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作者： Chang He University of Surrey

学位级别：博士

Regarded as one of the most promising transmission techniques for future wire- less communications, the discrete cosine transform based multicarrier modulation (DCT-MCM) system hold several inherited advantages over the discrete Fourier transform (DFT) based one (DFT-MCM). However, various technical challenges that hinder practical use of DCT-MCM need to be addressed, e. g., enhanced transceiver design and extensions into several important 5th Generation (5G) communication scenarios. The overall objective of the proposed research is to investigate some of the key practical challenges and optimise the receiver im- plementation of general DCT-MCM systems, by which effective solutions are proposed for different future wireless communication scenarios. First, an optimised transmitter structure for the pre-filtering based DCT-MCM system is established to improve the overall system performance. We therefore analyse the pre-filtering effect and investigate the output signal-to-noise ratio (SNR) gain among all subcarriers. Based on the derived instantaneous output SNR expression, the minimum-mean-square-error (MMSE) and maximum like- lihood (ML) detections are re-designed to effectively compensate the coloured noise effect after pre-filtering at the receiver. Second, we give the system model and performance analysis for the pre-filtering based DCT-MCM system in the presence of transceiver imperfections. In par- ticular, an analytical expression in terms of desired signal, ICI and inter-symbol interference (ISI) is presented by considering carrier frequency offset (CFO), tim- ing offset (TO) and insufficient guard sequence between symbols. In order to compensate for these imperfections, an advanced technique called zero forcing based (ZF-based) iterative channel detection algorithms are proposed to provide significant gain compared with conventional detection methods in terms of BER performance. Third, in order to render the DCT-MCM applicable to multiple-input multiple- out

关键词： DCT-MCM effective detections index modulation multiple-input multiple-output imperfections performance analysis

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Coding for relay networks with parallel Gaussian channels

Coding for relay networks with parallel Gaussian channels

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作者： Huang, Yu-Chih Texas A&M University

学位级别：Ph.D.

A wireless relay network consists of multiple source nodes, multiple destination nodes, and possibly many relay nodes in between to facilitate its transmission. It is clear that the performance of such networks highly depends on information forwarding strategies adopted at the relay nodes. This dissertation studies a particular information forwarding strategy called compute-and-forward. Compute-and-forward is a novel paradigm that tries to incorporate the idea of network coding within the physical layer and hence is often referred to as physical layer network coding. The main idea is to exploit the superposition nature of the wireless medium to directly compute or decode functions of transmitted signals at intermediate relays in a network. Thus, the coding performed at the physical layer serves the purpose of error correction as well as permits recovery of functions of transmitted signals. For the bidirectional relaying problem with Gaussian channels, it has been shown by Wilson et al. and Nam et al. that the compute-and-forward paradigm is asymptotically optimal and achieves the capacity region to within 1 bit; however, similar results beyond the memoryless case are still lacking. This is mainly because channels with memory would destroy the lattice structure that is most crucial for the compute-and-forward paradigm. Hence, how to extend compute-and-forward to such channels has been a challenging issue. This motivates this study of the extension of compute-and-forward to channels with memory, such as inter-symbol interference. The bidirectional relaying problem with parallel Gaussian channels is also studied, which is a relevant model for the Gaussian bidirectional channel with inter-symbol interference and that with multiple-input multiple-output channels. Motivated by the recent success of linear finite-field deterministic model, we first investigate the corresponding deterministic parallel bidirectional relay channel and fully characterize its capacity region. T

关键词： Network information theory wireless relay networks bidirectional relay channels inter-symbol interference multiple-input multiple-output compute-and-forward Thesis

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Millimeter-Wave Full-Duplex MIMO Systems with Hybrid Beamforming

Millimeter-Wave Full-Duplex MIMO Systems with Hybrid Beamfor...

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10th International Conference on Communication Software and Networks (ICCSN)

作者： Wei, Feng-Cheng Ku, Meng-Lin Chung, Char-Dir Natl Taiwan Univ Grad Inst Commun Engn Taipei Taiwan Natl Cent Univ Dept Commun Engn Taoyuan Taiwan

ISBN: (纸本)9781538672242

In this paper, we investigate a millimeter-wave fullduplex (FD) multiple-input multiple-output system, where an FD base station is capable of concurrently receiving data from a half-duplex (HD) uplink user and transmitting data to an HD downlink user via hybrid beamforming. To effectively mitigate the self-interference and co-channel interference, the sum rate of the uplink and downlink transmissions is maximized by jointly designing hybrid beamforming at the base station and digital beamforming at the two users. The design problem is non-convex due to the multiplication among beamforming matrices, and it is converted to an equivalent weighted sum minimum mean square error ( WMMSE) problem for mathematical tractability. An iterative WMMSE hybrid beamforming algorithm is first proposed based on alternative optimization. By adding semi-unitary structures to digital beamforming, a low-complexity semi-unitary hybrid beamforming algorithm is developed without requiring iterations. Computer simulations are used to demonstrate the effectiveness of the proposed systems, as compared with conventional HD systems.

