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A semi-blind joint data and channel estimation based receiver for meteor burst communication

Science in China(Series F) 2005年第2期48卷 137-150页

作者： LIZan CHANGYilin JINLijun CAIJueping StateKeyLaboratoryofIntegratedServicesNetworks XidianUniversityXi'an710071China STMicroelectronicsR&DCo. Ltd.Beijing100080China StateKeyLaboratoryofIntegratedServicesNetworks XidianUniversityXi'an710071China

According to the analysis of meteor burst communication (MBC) mechanism, a model of signal processing based on the structure of data frame is suggested for adaptive modulation and coding (AMC) of MBC system in this paper. There are two distinct modes of operation for signal processing: acquisition and tracking. The acquisition mode is a training period to initialize the channel estimation by frame header. The tracking mode is jointly to equalize payload data and to trace channel, where the principle of per-survivor processing (PSP) for maximum likelihood sequence detection (MLSD) is performed. A suboptimal method called D-PSP is adopted to save the computational time and memory size, which agrees with the slow-fading characteristic of meteor channel and makes the MLSD possible for adaptive modulation and coding of MBC system. Computer simulation results are included to support our development.

关键词： meteor burst communication adaptive modulation and coding per-survivor processing MLSD.

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Distributed Scalar Quantizers for Subband Allocation

Distributed Scalar Quantizers for Subband Allocation

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48th Annual Conference on Information Sciences and Systems (CISS)

作者： Boyle, Bradford D. Walsh, John MacLaren Weber, Steven Drexel Univ Dept Elect & Comp Engn Philadelphia PA 19104 USA

ISBN: (纸本)9781479930012

Efficient downlink resource allocation (e.g., subbands in OFDMA/LTE) requires channel state information (e.g., subband gains) local to each user be transmitted to the base station (BS). Lossy encoding of the relevant state may result in suboptimal resource allocations by the BS, the performance cost of which may be captured by a suitable distortion measure. This problem is an indirect distributed lossy source coding problem with the function to be computed representing the optimal resource allocation, and the distortion measuring the cost of suboptimal allocations. In this paper we investigate the use of distributed scalar quantizers for lossy encoding of state, where the BS wishes to compute the index of the user with the largest gain on each subband. We prove the superiority of a heterogeneous (across users) quantizer design over the optimal homogeneous quantizer design, even though the source variables are i.i.d.

关键词： Quantization rateless coding adaptive modulation and coding resource allocation

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Towards Layer Adaptation for Audio Transmission

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INTERNATIONAL JOURNAL OF INTERDISCIPLINARY TELECOMMUNICATIONS AND NETWORKING 2014年第4期6卷 35-41页

作者： Holub, Jan Slavata, Oldrich Soucek, Pavel Zisimopoulos, Odysseas Toumpakaris, Dimitris Kotsopoulos, Stavros Czech Tech Univ Prague Czech Republic Univ Patras Dept Elect & Comp Engn Wireless Telecommun Lab Elect & Comp Engn Patras Greece Univ Patras Dept Elect & Comp Engn Wireless Telecommun Lab Patras Greece

When audio is transmitted over the wireless channel, the quality of the audio depends on the signal-to-noise ratio (SNR). The purpose of this paper is to investigate if rate adaptation can be avoided, and a system can rely instead on the audio encoder and decoder to alleviate the effect of channel errors. To this end, the paper reports on a set of experiments on various combinations of channel conditions, constellation sizes and audio encoding used and on the final audio quality achieved. The Mean Opinion Score (MOS) is used for performance evaluation. The MOS values are generated using the ITU-T P. 862 (PESQ) and P. 863 (POLQA) algorithms, and also using tests by experts. The results support the common practice of adapting the physical layer parameters to changing channel conditions. However, in some cases, it is possible to maintain a constant rate without impacting significantly the quality of the audio. This means that the complexity associated with physical layer and audio rate adaptation can be avoided leading to simpler and more robust designs.

