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Precoding and Transmitter-Side processing techniques for multiuser MIMO OFDM systems with special emphasis on the PAPR problem

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EURASIP JOURNAL ON ADVANCES IN SIGNAL PROCESSING 2011年第1期2011卷 1页

作者： Wunder, G. Fischer, R. F. H. Litsyn, S. No, J. S. Heinrich Hertz Inst Berlin Berlin Germany Univ Ulm Ulm Germany Tel Aviv Univ IL-69978 Tel Aviv Israel Seoul Natl Univ Seoul South Korea

Green information technology has significantly fuelled the discussion about energy efficiency in information networks. Already today, energy cost of network operation can make up as much as 50% of the total operational cost. Notably, by the complexity of networks in general, the efficiency problem is hard to tackle on a global scale but entails several important sub-problems. One of these sub-problems is the energy efficiency of the high-power amplifier (HPA) at the very end of the radio frequency chain of the physical layer [1]. The HPA consumes a major fraction of the total energy budget of which, depending on the efficiency class, still much is dissipated as thermal energy and therefore wasted. While smart HPA design can alleviate much of this process there is an intrinsic problem which depends on the form how the HPA is operated: high fluctuations of the input signal-typically quantified by means of the peak-to-average power ratio (PAPR)-enforce operating points typically well below an acceptable efficiency region. This problem becomes particularly serious in multicarrier syste

关键词： Orthogonal frequency division multiplexing prediction coding networked information Information Network Energy efficiency multiple input multiple output systems information technology radiofrequency Thermal energy Network operations Peak to average power ratio High power amplifiers Energy budget

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Transmit Precoding for MIMO-BICM-ID Satellite Systems with Nonlinear Power Amplifiers

Transmit Precoding for MIMO-BICM-ID Satellite Systems with N...

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WSA 2013;17th International ITG Workshop on Smart Antennas

作者： Thomas Delamotte Gerhard Bauch Vito Dantona Berthold Lankl Institute of Information Processing Universitat der Bundeswehr Munchen Institute of Communications Technische Universitat Hamburg-Harburg Institute of Communications Engineering Universitat der Bundeswehr Munchen

For power efficiency, High Power Amplifiers (HPAs) used in satellite communications must be operated as close as possible to saturation. This constraint especially results in nonlinear amplitude distortions of the transmit signals. In this paper, the impact of these distortions on the performance of a linearly precoded 2 x NR Multiple-Input-Multiple-Output (MIMO) Single Carrier Geostationary Earth Orbit (GEO) satellite system operated for fixed satellite services (FSS) and using PSK modulation is analyzed. In order to combine channel coding and modulation, a Bit-Interleaved-Coded-Modulation with Iterative Decoding (BICM-ID) scheme is considered. Through EXIT charts and BER simulations, it is shown that a phase precoder which aims at maximizing the input-output mutual information and doesnt increase the Peak-to-Average-Power-Ratio (PAPR) of the transmit signals, is a robust strategy in this context when QPSK symbols are used for bit-to-symbol mapping.

关键词： Satellite systems nonlinear power amplifier TRANSMITTING Map symbols Power amplifiers Satellite communication multiple input multiple output systems prediction coding Channel coding dynamic efficiency

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Fixed-complexity Vector Perturbation with Block Diagonalization for MU-MIMO Systems

Fixed-complexity Vector Perturbation with Block Diagonalizat...

