Статті в журналах: "Wireless MIMO Communications"

1

Dr.Raad.H., Thaher. "Environmental Analysis of MIMO Channel Capacity Under Variable." مجلة جامعة الملكة أروى العلمية المحكمة 1, no. 7 (December 30, 2011): 24. http://dx.doi.org/10.58963/qausrj.v1i7.45.

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Digital communication using MIMO has been one of the most promising research areas in wireless communictions nowadays as it offers a lot of promises for future wireless communications .MIMO seems to be the only technology that is advancing the wireless industry from 3Gto 4G systems .I n this work MIMO system has been studied in great detail and simulated for different cases and it was concentrated on the performance of its capacity under several environmental conditions . MIMO system offer significant gains in performance over traditional wireless communication systems . Spatial multiplexing increases system throughput without consuming frquency spectrum and spatial diversity make the link more robust .MIMO system was described was described and simulation results were presented and discussed. Multiple antenna techniques are a key to boosting the performance of modern wireless systems.Key words: MIMO, spatial multiplexing, capacity, diversity,SNR

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2

Stuber, G. L., J. R. Barry, S. W. McLaughlin, Ye Li, M. A. Ingram, and T. G. Pratt. "Broadband MIMO-OFDM wireless communications." Proceedings of the IEEE 92, no. 2 (February 2004): 271–94. http://dx.doi.org/10.1109/jproc.2003.821912.

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3

Haykin, S., M. Sellathurai, Y. de Jong, and T. Willink. "Turbo-MIMO for wireless communications." IEEE Communications Magazine 42, no. 10 (October 2004): 48–53. http://dx.doi.org/10.1109/mcom.2004.1341260.

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4

Sejan, Mohammad Abrar Shakil, Md Habibur Rahman, Md Abdul Aziz, Dong-Sun Kim, Young-Hwan You, and Hyoung-Kyu Song. "A Comprehensive Survey on MIMO Visible Light Communication: Current Research, Machine Learning and Future Trends." Sensors 23, no. 2 (January 9, 2023): 739. http://dx.doi.org/10.3390/s23020739.

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Visible light communication (VLC) has contributed new unused spectrum in addition to the traditional radio frequency communication and can play a significant role in wireless communication. The adaptation of VLC technology enhances wireless connectivity both in indoor and outdoor environments. Multiple-input multiple-output (MIMO) communication has been an efficient technique for increasing wireless communications system capacity and performance. With the advantages of MIMO techniques, VLC can achieve an additional degree of freedom. In this paper, we systematically perform a survey of the existing work based on MIMO VLC. We categorize the types of different MIMO techniques, and a brief description is given. Different problem-solving approaches are given in the subsequent sections. In addition, machine learning approaches are also discussed in sufficient detail. Finally, we identify the future study direction for MIMO-based communication in VLC.

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5

Nguyen, Hoang, Johnson I. Agbinya, and John Devlin. "Channel Characterisation and Link Budget of MIMO Configuration in Near Field Magnetic Communication." International Journal of Electronics and Telecommunications 59, no. 3 (September 1, 2013): 255–62. http://dx.doi.org/10.2478/eletel-2013-0030.

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Abstract Traditional radio communication has gained significantly from using multiple input and multiple output (MIMO) architecture in the system. Many wireless applications, such as wireless LAN and cellular network, have adopted this technology to improve their system performance. However, the effect of MIMO systems has not been investigated in the case of inductive near field short range communications. The purpose of this paper is to explore a new method for increasing the magnetic communication range using MIMO. Three system models includingMISO, SIMO and MIMO are proposed to characterize the number of transmitters and receivers to the link. These models have helped to extend not only the range but also the communication channel in NFMIC.

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6

Sun, Y. "Editorial: MIMO wireless and mobile communications." IEE Proceedings - Communications 153, no. 4 (2006): 475. http://dx.doi.org/10.1049/ip-com:20069019.

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7

Gu, X., X. H. Peng, and G. C. Zhang. "MIMO systems for broadband wireless communications." BT Technology Journal 24, no. 2 (April 2006): 90–96. http://dx.doi.org/10.1007/s10550-006-0044-7.

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8

Bhatt, Maharshi K., Bhavin S. Sedani, and Komal Borisagar. "Performance analysis of massive multiple input multiple output for high speed railway." International Journal of Electrical and Computer Engineering (IJECE) 11, no. 6 (December 1, 2021): 5180. http://dx.doi.org/10.11591/ijece.v11i6.pp5180-5188.

