08-10-2016, 03:42 PM
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ABSTRACT: 4G (also known as Beyond 3G), an abbreviation for Fourth-Generation, is a term used to describe the next complete evolution in wirelesscommunications. A 4G system will be able to provide a comprehensive IP solution where voice, data and streamed multimedia can be given to users on an "Anytime, Anywhere" basis, and at higher data rates than previous generations. As the second generation was a total replacement of the first generation networks and handsets; and the third generation was a total replacement of second generation networks and handsets; so too the fourth generation cannot be an incremental evolution of current 3G technologies, but rather the total replacement of the current 3G networks and handsets. The international telecommunications regulatory and standardization bodies are working for commercial deployment of 4G networks roughly in the 2012-2015 time scale. There is no formal definition for what 4G is; however, there are certain objectives that are projected for 4G. These objectives include, that 4G will be a fully IP-based integrated system. 4G will be capable of providing between 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors, with premium quality and high security.
1.INTRODUCTION:The approaching 4G (fourth generation) mobile communication systems are projected to solve still-remaining problems of 3G (third generation) systems and to provide a wide varietyof new services, from high-quality voice to high-definition video to high-data-rate wireless channels.The term 4G is used broadly to include several types of broadband wireless access communication systems, not only cellular telephone systems. One of the terms used to describe 4G is MAGIC—Mobile multimedia, anytime anywhere, Global mobility support,integrated wireless solution, and customized personal service. The 4G systems not only will support the next generation of mobile service, but also will support the fixed wireless networks.
This paper presents an overall vision of the 4G features,framework, and integration of mobile communication. The features of 4G systems might be summarized with one word-Integration.The 4G systems are about seamlessly integrating terminals, networks, and applications to satisfy increasing user demands.
2.VISION OF 4G:This new generation of wireless is intended to complement and replace the 3G systems,perhaps in 5 to 10 years. Accessing information anywhere, anytime, with a seamless connection to a wide range of information and services, and receiving a large volume of information, data, pictures, video, and so on, are the keys of the 4G infrastructures.The future 4G infrastructures will consist of a set of various networks using IP (Internet protocol) as a common protocol so that users are in control because they will be able to choose every application and environment.
Based on the developing trends of mobile communication, 4G will have broader bandwidth, higher data rate, and smoother and quicker handoff and will focus on ensuring seamless service across a multitude of wireless systems and networks. The key concept is integrating the 4G capabilities with all of the existing mobile technologies through advanced technologies. Application adaptability and being highly dynamic are the main features of 4G services of interest to users. These features mean services can be delivered and be available to the personal preference of different users and support the users' traffic, air interfaces, radio environment, and quality of service. Connection with the network applications can be transferred into various forms and levels correctly and efficiently. The dominant methods of access to this pool of information will be the mobile telephone, PDA, and laptop to seamlessly access the voice communication, high-speed information services ,and entertainment broadcast services.
The fourth generation will encompass all systems from various networks, public to private; operator-driven broadband networks to personal areas; and ad hoc networks. 4G systems will be fully IP-based wireless Internet. This allencompassing integrated perspective shows the broad range of systems that the fourth generation intends to integrate, from satellite broadband to high altitude platform to cellular 3G and 3G systems to WLL (wireless local loop) and FWA (fixed wireless access) to WLAN. (wireless local area network) and PAN (personal area network),all with IP as the integrating mechanism. With 4G, a range of new services and models will be available.
3.KEY 4G TECHNOLOGIES:Some of the key technologies required for 4G are briefly described below:
3.1 OFDMA:Orthogonal Frequency Division Multiplexing (OFDM) not only provides clear advantages for physical layer performance, but also a framework for improving layer 2 performance by proposing an additional degree of free- dom. Using ODFM, it is possible to exploit the time domain, the space domain, the frequency domain to optimize radio channel usage. It ensures very robust transmission in multi-path environments with reduced receiver complexity. This not only provides additional flexibility for resource allocation (increasing the capacity), but also enables cross-layer optimization of radio link usage.
3.2 SOFTWARE DEFINED RADIO:Software Defined Radio (SDR) benefits from today’s high processing power to develop multi-band, multi-standard base stations and terminals. Although in future the terminals will adapt the air interface to the available radio access technology, at present this is done by the infrastructure.SDR makes this reconfiguration easy. In the context of 4G systems, SDR will become an enabler for the aggregation of multi-standard pico/micro cells.
