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Time and Power Allocation for Collaborative Primary-Secondary Transmission Using superposition coding

IEEE COMMUNICATIONS LETTERS 2011年第2期15卷 196-198页

作者： Shin, Eun-Hee Kim, Dongwoo Hanyang Univ Dept Elect Engn & Comp Sci Ansan 426791 South Korea

This letter considers applying superposition coding (SC) in collaborative primary-secondary spectrum sharing environments where the secondary transmitter acts as a relay of the primary signal and is allowed to transmit its own signal only if it is not harmful to the primary transmission. Time and power allocation is optimized and numerical comparison shows that the proposed approach makes significant improvement in the achievable secondary rate.

关键词： Time and power allocation collaborative spectrum sharing superposition coding

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The Impact of the superposition coding Concept on Admission Control Strategy in OFDMA-Based Network

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China Communications 2018年第6期15卷 68-83页

作者： Yosra Abbes Sameh Najeh Hichem Besbes Research Laboratory COSIM Sup'Com University of Carthage

Admission control is a key mechanism to manage the increasing number of the simultaneous demanding services, requiring a desired Quality of Service(QoS) in a spectrum efficient manner. To address this issue,we investigate in this work, the use of the superposition coding technique to increase the system capacity through multiuser diversity exploitation. We propose a novel joint admission control and superposition coding formalism based on different utility functions:Opportunistic(OPSC), Great Fairness(GFSC)and Proportional Fairness(PFSC). Simulation results show the superiority of our proposed approaches over other by providing higher mean of served VoIP users and higher throughput while maintaining an average VoIP packet transmission delay lower than 0.6 ms.

关键词： admission control QoS superposition coding opportunistic great fairness proportional fairness VoIP users

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A cooperative diversity transmission scheme by superposition coding relaying for a wireless system with multiple relays

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WIRELESS NETWORKS 2015年第6期21卷 1801-1817页

作者： Liu, Yang Man, Yi Song, Mei Zhang, Hongtao Wang, Li Beijing Univ Posts & Telecommun Sch Elect Engn Beijing 100088 Peoples R China Beijing Univ Posts & Telecommun Sch Informat & Commun Engn Beijing 100088 Peoples R China

This paper proposes a cooperative diversity transmission scheme by superposition coding relaying (SC-relaying) for a wireless system with multiple relays. In this scheme, two layer signals, i.e., signal and , are transmitted from a base station (BS) in the first and the second time slot, while signal is also forwarded from multiple relays to a user in the second time slot. The two layer signals ( and ) meet and superimpose with each other in the air in the second time slot. Then successive interference cancellation (SIC) is used for decoding at the user. In this paper, the optimal power allocation that maximizes the sum throughput of and is first studied. Then the optimal number of selected relays and optimal transmission rate at the BS is derived. Finally the outage probability and diversity gain of the transmission of and is evaluated for system robustness. Simulation results show that the proposed scheme realizes the goal of increasing spectral efficiency and enhancing system robustness.

关键词： Cooperative diversity superposition coding Relay Power allocation Rate

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Interaction of multiplexing gains and power exponents allocation of two-level superposition coding relaying

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EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS 2011年第7期22卷 352-366页

作者： Jia, Xiangdong Yang, Longxiang Nanjing Univ Posts & Telecommun Minist Educ Key Lab Broadband Wireless Commun & Sensor Networ Nanjing 210003 Peoples R China Southeast Univ Natl Mobile Commun Res Lab Nanjing 210096 Peoples R China NW Normal Univ Coll Math & Informat Sci Lanzhou 730070 Peoples R China

A two-level rate superposition coding relaying (SC-relaying) scheme is discussed, in which only the relay-to-source channel state information feedback (CSF) is considered and, at source, a long power constraint is imposed on the basic signal S0 and the additional signal S1 whose multiplexing gains are r0 and r1, respectively. The CSF index is constructed based on the correct decoding of the signal S0 at relay. For the SC-relaying scheme, we propose a multilevel iteration constructing rule for the CSF index. With the proposed CSF constructing rule, the allocation method of the power signal-to-noise ratio exponents is first obtained by the investigation of the optimal outage exponent of the signal S0. Secondly, we obtain the value range of p11, p11 ???[1,1/r0], by studying the outage exponent lower bound of the signal S0, where p11 denotes the minimum of the power signal-to-noise ratio exponent of the signal S. Lastly, to observe the interaction between the multiplexing gains r0 and r1, we discuss the closed-form solution of the lower bound of the optimal outage exponent for the signal S1, through which we find that the multiplexing gain constraint is r1 ?=?1 -r0p11, p11 ?=?1. The substantial numerical analyses show that the results in this paper are reasonable. Copyright (c) 2011 John Wiley & Sons, Ltd.