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This paper analytically reviews the performance of massive multiple input multiple output (MIMO) system for communication in highly mobility scenarios like high speed Railways. As popularity of high speed train increasing day by day, high data rate wireless communication system for high speed train is extremely required. 5G wireless communication systems must be designed to meet the requirement of high speed broadband services at speed of around 500 km/h, which is the expected speed achievable by HSR systems, at a data rate of 180 Mbps or higher. Significant challenges of high mobility communications are fast time-varying fading, channel estimation errors, doppler diversity, carrier frequency offset, inter carrier interference, high penetration loss and fast and frequent handovers. Therefore, crucial requirement to design high mobility communication channel models or systems prevails. Recently, massive MIMO techniques have been proposed to significantly improve the performance of wireless networks for upcoming 5G technology. Massive MIMO provide high throughput and high energy efficiency in wireless communication channel. In this paper, key findings, challenges and requirements to provide high speed wireless communication onboard the high speed train is pointed out after thorough literature review. In last, future research scope to bridge the research gap by designing efficient channel model by using massive MIMO and other optimization method is mentioned.

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9

Wang, Qian, Ning Mu, LingLi Wang, Safieddin Safavi-Naeini, and JingPing Liu. "5G MIMO Conformal Microstrip Antenna Design." Wireless Communications and Mobile Computing 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/7616825.

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With the development of wireless communication technology, 5G will develop into a new generation of wireless mobile communication systems. MIMO (multiple-input multiple-output) technology is expected to be one of the key technologies in the field of 5G wireless communications. In this paper, 4 pairs of microstrip MIMO conformal antennas of 35 GHz have been designed. Eight-element microstrip Taylor antenna array with series-feeding not only achieves the deviation of the main lobe of the pattern but also increases the bandwidth of the antenna array and reduces sidelobe. MIMO antennas have been fabricated and measured. Measurement results match the simulation results well. The return loss of the antenna at 35 GHz is better than 20 dB, the first sidelobe level is −16 dB, and the angle between the main lobe and the plane of array is 60°.

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10

Saini, Mehak, and Surender K. Grewal. "Transmit Antenna Selection Methods For Mimo Systems In Wireless Communications." Journal of University of Shanghai for Science and Technology 23, no. 08 (August 16, 2021): 523–31. http://dx.doi.org/10.51201/jusst/21/08424.

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Though MIMO systems improve performance of a wireless communication network by the usage of multiple antennas, demand of distinct set of RF chain (i.e., electronic components required for antenna transmission and reception, in wireless communication) for all the antennas leads to an increase in complexity and cost. Antenna selection technique of MIMO has proved to be a good means to solve this issue. Antenna Selection methods find optimal number of antennas required out of the total antennas present in the MIMO (Multiple Input Multiple Output) system. The selection of antenna can be performed at both ends of the communication network i.e., transmitter or receiver. In this paper, an overview of various Transmit Antenna Selection techniques for various MIMO systems is presented.

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11

Abouda, A. A., and N. G. Tarhuni. "MIMO Channel Gain Mechanisms Relative to SISO Channel." Journal of Engineering Research [TJER] 7, no. 2 (December 1, 2010): 40. http://dx.doi.org/10.24200/tjer.vol7iss2pp40-47.

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In contrast to the rest of wireless communication technologies, multiple-input multiple-output (MIMO) technology enjoys different gain mechanisms that make it very attractive for reliable high data rate wireless communications. This paper presents a study on these gain mechanisms with particular emphasis on the case of high average received signal to noise ratio (SNR) where the MIMO system deployment is most promising. We write the MIMO channel capacity in terms of gains relative to a single- input single-output (SISO) wireless channel. Doing so, spatial multiplexing gain and power gain of MIMO wireless channels become more insightful. Based on this analysis a switching scheme between spatial multiplexing and transmit diversity is proposed. We support our discussion with numerical results which show that under a high data rate spatial multiplexing scheme the contribution of each gain mechanism to the total channel capacity depends on the channel Ricean factor, the average received SNR, and the MIMO system size. The proposed switching scheme gives about 2 dB gain in bit error rate performance relative to the spatial multiplexing mode.

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12

Behna, Shuja, and Neetu Sikarwar. "MIMO-OFDMs BER and Design Performance for Wireless Broadband Communications." International Journal of Trend in Scientific Research and Development Volume-2, Issue-3 (April 30, 2018): 4–7. http://dx.doi.org/10.31142/ijtsrd10768.

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13

Chae, Chan-Byoun, Antonio Forenza, Robert Heath, Matthew McKay, and Iain Collings. "Adaptive MIMO transmission techniques for broadband wireless communication systems [Topics in Wireless Communications." IEEE Communications Magazine 48, no. 5 (May 2010): 112–18. http://dx.doi.org/10.1109/mcom.2010.5458371.

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14

Bhandari, Renuka, and Sangeeta Jadhav. "Spectral Efficient Blind Channel Estimation Technique for MIMO-OFDM Communications." International Journal of Advances in Applied Sciences 7, no. 3 (August 1, 2018): 286. http://dx.doi.org/10.11591/ijaas.v7.i3.pp286-297.