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IEEE Malaysia International Conference on Communications

作者： Manar Mohaisen Bing Hui KyungHi Chang Seunghwan Ji Jinsoup Joung Inha University Graduate school of IT & T Innowireless Company

ISBN: (纸本)9781424455317;9781424455324

Block diagonalization (BD) is an attractive technique that transforms the multi-user multiple-input multiple-output (MU-MIMO) channel into parallel single-user MIMO (SU-MIMO) channels with zero inter-user interference (IUI). In this paper, we combine the BD technique with two deterministic vector perturbation (VP) algorithms that reduce the transmit power in MU-MIMO systems with linear precoding. These techniques are the fixed-complexity sphere encoder (FSE) and the QR-decomposition with M-algorithm encoder (QRDM-E). In contrast to the conventional BD VP technique, which is based on the sphere encoder (SE), the proposed techniques have fixed complexity and a tradeoff between performance and complexity can be achieved by controlling the size of the set of candidates for the perturbation vector. Simulation results and analysis demonstrate the properness of the proposed techniques for the next generation mobile communications systems which are latency and computational complexity limited. In MU-MIMO system with 4 users each equipped with 2 receive antennas, simulation results show that the proposed BD-FSE and BD-QRDM-E outperforms the conventional BD-THP (Tomlinson Harashima precoding) by 5.5 and 7.4dB, respectively, at a target BER of 10~(-4).

关键词： Multi-user MIMO Vector Perturbation Block Diagonalization Sphere Encoder QRD-M Encoder multiple input multiple output systems diagonalization ENCODER perturbation Transmitter power prediction coding multi-user

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AUTOCORRELATION-BASED ADAPTATION RULE FOR FEEDBACK EQUALIZATION IN WIDEBAND FULL-DUPLEX AMPLIFY-AND-FORWARD MIMO RELAYS

AUTOCORRELATION-BASED ADAPTATION RULE FOR FEEDBACK EQUALIZAT...

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IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Emilio Antonio-Rodriguez Roberto Lopez-Valcarce Taneli Riihonen Stefan Werner Risto Wichman Department of Signal Theory and Communications University of Vigo Vigo Spain Department of Signal Processing and Acoustics Aalto University Helsinki Finland

ISBN: (纸本)9781479903573

Simultaneous reception and transmission in the same frequency, so-called full-duplex operation, causes an infinite feedback loop in an amplify-and-forward relay. The unwanted echoes may result in oscillation at the relay, making it unstable, and distorting the spectrum. This paper presents an adaptive MIMO filtering method for full-duplex amplify-and-forward relays that aims at solving the joint problem of self-interference mitigation and equalization of the source-relay channel. The scheme exploits the knowledge of the autocorrelation of the transmitted signal as the only side information while allowing the relay, in the best case, to implement precoding as if there was not any self-interference or frequency selectivity in the source-relay channel. Finally, the proposed adaptation algorithm is investigated by determining its stationary points and by performing simulations in a MIMO-OFDM framework.

关键词： relay simultaneous reception FULL DUPLEX frequency selectivity self-interference prediction coding multiple input multiple output systems Feedback loop Equalization Feedback broadband duplex operation Autocorrelation Oscillations disturbance suppression

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MMSE-THP with QoS Requirements for the Downlink of Multiuser MIMO Systems

MMSE-THP with QoS Requirements for the Downlink of Multiuser...

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IEEE Vehicular Technology Conference

作者： Xinyang Guo Dewei Yang Hua Wang Jingming Kuang Xiaojie Wen School of Information and Electronics Beijing Institute of Technology Beijing China Beijing Institute of Satellite Information Engineering Beijing China

ISBN: (纸本)9781538663592;9781538663585

Tomlinson-Harashima precoding (THP) is a popular nonlinear interference mitigation technique employed at the transmitter side which can provide better performance in comparison with linear precoding technique with a slight increase in complexity. It can be considered as a dual to the successive interference cancellation (SIC). In this paper, we focus on a new THP scheme for the downlink of multiuser multiple-input multiple-output (MIMO) systems with decentralized receivers. In contrast to previous approaches, the proposed algorithm allows the provision of transmitting different types of information simultaneously subjected to different Quality of Service (QoS) requirements of each active user. This algorithm is based on minimum mean square error (MMSE) criterion and the closed-form solution of the processing matrices is found by applying Cholesky factorization with symmetric permutation. For this THP algorithm, by suitably ordering the rows of channel matrix we can obtain better performance. Moreover, it significantly improves the bit error rate (BER) performance as well as the achievable rate as compared with zero-forcing (ZF) THP available in the literature, which can be shown from simulation results.

