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Structured compressive sensing-based non-orthogonal time-domain training channel state information acquisition for multiple input multiple output systems

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IET COMMUNICATIONS 2016年第6期10卷 685-690页

作者： Ding, Wenbo Yang, Fang Liu, Sicong Song, Jian Tsinghua Univ Res Inst Informat Technol Beijing 100084 Peoples R China Tsinghua Univ Dept Elect Engn Beijing 100084 Peoples R China Guangdong Prov Shenzhen City Key Lab Digital TV S Shenzhen 518057 Peoples R China

In practical multiple input multiple output (MIMO) systems, accurate knowledge of the channel state information (CSI) is a prerequisite to guarantee the system performance. The conventional CSI acquisition methods for MIMO system usually rely on the orthogonal (either time- or frequency-domain) training sequences (TSs) to estimate the channel associated with each transmit-receive antenna pair, which is not spectrally efficient. This study proposes a non-orthogonal time-domain training-based CSI acquisition approach for MIMO systems under the framework of structured compressive sensing. By exploiting the spatial-temporal correlations of the sparse MIMO channels, a spatially-temporally spARsity-adaptivE-simultaneous orthogonal matching pursuit algorithm is proposed, which could use the inter-block interference free region of very small dimension within the received TS to recover the multiple channels. Furthermore, the proposed algorithm could utilise the priori channel partial common support to improve the recovery probability and reduce the complexity. Simulation results show that the proposed scheme has better performance and higher spectral efficiency than the conventional MIMO schemes, which might be an appealing solution for the future wireless communications.

关键词： Orthogonal spectral efficiency non-orthogonal Channel state information output system System performance CARRIER SYSTEM multiple input multiple output systems

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Current Misuses and Future Prospects for Printed multiple-input, multiple-output Antenna systems

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IEEE ANTENNAS AND PROPAGATION MAGAZINE 2017年第2期59卷 162-170页

作者： Sharawi, Mohammad S. King Fahd Univ Petr & Minerals Elect Engn Dhahran Saudi Arabia Antennas & Microwave Struct Design Lab Dhahran Saudi Arabia

In the past six years or so, the number of scientific articles and conference papers providing possible multiple-input, multiple-output (MIMO) antenna system solutions has noticeably increased. Flagship conferences on antennas and propagation have recently had multiple sessions addressing MIMO antenna systems and their applications. The importance of such antenna systems lies in the magnitude of their application in current wireless devices and gadgets, and this thrust will continue because fourth-generation (4G) and the upcoming fifth-generation (5G) wireless standards rely heavily on MIMO technology. But throughout the years, and up until now, a wide range of publications still suffer from some major misconceptions and unclear understanding of the fundamental aspects while designing, characterizing, and evaluating such multi-antenna systems. In this article, I shine some light on a few of these fundamental issues and try to clarify them. Some examples from the literature are given to show the magnitude of such issues, and the goal is to try to avoid them in all future works. Finally, some prospects for the use of MIMO-based antenna systems in upcoming wireless standards and their enabling technologies are presented.

关键词： ANTENNA SYSTEM gadgets Conference Papers ANTENNA multiple input multiple output systems wide-range wireless device

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Performance evolution of trellis coding in multiple input multiple output communication systems-A review

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JOURNAL OF COMMUNICATIONS TECHNOLOGY AND ELECTRONICS 2014年第11期59卷 1247-1252页

作者： Arunachalaperumal, C. Arun, C. Dhilipkumar, S. Abija, G. SA Engn Coll Chennai Tamil Nadu India RMKCET Madras Tamil Nadu India

In recent years, it has been realized that the multiple input multiple output (MIMO) communication system is inevitable in accelerating the evolution of high data rate applications. Also the latest research in Information and Communication Technology has told that considerable gains in capacity of wireless communication are feasible in MIMO systems. MIMO with Space Time Trellis Code (STTC) offers both diversity gain and coding gain. This paper discusses the evolutional variants of Space Time Trellis Code developed over a decade. The performance of New Trellis code for STTC, STTC for 4-PSK, Space Frequency Trellis code (SFTC), Space Time Bit Trellis Code, and Silver STTC have been studied and discussed. STTC with Trellis Coded Modulation creates a bandwidth efficient system with coding gain.

