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Relaying methods with high coding rate for wireless communications

JOURNAL OF COMMUNICATIONS TECHNOLOGY AND ELECTRONICS 2013年第12期58卷 1235-1240页

作者： Kahveci, Salim Karadeniz Tech Univ Fac Engn Dept Elect & Elect Engn TR-61080 Trabzon Turkey

A cooperative wireless relaying communication system usually consists of a source node, a destination node and one or more relay nodes. In this work Amplify-and-Forward/Decode-and-Forward relaying techniques are discussed in order to improve the performance of a wireless relaying communication system under the case of high code rate. As a performance metric, the outage probability of the proposed Amplify- and-Forward/Decode-and-Forward relaying structure is compared with and without coding issue. Results from the proposed modeling and simulations illustrate that our Amplify-and-Forward/Decode-and-Forward relaying method with high code rating enables robust cooperative wireless communication.

关键词： AF/DF relaying outage probability coding rate cooperative communication

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On Channel Capacity Estimation and Prediction for rate-Adaptive Wireless Video

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IEEE TRANSACTIONS ON MULTIMEDIA 2008年第7期10卷 1419-1426页

作者： Cho, Yongju Karande, Shirish Misra, Kiran Radha, Hayder Yoo, Jeongju Hong, Jinwoo Elect & Telecommun Res Inst Taejon 305350 South Korea Michigan State Univ Dept Elect & Comp Engn E Lansing MI 48824 USA

Packet drops caused by residue errors (MAC-layer errors) can severely deteriorate the wireless video quality. Prior studies have shown that this loss of quality can be circumvented by using forward error correction (FEC) to recover information from the corrupted packets. The performance of FEC encoded video streaming is critically dependent upon the choice of source and channel coding rates. In practice, the wireless channel conditions can vary significantly, thus altering the optimal rate choices. Thus, it is essential to develop an architecture which can estimate the channel capacity, and utilize this estimate for rate allocation. In this paper we develop such a framework. Our contributions consist of two parts. In the first part we develop a prediction framework that leverages the received packets' signal to silence ratio (SSR) indications and MAC-layer checksum as side information to predict the operational channel capacity. In the second part, we use this prediction framework for rate allocation. The optimal rate allocation is dependent upon the channel capacity, the distribution of the (capacity) prediction error and the rate-distortion (RD) characteristics of the video source. Consequently, we propose a framework that utilizes the aforementioned statistics for RD optimal rate adaptation. We exhibit the efficacy of the proposed scheme by simulations using actual 802.11 b wireless traces, an RD model for the video source and an ideal FEC model. Simulations using source RD models derived from five different popular video codecs (including H.264), show that the proposed framework provides up-to 5-dB improvements in peak signal-to-noise ratio (PSNR) when compared with conventional rate-adaptive schemes.

关键词： Channel quality prediction coding rate rate adaptation wireless LAN wireless video

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Redundancy-Optimal FF Codes for a General Source and Its Relationships to the rate-Optimal FF Codes

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2013年第12期E96A卷 2332-2342页

作者： Arimura, Mitsuharu Koga, Hiroki Iwata, Ken-ichi Shonan Inst Technol Dept Appl Comp Sci Fujisawa Kanagawa 2518511 Japan Univ Tsukuba Grad Sch Syst & Informat Engn Tsukuba Ibaraki 3058571 Japan Univ Fukui Grad Sch Engn Fukui 9108507 Japan

In this paper we consider fixed-to-fixed length (FF) coding of a general source X with vanishing error probability and define two kinds of optimalities with respect to the coding rate and the redundancy, where the redundancy is defined as the difference between the coding rate and the symbolwise ideal codeword length. We first show that the infimum achievable redundancy coincides with the asymptotic width W(X) of the entropy spectrum. Next, we consider the two sets C-(H) over bar(X) and C-W(X) and investigate relationships between them, where C-(H) over bar(X) and C-W(X) denote the sets of all the optimal FF codes with respect to the coding rate and the redundancy, respectively. We give two necessary and sufficient conditions corresponding to C-(H) over bar(X) subset of C-W(X) and C-W(X) subset of C-(H) over bar(X), respectively. We can also show the existence of an FF code that is optimal with respect to both the redundancy and the coding rate.

关键词： fixed-to-fixed length source coding information-spectrum methods general sources coding rate redundancy

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High Performance Speech Compression System

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Journal of University of Science and Technology Beijing 2001年第3期8卷 229-233页

作者： Ke Liu, Zhichun Mu, Zhong Wang Information Engineering School, University of Science & Technology Beijing, Beijing 100083, China Univ Sci & Technol Beijing Informat Engn Sch Beijing 100083 Peoples R China

Since Pulse Code Modulation emerged in 1937, digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel width without loss of speech quality remains a crucial problem in speech coding theory. A new full-duplex digital speech communication system based on the Vocoder of AMBE-1000(TM) and microcontroller ATMEL 89C51 is introduced. It shows higher voice quality than current mobile phone system with only a quarter of channel width needed for the latter. The prospective areas in which the system can be applied include satellite communication, IP Phone, virtual meeting and the most important, defence industry.

