Fourth generation wireless system is a packet switched wireless system with wide area coverage and high throughput. It is designed to be cost effective and to provide high spectral efficiency. Mobile speed will be up to 200km/hr. The high performance is achieved by the use of long term channel prediction, in both time and frequency, scheduling among users and smart antennas combined with adaptive modulation and power control. Frequency band is 2-8 GHz. it gives the ability for worldwide roaming to access cell anywhere.
IMPLEMENTATION USING 4G
The goal of 4G is to replace the current proliferation of core mobile networks with a single worldwide core network standard, based on IP for control, video, packet data, and voice. This will provide uniform video, voice, and data services to the mobile host, based entirely on IP.
The objective is to offer seamless multimedia services to users accessing an all IP‐based infrastructure through heterogeneous access technologies. IP is assumed to act as an adhesive for providing global connectivity and mobility among networks.
An all IP‐based 4G wireless network has inherent advantages over its predecessors. It is compatible with, and independent of the underlying radio access technology. An IP wireless network replaces the old Signaling System 7 telecommunications protocol, which is considered massively redundant. This is because Signaling System 7 signal transmission consumes a larger part of network bandwidth even when there is no signaling traffic for the simple reason that it uses a call setup mechanism to reserve bandwidth, rather time/frequency slots in the radio waves. IP networks, on the other hand, are connectionless and use the slots only when they have data to send. Hence there is optimum usage of the available bandwidth.
Today, wireless communications are heavily biased toward voice, even though studies indicate that growth in wireless data traffic is rising exponentially relative to demand for voice traffic. Because an all IP core layer is easily scalable, it is ideally suited to meet this challenge. The goal is a merged data/voice/multimedia network.
4G technology is significant because users joining the network add mobile routers to the network infrastructure. Because users carry much of the network with them, network capacity and coverage is dynamically shifted to accommodate changing user patterns.
As people congregate and create pockets of high demand, they also create additional routes for each other, thus enabling additional access to network capacity. Users will automatically hop away from congested routes to less congested routes. This permits the network to dynamically and automatically self‐balance capacity, and increase network utilization.
What may not be obvious is that when user devices act as routers, these devices are actually part of the network infrastructure. So instead of carriers subsidizing the cost of user devices (e.g, handsets, PDAs, of laptop computers), consumers actually subsidize and help deploy the network for the carrier. With a cellular infrastructure, users contribute nothing to the network. They are just consumers competing for resources. But in wireless ad hoc peer — to — peer networks, users cooperate — rather than compete — for network resources. Thus, as the service gains popularity and the number of users increases, service likewise improves for all users.
With traditional wireless networks, about 80% of the cost is for site acquisition and installation, and just 20% is for the technology. Rising land and labor costs means installation costs tend to rise over time, subjecting the service providers business models to some challenging issues in the out years. With wireless peer‐to‐peer networking, however, about 80% of the cost is the technology and only 20% is the installation. Because technology costs tend to decline over time, a current viable business model should only become more profitable over time. The devices will get cheaper, and service providers will reach economies of scale sooner because they will be able to pass on the infrastructure savings to consumers, which will further increase the rate of penetration.
CHINESE COMPANIES IN RUSSIA
The International Telecommunication Union and the 4G Alliance defined 4G technology as next generation of wireless telecommunications, which will achieve data rates up to 1 Gbit/s in stationary applications and up to 100 Mbit/s in terms of data exchange with mobile access. Technology 4G will allow subscribers to watch high-definition multi-channel television, control home appliances using mobile devices and make cheap long distance phone calls.
The main participants of the 4G alliance are ZTE Corporation, and other Chinese companies. Both companies are cooperating with Russian partners like mobile operator MTS, which has launched a commercial service 4G network based on LTE (Long Term Evolution) in Uzbekistan. The network is deployed in the central part of Tashkent in the frequency range 2.5-2.7 GHz. The supplier of equipment for the construction of the network is the Chinese Huawei Technologies. In 2010, Huawei recorded revenues of US$28 billion. Its products and services have been deployed in more than 140 countries and it currently serves 45 of the world's 50 largest telecoms operators.
Central China Normal University. College of Computers.
Podvigalkin Dmitry (Ye Li).