3.3 MULTIPLE-INPUT MULTIPLE –OUTPUT:MIMO uses signal multiplexing between multiple transmitting antennas (space multiplex)and time or frequency. It is well suited to OFDM. In principle, MIMO is more efficient when many multiple path signals are received. The performance in cellular deployments is still subject to research and simulations. Handover technologies based on mobileIP technology have been considered for data and voice. Mobile IP techniques are slow but can be accelerated with classical methods (hierarchical, fast mobile IP). These methods are applicable to data and probably also voice. In single-frequency networks,it is necessary to reconsider the handover methods. Several techniques can be used when thecarrier to interference ratio is negative (e.g. VSFOFDM,bit repetition), but the drawback of these techniques is capacity.
4.QUALITY OF SERVICE:
• Traffic generated by the different services will not only increase traffic loads on the networks, but will also require different quality of service (QoS) requirements (e.g.,cell loss rate, delay, and jitter) for different streams (e.g., video, voice, data).
• Providing QoS guarantees in G networks is a non-trivial issue where both QoS
signaling across different networks and service differentiation between mobile flows will have to be addressed.
• One of the most difficult problems that are to be solved, when it comes to IP mobility,is how to insure the constant QoS level during the handover.
• Depending on whether the new access router is in the same or some subnetwork, we recognize the horizontal and vertical handover.
• However, the mobile terminal can not receive IP packets while the handover is finished. This time is called the handover latency.
• Handover latency has a great influence on the flow of multimedia applications in realtime.
• Mobile IPv6 have been proposed to reduce the handover latency and the number of lost packets.
• The field “Traffic Class” and “Flow Label” in IPv6 eader enables the routers to
secure the special QoS for specific packet series with marked priority.
5.SECURITY:
The heterogeneity of wireless networks complicates the security issue.
Dynamic reconfigurable, adaptive, and lightweight security mechanisms should be developed.
Security in wireless networks mainly involves authentication, confidentiality,integrity, and authorization for the access of network connectivity and QoS resources for the mobile nodes flow.
• AAA (Authentication Authorization Auditing) protocols provide a framework for such suffered especially for control plane functions and installing security policies in the mobile node such as encryption, decryption and filtering.
6.BENEFITS:
6.1 CONVERGENCE OF CELLULAR MOBILE NETWORKS AND
WLANS
6.1.1 Benefits for Operators:
• Higher bandwidths.
• Lower cost of networks and equipment.
• The use of licence-exempt spectrum.
• Higher capacity and QoS enhancement.
• Higher revenue.
6.1.2 Benefits for Users:
• Access to broadband multimedia services with lower cost and where mostly needed.
• Inter-network roaming.
6.2 CONVERGENCE OF MOBILE COMMUNICATIONS
AND BROADCASTING:
6.2.1 From broadcaster point of view:Introducing interactivity to their unidirectional point-to multipoint Broadcasting systems.That is, a broadband downlink based on DAB/DVB-T and a narrowband uplink based on 3G cellular systems.
6.2.2 From the cellular mobile operator point of view
roviding a complementary broadband downlink in vehicular environments to support IPbased multi-media traffic which is inherently asymmetrical.
7.APPLICATIONS:
7.1 VIRTUAL PRESENCE: This means that 4G provides user services at all times,even if the user is off-site.
7.2 VIRTUAL NAVIGATION: 4G provides users with virtual navigation through which a user can access a database of the streets, buildings etc.
7.3 TELE-GEOPROCESSING APPLICATIONS: This is a combination of GIS(Geographical Information System) and GPS (Global Positioning System) in which a user can get the location by querying.
7.4 TELE-MEDICINE AND EDUCATION: 4G will support remote health monitoring of patients. For people who are interested in life long education, 4G providesa good opportunity.
7.5 CRISIS MANAGEMENT: Natural disasters can cause break down in communication systems. In today’s world it might take days or 7 weeks to restore the system.But in 4G it is expected to restore such crisis issues in a few hours.
7.6 MULTIMEDIA – VIDEO SERVICES
_ 4G wireless systems are expected to deliver efficient multimedia services at very high data rates.
_ Basically there are two types of video services: bursting and streaming video services.
_ Streaming is performed when a user requires real-time video services, in which the server delivers data continuously at a playback rate.
_ Bursting is basically file downloading using a buffer and this is done at the highest data rate taking advantage of the whole available bandwidth.
8.CONCLUSION:As the history of mobile communications shows,attempts have been made to reduce a number of technologies to a single global standard. Projected 4G systems offer this promise of a standard that can be embraced worldwide through its key concept of integration. Future wireless networks will need to support diverse IP multimedia applications to allow sharing of resources among multiple users. There must be a low complexity of implementation and an efficient means of negotiation between the end users and the wireless infrastructure.The fourth generation promises to fulfill the goal of PCC (personal computing and communication—a vision that affordably provides high data rates everywhere over awireless network.4G is expected to be launched by 2010 and the world is looking forwardfor the most intelligent technology that would connect the entire globe.