关键词： Application rates space-time trellis coding multiple input multiple output systems Communication technology Trellis codes coding Diversity methods CARRIER SYSTEM

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Precoding for multiple-input multiple-output systems with space-time block coding over correlated Rician fading channels

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IET COMMUNICATIONS 2014年第2期8卷 163-171页

作者： Yu, Xiang-Bin Dang, Xiao-Yu Yun, Rui Wang, Ying-Guan Wu, Bin-Bin Nanjing Univ Aeronaut & Astronaut Dept Elect Engn Nanjing Jiangsu Peoples R China Southeast Univ Natl Mobile Commun Res Lab Nanjing Jiangsu Peoples R China Chinese Acad Sci Shanghai Adv Res Inst Shanghai Peoples R China Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai Peoples R China

Based on the asymptotic analysis in spatially correlated Rician fading channel, the precoders for space-time block-coded multiple-input multiple-output system at high and low signal-to-noise ratios (SNRs) are, respectively, designed to minimise the system bit error rate (BER). The precoding for high SNR provides closed-form positive power allocation by using the Langrage optimisation method, and has the BER performance close to that of the optimal scheme, especially at high SNR. The Langrage multiplier does exist and is unique, and practical Newton's method is proposed to find its optimal value. Moreover, it has a closed-form solution for some special cases. Thus, it avoids the iterative calculation of some existing precoding schemes. The precoding for low SNR has a closed-form solution similar to onedirectional (1-D) beamforming, and can obtain the performance very close to that of the optimal scheme at low SNR. By combining the above two schemes, a simple and effective suboptimal precoding scheme can be achieved for different SNRs. Simulation results show that the proposed scheme derived from the integration of high and low SNR can provide BER lower than the equal power precoding, and obtain the BER performance close to that of the existing optimal scheme with low complexity.

关键词： Scheme prediction coding bit error rate performance output system multiple input multiple output systems space time block coding Newton method Block codes Rician fading channels low SNR iterative calculation high SNR

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Lattice-reduction-aided semidefinite relaxation detection algorithms for multiple-input multiple-output systems

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IET COMMUNICATIONS 2014年第4期8卷 448-454页

作者： Shao, Zi Yun Cheung, Sing Wai Yuk, Tung Ip Guangzhou Univ Sch Mech & Elect Engn Guangzhou Higher Educ Mega Ctr Guangzhou Guangdong Peoples R China Univ Hong Kong Dept Elect & Elect Engn Hong Kong Hong Kong Peoples R China

multiple-input multiple-output (MIMO) system is considered to be one of the key technologies of long-term evolution, since it achieves requirements of high throughput and spectral efficiency. The semidefinite relaxation (SDR) detection for MIMO systems is an attractive alternative to the optimum maximum likelihood (ML) decoding because it is very computationally efficient. In the case of the binary phase shift keying and four quadrature amplitude modulation constellations, the block error rate (BLER) performance of SDR detection is fairly close to the optimum BLER performance. However, for high-order modulation systems, their BLER performance is still unsatisfactory compared with the ML decoding. Lattice reduction technology can transform a matrix into a new equivalent one with more orthogonal and shorter basis vectors. It has been combined with linear decoders to improve their BLER performance. Inspired by this, the authors proposed two lattice-reduction-aided MIMO detection algorithms based on SDR. Simulation results demonstrate that they can provide near-optimum BLER performance with polynomial time complexity.

关键词： error statistics MIMO communication MIMO systems quadrature amplitude modulation Long Term Evolution polynomial time complexity lattice reduction aided MIMO detection algorithms linear decoders lattice reduction technology high order modulation systems optimum BLER performance block error rate quadrature amplitude modulation constellations binary phase shift keying optimum maximum likelihood decoding SDR detection spectral efficiency long term evolution MIMO system multiple input multiple output systems lattice reduction aided semidefinite relaxation detection algorithms

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An evaluation of the influence of Eigensystem Realization Algorithm settings on multiple input multiple output system identification

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JOURNAL OF VIBRATION AND CONTROL 2022年第21-22期28卷 3286-3301页

作者： Soares Jr, Dirceu Serpa, Alberto Luiz Univ Estadual Campinas UNICAMP Campinas Brazil Fed Inst Espirito Santo IFES Vitoria Spain

