Fact about cell phones

Mobile (cell phone) is a wireless, portable, long-distance telephony electronics, which for the trip may well change connections antenna, a radio reception cell to another cell radio reception, or drop without losing the call ongoing.

In addition to the normal function of a voice phone, the latest cellular phones (cell phone) have features like text messaging SMS, MMS for multimedia messaging, radio, games, Internet connectivity for e-mail , browse, read blogs, music (MP3) playback, the note recording, a function of the cameras and camcorders, melodies, personal organizers, Push-to-Talk (PTT), Bluetooth and infrared connectivity, call records, video streaming, downloading video, video call, and also serve as wireless modems for PCs that can be connected to the Internet.

The power in a mobile phone (cell phone) comes from rechargeable batteries, which can be recharged in the network, a USB port or a port for the cigarette lighter in a car. Nickel Metal Hydride are the most common types of batteries, which due to the "memory effect" (the user can be recharged only when the battery is drained across the front) was replaced by lithium ion batteries, which do not suffer any memory effect .

Mobile phones (cell phone) came into existence because of the invention of hexagonal cells in 1947, the base stations by engineers from Bell Labs, AT & T. This was developed during the decade of 1960 by Bell Labs. During a call, the channel frequency can not be changed automatically to a cell (coverage area of the base station) to another cell (coverage area of the base station) as the person who traveled from the area of one cell to the another area of the cell. Joel Amos of Bell Labs invented a breakthrough invention and called it as `` a call handoff in which the channel frequency can be changed automatically from one cell to another cell, during the same call, and the user of a mobile traveled another cell to cell. Due to its heavy construction, these phones are mainly used in the automotive industry.

The first practical cell phone in a vehicle not fix, and that could be hand held, was invented by Martin Cooper, the Director (Communications Division) Motorola, who made the world `s first hand mobile phone (cell phone ) call on April 3, 1973.

The technology by which the mobile phone (cell phone) works depends on the mobile phone operator, however, all of whom use electromagnetic waves of radio, which are in contact with a cell site (base station). The base station is made up of several antennas, which are mounted on a pole, tower or building. Cell sites are spread over a distance of 5 to 8 miles (about 8 to 13 kilometers) from the others. The low-power transceiver from the handset transmits voice and data to the nearest cell site. During the move, the handset "handoff" information to other cells site. The mobile operators use many technologies to maintain the smooth flow of digitized data from cell phone to cell site, and vice versa.

The wireless telephone technologies are grouped into heads known as generations, starting from scratch generation or 0G. The current generation happening is 4G, however, there are old mobile phones (cell phone), which still operate in 1G, 2G and 3G technologies. The wireless phone technology used in each generation are as shown below:

0 G: PTT, MTS, IMTS, AMTS, OLT, BAT, Autotel / PALM ARP

1 G: NMT, AMPS / TACS / ETACS, Hicap, CDPD, Mobitex, DataTac

2 G: GSM, iDEN products, D-AMPS, IS-95/cdmaOne, CDP, CSD, PHS, GPRS, HSCSD, WiDEN, CDMA2000 1xRTT/IS-2000 EDGE (EGPRS)

3 G: W-CDMA, UMTS (3GSM), FOMA, TD-CDMA/UMTS-TDD, 1xEV-DO/IS-856, TD-SCDMA, GAN (AMU), HSPA, HSDPA, HSUPA, HSPA +, HSOPA

4 G: UMB, UMTS Revision 8 (LTE), WiMAX

Frequency bands: SMR, cellular, PCS

The impact of mobile phone (cell phone) use on human health has been of great concern throughout the world. Research studies in Copenhagen, the Danish Institute of Cancer Epidemiology, the National Cancer Institute and the Institute of Cancer Research, do not establish any link between cancer and cell phone use. However, an intergovernmental agency, IARC (International Agency for Research on Cancer), which are part of the World Health Organization of the United Nations, conducted a survey of 4500 users and found a statistically significant relationship between the use phone the tumor cell and frequency. Further investigation is going on.

Mobile (cell phone) use and driving is a common phenomenon throughout the world. Some jurisdictions have banned the use of handheld phones while driving, but allow the hands-free fashion of cellular phone use while driving. However, studies have found that the distraction is caused by the conversation itself, therefore handheld and hands-free cell phones contribute to traffic accidents. More studies on cell phone use and driving are happening.

Nokia Corporation is currently the world `s largest manufacturer of mobile phones (cell phone). Other handset manufacturers, in alphabetical order, are 3G, Audiovox (now UT Starcom), Benefon, BenQ-Siemens, Fujitsu, High Tech Computer Corporation (HTC), Kyocera, LG Mobile, Motorola, NEC, Panasonic (Matsushita Electric) , Pantech Curitel, Philips, Research In Motion, Sagem, Samsung, Sanyo, Sharp, Siemens, Sierra Wireless, SK Teletech, Sony Ericsson, T & A Alcatel, Toshiba, and Verizon.