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With emerge of increasing research in the domain of future wireless communications, massive MIMO (multiple inputs multiple outputs) attracted most of researchers interests. Massive MIMO is high-speed wireless communication standards. A channel estimation technology plays the essential role in the MIMO systems. Efficient channel estimation leads to spectral efficient wireless communications. The critics of Inter-Symbol Interference (ISI) are the challenging tasks while designing the channel estimation methods. To mitigate the challenges of ISI, we proposed the novel blind channel estimation method which based on Independent component analysis (ICA) in this paper. Proposed channel estimation it works for both blind interference cancellation and ISI cancellation. The proposed Hybrid ICA (HICA) method depends on pulse shape filtering and ambiguity removal to improve the spectral efficiency and reliability for MIMO communications. The Kurtosis operation is used to measure the complex data at first to estimate the common signals. Then we exploited the advantages of 3rd and 4th order Higher Order Statistics (HOS) to priorities the common signals during the channel estimation. In this paper, we present the detailed design and evaluation of HICA blind channel estimation method. We showed the simulation results of HICA against the state-of-art techniques for channel estimation using BER, MSE, and PAPR.

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15

Huo, Yiming, Xingqin Lin, Boya Di, Hongliang Zhang, Francisco Javier Lorca Hernando, Ahmet Serdar Tan, Shahid Mumtaz, Özlem Tuğfe Demir, and Kun Chen-Hu. "Technology Trends for Massive MIMO towards 6G." Sensors 23, no. 13 (June 30, 2023): 6062. http://dx.doi.org/10.3390/s23136062.

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At the dawn of the next-generation wireless systems and networks, massive multiple-input multiple-output (MIMO) in combination with leading-edge technologies, methodologies, and architectures are poised to be a cornerstone technology. Capitalizing on its successful integration and scalability within 5G and beyond, massive MIMO has proven its merits and adaptability. Notably, a series of evolutionary advancements and revolutionary trends have begun to materialize in recent years, envisioned to redefine the landscape of future 6G wireless systems and networks. In particular, the capabilities and performance of future massive MIMO systems will be amplified through the incorporation of cutting-edge technologies, structures, and strategies. These include intelligent omni-surfaces (IOSs)/intelligent reflecting surfaces (IRSs), artificial intelligence (AI), Terahertz (THz) communications, and cell-free architectures. In addition, an array of diverse applications built on the foundation of massive MIMO will continue to proliferate and thrive. These encompass wireless localization and sensing, vehicular communications, non-terrestrial communications, remote sensing, and inter-planetary communications, among others.

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16

Madeira, João, João Guerreiro, Rui Dinis, Paulo Montezuma, and Luís Miguel Campos. "On the Physical Layer Security Characteristics for MIMO-SVD Techniques for SC-FDE Schemes." Sensors 19, no. 21 (November 1, 2019): 4757. http://dx.doi.org/10.3390/s19214757.

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Multi-Input, Multi-Output (MIMO) techniques are seeing widespread usage in wireless communication systems due to their large capacity gains. On the other hand, security is a concern of any wireless system, which can make schemes that implement physical layer security key in assuring secure communications. In this paper, we study the physical layer security issues of MIMO with Singular Value Decomposition (SVD) schemes, employed along with Single-Carrier with Frequency-Domain Equalization (SC-FDE) techniques. More concretely. the security potential against an unintended eavesdropper is analysed, and it is shown that the higher the distance between the eavesdropper and the transmitter or receiver, the higher the secrecy rate. In addition, in a scenario where there is Line of Sight (LOS) between all users, it is shown that the secrecy rate can be even higher than in the previous scenario. Therefore, MIMO-SVD schemes combined with SC-FDE can be an efficient option for highly secure MIMO communications.

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17

Gursoy, Mustafa Cenk. "MIMO Wireless Communications Under Statistical Queueing Constraints." IEEE Transactions on Information Theory 57, no. 9 (September 2011): 5897–917. http://dx.doi.org/10.1109/tit.2011.2162168.

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18

Lawton, G. "Is MIMO the future of wireless communications?" Computer 37, no. 7 (2004): 20–22. http://dx.doi.org/10.1109/mc.2004.57.

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19

Wang, Zhaocheng, and Jiaxuan Chen. "Networked multiple-input-multiple-output for optical wireless communication systems." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2169 (March 2, 2020): 20190189. http://dx.doi.org/10.1098/rsta.2019.0189.

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With the escalation of heterogeneous data traffic, the research on optical wireless communication (OWC) has attracted much attention, owing to its advantages such as wide spectrum, low power consumption and high security. Ubiquitous optical devices, e.g. light-emitting diodes (LEDs) and cameras, are employed to support optical wireless links. Since the distribution of these optical devices is usually dense, multiple-input-multiple-output (MIMO) can be naturally adopted to attain spatial diversity gain or spatial multiplexing gain. As the scale of OWC networks enlarges, optical MIMO can also collaborate with network-level operations, like user/AP grouping, to enhance the network throughput. Since OWC is preferred for short-range communications and is sensitive to the directions/rotations of transceivers, optical MIMO links vary frequently and sharply in outdoor scenarios when considering the mobility of optical devices, raising new challenges to network design. In this work, we present an overview of optical MIMO techniques, as well as the cooperation of MIMO and user/AP grouping in OWC networks. In consideration of the challenges for outdoor OWC, key technologies are then proposed to facilitate the adoption of optical MIMO in outdoor scenarios, especially in vehicular ad hoc networks. Lastly, future applications of MIMO in OWC networks are discussed. This article is part of the theme issue ‘Optical wireless communication’.