One characteristic of the Eigensystem Realization Algorithm method for system identification concerns about the difficulty of finding more appropriate parameters to run the algorithm. One of this work's purposes is to tackle the cumbersome task of achieving the ideal algorithm settings, providing additional knowledge about algorithm parameters' influence, and searching to improve results with quicker settings of the algorithm's parameters, especially for multiple input multiple output (MIMO) systems. The application of a Fit Rate indicator to evaluate the identified system arises as a novelty in the Eigensystem Realization Algorithm applications, aiming to assess the system identification performance and drive the algorithm to better adjustments. Another objective of this article regards the application of a Pseudo Random Binary Sequence as excitation signals, which has not been used until now with the Eigensystem Realization Algorithm, despite being successfully applied in the system identification process. The proposed approach is verified and analyzed with numerical simulations for a mass-spring-damper model of 5 degrees of freedom. The results reported in time response analysis and frequency response analysis allow us to realize the effect of settings accordingly for the system identification improvement. The results analysis was extended to simulate and compare the Pseudo Random Binary Sequence with Gaussian white noise excitation, and the system was also submitted to the presence of measurement noise.

关键词： System identification Eigensystem Realization Algorithm multiple input multiple output systems Pseudo Random Binary Sequence Hankel matrix

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Massive MIMO uplink and downlink joint representation based on couple dictionary learning

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IET COMMUNICATIONS 2024年第19期18卷 1551-1563页

作者： Guan, Qing Yang Xian Int Univ Coll Engn Xian 710070 Peoples R China

The challenge of jointly representing both the uplink (UL) and downlink (DL) in massive multiple input multiple output (MIMO) systems have been tackled. Considering the angular reciprocity, a couple dictionary learning (CDL) support to enhance performance and address high complexity has been introduced. This approach minimizes the number of pilots and improves accuracy. Currently, accuracy analysis of UL/DL representation primarily relies on simulation. To bridge this gap, a proportion factor (PF) operator is proposed for CDL to assess accuracy. Specifically, a qualitative analysis formula is provided for accuracy and an optimal upper bound is established. Through theoretical proof, it is demonstrated that the accuracy of CDL for representation is mainly influenced by the cross-correlation between the pilot matrix and the dictionary matrix. Inspired by PF operator, an optimal couple dictionary learning (OCDL) algorithm using singular value decomposition (SVD) is introduced to obtain dictionary updating, aiming at high-precision representation. By establishing normalized mean squared error (NMSE), successful representation ratio, bit error rate (BER), and constellation performance, an OCDL algorithm that outperforms existing methods is showcased and channel representation accuracy is enhanced significantly. We propose a proportion factor operator for couple dictionary learning to assess accuracy. Inspired by PF operator, we introduce an optimal couple dictionary learning algorithm using singular value decomposition to obtain dictionary updating, aiming at high-precision representation. image

关键词： 5G mobile communication multiple input multiple output systems signal processing signal representation

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Sparse representation for massive MIMO satellite channel based on joint dictionary learning

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ELECTRONICS LETTERS 2024年第17期60卷

作者： Guan, Qing yang Wu, Shuang Xian Int Univ Coll Engn Xian 710070 Peoples R China

A constrained joint dictionary learning (CJDL) algorithm for high-precision channel representation in massive multiple input multiple output (MIMO) satellite systems is proposed. Furthermore, taking into account the angular reciprocity of massive MIMO satellite systems, joint dictionary learning can establish a common support basis for both uplink and downlink. Previous deterministic dictionary has utilized deterministic basis, such as discrete Fourier transform (DFT) or orthogonal DFT (ODFT) basis, which tend to represent noise interference as part of channel characteristics. Furthermore, this deterministic dictionary is not able to adapt to dynamic communication environments. However, dictionary learning has shown the potential to significantly improve the accuracy of channel representation. Nevertheless, current research on training dictionary lacks analysis regarding constraints and boundary requirements, resulting in a suboptimal basis. To address this issue, conditional constraints associated with joint dictionary for channel representation are analysed. To screen for optimal basis, the joint dictionary is subject to constraints, including uplink and downlink constraints. Furthermore, the authors aim to quantify the maximum boundary of joint dictionary learning. Additionally, a joint dictionary updating method with singular value decomposition under constraint boundary conditions is proposed. Simulation results demonstrate that the proposed CJDL algorithm provides a more accurate and robust channel representation. Current research on training dictionary lacks analysis regarding constraints and boundary requirements, resulting in a suboptimal basis. To address this issue, conditional constraints associated with joint dictionary for channel representation are analysed. A constrained joint dictionary learning algorithm for high-precision channel representation in massive multiple input multiple output satellite systems is also proposed. image

