Wireless phones receive their signals from towers. A cell contains some individual parts – an amazing circuit board containing the brains of the phone, an antenna, a liquid crystal display (LCD), a keyboard, a microphone, a speaker, and a battery. The circuit board is the heart of the system.Cell Phone Technology is moving in leaps and bounds
The analog-to-digital and digital-to-analog conversion chips can translate the outgoing audio signal from analog to digital and the incoming signal from digital back to analog. The digital signal processor (DSP) is a highly customized processor designed to do signal-manipulation calculations at high speed.
The microprocessor can handle all of the housekeeping chores for the keyboard and display, deal with command and control signaling with the base station and also coordinates the rest of the functions on the board.
The ROM and Flash memory chips give storage for the phone’s operating system and customizable features, such as the phone directory. The radio frequency (RF) and power section can handle power management and recharging, and deal with the hundreds of FM channels. Finally, the RF amplifiers handle signals traveling to and from the antenna.
Cell Phone Technology has been developed and is developing day by day.
Reading the article, you can learn more about the increasing use of different functions of Cell Phone Technology.
The Cell Phone Technology Speaker, Microphone and Battery Backup
Cell phones have very tiny speakers and microphones. It is unbelievable that they can reproduce sound so well. The speaker is about the size of a dime and the microphone is no larger than the watch battery. The watch battery is used by the cell phone’s internal clock chip.
AMPS – Cell Phone Technology
In 1983, the analog cell-phone standard which is called AMPS (Advanced Mobile Phone System) was approved by the FCC and first used in Chicago. AMPS uses a range of frequencies between 824 megahertz (MHz) and 894 MHz for analog cell phones.
A version of AMPS known as Narrowband Advanced Mobile Phone Service (NAMPS) incorporates some digital technology to allow the system to carry about three times as many calls as the original version. Even though it uses digital technology, it is still considered analog. AMPS and NAMPS only operate in the 800-MHz band and do not offer many of the features common in digital cellular service, such as e-mail and Web browsing.
Digital Cell Phones use the same radio technology as analog phones, but in a different way. Analog systems do not fully utilize the signal between the phone and the cellular network — analog signals cannot be compressed and manipulated as easily as a true digital signal. So, many cable companies are switching to digital and so they can fit more channels within a given bandwidth. Digital systems are more efficient.
Digital phones can convert voice into binary information (1s and 0s) and then compress it. This compression allows between three and 10 digital cell-phone calls to occupy the space of a single analog call.
Many digital cellular systems depend on frequency-shift keying (FSK) to send data back and forth over AMPS. FSK uses 2 frequencies, one for 1s and the other for 0s, alternating rapidly between the two to send digital information between the cell tower and the phone. Clever modulation and encoding schemes are required to convert the analog information to digital, compress it and convert it back again while maintaining an acceptable level of voice quality. Digital cell phones have to contain a lot of processing power well.
Cellular Access Technologies
There are 3 common technologies used by cell-phone networks for transmitting information:
- Frequency division multiple access (FDMA)
- Time division multiple access (TDMA)
- Code division multiple access (CDMA)
FDMA puts each call on a separate frequency. TDMA assigns each call a limited time on a designated frequency. CDMA shows a unique code to each call spreading it over the available frequencies. The last part of each name is multiple access. This simply means that more than one user can utilize each cell.
FDMA separates the spectrum into distinct voice channels by splitting it into uniform chunks of bandwidth. FDMA is used mainly for analog transmission. Certainly capable of carrying digital information, FDMA is not considered to be an efficient method for digital transmission.
TDMA Splits a Frequency into Time Slots
In FDMA, each phone uses a different frequency. TDMA is also used as the access technology for Global System for Mobile communications (GSM). However, GSM implements TDMA in a somewhat different and incompatible way from IS-136. GSM and IS-136- two different operating systems work on the same processor, like Windows and Linux both working on an Intel Pentium III. GSM systems use encryption to make phone calls more secure. GSM operates in the 900-MHz and 1800-MHz bands in Europe and Asia, and in the 1900-MHz band in the United States. It is used in digital cellular and PCS-based systems. GSM is also the basis for Integrated Digital System.
Wireless phones which receive their signals from towers. A cell is typically the area (it may be several miles) around a tower in which a signal can be received. Cell phones provide many different functions. Depending on the cell-phone model, you can
- Store contact information
- Make task or to-do lists
- Keep track of appointments and set reminders
- Use the built-in calculator for simple math
- Send or receive e-mail
- Get information (news, entertainment) from the internet
- Play games
- Watch TV, and
- Send text messages
A cell phone Integrates other devices such as PDAs, MP3 players and GPS receivers. A cell phone is a full-duplex device. You can use a frequency for talking and a separate frequency for listening. Both people on the call can talk at once.
Many experts argue that the future of computer technology rests in mobile computing with wireless networking. Mobile computing by way of tablet computers is becoming more popular. Tablets are available on the 3G and 4G networks. 4g network is the fastest network accessing method in India.
Many types of mobile operating systems (OS) are available for smart phones. They are Android, BlackBerry OS, webOS, iOS, Symbian, Windows Mobile Professional (touch screen), Windows Mobile Standard (non-touch screen), and Bada. Among them, the Apple iPhone, and the newest – Android are most popular. Android is a mobile operating system (OS) developed by Google. Android is the first completely open source mobile OS. It means that it is free to any cell phone mobile network.
Peer-to-peer (P2P) file sharing applications are possible on their 3G network. It then became apparent that it would keep any of their users from using their iTunes programs. The users want to find a wi-Fi hotspot to be able to download files.
Future of the Smart Phone
Smart phones will use newer applications and bring revolutionary change in our life the future -using an X-Ray device that reveals information about any location at which you point your phone. Different companies are developing software to take advantage of more accurate location-sensing data. It is amazing to think that the smart phone will use a virtual mouse and be able to click the real world. An example of this is where you can point the phone’s camera while having the live feed open and it will show text with the building and saving the location of the building for use in the future.
Along with the future of a smart phone comes the future of another device. Omnitouch is a device in which applications can be viewed and used on your hand, arm, wall, desk, or any other everyday surface. The device uses a sensor touch interface, which enables the user to access all the functions through the use of touch. It was developed at Carnegie Mellon University. The device uses a projector and camera that is worn on the person’s shoulder, and can only be controlled using fingers.
At last we can say that Cell Phone Technology will surely govern the world and our life will evolve with it.