lithium ion cell Interesting Facts About Cell Phones1

The phone is a wireless, portable, LongRemote Electronic telephone, during travel, it can seamlessly switch the antenna connection from one radio receiving unit to another without interrupting or losing the ongoing call.In addition to the standard voice function of the phone, the latest phone (telefone celular) also has functions such as SMS, MMS, radio, games, email Internet connection, etc, built-in browsing, blog, music (MP3) playback, memo recordingIn camera and camera, ringtone, personal organizer, push-to-Call (PTT), Bluetooth and infrared connections, call registers, streaming video, downloading video, video calls, and also as a wireless modem for a pc that can be connected to the Internet.The power supply in the phone (telefone celular) is obtained from the rechargeable battery, which can be charged from the power supply, USB port or cigarette lighter port in the car.
Nickel Metal hydroxide is the most common battery type and is replaced by lithium due to the "memory effect" (users can charge only when the whole battery runs out)Ion battery without any memory effect.In 1947, AT&T's Bell Lab engineer invented hexagonal cells for the base station, and the phone came into being.This was further developed by Bell Labs in the 1960 s.
During the call process, the channel frequency cannot be automatically changed from one cell (base station coverage area) to another cell (base station coverage area) when the person travels from the area of one cell to the area of the other cell.Amos Joel of Bell Labs invented a breakthrough invention and called it "call transfer" through which, during the same call, the channel frequency can be automatically changed from cell to cell when the mobile user moves from cell to cell.These phones are mainly used in cars because of their large structure.
The first practical mobile phone in AfricaThe handheld vehicle setup was invented by Martin Cooper, general manager of Motorola (communications), who made the world's first handheld phone to call in April 3, 1973The technology of the phone's work depends on the phone operator;However, they all use radio waves that are in contact with cellular sites (base stations.The base station consists of several antennas installed on poles, towers or buildings.Cell sites are distributed between 5 and 8 miles (approximately.
Between 8 to 13 km) each other.
The low-power transceiver from the phone transmits voice and data to the nearest cellular site.During the mobile process, the mobile phone will "switch" the information to other cellular sites.Mobile phone operators use a number of technologies to keep the digital data from mobile phones to mobile phone sites open, and vice versa.
Wireless phone technology starts with zero generation or 0G, grouped under the head called Generation.The current generation is 4g;However, there are still old phones running on 1G, 2G and 3G technology (telefone celular ).2G: GSM, iDEN, D-AMPS, IS-95/cdma one, PDC, PHS, GPRS, HSCSD, WiDEN, cdma 2000 1 xRTT/IS-3G: W-CDMA, UMTS (3GSM), FOMA, TD-CDMA/UMTS-TDD, 1xEV-DO/IS-856, TD-The impact of mobile phone use on human health has always been the focus of the world.
The study conducted by the Danish Institute of Cancer Epidemiology, the National Cancer Institute and the Cancer Institute in Copenhagen did not identify any link between cancer and mobile phone use.However, IARC, an inter-governmental agency that is part of the United Nations World Health Organization (WHO), conducted a study of 4,500 users, it was found that there was a statistically significant link between mobile phone use and tumor frequency.Further research is under way.Mobile phone use and driving is a common phenomenon in the world.
Use of hands is prohibited in some jurisdictionsHold the phone while driving, but allow the hand-Free mobile phone when driving.However, the study found that distraction was caused by the conversation itself;So two handsheld and hands-Free mobile phones lead to road traffic accidents.Further research on the use and driving of mobile phones is underway.
Nokia is currently the world's largest mobile phone manufacturer.Other well-known handset manufacturers in alphabetical order are 3g, Audiovox (now UT Starcom), Benefon, BenQ-Siemens, Fujitsu, high-tech computer company (HTC), Kyocera, LG Mobile, Motorola, NEC, Panasonic (Panasonic), Pantech Curitel, Philips, sports research, Sagem, Sanyo, Sharp, Siemens, Sierra Wireless, SK Teletech, Sony Ericsson, T & A Alcatel, Toshiba and Verizon