Name: mobile phone hanyu pinyin: sh ǒ u j Θ θ English: cellular, mobile phone supplementary note: handset, combined set, short for mobile phone. [Edit this paragraph] Introduction to mobile phones. Mobile phones are commonly called mobile phones, mobile phones and flashlights in Japan, Hongkong and Taiwan Province, and also called mobile phones in the early days. They are a kind of portable telephone terminals that can be widely used. At present, the so-called second generation mobile phones (2G) are the most widely used in the world, mainly GSM and CDMA. They are all in digital format. Besides voice communication, they can also send and receive short messages (SMS), multimedia messages (MMS) and wireless application protocol (WAP). GSM is the most popular in Chinese mainland and Taiwan Province province, and CDMA and PHS mobile phones are also very popular. At present, the whole industry is in the process of migrating to the third generation mobile phone (3G). Generally, the appearance of a mobile phone should include at least one LCD screen and a set of buttons (some touch-screen phones reduce buttons). In addition to typical telephone functions, some mobile phones also include PDA, game machine, MP3, camera, photography, recording, GPS and other functions, and there is a trend to develop to PDA with mobile phone functions. The microphone and earphone of the telephone and the corresponding microphone and receiver are all installed on one handle. Formerly known as mobile phones, handheld devices and mobile phones, they are portable telephone terminals that can move in a large range. [font style = "font-size:13px"] Mobile phones have become popular consumer goods and indispensable items in people's lives. Due to the aging of electronic components, design defects, improper use of mobile phones, different environments, falling, water and other reasons, all kinds of failures will occur, which means that the society needs a large number of mobile phone maintenance personnel. Repairing mobile phones is expensive and has a large profit margin. Therefore, learning mobile phone maintenance technology is beneficial to the country and the people, and mastering mobile phone maintenance technology may change your life! [/font][ Edit this paragraph] Development history 1G The first generation mobile phone (1G) refers to analog mobile phones, which appeared in Hong Kong, the United States and other film and television works in the 1980s and 1990s. The first person to develop a mobile phone was Dr. Cooper from Motorola, USA. Due to the limitation of battery capacity and the development of analog modulation technology, such as huge antenna and integrated circuit, this mobile phone has a square appearance and can only be moved, but not portable. Many people call this kind of mobile phone "brick" or "Black King Kong". There are many formats of this kind of mobile phone, such as NMT, AMPS, TACS, etc., but frequency division multiplexing can only be used for voice communication, with unstable reception effect, insufficient confidentiality and insufficient wireless bandwidth. In this case, the mobile phone is similar to a simple radio duplex station, the call is locked on a certain frequency, and you can use FM radio to eavesdrop on the call. The 2G second generation mobile phone (2G) is also the most common mobile phone. Usually, these mobile phones use very mature standards such as PHS, GSM or CDMA, with stable call quality and appropriate standby time. In the second generation, in order to meet the needs of data communication, some intermediate standards are also supported on mobile phones, such as GPRS supporting MMS service, WAP service for Internet service, and various Java programs. 3G 3G, the abbreviation of English 3rdGeneration, refers to the third generation mobile communication technology. Compared with the first generation of analog mobile phones (1G) and the second generation of GSM, CDMA and other digital mobile phones (2G), the third generation of mobile phones generally refers to a new generation of mobile communication systems that combine wireless communication with multimedia communication such as the Internet. It can handle images, music, video streams and other media forms, and provide a variety of information services including web browsing, teleconference, e-commerce and so on. In order to provide this service, the wireless network must be able to support different data transmission speeds, that is, in indoor, outdoor and driving environments, it can support at least 2Mbps (megabits per second), 384kbps (kilobytes per second) and 144kbps respectively. Future mobile phones Future mobile phones will focus on security and data communication. On the one hand, strengthening the protection of personal privacy, on the other hand, strengthening the research and development of data services will introduce more multimedia functions. Mobile phones will have more computing power and become personal information terminals, not just the functions of calling and short messages. Mobile phones will be more intelligent, miniaturized, safe and multifunctional. At present, the most widely used mobile phones in the world are GSM and CDMA. In Chinese mainland and Taiwan Province Province, GSM is the most popular, and CDMA and PHS mobile phones are also very popular. These are the so-called second generation mobile phones (2G). They are all in digital format. Besides voice communication, they can also send and receive short messages (SMS), multimedia messages (technology) and wireless application protocol (WAP). [Edit this paragraph] Mobile phone type As the name implies, mobile phone type refers to the external type of mobile phone. At present, the commonly used classification is to divide mobile phones into folding (single screen, double screen), upright, sliding, rotary and so on. Single-screen folding mobile phone means that the mobile phone is a flip phone. Only when the cover is opened can you see the main display screen or buttons, and there is only one screen, so this kind of mobile phone is called a single-screen flip