关键词： adaptive modulation and coding Audio Quality Bit-Error Rate Mean Opinion Score Perceptual Evaluation of Speech Quality Perceptual Objective Listening Quality Assessment

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MCS Selection Criteria Based on Performance Simulation for HSDPA

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Journal of Beijing Institute of Technology 2003年第4期12卷 407-411页

作者：杨小倩赵胜辉费泽松匡镜明 Department of Electronic Engineering

An adaptive modulation and coding (AMC) scheme integrated with multi-code transmission for high speed downlink packet access is presented and some modulation and coding scheme (MCS) selection criteria are proposed to maximize single user data rates. Based on link-level performance analysis, the MCS selection criteria are proposed with the constraints of QoS requirement, modulation level, channel coding rate and the number of available channelization codes. By allowing multiple transmission parameters changing, these criteria make the scheme more flexible to time-varying mobile channel with comparatively low complexity through a look-up table method. The AMC scheme is sensitive to the changes of channel condition and can save the channelization codes in an applicable way by applying these criteria.

关键词： high speed downlink packet access adaptive modulation and coding multi-code transmission modulation and coding scheme

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A Joint Rate Control and AMC Algorithm for adaptive Transmission Systems

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 12-16页

作者： Yang Yu Xue-Zhi Tan Yong-Gang Chi Lin Ma Yao Wang Communication Research Center Harbin Institute of Technology

The traditional communication system is effectively designed for the worst-case channel state and it can not use the spectral efficiently over the time-varying multipath channel. In order to improve the spectral efficiency and ensure robust and spectrally-efficient transmission over the time-varying multipath channel,a joint rate control and adaptive modulation and coding ( AMC) algorithm for adaptive transmission systems is proposed in this paper. Firstly,the proposed algorithm can formulate a modulation and coding scheme ( MCS) switching table according to the offline simulation results and the target bit error rate ( BER) . Then,the optimal MCS is selected in MCS switching table according to the channel state information ( CSI) and then passes to the transmitter and receiver to implement. So the adaptive system which always uses the optimal MCS to transmit signals uses the spectral efficiently. The simulation results validate the proposed algorithm and show that under the premise of meeting the target BER,the adaptive system performing the proposed algorithm has a higher average spectral efficiency ( ASE) than that of the non-adaptive system.

关键词： adaptive modulation and coding average spectral efficiency adaptive transmission system modulation and coding scheme switching table

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Effect of Imperfect Spectrum Sensing on Slotted Secondary Transmission: Energy Efficiency and Queuing Performance

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IEEE TRANSACTIONS ON COGNITIVE COMMUNICATIONS AND NETWORKING 2018年第4期4卷 764-772页

作者： Wang, Wen-Jing Yang, Hong-Chuan Univ Victoria Dept Elect & Comp Engn Victoria BC V8W 2Y2 Canada

In cognitive radio communication system, unlicensed secondary user (SU) can opportunistically transmit over the under-utilized spectrum of primary user. With interweave implementation, SU performs spectrum sensing on the target frequency band to detect transmission opportunity. Sensing errors can greatly affect the performance of secondary transmission. In this paper, we propose a discrete-time Markov model to characterize slotted secondary transmission process with imperfect spectrum sensing. The stationary distribution is then applied to total collision probability evaluation and energy efficiency optimization for secondary transmission. Assuming that SU adopts adaptive transmission, we also evaluate the queuing performance of slotted secondary transmission, based on a 2-D finite-state Markov chain. Selected numerical results are presented to illustrate the mathematical formulation and to validate our analytical results. We show that false alarm has significant effect on the secondary throughput, whereas miss detection only notably reduces the secondary throughput when the traffic intensity is low.

关键词： Slotted secondary transmission Markov chain imperfect spectrum sensing adaptive modulation and coding energy efficiency queuing performance analysis

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Cross-layer Design for Wireless Video Stream Transmission

Cross-layer Design for Wireless Video Stream Transmission

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IEEE Wireless Communications and Networking Conference (WCNC)

作者： Wang, Zheng Chen, Huifang Xie, Lei Wang, Kuang Zhejiang Univ Dept Informat Sci & Elect Engn Hangzhou 310027 Zhejiang Peoples R China

ISBN: (纸本)9781424463985

To provide reliable video stream transmission over wireless networks, we propose a cross-layer design model in this paper. In the proposed model, the adaptive modulation and coding parameters at the physical layer, the ARQ parameters at the data link layer and the application-layer forward error correction (A-FEC) parameters at the application layer are jointly designed. Our objective is to maximize the number of correctly decodable frames in a group of picture (GOP) according to the channel conditions and the GOP structure of the video stream. We also present a low-complexity bandwidth allocation algorithm for the A-FEC. The effectiveness of the proposed bandwidth allocation algorithm and the cross-layer design model was shown in the simulation results.

