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On integrating multiple access control and adaptive channel coding for cellular wireless voice and data services

COMPUTER COMMUNICATIONS 2001年第10期24卷 903-916页

作者： Lau, VKN Kwok, YK Univ Hong Kong Dept Elect & Elect Engn Hong Kong Hong Kong Peoples R China

In this paper, we introduce a novel technique to exploit the synergy between the multiple access control (MAC) layer and the physical layer of a cellular wireless system with integrated voice and data services. As in a traditional design, the physical layer (channel encoder and modulator) is responsible for providing error protection for transmitting the packets over the hostile radio channel while the MAC layer is responsible for allocating the precious bandwidth to the contending users for voice or data connections. However, a distinctive feature of our proposed design is that in the physical layer, a variable rate adaptive channel encoder is employed to dynamically adjust the amount of FEC according to the time-varying wireless channel state such that the MAC layer, which is a reservation-based TDMA protocol, is able to make informed decisions as to bandwidth allocation. Specifically, based on the channel state information provided by the physical layer, the MAC protocol gives higher priority to users with better channel states. This novel synergistic mechanism between the two protocol layers can utilize the system bandwidth more effectively. The multiple access performance of the proposed scheme is compared with two baseline systems and the well known DRMA protocol. The first baseline system consists of the same reservation-based MAC protocol but with a traditional fixed-rate physical layer. The second system consists of the same reservation-based MAC protocol and the same channel adaptive physical layer but without interaction between the two layers. All four protocols are incorporated with a request queue which stores the previous requests that survive the contention but are not allocated information slots. Our extensive simulation results demonstrate that significant performance gains are achieved through the exploitation of the synergy between the two protocol layers. (C) 2001 Elsevier Science B.V. All rights reserved.

关键词： multiple access control adaptive channel coding cellular wireless voice

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Joint design of adaptive channel coding and cell scheduling for wireless ATM

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ELECTRONICS LETTERS 2000年第6期36卷 549-551页

作者： Lau, VKN Kwok, YK Univ Hong Kong Dept Elect & Elect Engn Hong Kong Hong Kong Peoples R China

A novel packet scheduling algorithm for multimedia wireless ATM systems is proposed. The physical layer and packet scheduling layer are investigated. The physical layer (channel encoder) is responsible for protecting the ATM cells over the hostile radio channel while the ATM scheduler is responsible for allocating limited resources to the ATM cells for each virtual connection so as to meet the specified QoS requirements. The novelty of the scheme comes from the concept of joint design between the two layers. The mechanism of bi-directional interactions between the two layers is illustrated, taking into account time varying channel conditions. It is found that a significant performance improvement in the cell loss rate (CLR) and the mean cell delay (MCD) could be achieved for systems exploiting the joint design.

关键词： adaptive channel coding packet scheduling layer channel coding mean cell delay quality of service cell scheduling Communication switching packet switching physical layer Codes wireless ATM bi-directional interactions hostile radio channel joint design packet scheduling algorithm scheduling QoS requirements asynchronous transfer mode time varying channel conditions time-varying channels virtual connection cell loss rate adaptive codes

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Integration of adaptive Modulation and channel coding With Fountain coding for Packet Radio Systems

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IEEE TRANSACTIONS ON COMMUNICATIONS 2015年第5期63卷 1510-1521页

作者： Ellis, Jason D. Pursley, Michael B. Clemson Univ Clemson SC 29634 USA

We examine the integration of adaptive modulation and channel coding protocols with fountain coding in a packet radio system. We present three modes of operation for the adaptive transmission system, each of which adapts the channel code in a way that accommodates the fixed-length packets produced by the fountain encoder. Each mode works with the fountain coding system to mitigate the effects of time-varying fading on the radio links and provide high throughput.

