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Optimal Transmit Power Allocation for MIMO Two-Way Cognitive Relay Networks with multiple Relays using AF Strategy

IEEE WIRELESS COMMUNICATIONS LETTERS 2014年第1期3卷 30-33页

作者： Alsharoa, Ahmad Ghazzai, Hakim Alouini, Mohamed-Slim King Abdullah Univ Sci & Technol Comp Elect & Math Sci & Engn CEMSE Div Elect Engn Program Thuwal Makkah Province Saudi Arabia

In this letter, we consider a multiple-input multiple-output two-way cognitive radio system under a spectrum sharing scenario, where primary and secondary users operate on the same frequency band. The secondary terminals aims to exchange different messages with each other using multiple relays where each relay employs an amplify-and-forward strategy. The main objective of our work is to maximize the secondary sum rate allowed to share the spectrum with the primary users by respecting a primary user tolerated interference threshold. In this context, we derive an analytical expression of the optimal power allocated to each antenna of the terminals. We then discuss the impact of some system parameters on the performance in the numerical result section.

关键词： Two-way cognitive radio multiple-input multiple-output amplify-and-forward

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WIDEBAND LOOP ANTENNA USING DISTRIBUTED ELEMENTS FOR 4G MIMO MOBILE APPLICATION

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2014年第3期56卷 577-581页

作者： Zhao, Xing Choi, Jaehoon Hanyang Univ Dept Elect & Commun Engn Seoul 133791 South Korea

Wideband loop antennas with distributed elements are proposed for a fourth generation (4G) multiple-input multiple-output (MIMO) mobile terminal. The MIMO antenna system consists of two wideband loop antenna elements (Elements #1 and #3), working in the LTE Band 7 (0.88–0.96 GHz), and a printed U-shaped monopole antenna element (Element #2), operating in the WiMAX/WLAN bands (2.0–2.8 GHz). To improve the performances of antenna elements, the distributed elements are employed to reduce the antenna volume, to realize the wideband property, and to modify the input impedance of antenna elements. The arrangement of each antenna element is carefully justified and each element is located at different corners of the ground plane to improve the isolation and envelope correlation coefficient (ECC) characteristics. The MIMO antenna has an ECC lower than 0.1 and isolation higher than 11 dB over the frequency bands of interest. ? 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:577–581, 2014

关键词： loop multiple-input multiple-output mobile wideband fourth generation

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LOW-COMPLEXITY DETECTION AND TRANSMIT ANTENNA SELECTION FOR SPATIAL MODULATION

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SAIEE AFRICA RESEARCH JOURNAL 2014年第1期105卷 4-12页

作者： Pillay, N. Xu, H. Univ KwaZulu Natal Sch Engn Dept Elect Elect & Comp Engn King George V Ave ZA-4041 Durban South Africa

In this paper, we propose a novel low-complexity detection technique for conventional Spatial Modulation (SM). The proposed scheme is compared to SM with optimal detection (SMOD), SM with signal vector based detection (SM-SVD) and another reduced complexity detection technique, presented in the literature. The numerical results show that the proposed scheme can match the error performance of SM-OD very closely, even at low bit-error rate (BER). The computational complexity at the receiver, is shown to be independent of the symbol constellation size, and hence, offers a much lower complexity compared to existing schemes. To further improve the error performance, we then propose two closed-loop transmit antenna selection (TAS) schemes for conventional SM. We assume the receiver has knowledge of the channel and a perfect low-bandwidth feedback path to the transmitter exists. From evaluation of the BER versus normalized signal-to-noise ratio (SNR) and the complexity analysis, the proposed schemes exhibit a significant improvement over SM-OD and other improved SM schemes in terms of error performance and/or complexity.

关键词： Spatial modulation transmit antenna selection multiple-input multiple-output adaptive spatial modulation reduced complexity detection signal vector based detection optimal detection

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multiple-Antenna Interference Channels With Real Interference Alignment and Receive Antenna Joint Processing Based on Simultaneous Diophantine Approximation

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IEEE TRANSACTIONS ON INFORMATION THEORY 2014年第8期60卷 4757-4769页

作者： Zamanighomi, Mahdi Wang, Zhengdao Iowa State Univ Dept Elect & Comp Engn Ames IA 50011 USA