关键词： error statistics interference suppression least mean squares methods matrix decomposition MIMO communication multiuser channels precoding quality of service Least squares method Quality of service prediction coding multiuser channels MIMO communication matrix decomposition multiple input multiple output systems suppression of interference Downlink information-type pirarubicin disturbance suppression Error analysis

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Efficient hybrid space-ground precoding techniques for multi-beam satellite systems

Efficient hybrid space-ground precoding techniques for multi...

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IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Nuan Song Tao Yang Martin Haardt Nokia Bell Labs China Shanghai China Communications Research Laboratory Ilmenau University of Technology Germany

ISBN: (纸本)9781509041183

Multi-beam mobile satellite systems aim at providing broadband and high speed mobile services over a large area to achieve a high system throughput, where hybrid space-ground beamforming is one of the most promising candidates for ground-based beamforming techniques. It not only reduces the feeder link bandwidth to save spectral resources, but also takes advantages of both the on-ground and on-board processing, exhibiting a good trade-off of the performance and the space/ground complexity. In this paper, we propose an efficient hybrid space-ground precoding technique for multi-beam mobile satellite systems. It consists of coarse on-board beamforming and reduced-rank on-ground beamforming based on the feed selection of the phased array antenna. The advantages of the proposed hybrid precoding are shown as compared to the fully on-ground beamforming as well as the existing solutions.

关键词： multi-beam mobile satellite systems on-ground beamforming on-board beamforming hybrid space-ground beamforming feed selection MIMO multi-beam multiple input multiple output systems Beamforming Satellite systems prediction coding mobile communication satellite HYBRID Hybrid electric vehicles

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Many Access for Small Packets Based on Precoding and Sparsity-aware Recovery

Many Access for Small Packets Based on Precoding and Sparsit...

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IEEE Global Communications Conference

作者： Ronggui Xie Huarui Yin Zhengdao Wang Xiaohui Chen Guo Wei Department of Electronic Engineering and Information Science University of Science and Technology of China Department of Electrical and Computer Engineering Iowa State University

ISBN: (纸本)9781509013296

Modern mobile terminals produce massive small data packets. For these short-length packets, it is inefficient to follow the current multiple access schemes to allocate transmission resources due to heavy signaling overhead. We propose a many-access scheme that is well suited for the future communication systems equipped with many receive antennas. The system is modeled as having a block-sparsity pattern with unknown sparsity level (i.e., unknown number of transmitted messages). Block precoding is employed at each single-antenna transmitter to enable the simultaneous transmissions of many users. The number of simultaneously served active users is allowed to be even more than the number of receive antennas. Sparsity-aware recovery is designed at the receiver for joint user detection and symbol demodulation. To better recover the transmitted block-sparse signal vector, interference cancellation based block orthogonal matching pursuit (ICBOMP) algorithm is developed upon the known BOMP algorithm for the recovery. Simulation results demonstrate the effectiveness of the proposed scheme in small packet services, as well as the advantages of ICBOMP in improving signal recovery accuracy and reducing computational cost.

关键词： prediction coding COMMUNICATION SYSTEMS Packet simultaneous transmission data packets Receiving antennas

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Pilot Contamination Precoding Assisted Sum Rate Maximization for Multi-cell Massive MIMO Systems

Pilot Contamination Precoding Assisted Sum Rate Maximization...

