Download or read book Adaptive Transmission Protocols for Mobile Frequency Hop Radio Networks written by and published by . This book was released on 2003 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are reported on research in adaptive transmission for mobile wireless frequency-hop communication networks. Adaptive protocols were devised and performance results were obtained tor frequency-hop transmission with Reed-Solomon coding and frequency-hop transmission with turbo coding. A method for generating side information from interleaving was developed, and the performance of Hermitian codes was evaluated. Adaptive transmission protocols were integrated with adaptive routing protocols to provide energy efficiency in mobile, tactical, frequency-hop, wireless ad hoc networks.
Download or read book Routing in a Frequency hop Packet Radio Network with Adaptive Transmission written by Jeffrey S. Wysocarski and published by . This book was released on 1999 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adaptive Protocols for Frequency hop Packet Radio Networks written by Harlan Blair Russell and published by . This book was released on 1993 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Adaptive Transmission Protocol for Direct Sequence Spread Spectrum Packet Radio Networks written by Karthik Gajaraj and published by . This book was released on 2004 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wireless On Demand Network Systems written by Roberto Battiti and published by Springer Science & Business Media. This book was released on 2004-01-12 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the First IFIP TC6 Working Conference on Wireless On-Demand Network Systems, WONS 2004, held in Madonna di Campiglio, Italy in January 2004. The 25 revised full papers presented together with 7 short papers were carefully reviewed and selected from 77 submissions. The papers are organized in topical sections on localization and mobility management; MAC and radio resource management; Bluetooth scatternets; ad-hoc routing; security, applications, and service support; MAC analytical models; and on-demand Internet access.
Download or read book Performance Analysis of Reliable Adaptive Transmission for Mobile Radio Slow Frequency Hopping Channels Aided by Long Range Prediction written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to correlated fading in frequency hopping (FH) wireless communication systems, it is possible to predict the future channel state information (CSI) for one frequency based on the channel observations of other frequencies. As a result, the performance of slow FH systems can be improved by utilizing adaptive transmission techniques. We propose the optimal Minimum Mean Square Error (MMSE) Long Range Prediction algorithm for slow FH systems that employ coherent detection. A recursive autocorrelation update method and a simplified prediction algorithm are explored to reduce the complexity. Statistical model of the prediction accuracy is developed and used in the design of the reliable adaptive transmission systems. We investigate the performance of adaptive transmission for high-speed data transmission in SFH systems based on the proposed Long Range Prediction algorithms. For slow frequency hopping communications in the presence of partial-band interference, we propose to employ adaptive transmitter frequency diversity and adaptive modulation to mitigate the effects of partial-band interference and fading. Both standard Jakes model and realistic physical model are used to test the performance. Analysis and simulation results show that significant performance gains can be achieved relative to non-adaptive methods.
Download or read book Zu Wilhelm Weischedel written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Adaptive Protocols for Spread Spectrum Packet Radio Networks written by and published by . This book was released on 1989 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes research in adaptive protocols for spread- spectrum packet radio networks. Adaptive forwarding and routing protocols were developed and their performance was determined by simulation of a frequency-hop packet radio network with mobile partial-band jamming. New forwarding protocols were designed to permit short-term adaptation to changes in the interference environment in the network. A new routing technique, called least-resistance routing was developed, and various versions of this routing method were examined. Comparisons were made between different versions of least-resistance routing and between least-resistance routing and previously developed adaptive routing techniques. It was found that least-resistance routing is an effective way for dealing with mobile jamming in a frequency-hop packet radio network. Significant increases in throughput and end-to-end probability of success were obtained by use of least-resistance routing.
Download or read book Long Range Fading Prediction and Realistic Physical Modeling to Enable Adaptive Transmission for Mobile Radio Networks written by and published by . This book was released on 2005 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The feasibility of adaptive transmission enabled by Long Range Fading Prediction (LRP) was investigated for rapidly varying fading channels encountered in peer-to-peer mobile communication systems. The LRP algorithms were tested using the standard Jakes model and the realistic physical model developed by the Principal Investigators. This research was an interdisciplinary effort in communication theory, physics, and signal processing. Correlated fading was exploited in the development of the LRP algorithm to enable adaptive modulation for a Frequency Hopping Spread Spectrum (FH/SS) mobile radio channel. Adaptive frequency diversity transmission for FH systems with partial band interference also was explored. Significant performance gains were demonstrated relative to non-adaptive methods. Efficient channel loading for wireless Adaptive Orthogonal Frequency Division Multiplexing (AOFDM) systems aided by robust LRP was investigated and reduced feedback techniques were developed. The bit rates approaching those of AOFDM with perfect knowledge of fading conditions were achieved. Several linear and nonlinear Multi-Access Interference (MAI) mitigation and frequency diversity combining transmitter precoding methods aided by the LRP were developed for the downlink of the Direct Sequence Spread Spectrum (DS/SS) systems. The proposed techniques were shown to improve upon previously proposed precoding and detection methods while providing the desired performance/complexity trade-off.
