(Size: 1.66 MB / Downloads: 455)
The present cell phones have it all. Today phones have everything ranging from the smallest size, largest phone memory, speed dialing, video player, audio player, and camera and so on. Recently with the development of Pico nets and Blue tooth technology data sharing has become a child's play. Earlier with the infrared feature you can share data within a line of sight that means the two devices has to be aligned properly to transfer data, but in case of blue tooth you can transfer data even when you have the cell phone in your pocket up to a range of 50 meters. The creation and entry of 5G technology into the mobile marketplace will launch a new revolution in the way international cellular plans are offered.
The global mobile phone is upon the cell phone market. Just around the corner, the newest 5G technologies will hit the mobile market with phones used in China being able to access and call locally phones in Germany. Truly innovative technology changing the way mobile phones will be used. With the emergence of cell phones, which are similar to a PDA, you can now have your whole office within the phone. Cell phones will give tough competitions to laptop manufacturers and normal computer designers. Even today there are phones with gigabytes of memory storage and the latest operating systems. Thus one can say that with the current trends, the industry has a real bright future if it can handle the best technologies and can produce affordable handsets for its customers. Thus you will get all your desires unleashed in the near future when these smart phones take over the market. 5G Network's router and switch technology delivers Last Yard Connectivity between the Internet access provider and building occupants. 5G's technology intelligently distributes Internet access to individual nodes within the building.
1.1 2G-5G Networks
The first generation of mobile phones was analog systems that emerged in the early 1980s. The second generation of digital mobile phones appeared in 1990s along with the first digital mobile networks. During the second generation, the mobile telecommunications industry experienced exponential growth in terms of both subscribers and value-added services. Second generation networks allow limited data support in the range of 9.6 kbps to 19.2 kbps. Traditional phone networks are used mainly for voice transmission, and are essentially circuit-switched networks.
2.5G networks, such as General Packet Radio Service (GPRS), are an extension of 2G networks, in that they use circuit switching for voice and packet switching for data transmission resulting in its popularity since packet switching utilizes bandwidth much more efficiently. In this system, each user’s packets compete for available bandwidth, and users are billed only for the amount of data transmitted. 3G networks were proposed to eliminate many problems faced by 2G and 2.5G networks, especially the low speeds and incompatible technologies such as Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA) in different countries. Expectations for 3G included increased bandwidth; 128 Kbps for mobile stations, and 2 Mbps for fixed applications. In theory, 3G should work over North American as well as European and Asian wireless air interfaces. In reality, the outlook for 3G is not very certain. Part of the problem is that network providers in Europe and North America currently maintain separate standards’ bodies (3GPP for Europe and Asia; 3GPP2 for North America). The standards’ bodies have not resolved the differences in air interface technologies.
There is also a concern that in many countries 3G will never be deployed due to its cost and poor performance. Although it is possible that some of the weaknesses at physical layer will still exist in 4G systems, an integration of services at the upper layer is expected. The evolution of mobile networks is strongly influenced by business challenges and the direction mobile system industry takes. It also relates to the radio access spectrum and the control restrictions over it that varies from country to country. However, as major technical advances are being standardized it becomes more complex for industry alone to choose a suitable evolutionary path. Many mobile system standards for Wide Area Networks (WANs) already exists including the popular ones such as Universal Mobile Telecommunications Systems (UMTS), CDMA, and CDMA-2000 (1X/3X). In addition there are evolving standards for Personal Area Networks (PANs), such as Bluetooth wireless, and for WLANs, such as IEEE 802.11. The current trend in mobile systems is to support the high bit rate data services at the downlink via High Speed Downlink Packet Access (HSDPA). It provides a smooth evolutionary path for UMTS networks to higher data rates in the same way as Enhanced Data rates for Global Evolution (EDGE) do in Global Systems for Mobile communication (GSM). HSPDA uses shared channels that allow different users to access the channel resources in packet domain. It provides an efficient means to share spectrum that provides support for high data rate packet transport on the downlink, which is well adapted to urban environment and indoor applications. Initially, the peak data rates of 10 Mbps may be achieved using HSPDA. The next target is to reach 30 Mbps with the help of antenna array processing technologies followed by the enhancements in air interface design to allow even higher data rates.
