Some new buildings such as auditoriums have installed wire mesh in the walls which prevents any signal getting through, but does not contravene the jamming laws.

Transportation providers, particularly those involving long-distance services, often offer a "quiet car" where phone use is prohibited, much like the designated non-smoking cars in the past. However many users tend to ignore this as it is rarely enforced, especially if the other cars are crowded and they have no choice but to go in the "quiet car". Mobile phone use on aircraft is also prohibited, because of concerns of possible interference with aircraft radio communications, although the airline Emirates have announced plans to allow limited mobile phone usage on some flights. In a similar vein signs are put up in UK petrol stations prohibiting the use of mobile phones due to safety issues. Most schools in the United States have prohibited mobile phones in the classroom due to the high amount of class disruptions that result from their use, and due to the possibility of photographing someone (without consent).

Subscriptions

2006-12-07T08:49:00.000-08:00

In the UK, the number of cell numbers has surpassed the number of people. There will be over four hundred million cell phone users in China by 2008. Luxembourg has the highest mobile phone penetration rate in the world, at 164% in December 2005. In Hong Kong the penetration rate reached 117% of population in September 2004. The total number of mobile phone subscribers in the world was estimated at 2.14 billion in 2005. Around 80% of world's population have mobile phone coverage as of 2006. This figure is expected to increase to 90% by the year 2010.

At present, Africa has the largest growth rate of cellular subscribers in the world. African markets are expanding nearly twice as fast as Asian markets. The availability of Prepaid or pay as you go services, where the subscriber does not have to commit to a long term contract, has helped fuel this growth on a monumental scale, not only in Africa but on other continents as well.

On a numerical basis, India is the biggest growth market adding about 6 million cell phones every month. With 156.31 million cell phones, teledensity in the country is still low at 17.45% and country expects to reach 500 million subscribers by end of 2010.

All European nations and most Asian and African nations have adopted GSM. In other countries, such as the United States, Australia,India, Japan, and South Korea, legislation does not require any particular standard, and GSM coexists with other standards, such as CDMA and iDEN.

Some cellular systems are pay as you go, where top-ups can be purchased and added to a phone unit, so there is no monthly bill. Many are "pay monthly", where a bill is issued every month for the amount of calls and text messages made.

Mobile phone culture or customs

2006-11-29T10:12:00.000-08:00

In fewer than twenty years, mobile phones have gone from being rare and expensive pieces of equipment used by businesses to a pervasive low-cost personal item. In many countries, mobile phones now outnumber land-line telephones, with most adults and many children now owning mobile phones. In the United States, 50% of children own mobile phones. It is not uncommon for young adults to simply own a mobile phone instead of a land-line for their residence. In some developing countries, where there is little existing fixed-line infrastructure, the mobile phone has become widespread. According to the CIA World Factbook the UK now has more mobile phones than people .

With high levels of mobile telephone penetration, a mobile culture has evolved, where the phone becomes a key social tool, and people rely on their mobile phone address book to keep in touch with their friends. Many people keep in touch using SMS, and a whole culture of "texting" has developed from this. The commercial market in SMS's is growing. Many phones even offer Instant Messenger services to increase the simplicity and ease of texting on phones. Cellular phones in Japan, offering Internet capabilities such as NTT DoCoMo's i-mode, offer text messaging via standard e-mail.

The mobile phone itself has also become a totemic and fashion object, with users decorating, customizing, and accessorizing their mobile phones to reflect their personality. This has emerged as its own industry. The sale of commercial ringtones exceeded $2.5 billion in 2004 .

The use of a mobile phone is prohibited in some rail carriagesMobile phone etiquette has become an important issue with mobiles ringing at funerals, weddings, movies, and plays. Users often speak at increased volume which has led to places like bookshops, libraries, movie theatres, doctor's offices, and houses of worship posting signs prohibiting the use of mobile phones, and in some places installing signal jamming equipment to prevent usage (although in many countries, e.g. the United States, such equipment is illegal). Transportation providers, particularly those doing long-distance services, often offer a "quiet car" where phone use is prohibited, much like the designated non-smoking cars in the past. Mobile phone use on aircraft is also prohibited, because of concerns of possible interference with aircraft radio communications, although the airline Emirates have announced plans to allow limited celluar phone usage on some flights. Most schools in the U.S prohibit cell phones due to the high amount of class disruptions due to their use, and due to the possibility of photographing someone (without consent).