关键词： full duplex millimeter wave self-interference hybrid beamforming multiple-input multiple-output

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Performance Comparison of Deep Learning Based Signal Detection and SIC in MIMO - NOMA for 5G Enabled Vehicular Communication 15

Performance Comparison of Deep Learning Based Signal Detecti...

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15th International Conference on Computing Communication and Networking Technologies, ICCCNT 2024

作者： Beena, A.O. Sameer, S.M. Dept. of Electronics Engineering Kottayam India National Institute of Technology Calicut Dept. of Electronics & Communication Engineering Calicut India

ISBN: (纸本)9798350370249

An investigation on the performance of a proposed deep learning (DL)-based signal detection scheme over the traditional successive interference cancellation (SIC) method for multiple-input multiple-output (MIMO) - non-orthogonal multiple access (NOMA) based downlink system for vehicular communication is presented. The proposed scheme is analyzed for a system of two users in a cell experiencing selective frequency Rayleigh fading channels. The DL-based MIMO-NOMA receiver detects signals in a single-step process without explicitly estimating channel state information. The long short-term memory (LSTM) based scheme is proposed to perform joint channel estimation and signal detection. The performance of the proposed DL based detection scheme is compared with the traditional method SIC based on least square (LS) estimation and minimum mean square error (MMSE) estimation. The simulation results show that the proposed DL-based detection is more effective than conventional SIC techniques. Also, it shows better adaptability to variations in cyclic prefix (CP) length and the number of pilot symbols in the frame. It has been observed that even in cases of severe inter-symbol interference (ISI), the proposed DL-based method outperforms the LS and MMSE based conventional SIC detectors. © 2024 IEEE.

关键词： 5G Channel state information Deep Learning Downlink Long Short Term Memory multiple-input multiple-output Non-orthogonal multiple access Successive Interference Cancellation Vehicular communication

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Degrees of freedom of wireless interference network

Degrees of freedom of wireless interference network

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作者： Ke, Lei Iowa State University

学位级别：Ph.D.

Wireless communication systems are different from the wired systems mainly in three aspects: fading, broadcast, and superposition. Wireless communication networks, and multi-user communication networks in general, have not been well understood from the information-theoretic perspective: the capacity limits of many multi-user networks are not known. For example, the capacity region of a two-user single-antenna interference channel is still not known, though recent result can bound the region up to a constant value. Characterizing the capacity limits of multi-user multiple-input multiple-output (MIMO) interference network is usually even more difficult than the single antenna setup. To alleviate the difficulty in studying such networks, the concept of degrees of freedom (DoF) has been adopted, which captures the first order behavior of the capacities or capacity regions. One important technique developed recently for quantifying the DoF of multi-user networks is the so-called interference alignment. The purpose of interference alignment is to design the transmit signals structurally so that the interference signals from multiple interferers are aligned to reduce the signal dimensions occupied by interference. In this thesis, we mainly study two problems related to DoF and interference alignment: (1) DoF region of MIMO full interference channel (FIC) and Z interference channel (ZIC) with reconfigurable antennas, and (2) the DoF region of an interference network with general message demands. For the first problem, we derive the outer bound on the DoF region and show that it is achievable via time-sharing or beamforming except for one special case. As to this particular special case, we develop a systematic way of constructing the DoF-achieving nulling and beamforming matrices. Our results reveal the potential benefit of using the reconfigurable antenna in MIMO FIC and ZIC. In addition, the achievability scheme has an interesting space-frequency interpretation. For the s

关键词： degrees of freedom information theory interference alignment interference channel multiple-input multiple-output wireless communications

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BER Analysis for a MIMO-NOMA System Using QPSK Modulation and Linear MMSE Detection

BER Analysis for a MIMO-NOMA System Using QPSK Modulation an...

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2023 IEEE Globecom Workshops, GC Wkshps 2023

作者： Wang, Chin-Liang Ding, Yu-Cheng National Tsing Hua University Dept. of Elect. Eng. and Inst. of Commun. Eng. Hsinchu Taiwan Institute of Communications Engineering National Tsing Hua University Hsinchu Taiwan

ISBN: (纸本)9798350370218

In this paper, the bit error rate (BER) performance is investigated for a two-user downlink multiple-input multiple-output (MIMO) non-orthogonal multiple access (NOMA) system that employs quadrature phase shift keying (QPSK) modulation and linear minimum mean-squared error (MMSE) detection for each user's signal. In addition to error propagation from successive interference cancellation considered by existing related works for single-input single-output NOMA systems, multiple access interference is taken into account for MIMO-NOMA transmission. Exact BER expressions are derived for both users under the availability of perfect channel state information. Computer simulation results are given to verify the accuracy of the derived BER expressions. © 2023 IEEE.

关键词： Bit error rate minimum mean-squared error multiple access interference multiple-input multiple-output non-orthogonal multiple access quadrature phase shift keying successive interference cancellation

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Interference Leakage Minimization in RIS-Assisted MIMO Interference Channels 48

Interference Leakage Minimization in RIS-Assisted MIMO Inter...