phone. At present, there is also a dual-screen flip phone on the market, that is, there is an auxiliary display screen on the flip, which is usually relatively small and can generally display functions such as time, signal, battery and incoming number. Vertical mobile phone means that the screen and buttons of the mobile phone are on the same plane, and the mobile phone has no flip cover. The main feature of upright mobile phone is that it can directly see the content displayed on the screen. Slide-type slide-type mobile phone mainly means that the mobile phone can only see the whole body by pulling. Some models can only see the keys by sliding the lower cover; Others can only see the keyboard by pulling up the screen part. To some extent, the slide phone is an extension and innovation of the flip phone. Wristwatch mobile phone is mainly a mobile phone with the same hand as a watch. Its design is compact and its function is the same as that of ordinary mobile phones. The rotating type is similar to the sliding type, and the most important thing is that you can see the keyboard [Edit this paragraph] after 180 rotates. Business mobile phone, as its name implies, is a mobile phone product targeting business people or people working in state organs and units. Business mobile phones are popular because of their powerful functions. Industry experts pointed out: "A good business mobile phone should not only help users achieve fast and smooth communication, but also complete business activities efficiently." Camera phone A camera phone is a kind of mobile phone, that is, a mobile phone with built-in camera function. The first camera phone in the world was J-SH04 made by Sharp Corporation of Japan in June 5438+065438+ 10, 2000. As expected, this camera phone uses CMOS image sensing module (referred to as CMOS), because CMOS is more power-saving than CCD image sensing module used in digital cameras at that time. Let the battery of the mobile phone not run out quickly because of using the camera. With the improvement of people's health level and the extension of population life, the proportion of the elderly in the population is increasing. The elderly, who account for nearly one third of the population, need their own mobile phones, which is simple to operate. After Celot first launched the mobile phone for the elderly, many manufacturers followed suit and developed their own brands of mobile phones for the elderly. Practical functions: big screen, big font, big ringtone, big buttons, Datong voice; Convenient life: professional software (visual, simple menu and clear structure), one-button dialing, money checking, flashlight, hearing aid, phone book reading, short message reading, incoming call reading and dialing) not only has the functions of improving the quality of life of the elderly: broadcasting radio, Beijing opera and opera, calling for help with one button (calling for help with high decibel after pressing the button), but also calling the designated number for help. ), daily recipes (preferably online download updates), grocery list. Music mobile phone Music mobile phone actually focuses on music playing function in addition to the basic functions of mobile phone (making phone calls, sending text messages, etc.). ). It is characterized by good sound quality, lasting music playing time and shortcut keys for music playing. At present, the better music mobile phones are Nokia XM series and Sony Ericsson WALKMAN series, and other brands have also set foot in this kind of mobile phones. Game mobile phone game mobile phone, that is, mobile phone with more emphasis on game function. The feature is that there are buttons specially set for games or buttons convenient for games on the fuselage, and the screen is generally not small. For example, Nokia N-GAGE platform mobile phone (Nokia N8 1). Invisible mobile phone Invisible mobile phone is a high-end smart handheld computer phone. Besides its super business function and Lian Bi handwriting, as the name implies, its "invisible" function is the most sought after. The so-called "invisibility", first, calls and short messages can be answered and received at will, and those who don't want to answer and receive are filtered out. Second, except the owner himself, no one can see the text messages sent and received, and can't see the call records. Third, important business cards are automatically hidden. The worst thing is not simply an invisible problem, but that others simply can't know whether there are calls, text messages and important business cards. With this mobile phone, even if it is lost, there is no danger of revealing important personal information. Smartphone is a simple formula of "1+1=" PDA+mobile phone = smartphone ". Broadly speaking, smart phone not only has the function of talking on mobile phone, but also has most functions of PDA, especially personal information management based on wireless data communication, browser and email functions. Smart phones provide users with enough screen size and bandwidth, which is not only convenient to carry around, but also provides a broad stage for software operation and content services. Many value-added services can be introduced in this respect, such as: stock, news, weather, transportation, goods, application download, music and picture download, etc. 3C (computer, communication, consumption) smart phone will surely become the new direction of mobile phone development in the future. A few prerequisites for a smart phone: 1, which has all the functions of an ordinary mobile phone and can normally make phone calls, send text messages and other mobile phone applications. 2. Have wireless Internet access capability, that is, support GPRS under GSM network or CDMA 1X, wifi or 3G network under CDMA network. 3. It has the functions of PDA, including PIM (Personal Information Management), schedule, task arrangement, multimedia application and web browsing. 4. Have an open operating system. On this operating system platform, more applications can be installed, so that the functions of smart phones can be expanded infinitely.