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WSA 2016;20th International ITG Workshop on Smart Antennas

作者： Jianhua Liu Yueheng Li Haixia Zhang Shuaishuai Guo Dongfeng Yuan

This paper focuses on the pilot contamination precoding (PCP) assisted sum rate maximization for multicell massive MIMO system with finite number of antennas at base station (BS). Considering the case where BSs with finite number of antennas, the impact of the noise, the channel estimation error, channel uncertainty caused by usage of statistical channel state information (CSI) and channel non-orthogonality on the system performance can not be neglected any more compared with the pilot contamination, we in this work jointly consider all these factors and formulate an optimization problem to maximize the sum rate of all users. We derive the expression of the PCP matrix maximizing sum rate (MSR) of all users. Based on the obtained expression, an iterative algorithm is proposed to get a suboptimal solution to maximize the sum rate of all users. Simulations have been done to verify its superiority and results show that the proposed MSR-PCP outperforms the existing zero forcing PCP (ZF-PCP) and max-min PCP with acceptable computational complexity, especially for the case where users are located at cell edges and suffer from strong interference.

关键词： multiple input multiple output systems Consumers sums pentachlorophenol Pneumocystis Pneumonia prediction coding System performance Pilots ANTENNA complexity classes Pollutant

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A Novel Massive MIMO Precoding Scheme for Next Generation Heterogeneous Networks

A Novel Massive MIMO Precoding Scheme for Next Generation He...

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IEEE Global Communications Conference

作者： Fengye Zhang Songlin Sun Bo Rong Fei Richard Yu Kejie Lu School of Information and Communication Engineering Beijing University of Posts and Telecommunications Communications Research Centre Department of System and Computer Engineering School of Information Carleton University Department of Electrical and Computer Engineering University of Puerto Rico at Mayaguez

ISBN: (纸本)9781479959532

Heterogeneous network (HetNet) is a promising technology to improve the capacity of future generations of cellular network, in which a mobile station can be served by multiple base stations (BSs) with different scales of coverage range, including short range low power nodes (LPNs). In HetNet, a major challenge is how to provide guaranteed quality-of-service (QoS) for all users. To address this issue, we investigate a practical scenario in which the massive multiple-input multiple-output (MIMO) technology is adopted by the cooperation of one macro-cell BS and several LPNs. Furthermore, we provide a lightweight channel state information (CSI) acquisition scheme for the implementation. Numerical simulation results demonstrate that the signal-to-interference-and noise ratio (SINR) of intended users in LPNs covered with small cells can be significantly increased by this proposed massive MIMO precoding scheme, whereas oppressing the impact on neighboring victim users.

关键词： Massive MIMO HetNets Precoding Channel estimation prediction coding channel estimation multiple input multiple output systems Heterogeneous networks mobile station

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Energy-Efficient Hybrid Precoding for Millimeter Wave Systems In MIMO Interference Channels

Energy-Efficient Hybrid Precoding for Millimeter Wave System...

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IEEE Vehicular Technology Conference

作者： Chunhua Ma Jianfeng Shi Nuo Huang Ming Chen National Mobile Communications Research Laboratory Southeast University

ISBN: (纸本)9781509016990

In this paper, we investigate energy-efficient hybrid precoding which consists of baseband precoding and radio frequency (RF) precoding for Millimeter Wave (mmWave) systems over multi-input multi-output (MIMO) interference channels. The considered optimization problem is intractable because both the object function and the constraint are non-convex. Instead of solving the multivariate optimization problem directly, we propose a near-optimal algorithm which includes two steps. First, the original problem is reformulated into an equivalent univariate optimization problem. Second, a near-optimal hybrid precoder is obtained via an orthogonal matching pursuit (OMP) based algorithm. Numerical results verify that the proposed hybrid precoding algorithm achieves a near-optimal EE performance. Moreover, the energy efficiency (EE) maximization algorithm outperforms the sum rate maximization algorithm in terms of the EE performance, especially at high transmit power.

关键词： Objective function prediction coding Interference channels Energy efficiency millimeter wave Transmitter power Optimization algorithms multiple input multiple output systems HYBRID Hybrid electric vehicles algorithms

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