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20

Lee, Doohwan, Hirofumi Sasaki, Hiroyuki Fukumoto, Yasunori Yagi, and Takashi Shimizu. "An Evaluation of Orbital Angular Momentum Multiplexing Technology." Applied Sciences 9, no. 9 (April 26, 2019): 1729. http://dx.doi.org/10.3390/app9091729.

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This paper reports our investigation of wireless communication performance obtained using orbital angular momentum (OAM) multiplexing, from theoretical evaluation to experimental study. First, we show how we performed a basic theoretical study on wireless OAM multiplexing performance regarding modulation, demodulation, multiplexing, and demultiplexing. This provided a clear picture of the effects of mode attenuation and gave us insight into the potential and limitations of OAM wireless communications. Then, we expanded our study to experimental evaluation of a dielectric lens and end-to-end wireless transmission on 28 gigahertz frequency bands. To overcome the beam divergence of OAM multiplexing, we propose a combination of multi-input multi-output (MIMO) and OAM technology, named OAM-MIMO multiplexing. We achieved 45 Gbps (gigabits per second) throughput using OAM multiplexing with five OAM modes. We also experimentally demonstrated the effectiveness of the proposed OAM-MIMO multiplexing using a total of 11 OAM modes. Experimental OAM-MIMO multiplexing results reached a new milestone for point-to-point transmission rates when 100 Gbps was achieved at a 10-m transmission distance.

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21

Imoize, Agbotiname Lucky, Augustus Ehiremen Ibhaze, Aderemi A. Atayero, and K. V. N. Kavitha. "Standard Propagation Channel Models for MIMO Communication Systems." Wireless Communications and Mobile Computing 2021 (February 15, 2021): 1–36. http://dx.doi.org/10.1155/2021/8838792.

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The field of wireless communication networks has witnessed a dramatic change over the last decade due to sophisticated technologies deployed to satisfy various demands peculiar to different data-intensive wireless applications. Consequently, this has led to the aggressive use of the available propagation channels to fulfill the minimum quality of service (QoS) requirement. A major barometer used to gauge the performance of a wireless communication system is the spectral efficiency (SE) of its communication channels. A key technology used to improve SE substantially is the multiple input multiple output (MIMO) technique. This article presents a detailed survey of MIMO channel models in wireless communication systems. First, we present the general MIMO channel model and identified three major MIMO channel models, viz., the physical, analytical, and standardized models. The physical models describe the MIMO channel using physical parameters. The analytical models show the statistical features of the MIMO channel with respect to the measured data. The standardized models provide a unified framework for modern radio propagation architecture, advanced signal processing, and cutting-edge multiple access techniques. Additionally, we examined the strengths and limitations of the existing channel models and discussed model design, development, parameterization, implementation, and validation. Finally, we present the recent 3GPP-based 3D channel model, the transitioning from 2D to 3D channel modeling, discuss open issues, and highlight vital lessons learned for future research exploration in MIMO communication systems.

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22

Chien-Hsiang Wu, Chien-Hsiang Wu, and Chin-Feng Lai Chien-Hsiang Wu. "Data-driven Diversity Antenna Selection for MIMO Communication using Machine Learning." 網際網路技術學刊 23, no. 1 (January 2022): 001–9. http://dx.doi.org/10.53106/160792642022012301001.

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With the popularity of wireless application environments, smart antenna technology has completely changed the communication system. In order to improve the quality of wireless transmission, smart antennas have been widely used in wireless devices. Wireless signal modeling and prediction machine learning gradually replaced the traditional smart antenna selection method in the antenna selection solution. This article utilizes mobile devices to adjust the diversity antenna pattern for test verification in a MIMO wireless communication environment. The proposed method manipulates signal parameters through error vector magnitude (EVM) and adds data-driven training data. The results show that the SVM and NN methods proposed in this paper are 10.5% and 14% higher than the traditional EVM calculation methods, respectively. Thereby, realize precise antenna adjustment of mobile devices and improving wireless transmission quality.

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23

Guerreiro, João, Rui Dinis, and Luís Campos. "On the Achievable Capacity of MIMO-OFDM Systems in the CathLab Environment." Sensors 20, no. 3 (February 10, 2020): 938. http://dx.doi.org/10.3390/s20030938.

