19-03-2014, 02:18 PM
Emerging trends in wireless communication
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Abstract
In this rapidly increasing world of technology, there is an enormous growth in the field of wireless technologies. The demand for wireless communication systems of increasing sophistication and ubiquity has led to the need for a better understanding of fundamental issues in communication theory and electromagnetic systems and their implications for the design of highly-capable wireless systems. A great deal of research is taking place in various aspects of mobile and wireless communications. This paper is an attempt to present a few of these technologies which have a great industrial impact as it is not possible to cover all the emerging trends. The paper presents the main characteristics and design issues and provides a description of wireless communication networks like Powerline Communication (PLC), Ultra Wideband(UWB), Free Space Optics (FSO), Mobile Ad Hoc Networks (MANETs), wireless sensor networks (WSNs), and Flash OFDM (Orthogonal Frequency Division Multiplexing).
Keywords - PLC, UWB, FSO, MANETs, WSNs, OFDM;
INTRODUCTION
There is a substantial uncertainty about the future generation of various wireless networks and the evolution of mobile networks. There are many remarkable changes taking place in wireless networks. It is obvious that Wireless Networks is witnessed as an unavoidable threat for other and older kind of networking technologies. Wireless networks provide an inexpensive and easy way to share a single Internet connection among several computers. With the help of wireless networks telecommunication networks and enterprise business installations avoid the costly process of introducing cables into a
building, or as a connection between various equipment locations. Wireless communication networks are generally implemented and administered using a transmission system. This implementation takes place at the physical level (layer) of the OSI model network structure. Wireless networks are defined on the bases of their size (that is the number of machines), their range and the speed of data transfer. There are several types of networks available such as Wireless PAN, LAN, MAN, WAN, Mobile Devices Networks and Global Systems for Mobile Communications.
The development of wireless networks is still in progress as the usage is rapidly growing. Personal
FREE SPACE OPTICS
Free-space optical communication (FSO) is an optical communication technology that uses light propagating in free space to transmit data for telecommunications or computer networking. "Free pace" means air, outer space, vacuum, or something
similar. This contrasts with using solids such as optical fiber cable or an optical transmission line. The technology is useful where the physical connections are impractical due to high costs or other considerations.
The theory of FSO is essentially the same as that for fiber optic transmission. The difference is that the energy beam is collimated and sent through clear air or space from the source to the destination, rather than guided through an optical fiber. If the energy source does not produce a sufficiently parallel beam to travel the required distance, collimation can be done with lenses. At the source, the visible or IR energy is modulated with the data to be transmitted. At the destination, the beam is intercepted by a photo-detector, the data is extracted from the visible or IR beam (demodulated), and the resulting signal is amplified and sent to the hardware.
WIRELESS SENSOR NETWORKS
A wireless sensor network (WSN) consists of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, humidity, motion or pollutants and to cooperatively pass their data through the network to a main location. The WSN is built of "nodes" – from a few to several hundreds or even thousands, where each node is connected to one (or sometimes several) sensors. Each such sensor network node has typically several parts: a radio transceiver with an internal antenna or connection to an external antenna, a micro controller, an electronic circuit for interfacing with the sensors and an energy source, usually a battery or an embedded form of energy harvesting. A sensor node might vary in size from that of a shoebox down to the size of a grain of dust, although functioning "motes" of genuine microscopic dimensions have yet to be created.
ADVANCES IN PHYSICAL LAYER
In the next generation wireless communication systems, major research challenges in facilitating broadband service with high spectral efficiency may lie in the physical layer. Hence, it has become crucial to incorporate the recent technical advances in the physical layer into the future wireless systems. Multiple-input multiple-output (MIMO) is a promising technology to improve the wireless system capacity and in the past few years, a lot of research has been carried out in various aspects of MIMO systems. Space-time (ST) coding has evolved as an effective transmit diversity technique to achieve high performance over fading wireless channels. Hence, ST coding based transmit diversity (STTD) has already been included in 3G wireless communication standards (e.g., WCDMA systems). Cooperative diversity has recently emerged as a very popular technique to achieve an additional diversity gain to combat the effects of severe channel fading.
CONCLUDING REMARKS
Persistent technological evolution in wireless communications is needed mainly due to emerging demands for broadband packet-based services. In this paper, we briefly discussed the evolution towards the future generation broadband wireless communications systems aiming to provide truly ubiquitous broadband wireless access. We have also presented an overview of recent advances and state-of-the-art research in various aspects of wireless communication. We have mainly focused on the advances in the physical layer, wireless personal area networks (WPANs), cross-layer design, quality of service (QoS) provisioning and wireless security. Future research challenges in each area have also been mentioned.
