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Spectrum

  • Distributed+Quality-of-Service+Support

    This thesis is about wireless communication in shared radio Spectrum. Its origin and motivation is ideally represented by the two quotations from above. In this thesis, the support of Quality-of-Service (QoS) in cognitive radio networks is analyzed. New approaches to distributed coordination of cognitive radios are developed in different Spectrum sharing scenarios. The Wireless Local Area Network (WLAN) 802.11 proto- col of the Institute of Electrical and Electronics Engineers (IEEE) (IEEE, 2003) with its enhancement for QoS support (IEEE, 2005d) is taken as basis. The Medium Access Control (MAC) of 801.11(e) is modified to realize flexible and dynamic Spectrum assignment within a liberalized regulation framework.

    标签: Quality-of-Service Distributed Support

    上传时间: 2020-05-27

    上传用户:shancjb

  • HSDPAHSUPA+for+UMTS+High+Speed+Radio+Access

    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

  • qorvo-carrier-aggregation-fundamentals

    Mobile operators must continuously pursue cost‐ effective and efficient solutions to meet the high data demand requirements of their subscribers. Limited Spectrum allocations and non‐contiguous Spectrum blocks continue to pose challenges for mobile operators supporting large data uploads and downloads across their networks. With the increase in video and social media content, the challenges have increased exponentially.

    标签: qorvo-carrier-aggregation-fundame ntals

    上传时间: 2020-05-31

    上传用户:shancjb

  • Radio Propagation Measurement

    Radio propagation measurements and channel modelling continue to be of fundamental importance to radio system design. As new technology enables dynamic Spectrum access and higher data rates, radio propagation effects such as shadowing, the presence of multipath and frequency dispersion are the limiting factors in the design of wireless communication systems. While there are several books covering the topic of radio propagation in various frequency bands, there appears to be no books on radio propagation measurements, which this book addresses at length. 

    标签: Propagation Measurement Radio

    上传时间: 2020-05-31

    上传用户:shancjb

  • Radio Wave Propagation

    One of the prerequisites for the development of telecommunication services is the understanding of the propagation of the waves, either acoustic, electromagnetic, radio or light waves, which are used for the transmission of information. In this work, we shall limit ourselves to the study of radio waves: this term apply to the electromagnetic waves used in radio communications. Their frequency Spectrum is very broad, and is divided into the following frequency bands : ELF waves (f < 3 kHz), VLF (3-30 kHz), LF waves (30-300 kHz), MF waves (300-3000 kHz), HF (3-30 MHz), VHF waves (30-300 MHz), UHF waves (300-3000 MHz), SHF waves (3-30 GHz), EHF waves (30-300 GHz) and sub- EHF waves (300-3000 GHz).

    标签: Propagation Radio Wave

    上传时间: 2020-05-31

    上传用户:shancjb

  • RFIC+Design+for+Cognitive+Radio+Systems

    Cognitive radios have become a vital solution that allows sharing of the scarce frequency Spectrum available for wireless systems. It has been demonstrated that it can be used for future wireless systems as well as integrated into 4G/5G wireless systems. Although there is a great amount of literature in the design of cognitive radios from a system and networking point of view, there has been very limited available literature detailing the circuit implementation of such systems. Our textbook, Radio Frequency Integrated Circuit Design for Cognitive Radios, is the first book to fill a disconnect in the literature between Cognitive Radio systems and a detailed account of the circuit implementation and architectures required to implement such systems. In addition, this book describes several novel concepts that advance state-of-the-art cognitive radio systems.

    标签: Cognitive Systems Design Radio RFIC for

    上传时间: 2020-05-31

    上传用户:shancjb

  • Scrambling Techniques for CDMA Communications

    With the advent of IMT-2000, CDMA has emerged at the focal point of interest in wireless communications. Now it has become impossible to discuss wireless communications without knowing the CDMA technologies. There are a number of books readily published on the CDMA technologies, but they are mostly dealing with the traditional spread-Spectrum technologies and the IS-95 based CDMA systems. As a large number of novel and interesting technologies have been newly developed throughout the IMT-2000 standardization process in very recent years, new reference books are now demanding that address the diverse Spectrum of the new CDMA technologies.

    标签: Communications Scrambling Techniques CDMA for

    上传时间: 2020-05-31

    上传用户:shancjb

  • Silicon-Based+RF+Front-Ends

    Ultra-wideband (UWB) technology enables high data-rate short-range communica- tion, in excess of hundredmegabit-per-secondsand up to multi-gigabit-per-seconds, over a wide Spectrum of frequencies, while keeping power consumption at low lev- els. This low power operation results in a less-interfering co-existence with other existed communication technologies (e.g., UNII bands). In addition to carrying a huge amount of data over a distance of up to 230 feet at very low power (less than 0.5mW), the UWB signal has the ability to penetrate through the doors and other obstacles that tend to reflect signals at more limited bandwidths and higher power densities.

    标签: Silicon-Based Front-Ends RF

    上传时间: 2020-05-31

    上传用户:shancjb

  • Spectrum+and+Energy+Efficient

    Heterogeneous Network (HetNet): A network that consists of a mix of macro cells and low-power nodes, e.g. Pico, Femto, Relay Node (RN) and Remote Radio Head (RRH)

    标签: Efficient Spectrum Energy and

    上传时间: 2020-05-31

    上传用户:shancjb

  • Transceiver and System Design

    T his book covers basic communications theory and practical imple- mentation of transmitters and receivers. In so doing, I focus on dig- ital modulation, demodulation methods, probabilities, detection of digital signals, and spread Spectrum system design and analysis. This book was written for those who want a good understanding of the basic prin- ciples of digital wireless communication systems, including spread spec- trum techniques. This book also provides a good intuitive and practical approach to digital communications. Therefore it is a valuable resource for anyoneinvolvedinwirelesscommunicationsandtransceiverdesignfordig- ital communications. The reader will gain a broad understanding of basic communication principles for transceiver design, digital communications, and spread Spectrum, along with examples of many types of commercial and military data link systems.

    标签: Transceiver System Design

    上传时间: 2020-06-01

    上传用户:shancjb