关键词： 5G mobile communication multiple input multiple output systems

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A two element EBG-inspired UWB MIMO antenna with triple band notched characteristics and high isolation

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SADHANA-ACADEMY PROCEEDINGS IN ENGINEERING SCIENCES 2023年第1期48卷 1-16页

作者： Kapure, Vijay R. Rathod, Surendra S. Sardar Patel Inst Technol Dept Elect Engn Mumbai 400058 India Fr Conceicao Rodrigues Coll Engn Dept Elect & Comp Sci Engn Mumbai 400050 India

In this paper, an EBG-inspired two element triple band-notched ultra wideband multi input multi output antenna is proposed. The antenna is fabricated with the overall size of 47x38x0.8 mm(3) using low cost FR-4 epoxy substrate. Designing and simulation is carried out using Ansys HFSS software. Using single EBG structure, triple band notches at 3.3, 5.72 and 8.32 GHz are obtained satisfying WIMAX, WLAN and uplink satellite X-bands respectively. By inserting inverted L-shaped stubs on the ground plane, an improved isolation better than 25 dB is achieved throughout the UWB range. Surface current distribution and radiation pattern of proposed MIMO antenna in E-plane and H-plane are studied and discussed. Performance parameters such as ECC, DG, CCL, TARC and MEG are also investigated and found to be within the acceptable limits specified for diversity applications. Therefore UWB-MIMO applications wherein triple band-notched MIMO antenna with simplified design, compact size and improved isolation is desired, proposed MIMO antenna will out stand as strong candidature.

关键词： Electromagnetic band gap structure multiple input multiple output systems ultra wide band diversity antenna

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Low pilot overhead channel estimation for CP-OFDM-based massive MIMO OTFS system

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IET COMMUNICATIONS 2022年第10期16卷 1071-1082页

作者： Li, Tong Han, Chuang Yao, Rugui Fan, Ye Zuo, Xiaoya Northwestern Polytech Univ Sch Elect & Informat Xian Peoples R China

In high-speed mobile scenarios, due to the high-speed relative motion between transmitter and receiver, the high Doppler frequency shift interferes with the inter-subcarrier orthogonality in orthogonal frequency-division multiplexing (OFDM) systems. Therefore its performance is significantly degraded. Recently, orthogonal time-frequency space (OTFS) is considered as an effective alternative scheme to OFDM for time-varying channels. As with OFDM-massive multiple input multiple output (MIMO) systems, downlink channel estimation is necessary for OTFS-massive MIMO systems to improve the spectral efficiency in frequency-division duplex (FDD) mode without channel reciprocity. Here, first the cyclic prefix -OFDM-based massive MIMO OTFS system channel with antenna directivity pattern is analyzed, and transform the burst sparsity in the angle domain into block sparsity by using non-uniform Fourier transform (NUFT). Furthermore, to solve the problem that the pilot overhead grows linearly with the number of antennas, we propose a three-dimensional (3D) dynamic support detect (DSD) algorithm. Compared with the traditional OMP algorithm, and the 3D-structured orthogonal matching pursuit algorithm, simulation results demonstrate the proposed DSD algorithm has higher channel estimation accuracy, and lower pilot overhead.

关键词： frequency-division duplex mode orthogonal frequency-division multiplexing systems channel reciprocity OTFS-massive MIMO systems MIMO communication time-frequency analysis high-speed relative motion radio transceivers downlink channel estimation channel estimation massive MIMO OTFS system channel inter-subcarrier orthogonality multiple input multiple output systems OFDM-massive CP-OFDM-based massive MIMO OTFS system time-varying channels orthogonal matching pursuit algorithm Fourier transforms orthogonal time-frequency space iterative methods higher channel estimation accuracy OFDM modulation high Doppler frequency shift antenna radiation patterns mobile scenarios low pilot overhead channel estimation antenna arrays

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