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In the last years, the evolution of digital communications has been harnessed by medical applications. In that context, wireless communications are preferable over wired communications, as they facilitate the work of health technicians by reducing cabling on the stretchers. However, the use of wireless communications is challenging, especially when high data rates and low latencies are required. In those scenarios, multiple-input multiple-output (MIMO) techniques might have an important role, thanks to the high capacity gains that they can exhibit, which ideally increase with the MIMO size. In this work, we study the propagation scenario of a typical medical laboratory through ray-tracing techniques. By taking into account the derived channel model, we study the potential of MIMO techniques in an IEEE 802.11ax environment. Through a set of performance results regarding the system capacity, we show that the MIMO gains might not be as high as supposed in the medical laboratory, being far from the ideal scenario. Therefore, the large data rates required by the modern medical imaging applications might only be achieved with a combination of MIMO systems and large bandwidths.

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24

Nguyen, Hieu Trung, and Phu Huu Bui. "FPGA Implementation of Mimo E-SDM for future communications wireless networks." Science and Technology Development Journal 17, no. 1 (March 31, 2014): 81–91. http://dx.doi.org/10.32508/stdj.v17i1.1296.

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Multiple-input multiple-output (MIMO) systems applying the Eigenbeam-Space Division Multiplexing (E-SDM) technique can be considered as optimal MIMO systems because of providing the highest channel capacity and good communications reliability. In the systems, orthogonal transmission beams are formed between transmit and receive sides; and also optimal transmit input data are adaptively allocated. In addition, a simple detection can be used at receiver to totally eliminate sub-stream interference. Therefore, MIMO E-SDM systems have been considered as a good potential technology for future high speed data transmission networks. Although there have been a lot of technical papers evaluated the systems based on theory analyses and/or computer-based simulation, just few ones have been considered the MIMO E-SDM systems based on hardware design. The main contribution of this paper is to present our own design and implementation of 2x2 and 2x3 MIMO E-SDM systems on FPGA Altera Stratix DSP Development KIT using Verilog HDL, an important step before going to make integrated circuits. The bit-error rate performance the consumption for our design of these systems have shown that our design is successful.

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25

Ding, Jupeng, Chih-Lin I, Jintao Wang, Hui Yang, and Lili Wang. "Performance Comparison of Repetition Coding MIMO Optical Wireless Communications with Distinct Light Beams." Sensors 22, no. 3 (February 7, 2022): 1256. http://dx.doi.org/10.3390/s22031256.

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In current optical wireless communications (OWC) oriented research works, the various multiple input multiple output (MIMO) techniques are introduced and utilized to enhance the coverage performance. Objectively, this Lambertian light beam based MIMO research paradigm neglects the light beam diversity and the potential performance gains. In this work, the distinct non-Lambertian light beams of commercially available light emitting diodes (LEDs) were adopted to configure MIMO OWC links. Specifically, the homogenous and heterogeneous non-Lambertian MIMO configurations were constituted in typical indoor scenarios. Moreover, applying the repetition coding (RC) MIMO algorithm with low complexity, a spatial coverage performance comparison was made between the several above mentioned non-Lambertian configurations and the well-discussed Lambertian MIMO configuration. Numerical results illustrate that the homogeneous NSPW light beam configuration could provide a more than 30 dB average signal to noise ratio (SNR), while the achievable average SNR of the heterogeneous light beam configuration was up to 28.77 dB. On the other side, the counterpart of the Lambertian configuration achieved just about 27.00 dB. Objectively, this work paves the fundamental and essential way for the further design and optimization of MIMO OWC in this novel light beam dimension.

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Salam, Abdul. "Subsurface MIMO: A Beamforming Design in Internet of Underground Things for Digital Agriculture Applications." Journal of Sensor and Actuator Networks 8, no. 3 (August 10, 2019): 41. http://dx.doi.org/10.3390/jsan8030041.

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In underground (UG) multiple-input and multiple-output (MIMO), transmit beamforming is used to focus energy in the desired direction. There are three different paths in the underground soil medium through which the waves propagate to reach the receiver. When the UG receiver receives a desired data stream only from the desired path, then the UG MIMO channel becomes a three-path (lateral, direct, and reflected) interference channel. Accordingly, the capacity region of the UG MIMO three-path interference channel, and the degrees of freedom (multiplexing gain of this MIMO channel) requires careful modeling. Therefore, expressions are required for the degrees of freedom of the UG MIMO interference channel. The underground receiver needs to perfectly cancel the interference from the three different components of the EM waves propagating in the soil medium. This concept is based upon reducing the interference of the undesired components to a minimum level at the UG receiver using the receive beamforming. In this paper, underground environment-aware MIMO using transmit and receive beamforming has been developed. The optimal transmit and receive beamforming, combining vectors under minimal intercomponent interference constraints, are derived. It is shown that UG MIMO performs best when all three components of the wireless UG channel are leveraged for beamforming. The environment-aware UG MIMO technique leads to three-fold performance improvements and paves the way for design and development of next-generation sensor-guided irrigation systems in the field of digital agriculture. Based on the analysis of underground radio-wave propagation in subsurface radio channels, a phased-array antenna design is presented that uses water content information and beam-steering mechanisms to improve efficiency and communication range of wireless underground communications. It is shown that the subsurface beamforming using phased-array antennas improves wireless underground communications by using the array element optimization and soil–air interface refraction adjustment schemes. This design is useful for subsurface communication system where sophisticated sensors and software systems are used as data collection tools that measure, record, and manage spatial and temporal data in the field of digital agriculture.