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48th IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP 2023

作者： Santamaria, Ignacio Soleymani, Mohammad Jorswieck, Eduard Gutiérrez, Jesús Universidad de Cantabria Department of Communications Engineering Santander39005 Spain Universität Paderborn Signal and System Theory Group Paderborn33098 Germany Technische Universität Braunschweig Institute for Communications Technology Braunschweig38106 Germany 15236 Germany

ISBN: (纸本)9781728163277

We address the problem of interference leakage (IL) minimization in the K-user multiple-input multiple-output (MIMO) interference channel (IC) assisted by a reconfigurable intelligent surface (RIS). We describe an iterative algorithm based on block coordinate descent to minimize the IL cost function. A reformulation of the problem provides a geometric interpretation and shows interesting connections with envelope precoding and phase-only zero-forcing beamforming problems. As a result of this analysis, we derive a set of necessary (but not sufficient) conditions for a phase-optimized RIS to be able to perfectly cancel the interference on the K-user MIMO IC. © 2023 IEEE.

关键词： interference channel interference leakage minimization multiple-input multiple-output Reconfigurable intelligent surface (RIS)

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Decision Feedback Channel Estimation for Integrated Mobile VLCP Based on STBC-MIMO

Decision Feedback Channel Estimation for Integrated Mobile V...

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2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings, ACP/POEM 2023

作者： Sun, Yuzhe You, Xiaodi Chen, Jian Yu, Changyuan Gao, Mingyi Shen, Gangxiang School of Electronic and Information Engineering Soochow University Suzhou China School of Telecommunications and Information Engineerine Nanjing University of Posts and Telecommunications Nanjing China The Hong Kong Polytechnic University Department of Electronic and Information Engineering Hong Kong

Decision feedback channel estimation is employed to enhance the performance of an integrated mobile VLCP system based on STBC-MIMO, where reliable communication and positioning can simultaneously be achieved when rece... 详细信息

ISBN: (纸本)9798350312614

关键词： decision feedback channel estimation multiple-input multiple-output space-time block coding visible light communication visible light positioning

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Hybrid Beamforming-based Beam Tracking using Angular speed in Massive MIMO Systems 14

Hybrid Beamforming-based Beam Tracking using Angular speed i...

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14th International Conference on Information and Communication Technology Convergence, ICTC 2023

作者： Sin, Seungseok Cho, Jihun Liu, Huaping Moon, Sangmi Sim, Yuna Kim, Kyunam Kim, Jihyung Hwang, Intae Chonnam National University Deptartment of Ict Convergences System Engineering Gwangju Korea Republic of Oregon State University United States Korea Nazarene University Department of It Artificial Intelligence Cheonan Korea Republic of Alps Electric Korea Co. Ltd Gwangju Korea Republic of Electronics and Telecommunications Research Institute Spatial Wireless Transmission Research Section Daejeon Korea Republic of Chonnam National University Department of Electronic Engineering and Department of Ict Convergence System Engineering Gwangju Korea Republic of

ISBN: (纸本)9798350313277

This paper proposes an angular speed 3D-based beam tracking method using hybrid beamforming. We propose a new beam tracking algorithm that enables dynamic pilot insertion based on closed loop feedback control by utilizing the Line of Sight (LoS) path of the channel between T-BS and UAV-UE. Simulations show that the proposed beam tracking method has improved overall performance in terms of beamforming gain and spectral efficiency (SE). © 2023 IEEE.

关键词： 3D beam tracking hybrid beamforming multiple-input multiple-output orthogonal frequency division multiplexing

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Mutual coupling reduction of multiple antenna systems

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Frontiers of Information Technology & Electronic Engineering 2020年第3期21卷 366-377页

作者： Jia-yin GUO Feng LIU Guo-dong JING Lu-yu ZHAO Ying-zeng YIN Guan-long HUANG Key Laboratory of Antennas and Microwave Technologies Xidian UniversityXi’an 710071China Guangdong Provincial Mobile Terminal Microwave and Millimeter-Wave Antenna Engineering Research Center College of Information EngineeringShenzhen UniversityShenzhen 518060China

A multi-band multi-antenna system has become an important trend in the development of mobile communication ***,strong mutual coupling tends to occur between antenna elements with a small space,distorting array antennas’***,in the multiple-input multiple-output(MIMO)antenna system,high isolation based on miniaturization of the antenna array has been *** study in depth the methods of decoupling between antenna *** for the existence of mutual coupling and advantages of mutual coupling reduction are *** the decoupling methods proposed in recent works are compared and ***,we propose a metasurface consisting of double-layer short wires,which can be applied to improve the port isolation of antennas arranged along the H-plane and *** show that the proposed metasurface has good decoupling effect on a closely placed antenna array.

关键词： Mutual coupling multiple-input multiple-output Antenna array Metasurface Decoupling

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