In this paper, the degrees of freedom (DoF) regions of constant coefficient multiple antenna interference channels are investigated. First, we consider a K-user Gaussian interference channel with M-k antennas at transmitter k, 1 <= k <= K, and N-j antennas at receiver j, 1 <= j <= K, denoted as a (K, [M-k], [N-j]) channel. Relying on a result of simultaneous Diophantine approximation, a real interference alignment scheme with joint receive antenna processing is developed. The scheme is used to obtain an achievable DoF region. The proposed DoF region includes two previously known results as special cases, namely: 1) the total DoF of (K, [N], [N]) interference channel with K users and N antennas at each node is NK/2 and 2) the total DoF of a (K, [M], [N]) channel is at least KMN/(M + N). We next explore constant-coefficient interference networks with K transmitters and J receivers, all having N antennas. Each transmitter emits an independent message and each receiver requests an arbitrary subset of the messages. Employing the novel joint receive antenna processing, the DoF region for this setup is obtained. We finally consider wireless X networks where each node is allowed to have an arbitrary number of antennas. It is shown that the joint receive antenna processing can be used to establish an achievable DoF region, which is larger than what is possible with antenna splitting. As a special case of the derived achievable DoF region for constant coefficient X network, the total DoF of wireless X networks with the same number of antennas at all nodes and with joint antenna processing is tight while the best inner bound based on antenna splitting cannot meet the outer bound. Finally, we obtain a DoF region outer bound based on the technique of transmitter grouping.

关键词： Interference channels interference alignment multiple-input multiple-output degrees of freedom region X network Diophantine approximation

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Performance of Overloaded MIMO-OFDM System with Repetition Code

Performance of Overloaded MIMO-OFDM System with Repetition C...

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International Symposium on Intelligent Signal Processing and Communication Systems (ISPACS)

作者： Matsuoka, Hikari Doi, Yoshihito Yabe, Tatsuro Sanada, Yukitoshi Keio Univ Dept Elect & Elect Engn Yokohama Kanagawa Japan

ISBN: (纸本)9781479961207

This paper investigates the performance of an overloaded multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system with a repetition code. It has been demonstrated that diversity with block coding prevents the performance degradation induced by signal multiplexing. However, the computational complexity of a joint decoding scheme increases exponentially with the number of multiplexed signal streams. Thus, this paper proposes the use of a repetition code in the overloaded MIMO-OFDM system. In addition, QR decomposition with M-algorithm (QRM) maximum likelihood decoding (MLD) is applied to the decoding of the repetition code. QRM-MLD significantly reduces the amount of joint decoding complexity. In addition, virtual antennas are employed in order to increase the throughput that is reduced by the repetition code. It is shown that the proposed scheme reduces the complexity by about 1/48 for 6 signal streams with QPSK modulation while the BER degradation is less than 0.1dB at the BER of 10(-3).

关键词： MIMO communication OFDM modulation error statistics maximum likelihood decoding BER degradation QR decomposition with M-algorithm QRM maximum likelihood decoding block coding computational complexity joint decoding scheme multiple-input multiple-output multiplexed signal streams orthogonal frequency division multiplexing overloaded MIMO-OFDM system repetition code signal multiplexing virtual antennas Computational modeling Decoding Encoding Joints multiplexing Throughput Transmitting antennas repetition coding Orthogonal frequency division multiplexing Block codes multiple input multiple output systems maximum likelihood decoding multipleXOR DECODING transmitting antennas MIMO communication Throughput decoding scheme Computational modeling Joints Joints complexity classes

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Simultaneous Provision of two MIMO Wireless and Baseband Wired Services in a Single Wavelength 5

Simultaneous Provision of two MIMO Wireless and Baseband Wir...

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5 International Conference on Photonics (ICP)

作者： Elmagzoub, M. A. Mohammad, A. B. Shaddad, R. Q. Al-Gailani, S. A. Univ Teknol Malaysia Fac Elect Engn LCRG Skudai Kagawa Malaysia

ISBN: (纸本)9781479948833

Next-generation access networks require simultaneous provision of wired and wireless services and high data rate to meet the huge demands for mobility and multiple services. In this paper, we propose a spectral efficient radio over fiber scheme to simultaneously provide two spatial multiplexed multiple input multiple output (MIMO) wireless signals with baseband (BB) signal in one wavelength using a centralized light source. The proposed scheme can be applicable in wavelength division multiplexed passive optical network (WDM-PON). The BB signal is modulated at low extinction ratio. Using the same modulated light, the two MIMO signals that have the same career frequency are combined optically using polarization-division-multiplexing (PDM). The BER performance of 10(-9) is achieved for the three signals after transmission of 20 km single mode fiber (SMF).

关键词： Next generation PON polarization multiplexing radio-over-fiber multiple-input multiple-output

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COMPARATIVE STUDY OF ADAPTIVE FILTER CHANNEL ESTIMATION TECHNIQUE IN MIMO-OFDM SYSTEM BASED ON STBC 13

COMPARATIVE STUDY OF ADAPTIVE FILTER CHANNEL ESTIMATION TECH...

