Mobile phone Wikipedia
Beyond traditional voice communication, digital mobile phones have evolved to support a wide range of additional services. Contrary to popular misconception, the Federal Aviation Administration (FAA) does not actually prohibit the use of personal electronic devices (including cell phones) on aircraft. By contrast, smartphones generally use a mobile operating system that often shares common traits across devices.
The cell towers are usually interconnected to each other and the phone network and the internet by wired connections. In the earliest mobile phone systems by contrast, all control was done manually; the customer would search for an unoccupied channel and speak to a mobile operator to request connection of a call to a landline number or another mobile. A cellular network mobile phone system gets its name from dividing the service area into many small cells, each with a base station with (for example) a useful range on the order of a kilometer (mile). As well, technical limitations such as antenna efficiency and receiver design limit the range of frequencies a customer unit could use. The critical advantage that modern cellular networks have over predecessor systems is the concept of frequency reuse allowing many simultaneous telephone conversations in a given service area.
In September 2010, the US National Highway Traffic Safety Administration (NHTSA) reported that 995 people were killed by drivers distracted by cell phones. Restrictions on the use of mobile phones are applied in a number of different contexts, often with the goal of health, safety, security or proper functioning of an establishment, or as a matter of etiquette. In Israel, similar phones to kosher phones with restricted features exist to observe the sabbath; under Orthodox Judaism, the use of any electrical device is generally prohibited during this time, other than to save lives, or reduce the risk of death or similar needs. Demand for metals used in mobile phones and other electronics fuelled the Second Congo War, which claimed almost 5.5 million lives. Even so, mobile phones typically have less value on the second-hand market if the phones original IMEI is blacklisted. The petition is part of a joint effort by New York Attorney General Eric Schneiderman and San Francisco District Attorney George Gascón and was directed to the CEOs of the major smartphone manufacturers and telecommunication carriers.
Former systems would cover a service area with one or two powerful base stations with a range of up to tens of kilometers' (miles), using only a few sets of radio channels (frequencies). The race to create truly portable telephone devices began after World War II, with developments taking place in many countries. In addition, they enable multimedia playback and streaming, including video content, as well as radio and television streaming. These include text messaging, multimedia messaging, email, and internet access (via LTE, 5G NR or Wi-Fi), as well as short-range wireless technologies like Bluetooth, infrared, and ultra-wideband (UWB). This radio frequency link connects to the switching systems of a mobile phone operator, providing access to the public switched telephone network (PSTN).
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Depending on the device's type and design, the screen fills most or nearly all of the space on a device's front surface. Mobile processors commonly use heterogeneous multicore architectures, combining cores with different performance and power characteristics so that computational workloads can be distributed according to their processing requirements and energy constraints. With smartphones, NAND flash memory was adopted as it has larger storage capacities and lower costs, but causes longer boot times because instructions cannot be executed from it directly, and must be copied to RAM memory first before execution. The first GSM phones and many feature phones had NOR flash memory, from which processor instructions could be executed directly in an execute in place architecture and allowed for short boot times. Capacity was further increased when phone companies implemented digital networks. Due to bandwidth limitations each cell will have a maximum number of cell phones it can handle at once.
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- This was followed by 3.5G or 3G+ enhancements based on the high-speed packet access (HSPA) family, allowing UMTS networks to have higher data transfer speeds and capacity.
- A study by the London School of Economics found that banning mobile phones in schools could increase pupils' academic performance, providing benefits equal to one extra week of schooling per year.
- Because of these problems, the performance of mobile phone CPUs is often more appropriately given by scores derived from various standardized tests to measure the real effective performance in commonly used applications.
- In February 2014, 93% of mobile developers were targeting smartphones first for mobile app development.
- "Mobile phone" is the most common English-language term, while the term "cell phone" is in more common use in North America – both are in essence shorter versions of "mobile telephone" and "cellular telephone", respectively.
- Mobile processors commonly use heterogeneous multicore architectures, combining cores with different performance and power characteristics so that computational workloads can be distributed according to their processing requirements and energy constraints.
- Feature phones have basic software platforms whilst smartphones have a fully-featured operating system (commonly abbreviated to an OS), with the two most-used platforms being Android and iOS.