Another recent development is a new framework for mobile networks that is expected to provide multimedia support for IP telecommunication services, called as IP Multimedia Subsystems (IMS). Real-time rich multimedia communication mixing telecommunication and data services could happen due to IMS in wireline broadband networks. However, mobile carriers cannot offer their customers the freedom to mix multimedia components (text, pictures, audio, voice, video) within one call. Today a two party voice call cannot be extended to a multi-party audio and video conference. IMS overcomes such limitations and makes these scenarios possible. The future of mobile systems is largely dependent upon the development and evolution of 4G systems, multimedia networking, and upto some extent, photonic networks. It is expected that initially the 4G mobile systems will be used independent from other technologies. With gradual growth of high speed data support to multimegabits per second, an integrations of services will happen. In addition, developments in photonic switching might allow mobile communication on a completely photonic network using Wavelength Division Multiplexing (WDM) on photonic switches and routers. The evolutionary view of 4G systems to 5G include a support of wireless world wide web allowing a highly flexible and reconfigurable dynamic adhoc networks.
The basic architecture of wireless mobile system consists of a mobile phone connected to the wired world via a single hop wireless connection to a Base Station (BS), which is responsible for carrying the calls within its region called cell (Figure 2.1). Due to limited coverage provided by a BS, the mobile hosts change their connecting base stations as they move from one cell to another
A hand-off occurs when a mobile system changes its BS. The mobile station communicates via the BS using one of the wireless frequency sharing technologies such as FDMA, TDMA, CDMA etc. Each BS is connected to a Mobile Switching Centre (MSC) through fixed links, and each MSC is connected to others via Public Switched Telephone Network (PSTN). The MSC is a local switching exchange that handles switching of mobile user from one BS to another. It also locates the current cell location of a mobile user via a Home Location Register (HLR) that stores current location of each mobile that belongs to the MSC. In addition, the MSC contains a Visitor Locations Register (VLR) with information of visiting mobiles from other cells. The MSC is responsible for determining the current location of a target mobile using HLR, VLR and by communicating with other MSCs. The source MSC initiates a call setup message to MSC covering ta
The first generation cellular implementation consisted of analog systems in 450-900 MHz frequency range using frequency shift keying for signalling and Frequency Division Multiple Access (FDMA) for spectrum sharing. The second generation implementations consist of TDMA/CDMA implementations with 900, 1800 MHz frequencies. These systems are called GSM for Europe and IS-136 for US. The respective 2.5G implementations are called GPRS and CDPD followed by 3G implementations.
Third generation mobile systems are intended to provide a global mobility with wide range of services including voice calls, paging, messaging, Internet and broadband data. IMT-2000 defines the standard applicable for North America. In Europe, the equivalent UMTS standardization is in progress. In 1998, a Third Generation Partnership Project (3GPP) was formed to unify and continue the technical specification work. Later, the Third Generation Partnership Project 2 (3GPP2) was formed for technical development of CDMA-2000 technology.
3G mobile offers access to broadband multimedia services, which is expected to become all IP based in future 4G systems. However, current 3G networks are not based on IP; rather they are an evolution from existing 2G networks. Work is going on to provide 3G support and Quality of Service (QoS) in IP and mobility protocols. The situation gets more complex when we consider the WLAN research and when we expect it to become mobile. It is expected that WLANs will be installed in trains, trucks, and buildings. In addition, it may just be formed on an ad-hoc basis (like ad-hoc networks) between random collections of devices that happen to come within radio range of one another (Figure 2.2).
In general, 4G architecture includes three basic areas of connectivity; PANs (such as Bluetooth), WANs (such as IEEE 802.11), and cellular connectivity. Under this umbrella, 4G will provide a wide range of mobile devices that support global roaming. Each device will be able to interact with Internet-based information that will be modified on the fly for the network being used by the device at that moment (Figure 2.3). In 5G mobile IP, each cell phone is expected to have a permanent "home" IP address, along with a "careof" address that represents its actual location. When a computer somewhere on the Internet needs to communicate with the cell phone, it first sends a packet to the phone's home address.