What is 3G and 4G ?

3G in Pakistan:

3G is the third generation mobile communication technology , refers to support high-speed data transmission cellular mobile communications technology. 3G services can simultaneously transmit voice and data information, third generation mobile phones generally speaking, is the next generation mobile communication system, such as wireless communications and multimedia communications with the Internet . It can handle multiple forms of media images, music, video streaming and other services including web browsing, conference calls, e-commerce and other information services.  3G refers to wireless communications and international Internet and other next-generation mobile communication systems combining multimedia communications, currently there are three 3G standards: CDMA2000 , WCDMA , TD-SCDMA .
3G peak theoretical downlink speeds of up to 3.6Mbit / s (one that 2.8Mbit / s), but also the peak uplink speeds of up to 384kbit / s. Not like the Internet, said the 2G per second, of course, it is impossible to instantly download a movie is completed.

4G in Pakistan:

The fourth-generation mobile communication standard mobile phone, referring to the fourth generation of mobile communication technology , foreign language abbreviations : 4G. The techniques include TD-LTE and FDD-LTE two formats (strictly speaking, 4G is only 3.5G, LTE despite being advertised as 4G wireless standards, but it actually has not been 3GPP recognized as the International Telecommunication Union as described in the next generation wireless communication standard IMT-Advanced, and therefore in the strict sense has not yet reached its 4G standard. upgraded version of the LTE Advanced is only just meet the ITU requirements for 4G). 4G is a 3G and WLAN in one, and quickly transfer data, high quality audio, video and images. 4G can download speeds of more than 100Mbps, faster than current home broadband ADSL (4 megabytes) 20 times, and be able to meet almost all users for wireless service requirements. In addition, 4G can be DSL and cable modems are not covered by local deployment, and then extended to the entire region.Obviously, 4G has incomparable superiority.

4G support these phones: Samsung Note2, N7108D, Sony M35t, ZTE U9815, Cool 8736, HTC 8088, Huawei G716, Amagatarai Touch 1, Hisense X6t so on.

Table compares 4G and 3G systems
Feature	4G	3G
Service Features	Integration of data and voice, multimedia	Priority to voice
Internet access	Multiple heterogeneous access	Single access
Frequency Range	2-8GHz, 800MHz	1.6-2.5GHz
Rate	20-100Mbit / s	385kbit/s-2Mbit/s
Bandwidth	100 + MHz	5-20MHz
Access	OFDM	WCDMA/ TD/CDMA2000 /WiMAX
Exchange	Packet switching	Packet switching / circuit-switched
IP Performance	IPv6	Multiple versions

Advantages and Defects:

Advantages:

1: The communication speed

As people study the initial purpose is to improve communication 4G cellular phones and other mobile devices speed wireless access to the Internet, and therefore the most impressive 4G communication characteristics than it has faster wireless communication speed.

For comparison from the mobile communication system data rate, only the first generation analog voice services; second generation digital mobile communication system transmission rate is only 9.6Kbps, up to 32Kbps, such as PHS; Third Generation Mobile Communication System Data transfer rate up to 2Mbps; while the fourth generation mobile communication system transmission rate up to 20Mbps, the highest you can even reach up to 100Mbps, this rate will be equivalent to about 2009 new cell phone transmission speed of a million times, the third-generation mobile phone transmission 50 times the speed.

2: Network wide spectrum

To make the 4G communication reach 100Mbps transmission, communications operators must be based on 3G communication networks, and research carried out substantial reform in order to make the 4G network communication bandwidth higher than the bandwidth of 3G networks in many cellular systems. According to the research of AT & T 4G communications executives say is estimated that each channel will occupy 100MHz 4G spectrum, the equivalent of W-CDMA 3G network 20 times.

3: Communication flexible

From the strict sense, 4G mobile phone features, they are not simply classified as "phone" category, after all, just a function of the transmission of voice data, one 4G mobile phone only, and therefore the future of 4G phones should be regarded as a small computer from the appearance and style , there will be even more amazing breakthrough, it is conceivable that, eyewear, watches, cosmetic, shoes, and personality in order to facilitate the premise that any one can see the items 4G terminals are likely to be, but people still do not know how should I call it.