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27

El Ghzaoui, M., A. Hmamou, J. Foshi, and J. Mestoui. "Compensation of Non-linear Distortion Effects in MIMO-OFDM Systems Using Constant Envelope OFDM for 5G Applications." Journal of Circuits, Systems and Computers 29, no. 16 (June 18, 2020): 2050257. http://dx.doi.org/10.1142/s0218126620502576.

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Orthogonal frequency division multiplexing (OFDM) is a multicarrier transmission system that can achieve high data rate over wireless channels. At the same time, multiple input multiple output OFDM (MIMO-OFDM) in wireless communication systems has been exposed to offer significant improvement over wireless technology by providing transmit diversity. It has become a promising technique for high-performance 5G broadband wireless communications. However, the main problem associated with MIMO-OFDM is that its signal exhibits high peak-to-average power ratio (PAPR), which causes nonlinear distortion and consequently performance degradation. Besides, PAPR carries weaknesses such as an increase in power consumption of high power amplifier (HPA) and analog to digital converter (ADC). Thus, 5G base stations will push up power requirements because energy consumption grows with the number of transceiver elements. So, mobile operators must find the right compromise that, on the one hand, guarantees a certain level of performance to a data flow, and, on the other hand, the energy cost generated for the deployment of the network. For this, as part of the management of power consumption, we propose MIMO constant envelope OFDM (MIMO-CE-OFDM) technique. In this work, we used MIMO-CE-OFDM to mitigate the nonlinear effect of HPA and ADC. To perform practical simulations, we have used COST 2100 MIMO channel model. In this paper, a MIMO-CE-OFDM system has been presented and analyzed under COST 2100 channel model conditions. Simulation results are given to illustrate the performance of [Formula: see text] MIMO-CE-OFDM in the presence of both HPA and ADC nonlinearity. This work shows that the effect of nonlinearity is shown to be negligible on MIMO-CE-OFDM signal.

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28

Jit Singh, Mandeep Singh, Wan Syahrum Wan Saleh, Amer T. Abed, and Muhammad Ashraf Fauzi. "A Review on Massive MIMO Antennas for 5G Communication Systems on Challenges and Limitations." Jurnal Kejuruteraan 35, no. 1 (January 30, 2023): 95–103. http://dx.doi.org/10.17576/jkukm-2023-35(1)-09.

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High data rate transfers, high-definition streaming, high-speed internet, and the expanding of the infrastructure such as the ultra-broadband communication systems in wireless communication have become a demand to be considered in improving quality of service and increase the capacity supporting gigabytes bitrate. Massive Multiple-Input Multiple-Output (MIMO) systems technology is evolving from MIMO systems and becoming a high demand for fifth-generation (5G) communication systems and keep expanding further. In the near future, massive MIMO systems could be the main wireless systems of communications technology and can be considered as a key technology to the system in daily lives. The arrangement of the huge number of antenna elements at the base station (BS) for uplink and downlink to support the MIMO systems in increasing its capacity is called a Massive MIMO system, which refers to the vast provisioning of antenna elements at base stations over the number of the single antenna of user equipment. Massive MIMO depends on spatial multiplexing and diversity gain in serving users with simple processing signal of uplink and downlink at the BS. There are challenges in massive MIMO system even though it contains numerous number of antennas, such as channel estimation need to be accurate, precoding at the BS, and signal detection which is related to the first two items. On the other hand, in supporting wideband cellular communication systems and enabling low latency communications and multi-gigabit data rates, the Millimeter-wave (mmWave) technology has been utilized. Also, it is widely influenced the potential of the fifth-generation (5G) New Radio (NR) standard. This study was specifically review and compare on a few designs and methodologies on massive MIMO antenna communication systems. There are three limitations of those antennas were identified to be used for future improvement and to be proposed in designing the massive MIMO antenna systems. A few suggestions to improve the weaknesses and to overcome the challenges have been proposed for future considerations.

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29

Hoffmann, Leah. "Bringing stability to wireless connections." Communications of the ACM 64, no. 2 (January 25, 2021): 120. http://dx.doi.org/10.1145/3441293.

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30

Pawelec, J., M. Suchański, K. Kosmowski, and T. Szymczyk. "The OSA-MIMO Technologies for Future Wireless Communications." Universal Journal of Communications and Network 1, no. 2 (September 2013): 56–59. http://dx.doi.org/10.13189/ujcn.2013.010204.

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31

Chen, Hongyang, Fauzia Ahmad, Sergiy Vorobyov, and Fatih Porikli. "Tensor Decompositions in Wireless Communications and MIMO Radar." IEEE Journal of Selected Topics in Signal Processing 15, no. 3 (April 2021): 438–53. http://dx.doi.org/10.1109/jstsp.2021.3061937.