关键词： adaptive channel coding adaptive modulation fountain coding packet radio

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adaptive Capacity-Achieving channel coding for Fountain-Coded Multicast Transmission in Packet Radio Systems

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2013年第12期12卷 6514-6526页

作者： Ellis, Jason D. Pursley, Michael B. Clemson Univ Clemson SC 29634 USA

For time-varying fading, adaptation of the physical-layer channel code greatly enhances the throughput of a multicast transmission system, even if the system employs an application-layer fountain code for packet erasure correction. Performance evaluations for adaptive channel-coding protocols typically require extensive simulations of the fading channel, the iterative decoding process, and the generation of the control information that is used for the adaptation of the channel code. We present a method for the evaluation of such protocols that avoids a substantial amount of the computation required by traditional simulations, and we demonstrate that some important performance measures can be evaluated entirely by analysis. By the use of capacity-achieving channel codes in our investigation, we also decouple the performance of the adaptive coding protocol from the performance of a particular type of channel code and decoding method, which facilitates comparisons among different protocols. The application of our methods is demonstrated for two adaptive channel-coding protocols that are candidates for fountain-coded multicast transmission in packet radio systems.

关键词： adaptive channel coding fountain coding multicast transmission packet radio

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adaptive RC QC-LDPC channel coding for Frequency Hopping Shallow Water Acoustic Communication

Adaptive RC QC-LDPC Channel Coding for Frequency Hopping Sha...

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Oceans Conference

作者： Lin, Meiying Xu, Xiaomei Chen, Yougan Zhang, Lan Xiamen Univ Minist Educ Key Lab Underwater Acoust Commun & Marine Informa Xiamen 361005 Peoples R China Xiamen Univ Coll Ocean & Earth Sci Xiamen Peoples R China

ISBN: (纸本)9781479936465

Shallow water acoustic (SWA) channels are fast varying spatially and temporarily according to environmental conditions. adaptive coding is appealing for SWA communications to improve the system efficiency by matching transmission parameters to channel variations. In this paper, we construct rate-compatible QC-LDPC (RC QC-LDPC) codes by extending information bits in frequency hopping (FH) SWA communication system. Combining actual channel impulse response measurement in Quangang Xiaocuo harbor, Fujian and Wuyuan bay, Xiamen, we build two SWA channels, and analyze the performances of RC QC-LDPC codes under different channel environment in FH-SWA communication system. Simulation results show that RC QC-LDPC codes can greatly reduce the bit error rate (BER) of the communication system, improve the system performance;The lower the code rate, the better the BER;The harsher the channel (such as longer channel delay, more multipath, lower signal-to-noise ratio), the lower the code rate is needed to meet system communication indicators;And look-up table of RC QC-LDPC code rate to meet communication performance indicator in FH-SWA system under different signal-to-noise ratio is given. The look-up table also calculates the data saving rate of RC QC-LDPC codes relative to 1/2 code rate. RC QC-LDPC codes in FH-SWA communication system can improve channel utilization, with flexible encoding and decoding, has good prospects in SWA communication.

关键词： communication technology adaptive channel coding RC QC-LDPC codes frequency hopping communication shallow water acoustic communication

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Delay-Throughput Enhancement in Wireless Networks With Multipath Routing and channel coding

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2011年第3期60卷 1116-1123页

作者： Ronasi, Keivan Mohsenian-Rad, Amir-Hamed Wong, Vincent W. S. Gopalakrishnan, Sathish Schober, Robert Univ British Columbia Dept Elect & Comp Engn Vancouver BC V6T 1Z4 Canada Texas Tech Univ Dept Elect & Comp Engn Lubbock TX 79409 USA

Multipath routing and adaptive channel coding are two well-known approaches that have been separately applied to wireless networks to improve the effective throughput. However, it is usually expected that achieving a high throughput would be at a noticeable cost of increasing the average end-to-end delay and causes major degradation in the overall network performance. In this paper, we show that a combination of multipath routing and adaptive channel coding can improve throughput and reduce delay and that it is possible to trade off delay for throughput and vice versa. This is in contrast to the general expectation that higher throughput can only be achieved with noticeable degradations in the end-to-end network delay. In this regard, we jointly formulate the end-to-end data rate allocation and adaptive channel coding (at the physical layer) within the general framework of network utility maximization (NUM). Depending on the choice of the objective function, we formulate two NUM problems: one aiming to maximize the aggregate network utility and another one aiming to maximize the minimum utility among the end-to-end flows to achieve fairness, which is of interest in certain vehicular network applications. Simulation results confirm that we can significantly decrease the average delay at the cost of a small decrease in throughput. This is achieved by maximizing the aggregate utility in the network when fairness is not the dominant concern. Furthermore, we also show that, even when resource allocation is performed to provide fairness, we can still decrease the maximum end-to-end delay of the network at the cost of a slight decrease in the minimum throughput.