ABSTRACT: 4G (also known as Beyond 3G), an abbreviation for Fourth-Generation, is a term used to describe the next complete evolution in wirelesscommunications. A 4G system will be able to provide a comprehensive IP solution where voice, data and streamed multimedia can be given to users on an "Anytime, Anywhere" basis, and at higher data rates than previous generations. As the second generation was a total replacement of the first generation networks and handsets; and the third generation was a total replacement of second generation networks and handsets; so too the fourth generation cannot be an incremental evolution of current 3G technologies, but rather the total replacement of the current 3G networks and handsets. The international telecommunications regulatory and standardization bodies are working for commercial deployment of 4G networks roughly in the 2012-2015 time scale. There is no formal definition for what 4G is; however, there are certain objectives that are projected for 4G. These objectives include, that 4G will be a fully IP-based integrated system. 4G will be capable of providing between 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors, with premium quality and high security.
1.INTRODUCTION:The approaching 4G (fourth generation) mobile communication systems are projected to solve still-remaining problems of 3G (third generation) systems and to provide a wide varietyof new services, from high-quality voice to high-definition video to high-data-rate wireless channels.The term 4G is used broadly to include several types of broadband wireless access communication systems, not only cellular telephone systems. One of the terms used to describe 4G is MAGIC—Mobile multimedia, anytime anywhere, Global mobility support,integrated wireless solution, and customized personal service. The 4G systems not only will support the next generation of mobile service, but also will support the fixed wireless networks.
This paper presents an overall vision of the 4G features,framework, and integration of mobile communication. The features of 4G systems might be summarized with one word-Integration.The 4G systems are about seamlessly integrating terminals, networks, and applications to satisfy increasing user demands.
2.VISION OF 4G:This new generation of wireless is intended to complement and replace the 3G systems,perhaps in 5 to 10 years. Accessing information anywhere, anytime, with a seamless connection to a wide range of information and services, and receiving a large volume of information, data, pictures, video, and so on, are the keys of the 4G infrastructures.The future 4G infrastructures will consist of a set of various networks using IP (Internet protocol) as a common protocol so that users are in control because they will be able to choose every application and environment.
Based on the developing trends of mobile communication, 4G will have broader bandwidth, higher data rate, and smoother and quicker handoff and will focus on ensuring seamless service across a multitude of wireless systems and networks. The key concept is integrating the 4G capabilities with all of the existing mobile technologies through advanced technologies. Application adaptability and being highly dynamic are the main features of 4G services of interest to users. These features mean services can be delivered and be available to the personal preference of different users and support the users' traffic, air interfaces, radio environment, and quality of service. Connection with the network applications can be transferred into various forms and levels correctly and efficiently. The dominant methods of access to this pool of information will be the mobile telephone, PDA, and laptop to seamlessly access the voice communication, high-speed information services ,and entertainment broadcast services.
The fourth generation will encompass all systems from various networks, public to private; operator-driven broadband networks to personal areas; and ad hoc networks. 4G systems will be fully IP-based wireless Internet. This allencompassing integrated perspective shows the broad range of systems that the fourth generation intends to integrate, from satellite broadband to high altitude platform to cellular 3G and 3G systems to WLL (wireless local loop) and FWA (fixed wireless access) to WLAN. (wireless local area network) and PAN (personal area network),all with IP as the integrating mechanism. With 4G, a range of new services and models will be available.
3.KEY 4G TECHNOLOGIES:Some of the key technologies required for 4G are briefly described below:
3.1 OFDMA:Orthogonal Frequency Division Multiplexing (OFDM) not only provides clear advantages for physical layer performance, but also a framework for improving layer 2 performance by proposing an additional degree of free- dom. Using ODFM, it is possible to exploit the time domain, the space domain, the frequency domain to optimize radio channel usage. It ensures very robust transmission in multi-path environments with reduced receiver complexity. This not only provides additional flexibility for resource allocation (increasing the capacity), but also enables cross-layer optimization of radio link usage.
3.2 SOFTWARE DEFINED RADIO:Software Defined Radio (SDR) benefits from today’s high processing power to develop multi-band, multi-standard base stations and terminals. Although in future the terminals will adapt the air interface to the available radio access technology, at present this is done by the infrastructure.SDR makes this reconfiguration easy. In the context of 4G systems, SDR will become an enabler for the aggregation of multi-standard pico/micro cells.