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32

Haykin, S., K. Huber, and Z. Chen. "Bayesian Sequential State Estimation for MIMO Wireless Communications." Proceedings of the IEEE 92, no. 3 (March 2004): 439–54. http://dx.doi.org/10.1109/jproc.2003.823143.

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33

Blum, R. S., H. Bolcskei, M. P. Fitz, B. Hughes, and A. J. Paulraj. "Guest editorial special issue on mimo wireless communications." IEEE Transactions on Signal Processing 51, no. 11 (November 2003): 2709. http://dx.doi.org/10.1109/tsp.2003.818198.

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34

Castillo-Soria, F. R., Joaquin Cortez, C. A. Gutiérrez, M. Luna-Rivera, and A. Garcia-Barrientos. "Extended quadrature spatial modulation for MIMO wireless communications." Physical Communication 32 (February 2019): 88–95. http://dx.doi.org/10.1016/j.phycom.2018.11.006.

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35

Sapenov, Yerzhan, Anas Chaaban, Zouheir Rezki, Mohamed Abdallah, Khalid Qaraqe, and Mohamed-Slim Alouini. "Diversity Order Results for MIMO Optical Wireless Communications." IEEE Wireless Communications Letters 7, no. 1 (February 2018): 74–77. http://dx.doi.org/10.1109/lwc.2017.2755011.

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36

Hazer Sahlabadi, Mehran, Abdolali Abdipour, and Abbas Mohammadi. "A seven-port receiver for MIMO wireless communications." Analog Integrated Circuits and Signal Processing 101, no. 2 (July 25, 2019): 243–53. http://dx.doi.org/10.1007/s10470-019-01508-9.

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37

Agrawal, Anurag Vijay, and Meenakshi Rawat. "Reliable Integrated Satellite Terrestrial Communications using MIMO for Mitigation of Microwave Absorption by Earths Oxygen." Defence Science Journal 69, no. 5 (September 17, 2019): 458–63. http://dx.doi.org/10.14429/dsj.69.14951.

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Microwaves are used to communicate with satellite and terrestrial communication networks. But as microwaves pass through the Earth’s atmosphere, the oxygen gas absorbs microwave. In this 5G era, when the whole world is moving towards high data-rates and reliable communications, this absorption affects the data transmission in Integrated Satellite/Terrestrial Communication (ISTC) systems, which leads to degradation of the system performance. The multiple-input-multiple-output (MIMO) technology has become a boon for modern wireless communication systems to achieve the necessities of higher data-rates and communication reliability. The paper analyses the MIMO effect on block error rate (BLER), error vector magnitude (EVM) and throughput performance of the data transmission with different MIMO configurations. The paper establishes that better data-rates as well as reliable data communication is achieved with higher order MIMO configurations. MIMO 8×1 provides 5, 20 and 42.5 times improved performance to BLER; 5.26%, 25% and 81.82% in throughput; and 10.34%, 23.07% and 28% in EVM calculations as comparable to MIMO 4×1, MIMO 2×1 and SISO 1×1, respectively at 15 dB signal-to-noise ratio (SNR). The authors also give a new concept of multi-cellular layers based mobile communication network, useful for future smart cities.

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38

Nej, Sanjukta, Anumoy Ghosh, Sarosh Ahmad, Adnan Ghaffar, and Mousa Hussein. "Compact Quad Band MIMO Antenna Design with Enhanced Gain for Wireless Communications." Sensors 22, no. 19 (September 21, 2022): 7143. http://dx.doi.org/10.3390/s22197143.

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In this paper, a novel microstrip line-fed meander-line-based four-elements quad band Multiple Input and Multiple Output (MIMO) antenna is proposed with a gain enhancement technique. The proposed structure resonates at four bands simultaneously, that is, 1.23, 2.45, 3.5 and 4.9 GHz, which resemble GPS L2, Wi-Fi, Wi-MAX and WLAN wireless application bands, respectively. The unit element is extended to four elements MIMO antenna structure exhibiting isolation of more than 22 dB between the adjacent elements without disturbing the resonant frequencies. In order to enhance the gain, two orthogonal microstrip lines are incorporated between the antenna elements which result in significant gain improvement over all the four resonances. Furthermore, the diversity performance of the MIMO structure is analyzed. The Envelope Co-Relation Coefficient (ECC), Diversity Gain (DG), Channel Capacity Loss (CCL), Mean Effective Gain (MEG) and Multiplexing Efficiency are obtained as 0.003, 10 dB, 0.0025 bps/Hz, −3 dB (almost) and 0.64 (min.), respectively, which are competent and compatible with practical wireless applications. The Total Active Reflection Coefficient (TARC) resembles the characteristic of the individual antenna elements. The layout area of the overall MIMO antenna is 0.33 λ × 0.29 λ, where λ is the free-space wavelength corresponding to the lowest resonance. The advantage of the proposed structure has been assessed by comparing it with previously reported MIMO structures based on number of antenna elements, isolation, gain, CCL and compactness. A prototype of the proposed MIMO structure is fabricated, and the measured results are found to be aligned with the simulated results.

