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Hybrid Full Frequency Precoding for Integrated Remote Wireless Sensor and Multibeam Satellite Networks

KSII TRANSACTIONS ON INTERNET AND INFORMATION SYSTEMS 2016年第6期10卷 2546-2566页

作者： Li, Hongjun Dong, Feihong Gong, Xiangwu Deng, Changliang Jia, Luliang Wang, Jingchao PLA Univ Sci & Technol Coll Commun Engn Nanjing 210007 Peoples R China Inst China Elect Syst Engn Co Beijing 100141 Peoples R China PLAAF 95899 Unit Beijing 100085 Peoples R China

This paper investigates an efficient transmission scheme for the remote wireless sensors to receive information which is rarely discussed in the integrated remote wireless sensor and multibeam satellite networks (IWSMSNs). The networks can be employed to exchange sensing information for emergency scenario, ocean scenario, and so on, which are isolated from available terrestrial networks. As the efficient transmission link is important to the IWSMSNs, we propose a hybrid full frequency (HFF) precoding by taking advantage of frequency reuse and multiple-input multiple-output (MIMO) precoding. Considering energy efficiency and sinks fairness are crucial to transmission link, thus the HFF precoding problems are formulated as transmit power minimization (TPM) and max-min fair (MMF) received signal to interference plus noise ratio (SINR) problems, which can be transformed to indefinite quadratic optimization programs. Then this paper presents a semi-definite programming (SDP) algorithm to solve the problems for the IWSMSNs. The promising potential of HFF for the real IWSMSNs is demonstrated through simulations.

关键词： hybrid full frequency precoding multiple-input multiple-output integrated remote wireless sensor and multibeam satellite networks semi-definite programming

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Performance analysis of spatial multiplexing MIMO-OFDM system with different equalisers and guard intervals

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INTERNATIONAL JOURNAL OF COMMUNICATION NETWORKS AND DISTRIBUTED SYSTEMS 2016年第2期17卷 147-163页

作者： Chiali, Imane Debbat, Fatima Bendimerad, Fethi Tarik Univ Tlemcen Fac Technol Dept Telecommun LTT Tilimsen 13000 Algeria Univ Mascara Fac Sci & Technol Dept Comp Sci Mascara 29000 Algeria

multiple-input multiple-output (MIMO) system is a very popular solution in the field of wireless communications, in order to improve the capacity and reliability of radio link. Nevertheless, during any transmission over fading channel, the performance of MIMO system is degraded due to the inter symbol interference (ISI). The combination of orthogonal frequency division multiplexing (MIMO-OFDM) and the use of equalisation at the reception have become very effective to eliminate the (ISI) and reduce the imperfection of the channel. The optimal maximum likelihood (ML) equaliser suffers from high computational complexity. In this context, we propose the combination of vertical bell labs space time (VBLAST) multiplexing and ordered successive interference cancellation (OSIC) equaliser in MIMO-OFDM system, whose performance is compared with different equalisers, in particular zero forcing (ZF), minimum mean square error (MMSE), and ML using cyclic prefix (CP) and zero padding (ZP) intervals in Rayleigh time-selective fading channel. The simulation results show that the performance of ZF/MMSE-OSIC equaliser with ZP-ODFM is close to the ML with a low complexity and it works better as compared to other algorithms.

关键词： multiple-input multiple-output MIMO vertical bell labs space time VBLAST spatial multiplexing orthogonal frequency division multiplexing OFDM cyclic prefix CP zero padding ZP ordered successive interference cancellation OSIC zero forcing ZF minimum mean square error MMSE maximum likelihood ML

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MIMO PCB-INTEGRATED SLOT ANTENNA FOR IEEE 802.11n WLAN ACCESS-POINT APPLICATIONS

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2016年第5期58卷 1254-1256页

作者： Lin, Chun-Cheng Huang, Chih-Yu ROC Air Force Acad Dept Math & Phys Sci Kaohsiung 820 Taiwan Natl Kaohsiung Normal Univ Dept Elect Engn Kaohsiung 802 Taiwan

A multiple-input multiple-output (MIMO) slot antenna integrated with a printed circuit board (PCB) is proposed for accesspoint (AP) applications. The antenna comprises two square slot radiators fed by mutually orthogonal 50-X microstrip lines. Through an appropriate adjustment of the antenna geometry parameters, a sufficient 210 dB return loss impedance bandwidth (similar to 21% at 2.43 GHz), a good radiating performance (i.e., high antenna peak gain values and stable radiation patterns), and a high isolation between the radiators can be achieved. The antenna is thus ideally suited for IEEE 802.11n (2.4 GHz) wireless local area network (WLAN) AP applications. (C) 2016 Wiley Periodicals, Inc.