Future 4G communication so that people can not only communicate anytime, anywhere, but you can download a two-way transmission of information, pictures, video, of course, can and never met a stranger online-line rally game. Perhaps there was never locked positioning system online nowhere to hide distress, but with the map it accordingly provides the convenience and security compared to, this is simply negligible.

4: Intelligent performance

The higher intelligence of the fourth generation mobile communications, not only in the 4G communication terminal apparatus with intelligent design and operation, such as the scroll operation and the menu will greatly reduce reliance more important 4G phone can imagine many function.

For example 4G phone can remind According to environmental factors, time and other settings in a timely manner at which point the phone's owner do, or should not be doing, 4G mobile phone cinema box office data can be downloaded directly onto PDA, These data can be the ticket, the seats in circumstances indicate that very clear, we can use this information to their own satisfaction with online purchasing movie tickets; 4G phones can be seen as a portable TV, with a view of the game of sports category various live.

5: Compatibility

For 4G communication as soon as possible to be accepted, it features not only a strong consideration, but also should take into account the existing communications, in order to allow more existing users will be able to communicate easily in transition with minimal investment to 4G communications.

Therefore, from this perspective, the future of fourth generation mobile communication system should have global roaming, open interfaces, talk to a variety of networking, terminal diversification and a smooth transition from the second generation features.

6: To provide value-added services

4G communication is not from the foundation of the 3G communications through a simple upgrade of evolution, their core construction technology is simply different, 3G CDMA mobile communication system is mainly based on the core technology, and 4G mobile communication system technology as a positive deposit multitasking frequency technology (OFDM) most attention, it may be implemented using such technology such as a wireless local loop (WLL), Digital Audio Broadcasting (DAB), etc. The wireless communication value-added services; but considering the 3G communication transitional, the fourth generation mobile communication system using OFDM is not only just a technology in the future, CDMA technology in the fourth generation mobile communication systems, and OFDM technologies complement each other in order to play a greater role, and even the future first Fourth generation mobile communication systems will have a new integration technologies such as OFDM / CDMA generation, digital audio broadcasting previously mentioned, in fact, it really is the use of technology OFDM / FDMA integration technology, the same technology is the use of a combination of the two.

So the next OFDM as the core technology in the fourth generation mobile communication systems will combine the advantages of both technologies, part of the extension will be based on CDMA technology.

7: High quality communications

Although the third generation mobile communication system can achieve a variety of multimedia communications, for the future fourth-generation mobile communication systems are also referred to as "multimedia mobile communications.

Not only to the fourth generation mobile communication applications due to the increase in the number of households, more importantly, it must be transmitted in response to the demand for multimedia, of course, required communication quality. In conclusion, we must be able to accommodate a large number of users market, improve the poor quality of existing communication and achieve high-speed data transmission requirements.

8: High frequency efficiency

Compared to the third generation mobile communication technology , the fourth generation of mobile communication technology use and the introduction of many powerful breakthrough technology in the development of the process, such as some fiber optic communications products company in order to further enhance the width of the wireless Internet backbone bandwidth, the introduction of the level switching technology, which can also cover the different types of communication interfaces , i.e. mainly the use of fourth generation Routing based network architecture.

As the use of several different technologies, so much more effective use of the radio frequency than the second generation and third generation systems.

Estimated according to the most optimistic scenario, the effectiveness of allowing more people to use the same amount of radio spectrum previously do more, and do these things very fast. The researchers say it is possible to achieve download speeds of 5Mbps to 10Mbps.

9: Cheap Cost 

As the 4G communication not only solved the problem of compatibility with 3G communication, so that more users can easily existing communication upgrade to 4G communications, and 4G communication introduces many cutting-edge communications technologies, which ensure that the 4G communication can provide a kind of flexibility is very high system mode of operation, so compared to other technologies, it is much easier to deploy 4G communications quickly; while building 4G communications network system , the communication operators who will consider direct communication infrastructure in 3G networks above, using the method introduced gradually, so that it is possible to effectively reduce the running cost and users.According to the researchers claim that 4G wireless instant communication connectivity fees for certain services will be cheaper than 3G communication.

