A mobile phone (handset) is an electronic device that provides services to users. mobile name comes from the Latin word mobilis - “to move” “able to move freely or easily” “able or willing to move freely or easily between occupations, places of residence and social classes” .
Mobile, wireless or cellular phone - a portable, handheld
communications device connected to a wireless network that allows users to make
voice calls, send text messages and run applications.
Mobile phones, Handsets include smartphones and PDAs.
Handsets use several hardware components: Microprocessor, ROM,
RAM, Digital signal processor, Radio module, Microphone and speaker, Hardware
interfaces, LCD display.
Handsets store system data in electronically-erasable
programmable read-only memory (EEPROM), Service providers can reprogram phones
without requiring physical access to memory chips, OS is stored in ROM
(nonvolatile memory), Most handsets also include subscriber identity module
(SIM) cards.
Handsets use embedded processors: Intel, ARM architectures BlackBerry
8700, uses Intel PXA901 chip, iPhone, uses Samsung ARM 1100 chip, Low power use
and code size are crucial, Microprocessor vendors often package all the chip’s
functionality in a single chip (package-on-package) for maximum flexibility.
SIM Cards :
They include their
own microprocessor and 16 KB – 4 MB EEPROM, They come in two sizes, Their
versatility arises from portability of information, SIM card identifies
subscriber to network, Stores personal information, address books, messages,
service-related information.
Memory Cards :
Some handsets include other peripheral memory cards: Compact
Flash, Multimedia Card, Secure Digital, Handsets synchronize with a computer, Nowadays,
computers include slots of various sizes to hold these memory cards.
Handset Operating Systems:
Symbian OS, iPhone OS (an embedded version of OS X), Windows
Mobile, BlackBerry OS, Google Android Platform (based on Linux) With the
exceptions of Symbian and Android, these OSes are proprietary. Telecom carriers
frequently “lock down” handset firmware, OSes to prevent user modifications.
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