Download or read book Adaptive WCDMA written by Savo G. Glisic and published by John Wiley & Sons. This book was released on 2003-07-25 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: CDMA (Code Division Multiple Access) is one type of multiple access system used in radio communication. Other multiple access methods include TDMA, FDMA, etc. WCDMA (Wideband Code Division Multiple Access) is the main air interface used for third generation mobile communication systems - UMTS (Universal Mobile Telecommunication System) and is characterised by a wider band than CDMA. WCDMA uses a wider radio band than CDMA, which was used for 2G systems, and has a high transfer rate and increased system capacity and communication quality by statistical multiplexing, etc. WCDMA efficiently utilises the radio spectrum to provide a maximum data rate of 2 Mbit/s. Third generation mobile communication systems are scheduled for operational startup in Japan and Europe in 2001-2002. Applying high-speed data transfer and state-of-the-art radio terminal technology, third generations systems enable multimedia and are currently in the process of being standardised under 3GPP. Among the three types of system to be standardised (i.e. WCDMA, MC-CDMA, UTRA TDD), Japan and Europe will adopt WCDMA in a strategy to take the lead through superior service. This volume will cover the latest theoretical principles of WCDMA and explain why these principles are used in the standards. Starting with a general overview, the more advanced material is then gradually introduced providing an excellent roadmap for the reader. * Presents comprehensive coverage of the theoretical and practical aspects of WCDMA * Provides a detailed roadmap by presenting the material step-by-step for readers from differing backgrounds * Systematically presents the latest results in the field Ideal for Engineers, academics and postgraduate students involved in research and development, engineers involved in management and administration.
Download or read book Adaptive Transmission and Channel Modeling for Frequency Hopping Communications written by and published by . This book was released on 2009 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project focused on design of adaptive transmission methods enabled by the long range fading prediction (LRP) for several mobile radio systems. First, a new improved allocation algorithm was proposed for multicarrier code-division multiple access (MC-CDMA) system with adaptive frequency hopping. When combined with multiuser detection, the proposed system is very efficient in mitigating the fading and multi-access interference for realistic mobile radio channels.
Download or read book Cognitive Wireless Communication Networks written by Ekram Hossain and published by Springer Science & Business Media. This book was released on 2007-10-23 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a unified view on the state-of-the-art of cognitive radio technology. It includes a set of research and survey articles featuring the recent advances in theory and applications of cognitive radio technology for the next generation (e.g., fourth generation) wireless communication networks. The contributed articles cover both the theoretical concepts (e.g., information-theoretic analysis) and system-level implementation issues.
Download or read book Adaptive Protocols for Mobile Wireless Networks written by and published by . This book was released on 2005 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are reported for basic research in mobile wireless communication networks for tactical applications including investigations of new methods for error-control coding and decoding, modulation and demodulation, channel access, adaptive transmission and routing, and broadband antenna design. Research results are presented on adaptive, energy-efficient, distributed protocols for mobile wireless networks that must operate effectively over unreliable communication links in highly dynamic environments and handle multimedia traffic. The dominant feature of the research is the exploitation of interactions among protocols to capitalize on the opportunities and overcome the impediments presented by the tactical communications environment and capitalize on the differences in quality-of-service requirements for mixed-media traffic. The interactions among protocols involve not only the exchange of information but also the active cooperation of different classes of protocols to accomplish the common objective of reliable, energy-efficient distribution of information. The research accomplishments include establishing and taking maximum advantage of a strong coupling of the various protocol layers with physical-layer functions such as receiver processing, modulation and demodulation, error-control coding and decoding. New protocols have been developed and evaluated for directional antennas, and broadband antennas have been designed and tested for use with spread-spectrum communications and other wideband waveforms. The development of side information in physical-layer operations and its effective utilization in soft-decision decoding, adaptive transmission, and adaptive routing are fundamental elements of the communication techniques and adaptive protocols that have been designed and evaluated.
Download or read book MILCOM 98 written by and published by . This book was released on 1998 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Link Adaptation for Relay Based Cellular Networks written by Basak Can and published by CRC Press. This book was released on 2022-09-01 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cover TextLink Adaptation for Relay-Based Cellular Networks focuses on the implementation of various link adaptation methods in OFDM(A) (Orthogonal Frequency Division Multiplexing/Multiple Access)?Time Division Duplex (TDD) based two-hop cellular networks. The analysis and design consider infrastructure based relays. New link adaptive transmission methods which dynamically select the channel coding, modulation, forwarding, relaying mechanisms and the packet size have been designed and evaluated for such networks. The selection among various schemes is based on maximizing the end-to-end throughput.This book provides a channel adaptive scheduler which considers the multiplexing loss caused by the two-phase nature of wireless relaying. The scheduler dynamically schedules the users on the frequency-time radio resources with efficient Modulation and Coding Schemes (MCS)s selected by Adaptive Modulation and Coding (AMC). Relaying is used only if it can provide throughput enhancement. The guidelines for efficient deployment of infrastructure based relay terminals are given. For the two-hop cellular communication systems, the system level performance of various cooperative diversity schemes has been investigated with the scheduler developed and the relays efficiently deployed in the cell. This investigation for low mobility scenarios shows that, a simple cooperative diversity scheme that dynamically chooses the best scheme among direct transmission and two-hop conventional relaying is a promising choice when compared to various more complex cooperative diversity schemes.In this book, a hop adaptive Medium Access Control (MAC)-Protocol Data Unit (PDU) size optimization is proposed for wireless relay networks.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cognitive Radio Software Defined Radio and Adaptive Wireless Systems written by Hüseyin Arslan and published by Springer Science & Business Media. This book was released on 2007-08-17 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Today’s wireless services have come a long way since the roll out of the conventional voice-centric cellular systems. The demand for wireless access in voice and high rate data multi-media applications has been increasing. New generation wireless communication systems are aimed at accommodating this demand through better resource management and improved transmission technologies. This book discusses the cognitive radio, software defined radio, and adaptive radio concepts from several perspectives.