关键词： adaptive channel coding delay-throughput tradeoff fairness link reliability multipath routing nonconvex optimization signomial programming utility maximization

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adaptive redundant residue number system coded multicarrier modulation

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2000年第11期18卷 2292-2301页

作者： Keller, T Liew, TH Hanzo, L Univ Southampton Dept Elect & Comp Sci Southampton SO17 1BJ Hants England

The novel class of nonbinary maximum minimum distance redundant residue number system (RRNS) codes is invoked in the context of adaptively RRNS coded, symbol-by-symbol adaptive multicarrier modulation, in order to combat the effects of frequency-selective fading inflicted by dispersive wide-band channels. The system's performance can be adjusted in order to maintain a given target bit error rate (BER) and bit per symbol (BPS) performance. The proposed adaptive RRNS scheme outperforms the convolutional constituent code based turbo coded benchmarker system for channel signal-to-noise ratios (SNR) in excess of about 15 dB at a target BER of 10(-4).

关键词： adaptive channel coding adaptive modulation adaptive OFDM coded multicarrier modulation OFDM redundant residue number system

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adaptive Transmission Protocols for Fountain-Coded Multicast in Packet Radio Networks

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IEEE TRANSACTIONS ON COMMUNICATIONS 2017年第4期65卷 1786-1796页

作者： Ellis, Jason D. Pursley, Michael B. Clemson Univ Clemson SC 29634 USA

Fountain coding is a valuable tool for multicast transmissions in half-duplex packet radio networks if it is supported by an adaptive transmission protocol that compensates for fluctuations in the propagation losses on the radio links. Our goal is to devise low-complexity packet-by-packet adaptive modulation and channel coding protocols that provide high throughput for a broad range of multicast channels and operate with limited feedback and no knowledge of the fade levels or even the probability distribution for the fading on the radio links. The only control information for the protocols is derived from simple receiver statistics that are obtained by the demodulators and channel decoders in the receiving radios. Performance results are presented for practical fountain coding with low-complexity adaptive modulation and channel coding. Results on ideal fountain coding with adaptive transmission based on hypothetical perfect channel-state information are employed as performance benchmarks.

关键词： adaptive channel coding adaptive modulation fountain coding packet radio

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Reconfigurable Rateless Codes

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2009年第11期8卷 5592-5600页

作者： Bonello, Nicholas Zhang, Rong Chen, Sheng Hanzo, Lajos Univ Southampton Sch Elect & Comp Sci Southampton SO17 1BJ Hants England

We propose novel reconfigurable rateless codes, that are capable of not only varying the block length but also adaptively modify their encoding strategy by incrementally adjusting their degree distribution according to the prevalent channel conditions without the availability of the channel state information at the transmitter. In particular, we characterize a reconfigurable rateless code designed for the transmission of 9,500 information bits that achieves a performance, which is approximately 1 dB away from the discrete-input continuous-output memoryless channel's (DCMC) capacity over a diverse range of channel signal-to-noise (SNR) ratios.

关键词： Reconfigurable rateless codes adaptive channel coding

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On adaptive hybrid error control in wireless networks using reed-solomon codes

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2005年第3期4卷 835-840页

作者： Yang, CQ Hossain, E Bhargava, VK Charles Schwab Rancho Palos Verdes CA 90275 USA Univ Manitoba Dept Elect & Comp Engn Winnipeg MB R3T 5V6 Canada Univ British Columbia Dept Elect & Comp Engn Vancouver BC V6T 1Z4 Canada

This letter models and analyzes an adaptive radio link level error control protocol using Reed-Solomon codes for wireless networks. Results show that the proposed dynamic rate adaptive strategy provides a much improve... 详细信息

关键词： adaptive channel coding hybrid-automatic repeat request (ARQ) error control Reed-Solomon (RS) codes

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