Some gtspins casino audio-quality enhancing features, such as Voice over LTE and HD Voice, have appeared and are often available on newer smartphones. Liquid-crystal displays are the most common; others are IPS, LED, OLED, and AMOLED displays. Screen sizes are often measured in diagonal inches or millimeters; feature phones generally have screen sizes below 90 millimetres (3.5 in).
Studies have shown that around 40–50% of the environmental impact of mobile phones occurs during the manufacture of their printed wiring boards and integrated circuits. China has proposed using this technology to track the commuting patterns of Beijing city residents. Enabling contactless payments through NFC-equipped mobile phones requires the co-operation of manufacturers, network operators, and retail merchants. A pilot project in Bali was launched in 2011 by the International Finance Corporation and an Indonesian bank, Bank Mandiri. Soon afterwards, other media content appeared, such as news, video games, jokes, horoscopes, TV content and advertising. Mobile phones are used for a variety of purposes, such as keeping in touch with family members, for conducting business, and in order to have access to a telephone in the event of an emergency.
Software
Feature phones have basic software platforms whilst smartphones have a fully-featured operating system (commonly abbreviated to an OS), with the two most-used platforms being Android and iOS. The exact number of cycles depends on factors such as charging habits, operating temperature, and battery management systems. The small speakers can also be used to listen to digital audio files of music or speech or watch videos with an audio component, without holding the phone close to the ear. Because of these problems, the performance of mobile phone CPUs is often more appropriately given by scores derived from various standardized tests to measure the real effective performance in commonly used applications.
Software
- Due to bandwidth limitations each cell will have a maximum number of cell phones it can handle at once.
- Additionally, short-range Wi-Fi infrastructure is often used by smartphones as much as possible as it offloads traffic from cell networks on to local area networks.
- The exact number of cycles depends on factors such as charging habits, operating temperature, and battery management systems.
- The first GSM phones and many feature phones had NOR flash memory, from which processor instructions could be executed directly in an execute in place architecture and allowed for short boot times.
- The typical lifespan of a mobile phone battery is approximately two to three years, although this varies based on usage patterns, environmental conditions, and overall care.
- SIM and R-UIM cards may be mixed together to allow both GSM and CDMA networks to be accessed.
- In 2001, the third-generation (3G) was launched in Japan by NTT DoCoMo on the WCDMA standard.
Most early content for mobile phones tended to be copies of legacy media, such as banner advertisements or TV news highlight video clips. There are a huge variety of apps, including video games, music products and business tools. The first mobile news service, delivered via SMS, was launched in Finland in 2000, and subsequently many organizations provided "on-demand" and "instant" news services by SMS. A common data application on mobile phones is Short Message Service (SMS) text messaging.
Smartphones are defined by their advanced computing capabilities, which include internet connectivity and access to a wide range of applications. Mobile phone technology has progressed significantly since its origins, evolving from large car-mounted systems to compact, handheld devices. Furthermore, mobile phones offer satellite-based services, such as navigation and messaging, as well as business applications and payment solutions (via scanning QR codes or near-field communication (NFC)). The Motorola Razr V3 and LG Chocolate are two examples of devices that were popular for being fashionable while not necessarily focusing on the original purpose of mobile phones, i.e. a device to provide mobile telephony. Screen time, the amount of time using a device with a screen, has become an issue for mobile phones since the adaptation of smartphones. As of 2007, some hospitals had banned mobile devices due to a common misconception that their use would create significant electromagnetic interference.
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Handsets with more advanced computing ability through the use of native software applications are known as smartphones. Low-end mobile phones are often referred to as feature phones and offer basic telephony. Additionally, short-range Wi-Fi infrastructure is often used by smartphones as much as possible as it offloads traffic from cell networks on to local area networks. The automation systems can control the "hand off" of a customer handset moving between one cell and another so that a call in progress continues without interruption, changing channels if required. In developed countries, smartphones have largely replaced earlier mobile technologies, while in developing regions, they account for around 50% of all mobile phone usage. This ensures it can be applied to mobile Internet access, VoIP, video calls, and sending large e-mail messages, as well as watching videos, typically in standard-definition quality.