Knowing Your Cell Phone

blackberry is the most famous cellphone recently, other than apple i-phone or Nokia or other manufacturer
No one doubts that cell phone is one of the most used consumer electronics worldwide. But have you ever asked yourself how does a cell phone work? What is a cell phone?

The amazing fact about a cell phone is that it is a radio - a very special one. The gurus in the line are Bell (1876), Tesla (1880) followed by Marconi and Bose (late 19th century). It is known that the concept of cell phone was produced by Bell Laboratories with the permission of FCC (Federal Communication Commission), and had everything to do with broadcasting and sending a radio message out over the airwaves.

In cell phone technology cells divide the city, allowing for the facility to be frequently reused throughout the city. Millions can simultaneously avail of it.

In devices that are half-duplex (walkie-talkies and CB radios) two communicators use a single frequency. This means that at a single point of time only one can talk. On the other hand a cell phone being a full duplex tool has two frequencies: one for talking and the other for listening. Thus a real-life conversation can take place. Cell phones glide through 1,664 channels whereas the walkie-talkie group has to be content with only 40. The walkie-talkie and the CB radio respectively reaches out to 1 mile and 5 miles but the cell phones, because of their ability to switch from cell to cell can cover incredible distances, even while driving at top speed. Each cell is approximately 10 square miles.

The cells are usually depicted as hexagons. The unique frequency tiers avoid all possibilities of cross connections. Generally a carrier of cell phone can avail of 832 radio frequencies in a city. Each cell phone uses 395 voice channels (per carrier), that is 56 voice channels per cell. It means 56 persons can simultaneously say hello on the phone. In digital transmission technology the number of channels increases even further. For each cell phone 168 channels is available.

The distinctiveness about cell phones is their low-power transmitters. Most use 2 strengths: 0.6 watts and 0.3 watts. In comparison it is 4 watts for CB radios. The advantage of this is that it can be frequently reused consuming less power. Cell phones are battery operated. The lower the power the smaller the battery. This makes the set handy and light.

For cellular technology a city requires a good number of base stations. This can run into some hundreds of towers. But because of the huge number of users costs per head remain very low. Each carrier has one centre called MTSO or Mobile Telephone Switching Office. Its work is to see to all the connections.

Cell phones each have codes, which enable identification of the phone, its user and its server. When someone tries to reach a phone the first thing is to locate the SID (system identification code) on the control channel, that is find out if the phone is within range or not. A message relays no-service when it is out of range. But when the SID is received then the next step is to find out whether the call is within its own home zone or not. The phone also tracks the location of the phone called on a database. Thus the MTSO knows the cell of the called number and caller. Communication is transmitted through the control channel and it is this link that activates the phone being called and calling.

These are the facts of a cell phone as explained for a layman. It is always advisable to know at least the basics of a cell phone since it has become an integral part of our life.

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Source: Free Articles Autor: robertoms

Motorola Evoke QA4 mobile phone

Motorola Evoke QA4 mobile phone now official.

We first saw this phone around blogosphere waiting for an official announcement from Motorola almost two months ago, now Motorola finally made it in public with Motorola Evoke QA4 embracing social media right at the touch of your finger tips. The new slider handset comes with 2.8 -inch touch screen WQVGA 240×400 display with on screen QWERTY keyboard combined with the normal keypad on slide. This also features a 2.0 Megapixel camera phone with 5x digital zoom, CDMA 800/1900/1700/2100, Diversity 1900MHz and 2100 MHz EVDO Rev A network bands and modes, internal 256 MB memory expandable via microSD, aGPS and Bluetooth.


“We understand the importance of having a mobile phone that helps you stay connected simply and seamlessly with your friends and family, whether you prefer to talk, text or network,” said Mark Shockley, corporate vice president and general manager, Motorola Mobile Devices. “Motorola Evoke offers the cutting-edge convenience and instant gratification of a full touch-screen, intuitive online browsing and the ability to stay plugged in on your terms.”

Qualcomm upbeat on smartphone market

TAIPEI (Reuters) - Qualcomm is seeing strong demand for higher-end smartphones despite a weak economy and expects promising growth from the issue of 3G licenses in China, a senior executive at the world's largest maker of cell phone chips said.

Some chipmakers and PC vendors are pinning hopes on fast-growing sales of feature-jammed smartphones to help insulate them from the worst effects of the global economic slowdown, which is sapping demand for personal computers and other hi-tech gadgets.

"Consumer demand for higher-end smartphones remains strong as the demand for wireless Internet, multimedia, and value-added services continues to grow," Jing Wang, a Qualcomm executive vice president, said on Friday in an e-mailed response to Reuters' questions on the outlook for the cell phone and cell phone-chip markets.

"While inventories have contracted, global 3G adoption is continuing to grow as subscribers migrate from second-generation to third-generation networks and manufacturers are shipping more 3G devices this year than last year," the executive said.

Credit Suisse said in a report in February the global smartphone market will grow to 204 million units in 2011 from 141 million units in 2008.

Wang, who is in-charge of Qualcomm's business in the Asia Pacific, Middle East and Africa regions, said Qualcomm will continue to support the growth of Chinese companies in the development of 3G CDMA networks, devices, and applications.

"The issuance of 3G licenses in China is a significant development that presents an exciting opportunity for growth," he said.

The number of CDMA subscribers (including CDMA2000, WCDMA and TD-SCDMA) in China is expected to increase to 211 million in 2013 from 30 million in 2008, he said, citing data from a research house.

China's government has worked hard to develop its homegrown TD-SCDMA 3G standard to promote its own industries and avoid hefty royalties demanded by companies behind the world's most widely accepted 3G standards, WCDMA and CDMA 2000.

Qualcomm currently has license agreements with more than 30 companies based in China, including 10 new agreements executed over the past 12 months, Wang said, without identifying them.

Qualcomm is a major client of TSMC, the world's biggest contract chipmaker, and its chips help power smartphones sold by Taiwan's HTC Corp, which expects sales in China to double this year.

When asked if Qualcomm will place more new orders to TSMC later this year, Wang said: "Any improvement in market conditions that would drive increased volumes of Qualcomm's chipset shipments would also be expected to drive increased volume for our suppliers."

(US$1=T$33.8)

(Reporting by Baker Li, Editing by Ken Wills and Muralikumar Anantharaman)