关键词： wireless communications cooperative relaying superposition coding diversity-multiplexing tradeoff (DMT)

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High reliability of real-time visual data transmission using superposition coding with receiver diversity

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TELECOMMUNICATION SYSTEMS 2014年第2期57卷 107-118页

作者： Tahir, Yaseen Hasan Al-Hussaibi, Walid Ng, Chee Kyun Noordin, Nor Kamariah Ali, Borhanuddin Mohd Fdn Tech Educ Tech Coll Basrah Dept Elect Power Tech Engn Baghdad Iraq Univ Putra Malaysia Fac Engn Dept Comp & Commun Syst Engn Serdang 43400 Malaysia

Supporting visual data applications in the real-time communication systems are among the most challenging issues over the next generation wireless communication systems. This challenge is further magnified by the fact that the quality of reception is highly sensitive to transmission delay, data losses and bit error rate (BER) in such applications. In this paper, we proposed superposition coding with Receiver Diversity (SPC-RD) scheme, which employs unequal error protection (UEP) to improve the error performance, maximize the received signal to noise ratio (SNR) and optimize the reliability of the transmission system. In the transmitter side, the visual data is divided into a number of different priority layers based on their effects on the reception quality. These layers are modulated individually where the highest priority layer is modulated with the highest UEP level against error-prone channels, and vice versa. These modulated signals are then superimposed together and transmitted via wireless Single-Input Multiple-Output (SIMO) Rayleigh fading channel. In the receiver side, three different diversity combining approaches;selection combining (SC), equal gain combining (EGC) and maximal ratio combining (MRC) are considered. The combined signal is then passed through a multiuser demodulator so-called the ordered successive interference cancellation (O-SIC) demodulator to reconstruct and separate the data layers. This demodulation technique is evaluated and compared with the traditionally maximum likelihood joint detection (MLJD) technique. Extensive simulations have been carried out to validate the various assertions. Under the assumption of equal transmission power, the simulation results illustrate that the proposed SPC-RD scheme provides a SNR gain of 14.5 dB over the Rayleigh fading channel at the diversity order of three for the acceptable BER level of 10(-3) when BPSK scheme is exploited compared to the traditional equal error protection system. In addition, t

关键词： Real-time wireless data transmission Receiver diversity superposition coding UEP SIMO fading channels

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Design of a superposition coding PPM-DCSK System for Downlink Multi-User Transmission

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2020年第2期69卷 1666-1678页

作者： Ma, Huan Cai, Guofa Fang, Yi Chen, Pingping Chen, Guanrong Guangdong Univ Technol Sch Informat Engn Guangzhou 510006 Peoples R China Southeast Univ Natl Mobile Commun Res Lab Nanjing 210096 Peoples R China Fuzhou Univ Dept Elect Informat Fuzhou 350116 Peoples R China City Univ Hong Kong Dept Elect Engn Hong Kong Peoples R China

The conventional orthogonal multiple-access-based downlink transmission for the differential chaos shift keying system with pulse-position modulation (PPM-DCSK) suffers from lower energy efficiency and data rate. To tackle this problem, a low-complexity superposition coding PPM-DCSK (SC-PPM-DCSK) system for downlink multi-user chaotic communication is proposed in this paper. The proposed system exploits the superposition coding principle on the reference signal and the information-bearing signal to achieve multi-user simultaneous information transmission for the downlink scenario, thus significantly improving the energy efficiency and transmission rate. Furthermore, the analytical expression for the error performance and the throughput of the proposed system are precisely derived over additive white Gaussian noise and multipath Rayleigh fading channels. Simulation results not only verify the accuracy of the analytical method but also illustrate the proposed transmission scheme in achieving significant performance gain compared with the time-sharing-based PPM-DCSK and multiresolution DCSK systems. Due to such superiority, the proposed SC-PPM-DCSK system can be deemed to be an outstanding scheme for downlink multi-user short-range wireless communications.