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International Conference on Machine Learning and Cybernetics

作者： Li, Mei Wang, Xiang Zhang, Kun Hebei Univ Sci & Technol Inst Informat Sci & Engn Shijiazhuang 050018 Peoples R China

ISBN: (纸本)9781479942152

In this paper, we will analyze the Least Mean Square(LMS) and Recursive Least Square(RLS) algorithms. Then, we apply these two algorithms toa multiple-input multiple-output(MIMO-OFDM) system based on Space-Time Block Coding(STBC), and do some simulations on these two algorithms. From the simulation, it is found that the convergence speed of the RLS algorithm is faster than LMS algorithm, i.e., the performance of RLS is better than LMS algorithm.

关键词： multiple-input multiple-output Orthogonal frequency division multiplexing Channel estimation Adaptive filter algorithm

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Performance Analysis of Nakagami-m MIMO Channel in the Presence of multiple Keyhole

Performance Analysis of Nakagami-<i>m</i> MIMO Channel in th...

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International Conference on Information Networking (ICOIN)

作者： Islam, Md Muzahidul Hague, Md Razibul Islam, Md Rezaul Mostafa, Md Golam MIST Dept EECE Dhaka Bangladesh

ISBN: (纸本)9781479936892

In this contribution, we analyze the average symbol error rate (SER) of space-time block coded (STBC) multiple-input multiple-output (MIMO) system over Nakagami-m fading channel with M-PSK constellation in the presence of multiple keyholes. We derived the expression of channel transmission matrix which was further statistically analyzed to find the probability density function (PDF) of instantaneous signal to noise ratio (SNR) for the channel containing multiple keyholes between it's source and destination end. By performing (p-1)-fold convolution of the individual PDFs of instantaneous SNRs we derived the overall PDF of the multiple keyhole channel, which was used to derive the expression for average SER of the system. Furthermore, we examined the effect of multiple keyholes on the system performance. Result shows that with the increase of number of keyholes, a significant improvement in the system performance takes place. For a given number of keyholes, by increasing the number of receive antennas further improvement in the system performance is observed.

关键词： Keyhole effect multiple-input multiple-output Nakagami-m distribution Space-time block code Symbol error rate

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Manipulating MIMO Propagation Environment Using Tunable Passive Repeater

Manipulating MIMO Propagation Environment Using Tunable Pass...

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Asia-Pacific Microwave Conference Proceedings

作者： Honma, Naoki Takahashi, Yuta Tsunekawa, Yoshitaka Iwate Univ Ueda Fac Engn Morioka Iwate 0208551 Japan

ISBN: (纸本)9784902339314

A multiple-input-multiple-output (MIMO) channel manipulation using tunable passive repeater is presented in this paper. The passive repeater has multiple antennas and each of them has a phase-shifter function. The MIMO channel capacity is maximized by controlling all elements individually in the passive repeater. The effectiveness of the proposed passive repeater is evaluated numerically and experimentally. From these results, it is found that the MIMO channel capacity can be improved by about 40 % due to the tunability of the passive repeater.

关键词： Passive repeater multiple-input multiple-output capacity

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HPA Nonlinearities Mitigation by Joint Predistorter and Constellation Rotation Using MIMO Communication Systems

HPA Nonlinearities Mitigation by Joint Predistorter and Cons...

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13th Annual Wireless Telecommunications Symposium (WTS)

作者： Jan, Latif Zafar, Mohammad Haseeb Ahmed, Ishtiaq Babar, Mohammad Inayatullah Mahmud, Sahibzada Ali Khan, Gul Muhammad Gilani, Syed Raza Iqra Natl Univ Peshawar Pakistan Univ Engn & Technol Peshawar Pakistan Salman bin Abdul Aziz Univ Al Kharj Saudi Arabia

ISBN: (纸本)9781479912971

Nonlinearities in wireless communication channels foil the performance of the communication systems either at the transmitter or receiver end. This paper explains the concept of the transmitter-side nonlinearities that are induced by the High Power Amplifiers (HPA), the final stage at the transmitter side of the communication system. HPA nonlinearities create in-band and out-of-band distortions in wireless communication systems. The in-band distortion results in the degradation of overall performance of Bit Error Rate (BER) and the capacity of the mobile operations. On the other hand, out-of-band distortion creates the spectral broadening effects that degrade the performance of other operators usually operate in the near bands. This paper presents a novel method for the mitigation of HPA nonlinearities by joint predistorter and constellation rotation in multiple-input multiple-output (MIMO) wireless communication systems. The results reveal that the joint nonlinearity compensation technique in MIMO communications system enhances the overall error rate performance of the system. Furthermore to exploit the benefits of proposed technique;Symbol Error Rate (SER) curves for the MIMO multiplexing and Alamouti Space Time Block Codes (STBC) are presented with improvements in their signal to noise ratio.

关键词： High Power Amplifiers multiple-input multiple-output Symbol Error Rate Space Time Block Codes

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