关键词： digital signal processing digital speech compression digital communication full-duplex coding rate

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Efficient approximate message authentication scheme

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IET INFORMATION SECURITY 2018年第1期12卷 100-106页

作者： Jiang, Shaoquan Li, Jue Liao, Yongjian Mianyang Normal Univ Inst Informat Secur Mianyang 621006 Peoples R China Zhejiang Gongshang Univ Sch Math & Stat Hangzhou 310018 Zhejiang Peoples R China Univ Elect Sci & Technol China Sch Software Engn Chengdu 610054 Sichuan Peoples R China

An approximate message authentication scheme is a primitive that allows a sender Alice to send a source state to a receiver Bob such that the latter is assured of its authenticity, where the source state is considered as authentic if it only undergoes a minor change. Here, the authors propose an efficient scheme for this problem and prove its security under a rigorous model. Our scheme only needs a lightweight computation cost and hence is very efficient. As the authentication message is transmitted over a noisy channel, we also value the channel efficiency (i.e. the coding rate). For a fixed coding method, this is determined by the admissible decoding bit error probability p(e). A larger p(e) admits a shorter codeword length and hence a larger coding rate. It turns out that the p(e) can be set to be a significantly large constant (determined by the legal distortion level for the source state). Compared with existing schemes, the advantage in p(e) is evident.

关键词： message authentication encoding error statistics approximate message authentication scheme sender Alice source state receiver Bob computation cost noisy channel channel efficiency fixed coding method admissible decoding bit error probability codeword length coding rate

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Improved low complexity hybrid turbo codes and union bound analysis

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IET COMMUNICATIONS 2011年第4期5卷 512-518页

作者： Bhise, A. Vyavahare, P. D. KJS Inst Engn & Informat Technol Dept Elect & Telecommun Engn Mumbai Maharashtra India SGS Inst Technol & Sci Dept Elect & Telecommun Engn Indore Madhya Pradesh India

Turbo convolutional codes (TCC) are excellent error correcting codes for wireless channels. However, TCC decoders require large decoding complexity. Moreover, complexity of TCC decoder does not reduce even if puncturing is used to change the coding rate. Modified turbo codes require lower decoding complexity than TCC as they use multiple concatenations of simple block codes and convolutional codes. Recently, a class of modified turbo codes called low complexity hybrid turbo codes (LCHTC) and improved low complexity hybrid turbo codes (ILCHTC) have been proposed. It has been shown that LCHTC and ILCHTC achieve bit error rate (BER) which is comparable to TCC and have much lower decoding complexity. Simulation results show that BER performance of ILCHTC is better than that of LCHTC. rate-1/3 ILCHTC achieve BER of 10(-5) at bit energy-to-noise ratio (E-b/N-0) of 1.9 dB, which is 0.4 dB higher than E-b/N-0 for TCC adopted by third generation partnership project (3GPP). Moreover, ILCHTC and LCHTC decoders require half the number of computations as compared to those required for TCC decoder. In this study, union-bound analysis of ILCHTC is presented to investigate BER performance <10(-6). For large interleaver lengths, analysis of theoretical union bound requires numerous computations. Therefore approximate analysis of union bound is derived from theoretical union bound. It is shown that the analysis of approximate union bound achieves reasonable accuracy. Moreover, approximate union bound can be evaluated with significantly less computational complexity than the theoretical union bound.

关键词： union bound analysis turbo convolutional codes wireless channel convolutional codes bit error rate error statistics Codes decoding complexity BER performance wireless channels decoding coding rate error correction codes third generation partnership project low complexity hybrid turbo codes turbo codes modified turbo codes computational complexity decoder error correcting codes Radio links and equipment Information theory Other topics in statistics

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Transceiver Design and Power Control for Full-Duplex Ultra-Reliable Low-Latency Communication Systems

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2022年第2期21卷 1392-1406页

作者： Singh, Keshav Biswas, Sudip Ku, Meng-Lin Flanagan, Mark F. Univ Coll Dublin Sch Elect & Elect Engn Dublin D04 V1W8 Ireland Indian Inst Informat Technol Dept Elect & Commun Engn Gauhati 781015 India Natl Cent Univ Dept Commun Engn Taoyuan 32001 Taiwan