关键词： access-point multiple-input multiple-output printed circuit board slot antenna wireless local area network

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Optimal detection in multiple-input multiple-output orthogonal frequency-division multiplexing systems with imperfect channel estimation

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IET COMMUNICATIONS 2010年第4期4卷 384-394页

作者： Zhang, J. Baronkin, V. M. Zakharov, Y. V. Univ York Dept Elect York YO10 5DD N Yorkshire England NN Andreev Acoust Inst Moscow Russia

An optimal detector for orthogonal frequency-division multiplexing (OFDM) signals with pilot symbol assisted modulation in multiple-input multiple-output (MIMO) frequency selective fading channels with imperfect channel estimation is derived. This detector does not estimate the channel explicitly but maximises the likelihood function incorporating received data and pilot symbols to recover the data. The authors investigate and compare its performance with that of mismatched detectors treating maximum likelihood (ML), regularised ML or minimum mean squared error (MMSE) channel estimates as perfect channel information in spatially uncorrelated MIMO channels with binary phase shift keying (BPSK) and 16-quadrature amplitude modulation (QAM) by simulation. The authors use basis functions to model the channel frequency response and compare the performance of different basis expansion models in frequency selective fading channels with different delay spread. In single-input single-output (SISO) channels, the performance of the optimal detector is close to that of the mismatched detector with MMSE channel estimates, which provides the best performance among these mismatched detectors. However, the optimal detector significantly outperforms the mismatched detectors in MIMO channels.

关键词： spatially uncorrelated MIMO channels maximum likelihood mismatched detectors pilot symbol assisted modulation multiple-input multiple-output least mean squares methods maximum likelihood estimation fading channels OFDM signals Modulation and coding methods BPSK quadrature amplitude modulation OFDM modulation likelihood function channel estimation SISO channel optimal detection single-input single-output orthogonal frequency division multiplexing systems QAM modulation MIMO frequency selective fading channels channel frequency response phase shift keying MMSE channel minimum mean squared error Interpolation and function approximation (numerical analysis) Radio links and equipment Communication channel equalisation and identification MIMO communication imperfect channel estimation

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Fine-Grained Indoor Localization Using Single Access Point With multiple Antennas

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IEEE SENSORS JOURNAL 2015年第3期15卷 1538-1544页

作者： Wen, Fuxi Liang, Chen Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore Xian Univ Posts & Telecommun Sch Comp Sci & Technol Xian 710121 Peoples R China

We propose a single access point-based fine-grained indoor localization system in multipath environments using 802.11ac Wi-Fi signals. The physical layer of 802.11ac supports orthogonal frequency-division multiplexing modulation (OFDM) scheme, more antennas, and multiuser multiple-input multiple-output. Angle-of-arrival (AOA) of the paths can be obtained using the phase difference among all the antennas. Similarly, time of arrival (TOA) information is estimated from the phase difference among all the subcarriers of the OFDM signal. After obtaining the AOA and TOA information of the dominant paths, an auto paring approach is proposed to identify the line-of-sight (LOS) path. Mobile device can be localized using the estimated AOA and TOA information of the LOS path. Performance analysis of the proposed method is provided. Numerical simulations are carried out to evaluate the performance. Based on the simulation results, meter or submeter level accuracy is obtained for the proposed method.

关键词： Indoor localization fine-grained multiple-input multiple-output angle of arrival time of arrival orthogonal frequency-division multiplexing channel frequency response access point mobile device line-of-sight

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Sum-rate maximisation for two-way AF MIMO relaying networks and random antenna selection

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International Journal of Communication Networks and Distributed Systems 2016年第1期16卷 16-28页

作者： Sayeb, Rahima Hamdi, Noureddine Manar Univ ENIT Commun Syst Lab BP 37 Tunis 1002 Tunisia Carthage Univ INSAT Dept Comp Sci & Math Ctr Urbain Nord BP 676 Tunis 1080 Tunisia

This paper considers a multiple-input multiple-output (MIMO) two-way relaying network, where two-source nodes exchange data via a half-duplex amplify-and-forward (AF) relay. In this paper, we propose an efficient random antenna selection strategy based on maximising the sum-rate and minimising the power consumption. The proposed strategy involves choosing the best transmit and receive antennas at the two sources based on the maximisation of the overall sum-rate. The key design criterion is to reduce transmit radio frequency chains in order to minimise the energy consumption of the system. In the first step, transmit and receive antennas will be selected randomly. In the second step, signal-to-noise ratios (SNRs) of randomly chosen antennas are compared with a predefined threshold gamma th. If the SNRs of the selected antennas are higher than the predefined threshold, these antennas will be chosen for the communication. Else another random selection is used. Also, we show that for the problem of sum-rate maximisation related to the introduced system, the optimal relay matrix have a general beamforming structure. Simulations demonstrate the performance of the proposed algorithm.

