3G 3G TECHNOLOGY Mr.M
Nov 16, 2014
3G
3G TECHNOLOGY
Mr.M
WHAT IS 3G TECHNOLOGY?●NEXT GENERATION OF WIRELESS TECHNOLOGY THAT TRANSMITS WIRELESS DATA UPTO 2 MEGABITS PER SECOND AND MAKES INTEGRATION OF●VOICE●DATA●VIDEO
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How 3G is different from 1G & 2G?●G1 was the basic analog radio systems that established the first cellular radio infrastructure. ●G2 Supports fax, short messaging & roaming between network operations.●G3 will do all of this and more it will handle instant messaging, worldwide service, etc
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3G RELEASE●The first 3G network released in Japan, Oct. 1, 2001. ●For now it’s offered in a 30-mile radius of Tokyo for a trial period●This new service will allow users to receive data at six to 40 times faster than current speeds, making fast mobile Internet access and video downloads possible.
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FOCUS ON TECHNOLOGY●The early mobile phones used first-generation technology, which was analog, circuit-based, narrowband, and suitable only for voice communications.●Commercial wireless devices have used second-generation technology, which is digital, circuit-based, narrowband, and suitable for voice and limited data communications
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3G STANDARD●3G technology comprises three primary standards: ● W- CDMA (wideband code-division multiple access), ● CDMA2000, ● TD-CDMA (time-division CDMA).● Each standard is based on an upgrade path for at least one of today’s primary wireless interfaces: ● TDMA (time-division multiple-access),● GSM(Global system for mobile communication)● CDMA(Code division for multiple access
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3G categories●The first category includes the basic 3G phones used for talking and will store all their information on the network.●The second category will support video-streaming. ●More sophisticated models will be information centers which let users download information from the Internet and store data on the device
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Cellular Access TechnologiesThere are three common technologies used by cell-phone networks :●Frequency division multiple access (FDMA) ●Time division multiple access (TDMA) ●Code division multiple access (CDMA)
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FDMA ●FDMA puts each call on a separate frequency. ●only one subscriber at any given time is assigned to a channel.●The channel therefore is closed to other conversations until the initial call is finished, or until it is handed-off to a different channel●A “full-duplex” FDMA transmission requires two channels, one for transmitting and the other for receiving. ● FDMA has been used for first generation analog systems.
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TDMA●TDMA improves spectrum capacity by splitting each frequency into time slots. ● TDMA allows each user to access the entire radio frequency channel for the short period of a call. ● Other users share this same frequency channel at different time slots. ● The base station continually switches from user to user on the channel. ●TDMA is the dominant technology for the second generation mobile cellular networks.●A narrow band that is 30 kHz wide.
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How does CDMA work?●Enables a number of mobile phone users to talk simultaneously in the same area and in the same frequency band ●The cdma technique is also known as a 'spread spectrum' system as the digital code spreads the call across the spectrum bandwidth to transmit the signal.● Uses a special digital code for each user. This code is combined and transmitted with the voice signal of the individual user across the entire spectrum.●CDMA increases spectrum capacity by allowing all users to occupy all channels at the same time
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Capabilities of CDMA0NE●The next phase of cdmaOne enables 144 kbps packet data in a mobile environment.● Other features available are a two-fold increase in both standby time and voice capacity. All of these capabilities will be available in an existing cdmaOne 1.25 MHz channel.
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●The next phase of cdmaOne evolution will incorporate and support ● all channel sizes (5 MHz, 10 MHz, etc.),● provide circuit and packet data rates up to 2 Mbps, ● incorporate advanced multimedia capabilities, and● include a framework for advanced 3G voice services, including voice over packet and circuit data.● cdmaOne uses frequency ranges around 800MHz and 1900MHz.
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CDMA2000 ●It divides available radio spectrum into highly efficient information carriers based on a special coding scheme. It is characterized by high capacity, small cell radius and spread spectrum radio transmission. ●Enable mobile systems to offer data throughputs of 2 MBit/sec and beyond.●Allows simultaneous access to several voice, video and data services at once.
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WCDMA●Wide band or broad band is considered to include data rates from 64 Kbps to 2 Mbps.●Wideband channels can carry multiple signals in the same piece of frequency spectrum. ●wideband CDMA uses nearly 5MHz per carrier●WCDMA allows simultaneous access to several voice, video and data services at once.
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The Advantages of Wider Bandwidth●As the signal is spread over a large frequency-band, the Power Spectral Density is getting very small, so other communications systems do not suffer from this kind of communications. ●Random Access can be dealt with, as a large number of codes can be generated a large number of users can be permitted.● The maximal number of users is interference limited.●Without knowing the spreading code it is impossible to recover the transmitted data.
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How does GPRS work●GPRS builds Internet Protocol (IP) data handling technology into current GSM mobile networks. ●series of 'packets', are routed over several paths through the network, rather than as a continuous bit-stream over a dedicated dial-up connection. ●In a packet-based call, network resources used when data is transferred.
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BASIC OF CELLULAR TECH:●In a cellular network, cells are generally organized in groups of seven to form a cluster. ● There is a “cell site” or “ base station” at the center of each cell, which houses the transmitter/receiver antennae and switching equipment. ● The size of a cell depends on the density of subscribers in an area: for instance, in a densely populated area, the capacity of the network can be improved by reducing the size of a cell or by adding more overlapping cells. Mr. M
This increases the number of channels available without increasing the actual number of frequencies being used. All base stations of each cell are connected to a central point, called the Mobile Switching Office (MSO), either by fixed lines or microwave. The MSO is generally connected to the PSTN (Public Switched Telephone Network):
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mobile telephone switching office fig.
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3G AT HOME AND IN WORKPLACEManage our finances.On a tourist vacation.Conference meeting through mobile.Maintenance Engineer can download demonstration video that guides him through the repair process. Mobile job interview.
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APPEARANCE OF 3G Mr. M
Disadvantages of 3G●High Prices to help cover the initial demand and fixed cost. ● Needs more towers the high density requires towers to be closer together. ●Availability to consumers.● One of the biggest disadvantages is that is would be a big risk for entrepreneurs to take because the cost are high, and the start slow.
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THREATS TO 3G●The US Defense Department, government agencies, schools, and health facilities are using some of the spectra identified which are suitable for 3G.●After terrorist attacks, the US military is not likely to give up its share of potential 3G spectrum for videoconferencing on mobile phones.●High costs.
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Conclusion● 3G technologies is a combination of high-speed wireless access w/ internet protocol(IP) Based services will bring the world to your fingertips. ●we will be able to check emails, book holidays, hold video conferences or download video clips of the latest film, instantly & simply from our mobiles.
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