Camera phones and videophones that can capture video and take photographs are increasingly being used by companies like Scoopt to cover breaking news. Stories like the London Bombings, the Indian Ocean Tsunami and Hurricane Katrina have been reported on by camera phone users on photo sharing sites like Flickr.

In Japan, cellular phone companies provide immediate notification of earthquakes and other natural disasters to their customers free of charge. In the event of an emergency, disaster response crews can locate trapped or injured people using the signals from their mobile phones; an interactive menu accessible through the phone's Internet browser notifies the company if the user is safe or in distress.

Features

2006-11-07T08:52:00.000-08:00

Invented in 1997, the camera phone is now 85% of the market. In a recent Weekend America interview on public radio, Philippe Kahn, the inventor of the camera phone, discusses its social impact and how it connects people around the world. Mobile phones also often have features beyond sending text messages and making voice calls—including Internet browsing, music (MP3) playback, memo recording, personal organizers, e-mail, built-in cameras and camcorders, ringtones, games, radio, Push-to-Talk (PTT), infrared and Bluetooth connectivity, call registers, ability to watch streaming video or download video for later viewing, video call and serve as a wireless modem for a PC.

In most countries, including European nations, Japan, Pakistan, Australia, Chile, Colombia, India, Maldives and Israel the person receiving a mobile phone call pays nothing. However, in Hong Kong, Canada, and the United States, one can be charged per minute. In the United States, a few carriers are beginning to offer unlimited received phone calls. For example as of December 2006, Sprint now has 4 plans under "Sprint Free Incoming Plans" section of their website, although the restriction is the receiving phone must be on the Sprint PCS network. For the Chinese mainland, it was reported that both of its two operators will adopt the caller-pays approach as early as January 2007

Technology

2006-10-07T08:54:00.000-07:00

Mobile phones and the network they operate under vary significantly from provider to provider, and nation to nation. However, all of them communicate through electromagnetic microwaves with a cell site base station, the antennas of which are usually mounted on a tower, pole, or building.

The phones have a low-power transceiver that transmits voice and data to the nearest cell sites, usually not more than 5 to 8 miles (approximately 8 to 13 kilometres) away. When the mobile phone or data device is turned on, it registers with the mobile telephone exchange, or switch, with its unique identifiers, and will then be alerted by the mobile switch when there is an incoming telephone call. The handset constantly listens for the strongest signal being received from the surrounding base stations. As the user moves around the network, the mobile device will "handoff" to various cell sites during calls, or while waiting (idle) between calls it will reselect cell sites.

Cell sites have relatively low-power (often only one or two watts) radio transmitters which broadcast their presence and relay communications between the mobile handsets and the switch. The switch in turn connects the call to another subscriber of the same wireless service provider or to the public telephone network, which includes the networks of other wireless carriers. Many of these sites are camouflaged to blend with existing environments, particularly in high-scenery areas.

The dialogue between the handset and the cell site is a stream of digital data that includes digitized audio (except for the first generation analog networks). The technology that achieves this depends on the system which the mobile phone operator has adopted. Some technologies include AMPS for analog, and D-AMPS, CDMA2000, GSM, GPRS, EV-DO, and UMTS for digital communications. Each network operator has a unique radio frequency band.