关键词： multiple-input multiple-output MIMO cooperation AF model two-way relaying TWR sum-rate maximisation

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Congestion control based ant colony optimization algorithm for large MIMO detection

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EXPERT SYSTEMS WITH APPLICATIONS 2015年第7期42卷 3662-3669页

作者： Mandloi, Manish Bhatia, Vimal Indian Inst Technol Indore Discipline Elect Engn Indore 453441 Madhya Pradesh India

Employing multiple antennas in wireless communication systems is a key technology for future generation of wireless systems. Symbol detection in multiple-input multiple-output (MIMO) systems with low complexity is challenging. The minimum bit error rate (BER) performance can be achieved by maximum likelihood (ML) detection. However, with increase in number of antennas in MIMO systems, the ML detection becomes impractical. For example, sphere decoder (SD) is a well known ML detector for MIMO systems, however because of its high complexity it is practical only up to 32 real dimensions. Recently, bio-inspired algorithms are being used for improving the BER performance of MIMO symbol detector, along with low complexity. In this article, we propose a congestion control based ant colony optimization (CC-ACO) algorithm for large MIMO detection. We also discuss the robustness of the proposed algorithm under channel state information (CSI) estimation error. The simulation results shows the effectiveness of the proposed algorithm in terms of achieving better bit error rate (BER) performance with low complexity. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Ant colony optimization multiple-input multiple-output Minimum mean squared error Zero forcing Channel estimation error Successive interference cancellation Maximum likelihood

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Space-Time-Range Adaptive Processing for Airborne Radar Systems

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IEEE SENSORS JOURNAL 2015年第3期15卷 1602-1610页

作者： Xu, Jingwei Zhu, Shengqi Liao, Guisheng Xidian Univ Natl Lab Radar Signal Proc Xian 710071 Peoples R China

Conventional phased-array space-time adaptive processing (STAP) radar combines angle and Doppler domains to realize clutter suppression. However, it suffers from severe performance degradation in electronic countermeasures scenarios, especially in the presence of mainbeam deceptive jamming. In this paper, a multiple-input multiple-output (MIMO) STAP radar is studied with a frequency diverse array (FDA) acting as the transmit array, which is referred to as FDA-MIMO STAP radar. FDA can provide controllable degrees of freedom in both range and angle domains. As a result, in FDA-MIMO STAP radar, the target can be discriminated from the clutter and jamming in joint range-angle-Doppler domains. By combining the range, angle and Doppler domains in FDA-MIMO STAP radar, a space-time-range adaptive processing method is proposed based on subspace projection technique. Simulation results demonstrate the effectiveness of the proposed approach in suppressing the clutter and jamming.

关键词： Space-time adaptive processing mainbeam deceptive jamming frequency diverse array multiple-input multiple-output range-angle-dependent

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On Adjacent Channel Interference Mitigation for Rotating MIMO Receivers

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2015年第10期14卷 5763-5779页

作者： Zaidel, Benjamin M. Mueller, Ralf R. Bar Ilan Univ Fac Engn IL-52900 Ramat Gan Israel Univ Erlangen Nurnberg Inst Digital Commun D-91058 Erlangen Germany

Virtually rotating antennas, which rotate once or several times during a symbol interval, have been considered in recent years as a compact (in volume) alternative for achieving additional degrees of freedom compared to standard multiple antenna receivers. Antenna rotation effectively induces bandwidth expansion at the receiver, which in turn increases the effective dimensionality, and may potentially allow for spatial multiplexing. However, in a licensed spectrum such bandwidth expansion also introduces interference from signals transmitted in adjacent frequency bands. This paper investigates to what extent such adjacent channel interference can be mitigated by appropriate signal processing. The potentially achievable throughput of systems employing multiple virtually rotating antennas is examined analytically in a multiuser setting, while considering the large system limit, and employing random matrix theory tools. The analysis focuses on the linear minimum mean-square error (MMSE) receiver, and a receiver that optimally decodes the transmissions of desired users, while being unaware of the codebooks of interferers. The achievable throughput is compared to the corresponding throughputs of standard multiple antenna receivers employing the same number of physical active antenna elements. Conditions for virtually rotating antennas to be beneficial are identified, which when met are shown to lead to significant performance enhancement over standard multiple antenna receivers.

关键词： Rotating antennas multiuser receivers interference mitigation multiple-input multiple-output random matrix theory

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MIMO OFDM Index Modulation with Circular-Shift-based Activation Pattern for Rapidly Time-Varying Channels

MIMO OFDM Index Modulation with Circular-Shift-based Activat...

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IEEE Vehicular Technology Conference

作者： Fangchao Yao Jianping Zheng Zhenzhou Li State Key Laboratory of Integrated Service Networks Xidian University

ISBN: (纸本)9781509016990

In this paper, the extension of the orthogonal frequency division multiplexing (OFDM) index modulation (IM) from single-antenna systems to multiple-antenna systems is studied. And a multiple-input multiple-output (MIMO) OFDM IM scheme with circular-shift-based activation pattern is proposed for the rapidly time-varying (RTV) channel. In the proposed scheme, the IM is applied in the joint antenna and sub-carrier dimension. Concretely, a constructive generation method of the IM pattern matrix based on the circular shift of a sparse column vector is presented, which makes the frequency-domain signal is sparse in both antenna and sub-carrier dimensions. The performance of the proposed scheme in the RTV channel is demonstrated by computer simulations.

关键词： multiple-input multiple-output Orthogonal frequency division multiplexing Index modulation Rapidly time-varying channel Orthogonal frequency division multiplexing multiple input multiple output systems ANTENNA SYSTEM column vector Instant messaging time-varying channels Subcarriers ANTENNA antennae ROOM TEMPERATURE VULCANISING Ritonavir

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