3.3 MULTIPLE-INPUT MULTIPLE –OUTPUT:MIMO uses signal multiplexing between multiple transmitting antennas (space multiplex)and time or frequency. It is well suited to OFDM. In principle, MIMO is more efficient when many multiple path signals are received. The performance in cellular deployments is still subject to research and simulations. Handover technologies based on mobileIP technology have been considered for data and voice. Mobile IP techniques are slow but can be accelerated with classical methods (hierarchical, fast mobile IP). These methods are applicable to data and probably also voice. In single-frequency networks,it is necessary to reconsider the handover methods. Several techniques can be used when thecarrier to interference ratio is negative (e.g. VSFOFDM,bit repetition), but the drawback of these techniques is capacity.
4.QUALITY OF SERVICE:
• Traffic generated by the different services will not only increase traffic loads on the networks, but will also require different quality of service (QoS) requirements (e.g.,cell loss rate, delay, and jitter) for different streams (e.g., video, voice, data).
• Providing QoS guarantees in G networks is a non-trivial issue where both QoS
signaling across different networks and service differentiation between mobile flows will have to be addressed.
• One of the most difficult problems that are to be solved, when it comes to IP mobility,is how to insure the constant QoS level during the handover.
• Depending on whether the new access router is in the same or some subnetwork, we recognize the horizontal and vertical handover.
• However, the mobile terminal can not receive IP packets while the handover is finished. This time is called the handover latency.
• Handover latency has a great influence on the flow of multimedia applications in realtime.
• Mobile IPv6 have been proposed to reduce the handover latency and the number of lost packets.
• The field “Traffic Class” and “Flow Label” in IPv6 eader enables the routers to
secure the special QoS for specific packet series with marked priority.
5.SECURITY:
The heterogeneity of wireless networks complicates the security issue.
Dynamic reconfigurable, adaptive, and lightweight security mechanisms should be developed.
Security in wireless networks mainly involves authentication, confidentiality,integrity, and authorization for the access of network connectivity and QoS resources for the mobile nodes flow.
• AAA (Authentication Authorization Auditing) protocols provide a framework for such suffered especially for control plane functions and installing security policies in the mobile node such as encryption, decryption and filtering.
6.BENEFITS:
6.1 CONVERGENCE OF CELLULAR MOBILE NETWORKS AND
WLANS
6.1.1 Benefits for Operators:
• Higher bandwidths.
• Lower cost of networks and equipment.
• The use of licence-exempt spectrum.
• Higher capacity and QoS enhancement.
• Higher revenue.
6.1.2 Benefits for Users:
• Access to broadband multimedia services with lower cost and where mostly needed.
• Inter-network roaming.
6.2 CONVERGENCE OF MOBILE COMMUNICATIONS
AND BROADCASTING:
6.2.1 From broadcaster point of view:Introducing interactivity to their unidirectional point-to multipoint Broadcasting systems.That is, a broadband downlink based on DAB/DVB-T and a narrowband uplink based on 3G cellular systems.
6.2.2 From the cellular mobile operator point of view
roviding a complementary broadband downlink in vehicular environments to support IPbased multi-media traffic which is inherently asymmetrical.7.APPLICATIONS:
7.1 VIRTUAL PRESENCE: This means that 4G provides user services at all times,even if the user is off-site.
7.2 VIRTUAL NAVIGATION: 4G provides users with virtual navigation through which a user can access a database of the streets, buildings etc.
7.3 TELE-GEOPROCESSING APPLICATIONS: This is a combination of GIS(Geographical Information System) and GPS (Global Positioning System) in which a user can get the location by querying.
7.4 TELE-MEDICINE AND EDUCATION: 4G will support remote health monitoring of patients. For people who are interested in life long education, 4G providesa good opportunity.
7.5 CRISIS MANAGEMENT: Natural disasters can cause break down in communication systems. In today’s world it might take days or 7 weeks to restore the system.But in 4G it is expected to restore such crisis issues in a few hours.
7.6 MULTIMEDIA – VIDEO SERVICES
_ 4G wireless systems are expected to deliver efficient multimedia services at very high data rates.
_ Basically there are two types of video services: bursting and streaming video services.
_ Streaming is performed when a user requires real-time video services, in which the server delivers data continuously at a playback rate.
_ Bursting is basically file downloading using a buffer and this is done at the highest data rate taking advantage of the whole available bandwidth.
8.CONCLUSION:As the history of mobile communications shows,attempts have been made to reduce a number of technologies to a single global standard. Projected 4G systems offer this promise of a standard that can be embraced worldwide through its key concept of integration. Future wireless networks will need to support diverse IP multimedia applications to allow sharing of resources among multiple users. There must be a low complexity of implementation and an efficient means of negotiation between the end users and the wireless infrastructure.The fourth generation promises to fulfill the goal of PCC (personal computing and communication—a vision that affordably provides high data rates everywhere over awireless network.4G is expected to be launched by 2010 and the world is looking forwardfor the most intelligent technology that would connect the entire globe.