Martin Marty Cooper (born December 26, 1928 in Chicago, Illinois, USA) was the lead engineer of the Motorola team that developed the handheld mobile phone (as distinct from the car phone). Cooper is the CEO and founder of ArrayComm, a company that works on researching smart antenna technology and improving wireless networks, and was the corporate director of Research and Development for Motorola.
obile phone (also called mobile, cellphone or handphone)[1] is an electronic device used for mobile telecommunications over a cellular network of base stations known as cell sites. Mobile phones differ from cordless telephones, which only offer telephone service within limited range through a single base station attached to a fixed line, for example within a home or an office. 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 smartphones.
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.
In addition to being a telephone, 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.
The first hand held phone was demonstrated by Martin Cooper of Motorola in 1973, using a handset weighing in at two kilos.[2] By the end of 2009, the number of mobile cellular subscriptions worldwide reached approximately 4.6 billion, penetrating the developing economies and reaching the bottom of the economic pyramid.[3]
A Nokia phone with box.
A printed circuit board inside a mobile phone
Main articles: Mobile phone features and Smartphone
All mobile phones have a number of features in common, but manufacturers also try to differentiate their own products by implementing additional functions to make them more attractive to consumers. This has led to great innovation in mobile phone development over the last twenty years.
The common components found on all phones are:
• a SIM card which allows the phone user access to the particular mobile phone operator that they have a subscription with
• a rechargeable battery providing the power source for the phone functions
• an input mechanism and display to allow the user to interact with the phone. The most common input mechanism is a keypad, but touch screens are also found in some high end smart phones.
• basic mobile phone services to allow users to make calls and send text messages.
Low-end mobile phones are often referred to as feature phones, and offer basic telephony, as well as functions such as playing music and taking photos, and sometimes simple applications based on generic managed platforms such as Java ME or BREW. Handsets with more advanced computing ability through the use of native software applications became known as smart phones. The first smartphone was the Nokia 9000 Communicator in 1996 which added PDA functionality to the basic mobile phone at the time. As miniaturisation and increased processing power of microchips has enabled ever more features to be added to phones, the concept of the smartphone has evolved, and what was a high-end smartphone five years ago, is a standard phone today.
Several phone series have been introduced to address a given market segment, such as the RIM BlackBerry focusing on enterprise/corporate customer email needs; the SonyEricsson Walkman series of musicphones and Cybershot series of cameraphones; the Nokia Nseries of multimedia phones, the Palm Pre the HTC Dream and the Apple iPhone.
Other features that may be found on mobile phones include GPS navigation, music (MP3) and video (MP4) playback, RDS radio receiver, alarms, memo recording, personal digital assistant functions, ability to watch streaming video, video download, video calling, built-in cameras (1.0+ Mpx) and camcorders (video recording), with autofocus and flash, ringtones, games, PTT, memory card reader (SD), USB (2.0), infrared, Bluetooth (2.0) and WiFi connectivity, instant messaging, Internet e-mail and browsing and serving as a wireless modem. Nokia and the University of Cambridge demonstrated a bendable cell phone called the Morph.
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2009-04-19, 21:13
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