24-08-2011, 12:04 PM
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1..INTRODUCTION TO CELL PHONES
1.1.HOW IT WAS INVENTED?
Inventor Martin Cooper
Launch year 1973
Company Motorola
Available Worldwide
A mobile phone (also called mobile, cellular phone, cell phone or hand-phone is an electronic device used for full duplex two-way radio telecommunications over a cellular network of base stations known as cell sites
A mobile phone allows its user to make and receive telephone calls to and from the public telephone network which includes other mobiles and fixed line phones across the world. It does this by connecting to a cellular network owned by a mobile network operator. A key feature of the cellular network is that it enables seamless telephone calls even when the user is moving around wide areas via a process known as handoff or handover.
Modern mobile phones also support many additional services, and accessories, such as SMS (or text) messages, email, Internet access, gaming, Bluetooth, infrared, camera, MMS messaging, MP3 player, radio and GPS. Low-end mobile phones are often referred to as feature phones, whereas high-end mobile phones that offer more advanced computing ability are referred to as smart-phones.
The first handheld cellular phone was demonstrated by Martin Cooper of Motorola in 1973, using a handset weighing in at two kilos.
By the end of 2009, only 20 years later, the number of mobile cellular subscriptions worldwide reached approximately 4.6 billion, 370 times the 1990 number, penetrating the developing economies and reaching the bottom of the economic pyramid.
1.2.HOW IT WAS DEVELOPED?
Fig no.1.2
An evolution of mobile phone
The first mobile telephone call made from a car occurred in St. Louis, Missouri, USA on June 17, 1946, but the system was impractical from what is considered a portable handset today
In 1960, the world’s first partly automatic car phone system, Mobile System A (MTA), was launched in Sweden. MTA phones were composed of vacuum tubes and relays, and had a weight of 40kg. In 1962, a more modern version called Mobile System B (MTB) was launched, which was a push-button telephone, and which used transistors in order to enhance the telephone’scalling capacity and improve its operational reliability. In 1971 the MTD version was launched, opening for several different brands of equipment and gaining commercial success.
Martin Cooper, a Motorola researcher and executive is considered to be the inventor of the first practical mobile phone for hand-held use in a non-vehicle setting, after a long race against Bell Labs for the first portable mobile phone. Using a modern, if somewhat heavy portable handset, Cooper made the first call on a hand-held mobile phone on April 3, 1973 to his rival, Dr. Joel S. Engel of Bell Labs.
1..INTRODUCTION TO CELL PHONES
1.1.HOW IT WAS INVENTED?
Inventor Martin Cooper
Launch year 1973
Company Motorola
Available Worldwide
A mobile phone (also called mobile, cellular phone, cell phone or hand-phone is an electronic device used for full duplex two-way radio telecommunications over a cellular network of base stations known as cell sites
A mobile phone allows its user to make and receive telephone calls to and from the public telephone network which includes other mobiles and fixed line phones across the world. It does this by connecting to a cellular network owned by a mobile network operator. A key feature of the cellular network is that it enables seamless telephone calls even when the user is moving around wide areas via a process known as handoff or handover.
Modern mobile phones also support many additional services, and accessories, such as SMS (or text) messages, email, Internet access, gaming, Bluetooth, infrared, camera, MMS messaging, MP3 player, radio and GPS. Low-end mobile phones are often referred to as feature phones, whereas high-end mobile phones that offer more advanced computing ability are referred to as smart-phones.
The first handheld cellular phone was demonstrated by Martin Cooper of Motorola in 1973, using a handset weighing in at two kilos.
By the end of 2009, only 20 years later, the number of mobile cellular subscriptions worldwide reached approximately 4.6 billion, 370 times the 1990 number, penetrating the developing economies and reaching the bottom of the economic pyramid.
1.2.HOW IT WAS DEVELOPED?
Fig no.1.2
An evolution of mobile phone
The first mobile telephone call made from a car occurred in St. Louis, Missouri, USA on June 17, 1946, but the system was impractical from what is considered a portable handset today
In 1960, the world’s first partly automatic car phone system, Mobile System A (MTA), was launched in Sweden. MTA phones were composed of vacuum tubes and relays, and had a weight of 40kg. In 1962, a more modern version called Mobile System B (MTB) was launched, which was a push-button telephone, and which used transistors in order to enhance the telephone’scalling capacity and improve its operational reliability. In 1971 the MTD version was launched, opening for several different brands of equipment and gaining commercial success.
Martin Cooper, a Motorola researcher and executive is considered to be the inventor of the first practical mobile phone for hand-held use in a non-vehicle setting, after a long race against Bell Labs for the first portable mobile phone. Using a modern, if somewhat heavy portable handset, Cooper made the first call on a hand-held mobile phone on April 3, 1973 to his rival, Dr. Joel S. Engel of Bell Labs.
