Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article A Uniﬁed Approach to Optimal Opportunistic Spectrum Access under Collision Probability Constraint in Cognitive Radio Systems
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Admission Control and Interference Management in Dynamic Spectrum Access Networks
Introduction Harri Holma and Antti Toskala Mobile Voice Subscriber Growth Mobile Data Usage Growth Wireline Technologies Evolution Motivation and Targets for LTE Overview of LTE 3GPP Family of Technologies Wireless Spectrum New Spectrum Identiﬁed by WRC-07 LTE-Advanced LTE Standardization Antti Toskala Introduction Overview of 3GPP Releases and Process LTE Targets LTE Standardization Phases Evolution Beyond Release 8 LTE-Advanced for IMT-Advanced LTE Speciﬁcations and 3GPP Structure References System Architecture Based on 3GPP SAE Atte Länsisalmi and Antti Toskala System Architecture E...
In the latest years much research effort was devoted to envision a new paradigm for
wireless transmission. Results from recent works (Wireless Word Research Forum, 2005)
indicate that a possible solution would lie in utilizing in a more efficient manner the diverse
Radio Access Technologies1
(RATs) that are available nowadays, with the purpose of
enabling interoperability among them and convergence into one global telecom
infrastructure (beyond 3G).
Enable many mobile users to share simultaneously radio spectrum. Provide for the sharing of channel capacity between a number of transmitters at different locations. Aim to share a channel between two or more signals in such way that each signal can be received without interference from another.
When the first edition of WCDMA for UMTS was published by John Wiley & Sons, Ltd
6 years ago (in April 2000), 3GPP had just completed the first set of wideband CDMA
(WCDMA) specifications, called ‘Release 99’. At the same time, the Universal Mobile
Telecommunication Services (UMTS) spectrum auction was taking place in Europe.
UMTS was ready to go.
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)].
An Ad-hoc network or Independent Basic Service Set (IBSS) is a simple network where
communications are established between two or more wireless nodes or Stations ( STAs) in a
given coverage area without the use of an Access Point (AP) or server. The STAs recognize
each other and communicate directly with each other on a peer-to-peer level.
The growth in the use of mobile networks has come mainly with the third generation
systems and voice traffic. Withthe current third generation and the arrival of the 4G, the
number of mobile users in the world will exceed the number of landlines users. Audio
and video streaming have had a significant increase, parallel to the requirements of
bandwidth and quality of service demanded by those applications. Mobile networks
require that the applications and protocols that have worked successfully in fixed
networks can be used with the same level of quality in mobile scenarios.
Cognitive radio is a hot research area for future wireless communications in the recent years. In order to increase the spectrum utilization, cognitive radio makes it possible for unlicensed users to access the spectrum unoccupied by licensed users. Cognitive radio let the equipments more intelligent to communicate with each other in a spectrum-aware manner and provide a new approach for the co-existence of multiple wireless systems.
This book is published in print and online through the online OAPEN library (www.oapen.org).
OAPEN (Open Access Publishing in European Networks) is a collaborative initiative to
develop and implement a sustainable Open Access publication model for academic books in
the Humanities and Social Sciences. The OAPEN Library aims to improve the visibility and
usability of high quality academic research by aggregating peer reviewed Open Access
publications from across Europe.
Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2010, Article ID 598707, 11 pages doi:10.1155/2010/598707
Research Article Time-Frequency Spectrum Sharing Scheme for Next Generation OFDM Systems
Ayman Khalil, Matthieu Crussi` re, and Jean-francois H´ lard e ¸ e
European University of Brittany (UEB) and Institute of Electronics and Telecommunications of Rennes (IETR), INSA, 20 Avenue des Buttes de Co¨smes, 35708 Rennes, France e Correspondence should be addressed to Ayman Khalil, ayman.khalil@insa-rennes.
Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2011, Article ID 980805, 15 pages doi:10.1155/2011/980805
Research Article Optimal Multitaper Wigner Spectrum Estimation of a Class of Locally Stationary Processes Using Hermite Functions
Maria Hansson-Sandsten (EURASIP Member)
Mathematical Statistics, Centre for Mathematical Sciences, Lund University, P.O. Box 118, 221 00 Lund, Sweden Correspondence should be addressed to Maria Hansson-Sandsten, firstname.lastname@example.org.
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Medium Access in Spread-Spectrum Ad Hoc Networks with Multiuser Detection
The performance of current transport systems is inadequate when viewed in
terms of economic efficiency, sustainability, and safety. Towards Better Performing
Transport Networks examines the tools that are necessary to effectively
measure these systems and those that are required to improve them.
Utilising advanced tools of network analysis, the contributors challenge
various pieces of conventional wisdom and in particular the view that intermodal
transport is more environmentally benign than road transport.