For people, the future 4G communication does seem very mysterious, and many people think that the fourth generation of wireless communication network system is the most complex technical systems of mankind ever invented. Indeed, the fourth-generation wireless communications network a large number of vexing technical problems in the specific implementation, it probably does not make people feel unexpected and surprising. The fourth generation of wireless communications technology networks and the Internet about the existence of multiple, and it takes several years to resolve.

Defects:

1: Standard multi-

Although in theory, 3G mobile phone users worldwide mobile communications can be carried out, but because there is no uniform international standards, a variety of mobile communication systems are not compatible with each other, to mobile phone users inconvenience. Therefore, the development of fourth generation mobile communication system must first solve the communication system, such as the need for global standardization of unity, and the world's major communications companies would have been in this debate.

2: Technical difficulties

Although the future 4G communication can bring a better tomorrow, has come up, but not universal.According to the research of this technology developers, in order to achieve download speeds of 4G communications also faces a series of technical problems.

For example, how to ensure that floor area, mountains, and other obstacles, such as signal strength in the affected areas vulnerable to such issues. Japan's DoCoMo, said that in order to solve this problem, the company would different coding techniques and transmission technology to be tested. Another technical problem in terms of the existence of the transfer, the phone is easy when it enters the coverage area of another base station from the coverage area of a base station and the network lost contact.

Since the fourth-generation wireless communication network structure is rather complex, this problem is especially pronounced. However, industry experts say they believe that this problem can be solved, but it will take some time.

3: The capacity is limited

People on the future of 4G communications deepest impression than its communication transmission speed will be greatly improved, said its so-called broadband speeds of 100Mbps per second (approximately sec 12.5MB) Theoretically, in 2009 than the latest mobile phones Information 10KB per second transfer rate 1,000 times faster, but the phone's speed will be limited capacity of the communication system, such as system capacity is limited, mobile phone users, the more slowly. According to expert analysis, 4G phones will be difficult to reach its theoretical speed. If you do not increase the speed, 4G mobile phone is being reduced.

4: The market is difficult to digest

Some experts predict that in 10 years, the third generation of mobile multimedia services will communicate to enter the third stage of development, when global coverage of 3G network has been basically completed, more than 25% of the world's population uses the third generation mobile communication systems, third generation technology is still slow to enter the market, by which time the industry is the third generation of technology digestion and absorption, for accepting the fourth generation mobile communication system also requires a process of gradual transition.

In addition, during the transition, if the 4G communication systems because of shortages caused by the delay or the terminal, then known as 5G technology at any time may threaten the profitability of 4G plans at this time 4G long and profitable investment recovery plan will become Abnormal fragile.

5: Facilities Update slow

Before deploying 4G communications network systems, covering most of the world's wireless infrastructure is based on the third generation mobile communication system established, the fourth generation of communications technology if you want to transfer, then many of the world's wireless infrastructure needs experiencing a lot of changes and updates, this is bound to change and update a comprehensive mitigation 4G communication technology into the marketplace speed.

And then, also must require 3G communication terminal can be upgraded to higher speed data transmission and communication to support the 4G terminal 4G data services, that 4G communication terminal to be able to provide timely 4G communications network after completion, can not let production lags communication terminal network construction. But according to some of the facts, the 4G communication technology entered the date of counting of the commercial in 2023, consumers are expected to spend only stable performance of the 4G mobile phone communication.

Other

Because the more powerful phones, and wireless communications networks are becoming increasingly complex, the same communication capabilities increasingly 4G, while its construction and development than the previous system construction will encounter more difficulties and troubles .

For example each new equipment and technology introduced, followed by software design and development must be able to keep pace with timely, in order to make new equipment and technology has been rapidly promoted and applied, but unfortunately still only in the research 4G communication and development stage, specific equipment and techniques used yet fully formed, and therefore the corresponding software developers will encounter difficulties; addition rates and billing is particularly important for the development of 4G mobile data communications market, such as WAP phones After the launch, users spend a lot of time to get connected to information, and the time and charges by way of content so that the user unbearable, so you must carefully study the early fee-based 4G communication systems, in order to facilitate market development.