关键词： adaptive modulation and coding application-layer forward error correction cross-layer design wireless video stream transmission

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A Novel Two-step Channel Prediction Technique for Supporting adaptive Transmission in OFDM/FDD System

A Novel Two-step Channel Prediction Technique for Supporting...

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IEEE Global Telecommunications Conference (GLOBECOM 06)

作者： Ko, SangJun Heo, Joo Chang, KyungHi Inha Univ Grad Sch Informat Technol & Telecommun Inchon South Korea

ISBN: (纸本)9781424403561

This paper introduces a novel channel prediction technique for OFDM/FDD system to support adaptive modulation and coding (AMC) scheme over rapidly time-varying multipath fading channel. Most channel prediction techniques assume that there is no channel variation in the predefined time duration, e. g., a slot. As a result, those techniques can not compensate the degradation of packet error rate ( PER) performance resulting from the rapid variation of channel over the slot duration. In this paper, we propose a novel channel prediction technique that considers the time-varying nature of channel over the duration of interest. Simulation results show that the AMC scheme of OFDM/FDD system utilizing the proposed channel prediction technique can guarantee the target PER of 1% without any loss of system throughput compared with the case supported by the conventional channel prediction under ITU-R Veh A 30km/h.

关键词： adaptive modulation and coding Channel Prediction OFDM/FDD

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A Cross-layer WiMAX Scheduling Algorithm based on Genetic Algorithm

A Cross-layer WiMAX Scheduling Algorithm based on Genetic Al...

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7th Annual Conference on Communication Networks and Services Research

作者： Song, Jianfeng Li, Jiandong Li, Changle Xidian Univ Broadband Wireless Commun Lab Inst Informat Sci State Key Lab Integrated Serv Networks Xian Peoples R China

ISBN: (纸本)9781424441556

An efficient scheduling algorithm can enhance the quality of service(QoS) provided by IEEE802.16e Mobile WiMAX. In this paper, a Cross-Layer Scheduling Algorithm based on Genetic Algorithm (CLSAGA) under the Network Utility Maximization (NUM) concept is proposed to allocate resources for each service flow. The real coded genetic algorithm is employed to solve NUM optimization problem. adaptive modulation and coding (AMC) scheme and QoS category index of each service flow jointly decide the weights of utility functions to calculate the scheduling scheme of medium access control (MAC) layer. Simulation results show that this approach guarantees the QoS requirements and balances priorities of the mobile stations.

关键词： adaptive modulation and coding Cross-layer design Genetic Algorithm Mobile WiMAX

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Call Admission Control for Multimedia Connections in Interactive Satellite Networks 12

Call Admission Control for Multimedia Connections in Interac...

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12th IEEE International Conference on Green Innovation for Africon Renaissance (AFRICON)

作者： Imole, Olugbenga Walingo, Tom Takawira, Fambirai Univ KwaZulu Natal Howard Coll Sch Elect Elect & Comp Engn Durban South Africa Univ Witwatersrand Sch Elect & Informat Engn Johannesburg South Africa

ISBN: (纸本)9781479974986

This paper presents a Call Admission Control scheme for an Interactive Multimedia Satellite network that employs a link adaptation technique to overcome the effect of the time-varying characteristics of the satellite channel. By associating users' channel states to particular transmission parameters, the amount of resources required to satisfy user connection requirements will vary as the channel state varies. In the proposed system, adaptive modulation and coding (AMC) is employed for transmission over the time-varying wireless channel of the return link of an interactive satellite network. The proposed CAC policy therefore considers the effect of AMC in its operation. The results show that the performance of the system is better than that of systems that do not consider effects of the time-varying wireless channel of the return link.

关键词： adaptive modulation and coding Call Admission Control DVB-RCS Satellite

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