Welcome To The World Of PhonesPresentation Transcript
SURVEY OF PHONES
In 1876, at the age of 29, Alexander Graham Bell invented his telephone. In 1877, he formed the Bell Telephone Company
TELEPHONE LANDLINE CELLULARS GSM CDMA 3G
The telephone (from the Greek words tele (τηλέ) = far and phone (φωνή) = voice) is a telecommunications device that is used to transmit and receive sound (most commonly speech), usually two people conversing but occasionally three or more. It is one of the most common household appliances in the world today. Most telephones operate through transmission of electric signals over a complex telephone network which allows almost any phone user to communicate with almost anyone
A traditional landline telephone system, also known as "plain old telephone service" (POTS), commonly handles both signaling and audio information on the same twisted pair of insulated wires: the telephone line. Although originally designed for voice communication, the system has been adapted for data communication such as Telex, Fax and Internet communication. The signaling equipment consists of a bell, beeper, light or other device to alert the user to incoming calls, and number buttons or a rotary dial to enter a telephone number for outgoing calls. A twisted pair line is preferred as it is more effective at rejecting electromagnetic interference (EMI) and crosstalk than an untwisted pair.
Cost is less than the cellulars
Better voice quality
Provides services like fax,internet,ITS
Used in security services
Can’t be used in emergency as it is a fixed line
Global System for Mobile Communication
During the early 1980s, analog cellular telephone systems were experiencing rapid growth in Europe, particularly in United Kingdom, but also in France and Germany. The Europeans realized this early on.
GSM (Global System for Mobile communications) is an open, digital cellular technology used for transmitting mobile voice and data services. GSM differs from first generation wireless systems in that it uses digital technology and time division multiple access transmission methods. GSM satellite roaming has also extended service access to areas where terrestrial coverage is not available.
A CDMA handset operates on an in-built hardware, which means that when the customer abandons a particular service, which has been incorporated in the hardware, he would also have to surrender the handset to the service provider or abandon it. Or, if the hardware in the handset gets damaged, the customer will have no other option but to let.
Voice commands: Call Someone,Digit Dial,Voicemail, Missed Calls, Messages, Time & Date
72-chord polyphonic ringtone & MP3 ringtone support
MMS Send and Receive messages with text, sounds, photos or videos
1.3 megapixel CMOS Camera with flash and business card reader
LCD dual mode for self-portraits
Mini SD external memory port to store pictures, videos, sounds and MP3
Supports Reliance Mobile World
Internet Access through Reliance Netconnect
3G cellular technology will bring wireless broadband data services to your mobile phone. Boasting speeds from 144Kbps (roughly three times faster than a 56K dial-up modem connection) to 2.4Mbps (close to cable-modem speed), 3G networks let you speed through Web pages, enjoy streaming music video, watch on-demand video programming, download and play 3D games, and videoconference with your fellow chatterers. While the interface is undoubtedly different on a cell phone, the experience of surfing, downloading, and streaming stands to be very close to that of a broadband connection on a computer.
Remember those telltale twisty antennas on the roofs of cars in the 1980s? Those cool customers on their car phones were using Advanced Mobile Phone Service, or AMPS.
This first-generation analog network may have been cutting edge at the time, but it soon became notorious for its iffy call quality.
Even worse, anyone with a police radio scanner can easily eavesdrop on AMPS calls, which travel through the air without any scrambling or encryption.
AMPS still is available today on handsets from some phone vendors, but it is largely fading as a technology.
3G service can be defined as a network with reliable Internet speeds higher than 144 kilobits per second (Kbps).
The 3G system used by AT&T and T-Mobile, called UMTS/HSDPA (Universal Mobile Telephone System with High Speed Data Packet Access), lets you make voice calls and surf the Net at the same time. It also has better voice quality and promises Internet speeds up to a megabit, if you're data-happy.
Rolling out the new networks was very expensive, and customers had to be sold on the services.
Furthermore, the move also involved technological constraints. Carriers had to bridge the gap between slow-as-molasses 2G service and zippy 3G with "2.5G" network enhancements.
In operation a couple years now, 2.5G networks let you download ring tones, listen to short audio clips, send multimedia messages (MMS), or surf the Web, albeit slowly.
These services include GPRS, which is capable of transmitting and receiving data at an average of about 30Kbps to 40Kbps, or a little slower than standard 56K dial-up service and EDGE, another GSM enhancement that manages about 90Kbps on an average day, or almost twice as fast as dial-up.