[attachment=60247]
Abstract
In this rapidly increasing world of technology, there is an enormous growth in the field of wireless technologies. The demand for wireless communication systems of increasing sophistication and ubiquity has led to the need for a better understanding of fundamental issues in communication theory and electromagnetic systems and their implications for the design of highly-capable wireless systems. A great deal of research is taking place in various aspects of mobile and wireless communications. This paper is an attempt to present a few of these technologies which have a great industrial impact as it is not possible to cover all the emerging trends. The paper presents the main characteristics and design issues and provides a description of wireless communication networks like Powerline Communication (PLC), Ultra Wideband(UWB), Free Space Optics (FSO), Mobile Ad Hoc Networks (MANETs), wireless sensor networks (WSNs), and Flash OFDM (Orthogonal Frequency Division Multiplexing).
Keywords - PLC, UWB, FSO, MANETs, WSNs, OFDM;
INTRODUCTION
There is a substantial uncertainty about the future generation of various wireless networks and the evolution of mobile networks. There are many remarkable changes taking place in wireless networks. It is obvious that Wireless Networks is witnessed as an unavoidable threat for other and older kind of networking technologies. Wireless networks provide an inexpensive and easy way to share a single Internet connection among several computers. With the help of wireless networks telecommunication networks and enterprise business installations avoid the costly process of introducing cables into a
building, or as a connection between various equipment locations. Wireless communication networks are generally implemented and administered using a transmission system. This implementation takes place at the physical level (layer) of the OSI model network structure. Wireless networks are defined on the bases of their size (that is the number of machines), their range and the speed of data transfer. There are several types of networks available such as Wireless PAN, LAN, MAN, WAN, Mobile Devices Networks and Global Systems for Mobile Communications.
The development of wireless networks is still in progress as the usage is rapidly growing. Personal
FREE SPACE OPTICS
Free-space optical communication (FSO) is an optical communication technology that uses light propagating in free space to transmit data for telecommunications or computer networking. "Free pace" means air, outer space, vacuum, or something
similar. This contrasts with using solids such as optical fiber cable or an optical transmission line. The technology is useful where the physical connections are impractical due to high costs or other considerations.
The theory of FSO is essentially the same as that for fiber optic transmission. The difference is that the energy beam is collimated and sent through clear air or space from the source to the destination, rather than guided through an optical fiber. If the energy source does not produce a sufficiently parallel beam to travel the required distance, collimation can be done with lenses. At the source, the visible or IR energy is modulated with the data to be transmitted. At the destination, the beam is intercepted by a photo-detector, the data is extracted from the visible or IR beam (demodulated), and the resulting signal is amplified and sent to the hardware.
WIRELESS SENSOR NETWORKS
A wireless sensor network (WSN) consists of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, humidity, motion or pollutants and to cooperatively pass their data through the network to a main location. The WSN is built of "nodes" – from a few to several hundreds or even thousands, where each node is connected to one (or sometimes several) sensors. Each such sensor network node has typically several parts: a radio transceiver with an internal antenna or connection to an external antenna, a micro controller, an electronic circuit for interfacing with the sensors and an energy source, usually a battery or an embedded form of energy harvesting. A sensor node might vary in size from that of a shoebox down to the size of a grain of dust, although functioning "motes" of genuine microscopic dimensions have yet to be created.
ADVANCES IN PHYSICAL LAYER
In the next generation wireless communication systems, major research challenges in facilitating broadband service with high spectral efficiency may lie in the physical layer. Hence, it has become crucial to incorporate the recent technical advances in the physical layer into the future wireless systems. Multiple-input multiple-output (MIMO) is a promising technology to improve the wireless system capacity and in the past few years, a lot of research has been carried out in various aspects of MIMO systems. Space-time (ST) coding has evolved as an effective transmit diversity technique to achieve high performance over fading wireless channels. Hence, ST coding based transmit diversity (STTD) has already been included in 3G wireless communication standards (e.g., WCDMA systems). Cooperative diversity has recently emerged as a very popular technique to achieve an additional diversity gain to combat the effects of severe channel fading.
CONCLUDING REMARKS
Persistent technological evolution in wireless communications is needed mainly due to emerging demands for broadband packet-based services. In this paper, we briefly discussed the evolution towards the future generation broadband wireless communications systems aiming to provide truly ubiquitous broadband wireless access. We have also presented an overview of recent advances and state-of-the-art research in various aspects of wireless communication. We have mainly focused on the advances in the physical layer, wireless personal area networks (WPANs), cross-layer design, quality of service (QoS) provisioning and wireless security. Future research challenges in each area have also been mentioned.