Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC channel and the maximum data rate that the system can operate since data transmission is completely season dependent.
标签: Communication Optical System Space Free
上传时间: 2020-05-27
上传用户:shancjb
The wireless market has experienced a phenomenal growth since the first second- Generation (2G) digital cellular networks, based on global system for mobile communications (GSM) technology, were introduced in the early 1990s. Since then, GSM has become the dominant global 2G radio access standard. Almost 80% of today’s new subscriptions take place in one of the more than 460 cellular networks that use GSM technology. This growth has taken place simultaneously with the large experienced expansion of access to the Internet and its related multimedia services.
标签: Performance Evolution GPRS EDGE GSM and
上传时间: 2020-05-27
上传用户:shancjb
This book describes how global mobile communication was made. It is written for those who want or need to know how this was achieved e.g.: † Young professionals who want to build their career on GSM and UMTS and need to understand the basics † Strategic and technical planners who want to drive the future GSM and UMTS develop- ment † Strategists who plan to repeat GSM’s success in the fourth Generation † Academics, who want to understand and analyse the development of GSM and UMTS; † Activists in other large scale international communication projects who want to use experiences gained
标签: Creation UMTS GSM and The of
上传时间: 2020-05-27
上传用户:shancjb
With the rapid growth in the number of wireless applications, services and devices, using a single wireless technology such as a second Generation (2G) and third gener- ation (3G) wireless system would not be efficient to deliver high speed data rate and quality-of-service (QoS) support to mobile users in a seamless way. The next genera- tion wireless systems (also sometimes referred to as Fourth Generation (4G) systems) are being devised with the vision of heterogeneity in which a mobile user/device will be able to connect to multiple wireless networks (e.g., WLAN, cellular, WMAN) simultaneously.
标签: Heterogeneous Wireless Networks Access
上传时间: 2020-05-27
上传用户:shancjb
The first Third Generation Partnership Project (3GPP) Wideband Code Division Multiple Access (WCDMA) networks were launched during 2002. By the end of 2005 there were 100 open WCDMA networks and a total of over 150 operators having frequency licenses for WCDMA operation. Currently, the WCDMA networks are deployedinUniversalMobileTelecommunicationsSystem(UMTS)bandaround2GHz in Europe and Asia including Japan and Korea. WCDMA in America is deployed in the existing 850 and 1900 spectrum allocations while the new 3G band at 1700/2100 is expected to be available in the near future. 3GPP has defined the WCDMA operation also for several additional bands, which are expected to be taken into use during the coming years.
标签: HSDPAHSUPA Access Speed Radio UMTS High for
上传时间: 2020-05-27
上传用户:shancjb
The third Generation (3G) mobile communication system is the next big thing in the world of mobile telecommunications. The first Generation included analog mobile phones [e.g., Total Access Communications Systems (TACS), Nordic Mobile Telephone (NMT), and Advanced Mobile Phone Service (AMPS)], and the second Generation (2G) included digital mobile phones [e.g., global system for mobile communications (GSM), personal digital cellular (PDC), and digital AMPS (D-AMPS)]. The 3G will bring digital multimedia handsets with high data transmission rates, capable of providing much more than basic voice calls.
标签: Communications Introduction Mobile 3G to
上传时间: 2020-05-27
上传用户:shancjb
To meet the future demand for huge traffic volume of wireless data service, the research on the fifth Generation (5G) mobile communication systems has been undertaken in recent years. It is expected that the spectral and energy efficiencies in 5G mobile communication systems should be ten-fold higher than the ones in the fourth Generation (4G) mobile communication systems. Therefore, it is important to further exploit the potential of spatial multiplexing of multiple antennas. In the last twenty years, multiple-input multiple-output (MIMO) antenna techniques have been considered as the key techniques to increase the capacity of wireless communication systems. When a large-scale antenna array (which is also called massive MIMO) is equipped in a base-station, or a large number of distributed antennas (which is also called large-scale distributed MIMO) are deployed, the spectral and energy efficiencies can be further improved by using spatial domain multiple access. This paper provides an overview of massive MIMO and large-scale distributed MIMO systems, including spectral efficiency analysis, channel state information (CSI) acquisition, wireless transmission technology, and resource allocation.
标签: Large-scale Antenna Systems
上传时间: 2020-05-27
上传用户:shancjb
In the nineteenth century, scientists, mathematician, engineers and innovators started investigating electromagnetism. The theory that underpins wireless communications was formed by Maxwell. Early demonstrations took place by Hertz, Tesla and others. Marconi demonstrated the first wireless transmission. Since then, the range of applications has expanded at an immense rate, together with the underpinning technology. The rate of development has been incredible and today the level of technical and commercial maturity is very high. This success would not have been possible without understanding radio- wave propagation. This knowledge enables us to design successful systems and networks, together with waveforms, antennal and transceiver architectures. The radio channel is the cornerstone to the operation of any wireless system.
标签: LTE-Advanced Generation Next and
上传时间: 2020-05-27
上传用户:shancjb
MIMO-OFDM is a key technology for next-Generation cellular communications (3GPP-LTE, Mobile WiMAX, IMT-Advanced) as well as wireless LAN (IEEE 802.11a, IEEE 802.11n), wireless PAN (MB-OFDM), and broadcasting (DAB, DVB, DMB). This book provides a comprehensive introduction to the basic theory and practice of wireless channel modeling, OFDM, and MIMO, with MATLAB ? programs to simulate the underlying techniques on MIMO-OFDMsystems.Thisbookisprimarilydesignedforengineersandresearcherswhoare interested in learning various MIMO-OFDM techniques and applying them to wireless communications.
标签: Communications MIMO-OFDM Wireless MATLAB with
上传时间: 2020-05-28
上传用户:shancjb
Mobile multimedia communication is increasingly in demand because of the basic need to communi- cate at any time, anywhere, using any technology. In addition, to voice communication, people have a desire to access a range of other services that comprise multimedia elements—text, image, animation, high fidelity audio and video using mobile communication networks. To meet these demands, mobile communication technologies has evolved from analog to digital, and the networks have passed through a number of Generations from first Generation (1G) to fourth Generation (4G).
标签: Communications Multimedia Concepts Mobile
上传时间: 2020-05-30
上传用户:shancjb