Ultra-reliable low-latency communication (URLLC) is one of the most important components in the fifth generation (5G) cellular networks for realizing mission-critical applications. In this paper, we jointly optimize the transceiver design and decoding error probability (DEP) of a full-duplex (FD) URLLC system, where the base station (BS) operates in FD mode, while the uplink (UL) and downlink (DL) users work in half-duplex (HD) mode. Accordingly, an optimization problem is formulated to maximize the achievable total (UL plus DL) rate for an FD URLLC system under finite blocklength, subject to the end-to-end (E2E) reliability constraint from the UL user to each DL user and the total transmission power constraint at the UL user and at the BS. We analyze the problem structure and convexify the problem by approximating the channel dispersion in scenarios of high and mid-to-high signal-to-interference plus noise ratio (SINR) regimes, respectively. Next, efficient iterative algorithms are proposed to find the near-optimal power allocation for the UL user and transceiver weights for the BS. Furthermore, closed-form expressions of the transceiver weights are derived, and the convergence of the proposed algorithms is proved. Simulation examples demonstrate the impact of the code blocklength, number of DL users, transmitter/receiver distortion and DEP threshold on the system performance.

关键词： Ultra reliable low latency communication Wireless communication Transceivers Resource management Interference Optimization Signal to noise ratio Full-duplex (FD) finite blocklength codes ultra-reliable low-latency communication (URLLC) transceiver design power allocation coding rate uplink downlink optimization

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Cooperative DVB-SH Satellite Broadcasting Systems with Rotated Signal Constellations

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China Communications 2015年第6期12卷 59-72页

作者： Nikos C.Sagias Stylianos Papaharalabos P.Takis Mathiopoulos Department of Informatics and Telecommunications University of Peloponnese Laboratory of Wireless Communications Institute of Informatics and TelecommunicationsNational Centre for Scientific Research"Demokritos" Patriarhou Grigoriou and Neapoleos streetAgia Paraskevi15 310 AthensGreece Department of Informatics and Telecommunications University of Athens

In this paper,we study the advantages of cooperation in broadcasting systems from a geosynchronous earth orbit(GEO)satellite to mobile terminals(MTs),achieved through a terrestrial complementary ground station(CGS) with fixed installment,which acts as a *** and in the context of the digital video broadcasting-satellite-to-handheld(DVB-SH) standard,the performance improvements offered by the rotated constellations method are investigated,where prior transmission,a phase rotation of the transmitted symbols by a fixed angle is applied followed by a random component *** codes with soft decision decoding and appropriate random channel interleavers are also *** present analytical expressions for the bit log-likelihood ratios(LLRs)that are needed for soft decision decoding at the MT turbo decoder,while the code combining technique is adapted to improve the end-to-end(E2E) ***,we obtain through extensive computer simulations the average bit error probability(ABEP) of quadrature phase-shift keying(QPSK) signals received over pure land-mobile satellite(LMS)and pure CGS links for coding rates 1/3 and6/***,the optimal rotation angles are obtained for both links.E2 E ABEP results are then presented assuming cooperation between GEO and CGS,while the power allocation issue is investigated under fixed total transmission *** performance evaluation results show that by using the constellation rotation technique,a performance gain can be achieved for high coding rates.

关键词： broadcasting code combining constellation rotation coding rate comple-mentary ground system (CGS) coopera-tion digital video broadcasting satellite-to-hand-held (DVB-SH) decode-and-forward log-likelihood ratio (LLR) quadrature phase-shift keying (QPSK) orthogonal frequency-di-vision multiplexing (OFDM) relays satellitecommunications soft-decision decoding tur-bo codes random interleavers

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Capacity optimal design of two-hop relay network

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ELECTRONICS LETTERS 2010年第18期46卷 1295-U81页

作者： Cho, H. I. Hwang, G. U. Korea Adv Inst Sci & Technol Dept Math Sci Taejon 305701 South Korea Korea Adv Inst Sci & Technol Telecommun Engn Program Taejon 305701 South Korea

A decode-and-forward two-hop relay network exploiting spatial diversity is considered. By considering transmission overheads in detail to exploit spatial diversity, an explicit expression is derived for the average transmission capacity of the relay network, which is a function of the transmission time and coding rate by the source. Some numerical examples based on analysis are provided to demonstrate performance behaviour.

关键词： channel capacity coding rate decode-and-forward network diversity reception network transmission capacity spatial diversity transmission overheads two-hop relay network

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MULTIRING DIFFERENTIAL CHAIN CODES FOR LINE DRAWINGS

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ELECTRONICS LETTERS 1990年第10期26卷 677-678页

作者： JOHANNESSEN, AB BONS, JH WEYLAND, NBJ PRASAD, R Dept. of Electr. Eng. Delft Univ. of Technol. Netherlands

A new type of chain code, called multiring differential chain coding (MRDCC) is introduced. The coding rate is calculated and compared with standard chain coding (SCC), generalised chain coding (GCC), and differential chain coding (DCC). MRDCC offers the highest efficiency. Experimental observations are in good agreement with the theoretical results.

关键词： codes codes coding rate computer graphics computer graphics encoding line drawings multiring differential chain coding picture processing

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