Albert Einstein

2006-08-26T10:42:00.000-07:00

Albert Einstein was born at Ulm, in Württemberg, Germany, on March 14, 1879. Six weeks later the family moved to Munich and he began his schooling there at the Luitpold Gymnasium. Later, they moved to Italy and Albert continued his education at Aarau, Switzerland and in 1896 he entered the Swiss Federal Polytechnic School in Zurich to be trained as a teacher in physics and mathematics. In 1901, the year he gained his diploma, he acquired Swiss citizenship and, as he was unable to find a teaching post, he accepted a position as technical assistant in the Swiss Patent Office. In 1905 he obtained his doctor's degree.During his stay at the Patent Office, and in his spare time, he produced much of his remarkable work and in 1908 he was appointed Privatdozent in Berne. In 1909 he became Professor Extraordinary at Zurich, in 1911 Professor of Theoretical Physics at Prague, returning to Zurich in the following year to fill a similar post. In 1914 he was appointed Director of the Kaiser Wilhelm Physical Institute and Professor in the University of Berlin. He became a German citizen in 1914 and remained in Berlin until 1933 when he renounced his citizenship for political reasons and emigrated to America to take the position of Professor of Theoretical Physics at Princeton*. He became a United States citizen in 1940 and retired from his post in 1945.After World War II, Einstein was a leading figure in the World Government Movement, he was offered the Presidency of the State of Israel, which he declined, and he collaborated with Dr. Chaim Weizmann in establishing the Hebrew University of Jerusalem.Einstein always appeared to have a clear view of the problems of physics and the determination to solve them. He had a strategy of his own and was able to visualize the main stages on the way to his goal. He regarded his major achievements as mere stepping-stones for the next advance.At the start of his scientific work, Einstein realized the inadequacies of Newtonian mechanics and his special theory of relativity stemmed from an attempt to reconcile the laws of mechanics with the laws of the electromagnetic field. He dealt with classical problems of statistical mechanics and problems in which they were merged with quantum theory: this led to an explanation of the Brownian movement of molecules. He investigated the thermal properties of light with a low radiation density and his observations laid the foundation of the photon theory of light.In his early days in Berlin, Einstein postulated that the correct interpretation of the special theory of relativity must also furnish a theory of gravitation and in 1916 he published his paper on the general theory of relativity. During this time he also contributed to the problems of the theory of radiation and statistical mechanics.In the 1920's, Einstein embarked on the construction of unified field theories, although he continued to work on the probabilistic interpretation of quantum theory, and he persevered with this work in America. He contributed to statistical mechanics by his development of the quantum theory of a monatomic gas and he has also accomplished valuable work in connection with atomic transition probabilities and relativistic cosmology.After his retirement he continued to work towards the unification of the basic concepts of physics, taking the opposite approach, geometrisation, to the majority of physicists.Einstein's researches are, of course, well chronicled and his more important works include Special Theory of Relativity (1905), Relativity (English translations, 1920 and 1950), General Theory of Relativity (1916), Investigations on Theory of Brownian Movement (1926), and The Evolution of Physics (1938). Among his non-scientific works, About Zionism (1930), Why War? (1933), My Philosophy (1934), and Out of My Later Years (1950) are perhaps the most important.Albert Einstein received honorary doctorate degrees in science, medicine and philosophy from many European and American universities. During the 1920's he lectured in Europe, America and the Far East and he was awarded Fellowships or Memberships of all the leading scientific academies throughout the world. He gained numerous awards in recognition of his work, including the Copley Medal of the Royal Society of London in 1925, and the Franklin Medal of the Franklin Institute in 1935.Einstein's gifts inevitably resulted in his dwelling much in intellectual solitude and, for relaxation, music played an important part in his life. He married Mileva Maric in 1903 and they had a daughter and two sons; their marriage was dissolved in 1919 and in the same year he married his cousin, Elsa Löwenthal, who died in 1936. He died on April 18, 1955 at Princeton, New Jersey.

Champion

2005-06-02T01:00:00.000-07:00

Phone card

europe-calling-card.quald.com is dedicated to provide long distance phone card services like international phone cards and prepaid calling cards with best rates and quality connection. Our International calling cards offer the lowest rates for calling to many countries which provide more minutes than ever before.

Now we offer, prepaid phone card Champion.

Champion phone card is a Permanent PIN card with Refill feature and PIN free access option. Low calling rates to many countries with high quality connection. Local Access numbers are available in addition to Toll Free Access. Use Local Access numbers in your area and get the cheapest rates!
Champion phone card features:

Value: 10,15,20,30,50,100,250$
No Connection Fee
Maintenance Fee - No
Rounding - 1 minute
Toll Free Access Numbers - Yes (USA)
Local Access Numbers - Yes (Russia)
Tax - 15%
Pay Phone Charge - 89c
Validity period - Unlimited (Card expired if no refill within 6 months.)
Prompt Languages - English
International Access - this card can be used from USA - Continental

Permanent PIN features:

PIN Free Access! Register your phone number with the card and it is recognized automatically after dialing the Access number, and You don't need to enter a hard-to-remember PIN! Register up to 6 different phone numbers to one account.
Refill pin the card at any time (add more funds).