The rapid growth in mobile communications has led to an increasing demand for wide- band high data rate communications services. In recent years, Distributed Antenna Systems (DAS) has emerged as a promising candidate for future (beyond 3G or 4G) mobile communications, as illustrated by projects such as FRAMES and FuTURE. The architecture of DAS inherits and develops the concepts of pico- or micro-cell systems, where multiple distributed antennas or access points (AP) are connected to and con- trolled by a central unit.
标签： Distributed Antenna Systems
上传时间： 2020-05-27
上传用户：shancjb
The next-generation wireless broadband technology is changing the way we work, live, learn, and communicate through effective use of state- of-the-art mobile broadband technology. The packet-data-based revolu- tion started around 2000 with the introduction of 1x Evolved Data Only (1xEV-DO) and 1x Evolved Data Voice (1xEV-DV) in 3GPP2 and High Speed Downlink Packet Access (HSDPA) in 3GPP. The wireless broad- band fourth-generation technology (4G) is an evolution of the packet- based 3G system and provides a comprehensive evolution of the Universal Mobile Telecommunications System specifications so as to remain competitive with other broadband systems such as 802.16e (WiMAX)
标签： Essentials LTE-A LTE and 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
With the rapid growth of the wireless mobile applications, wireless voice has begun to challenge wireline voice, whereas the desire to access e-mail, surf the Web or download music (e.g., MP3) wirelessly is increasing for wireless data. While second generation (2G) cellular wireless systems, such as cdmaOne1, GSM2 and TDMA3, introduced digital technology to wireless cellular systems to deal with the increasing demand for wireless applications, there is still the need for more spectrally efficient technologies for two reasons. First, wireless voice capacity is expected to continue to grow. Second, the introduction of high-speed wireless data will require more bandwidth.
标签： Wireless Systems Mobile Beyond and 3G
上传时间： 2020-05-30
上传用户：shancjb
At recent major international conferences on wireless communications, there have been several sessions on beyond third generation (3G) or fourth generation(4G)mobilecommunicationssystems,wheremodulation/demod- ulation and multiplexing/multiple access schemes related to multicarrier techniques have drawn a lot of attention. We often met at the conference venuesandrealizedthatnobookcoveredthebasicsofmulticarriertechniques to recent applications aiming at the 4G systems. Therefore, we decided to write a book on multicarrier techniques for 4G mobile communications systems.
标签： Communications Multicarrier Techniques Mobile for 4G
上传时间： 2020-05-31
上传用户：shancjb
It is more than a decade since GSM was first commercially available. After some unexpected delay, it seems that finally UMTS is here to stay as a 3G system standardised by 3GPP, at least for another ten years. UMTS will enable multi-service, multi-rate and flexible IP native-based mobile technologies to be used in wide area scenarios and also pave the way for a smooth transition from circuit switched voice networks to mobile packet services.
标签： Management Strategies Resource Radio
上传时间： 2020-06-01
上传用户：shancjb
Convergence between the two largest networks (Telecom and IP) is taking place very rapidly and at diff erent levels: (1) network level: unifi cation of IP networks with traditional Telecom networks through evolving standards (Session Initiation Protocol (SIP), Realtime Transfer Protocol (RTP), SS7, 3G) to support interopera- bility; (2) service level: traditional Telecom services like voice calls are being provi- sioned on the IP backbone (VoIP), while traditional IP services (most data-driven services such as multimedia, browsing, chatting, gaming, etc.) are accessible over the Telecom network.
标签： Platforms Delivery Service
上传时间： 2020-06-01
上传用户：shancjb
Software defined radio (SDR) is an exciting new field for the wireless indus- try; it is gaining momentum and beginning to be included in commercial and defense products. The technology offers the potential to revolutionize the way radios are designed, manufactured, deployed, and used. SDR prom- ises to increase flexibility, extend hardware lifetime, lower costs, and reduce time to market
标签： Software Defined Radio for 3G
上传时间： 2020-06-01
上传用户：shancjb
When 3GPP started standardizing the IMS a few years ago, most analysts expected the number of IMS deploymentsto grow dramatically as soon the initial IMS specifications were ready (3GPP Release 5 was functionallyfrozenin the first half of 2002and completedshortly after that). While those predictions have proven to be too aggressive owing to a number of upheavals hitting the ICT (Information and Communications Technologies) sector, we are now seeing more and more commercial IMS-based service offerings in the market. At the time of writing (May 2008), there are over 30 commercial IMS networks running live traffic, addingup to over10million IMS users aroundthe world; the IMS is beingdeployedglobally. In addition, there are plenty of ongoing market activities; it is estimated that over 130 IMS contracts have been awarded to all IMS manufacturers. The number of IMS users will grow substantially as these awarded contracts are launched commercially. At the same time, the number of IMS users in presently deployed networks is steadily increasing as new services are introduced and operators running these networks migrate their non-IMS users to their IMS networks.
标签： Multimedia Subsystem The IMS 3G IP
上传时间： 2020-06-01
上传用户：shancjb