关键词： Downlink Wireless communication Chaotic communication Receivers Encoding Modulation Fading channels Downlink multi-user transmission differential chaos shift keying superposition coding pulse position modulation multipath fading channel

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A Simple superposition coding Scheme for Optimizing Resource Allocation in Downlink OFDMA Systems

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WIRELESS PERSONAL COMMUNICATIONS 2011年第2期59卷 237-260页

作者： Najeh, Sameh Besbes, Hichem Ecole Super Commun Tunis Tunis Tunisia ISITC Sousse Tunisia

In this paper, we propose to apply a simple superposition coding strategy for downlink of OFDMA systems. The novelty of this paper consists on allowing at most two users to share the same subchannel. The main idea is to consider the subchannels allocated to the users with the weakest link, and allow these subchannels to be shared by some potential users who can transmit some number of bits with only a small amount of power. To decrease the overhead of the proposed OFDMA system, we restrict to use a predetermined superposition encoding|decoding scheme. We address the problem of resource allocation, which consists on finding the optimal subchannel assignment in the OFDMA system. A low complexity algorithm, denoted Share Specific Subcarrier Allocation (SSSA) is then proposed. It offers a fairness allocation among users. This can be done by taking into account all user's buffer states information. Simulation results confirm that the proposed technique outperforms the classical algorithms in terms of total throughput and dropping probability.

关键词： OFDMA system superposition coding Buffer overflow Fairness

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Minimum Power Multicast Beamforming With superposition coding for Multiresolution Broadcast and Application to NOMA Systems

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IEEE TRANSACTIONS ON COMMUNICATIONS 2015年第3期63卷 791-800页

作者： Choi, Jinho Gwangju Inst Sci & Technol GIST Sch Informat & Commun Kwangju 500712 South Korea

Multicast beamforming with superposition coding (SC) is studied for multiresolution broadcast where both data streams of high priority (HP) and low priority (LP) are to be transmitted for a user close to a base station (BS), while only data stream of LP is to be transmitted to a user not close to the BS (e.g., a cell-edge user). Using SC, a minimum total transmission power beamforming problem has been formulated to find beamforming vectors and powers for both users. For given normalized beamforming vectors, a closed-form expression for the optimal power allocation is derived from which an iterative algorithm is considered to find beamforming vectors. The proposed multicast beamforming with SC is applied to nonorthogonal multiple access (NOMA) systems to support multiple users as a two-stage beamforming method.

关键词： superposition coding multiresolution broadcast multicast beamforming

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Rate and power allocation for layered transmission with superposition coding

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IEEE SIGNAL PROCESSING LETTERS 2007年第11期14卷 773-776页

作者： Etemadi, Farzad Jafarkhani, Hamid Univ Calif Irvine Ctr Pervasive Communicat & Comp Dept Elect Engn & Comp Sci Irvine CA 92697 USA

We consider layered transmission of a Gaussian source over a quasi-static fading channel. A broadcast strategy is used in which multiple layers of source data are superimposed, and each layer is allocated a different power and transmission rate. For a multiple-antenna system where either the transmitter or the receiver has a single antenna, we propose a low-complexity algorithm for minimizing the expected end-to-end distortion of the received signal. Numerical results for a Rayleigh fading channel are presented, and the performance gain over a time-sharing strategy is quantified. It is numerically shown that for a wide range of operating conditions, equal rate allocation is as good as unequal rate allocation.

关键词： joint source-channel coding resource allocation superposition coding

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Transmission of Visual Data over Wireless Fading Channel in Real-Time Systems Based on superposition coding Scheme

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ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2013年第6期38卷 1459-1469页

作者： Tahir, Yaseen H. Ng, Chee Kyun Noordin, Nor K. Ali, Borhanuddin Mohd. Fdn Tech Educ Elect Power Engn Dept Basrah Tech Coll Basrah Iraq Univ Putra Malaysia Dept Comp & Commun Syst Engn Fac Engn Upm Serdang 43400 Selangor Malaysia

Real-time visual applications are among the most important requirements in the next generation wireless communication systems. In these applications, the transmitted data comprise different layers with different importance levels based on their influence on the reception quality. Furthermore, the real-time transmission nature of these applications makes them sensitive to data losses and transmission delay. To address these issues, an efficient superposition adaptive modulation and coding system, for the optimal system performance, is proposed in this paper. The proposed system switches its modulation and coding scheme adaptively to select the suitable modulation order and coding rate that best match with the instantaneous channel condition. The channel state information is estimated in receiver and fed back to transmitter. In such method, better performances in both data rate and bit error rate (BER) can be attained. Here, the source data are divided into different priority layers with different importance. Each layer bit stream is sent with specific error protection level against channel corruption. The highest error protection level is assigned to the highest priority layer, and vice versa. The modulated bit streams of all layers are then superimposed together and transmitted via Rayleigh fading channel. At the receiver side, a specific multi-stage decoding receiver is used to reconstruct the source data which demodulates the layers in the order of their priorities. Simulation results show that the proposed system provides up to 18 dB SNR and 46 % data rate gains, respectively, compared to the traditional BPSK scheme at BER of 10(-4).

关键词： Real-time wireless visual data transmission Fading channel superposition coding UEP AMC

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