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39

Zaki, Amira I., Mahmoud Nassar, Moustafa H. Aly, and Waleed K. Badawi. "A Generalized Spatial Modulation System Using Massive MIMO Space Time Coding Antenna Grouping." Entropy 22, no. 12 (November 30, 2020): 1350. http://dx.doi.org/10.3390/e22121350.

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Massive multiple input multiple output (MIMO), also known as a very large-scale MIMO, is an emerging technology in wireless communications that increases capacity compared to MIMO systems. The massive MIMO communication technique is currently forming a major part of ongoing research. The main issue for massive MIMO improvements depends on the number of transmitting antennas to increase the data rate and minimize bit error rate (BER). To enhance the data rate and BER, new coding and modulation techniques are required. In this paper, a generalized spatial modulation (GSM) with antenna grouping space time coding technique (STC) is proposed. The proposed GSM-STC technique is based on space time coding of two successive GSM-modulated data symbols on two subgroups of antennas to improve data rate and to minimize BER. Moreover, the proposed GSM-STC system can offer spatial diversity gains and can also increase the reliability of the wireless channel by providing replicas of the received signal. The simulation results show that GSM-STC achieves better performance compared to conventional GSM techniques in terms of data rate and BER, leading to good potential for massive MIMO by using subgroups of antennas.

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40

Al-Ani, N. M. K., O. A. S. Al-Ani, M. F. Mosleh, and R. A. Abd-Alhameed. "A Design of MIMO Prototype in C-Band Frequency for Future Wireless Communications." Advanced Electromagnetics 9, no. 1 (March 22, 2020): 78–84. http://dx.doi.org/10.7716/aem.v9i1.1333.

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The main challenges of MIMO design for future wireless communication is size reduction which leads to more mutual coupling. This paper deals with this problem in order to mitigate the impact of mutual coupling by proposing four elements MIMO prototype each one having a dual polarized patch rectangular microstrips. The idea is to insert annular rectangular opened one ribs in front of each microstrip and in corresponding to circular ring slot etched has etched in the ground. The advantage of such slot is to obtain regular radiation pattern distributed around device body. The four elements with eight ports are incorporated on 67×139 mm2 PCB with FR-4 dielectric layer. The single antenna is simulated CST.STUDIO 2019 resulting an operated frequency of 6.23 GHz with a band of 850 MHz (5.81-6.66) GHz at -10 dB. The fabrication MIMO system prototype is tested to show its measurement results which are match the simulated results. All results confirm of that proposed MIMO prototype which is operated at C-band frequency which is very important for future wireless applications.

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41

P., Karrupusamy. "MIMO BASED HIGH SPEED OPTICAL FIBER COMMUNICATION SYSTEM." December 2019 2019, no. 02 (December 29, 2019): 107–16. http://dx.doi.org/10.36548/jei.2019.2.006.

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As the telecommunication services totally relies on the optical fiber for extending communications, it necessary that the optical communication system be capable of handling high speed, multiple channels and long haul signal transmission. recently the emergence of the optical coherent 100 GB/s and the digital signal processing has made possible the perfect signal transmission even for the MIMO (multiple input multiple output system) as they are well reformed to permit multiple wireless signal that holds different carrier frequencies. So the optical fiber system has become prominent among the applications like, large universities, banks and other private networks. However the speed in the transmission of the multiple wireless signals through single cable experiences performance issues in terms of speed, so the proposed method utilizes the 60 GHz, radio over fiber MIMO with effective spectrum allocation and the return zero differential phase shift keying to improve the communication speed and suppress the crosstalk respectively. The proposed system enriches the seamless communication with the QPSK-OFDM MIMO channels achieving 85 % in the data transmission rate, reducing the error correction rate to 5%.

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42

Ahmed, Md Firoz, Md Tahidul Islam, and Abu Zafor Md. Touhidul Islam. "Performance of Convolution and CRC Channel Encoded V-Blast 4x4 MIMO MC-CDMA Wireless Communication System." International Journal of Ambient Systems and Applications 9, no. 2 (June 30, 2021): 1–6. http://dx.doi.org/10.5121/ijasa.2021.9201.

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Wireless communications are among the rapidly growing fields in our current life and have a massive effect on every aspect of our everyday life. In this paper, the performance of the various digital modulation techniques (BPSK, DPSK, QPSK, and QAM) based wireless communication system on the audio signal transmission through the additive Gaussian Noise (AWGN) channel is assessed on the basis of bit error rate (BER) as a function of the signal-to-noise ratio (SNR). Based on the results of this study, BPSK modulation outperforms the DPSK, QPSK, and QAM modulation strategies in the MIMO MC-CDMA VBlast based wireless communication system. The digital modulation of QPSK shows the worst performance in audio signal transmission especially in comparison to other digital modulations. It is clear from the current simulation study based on MATLAB that the V-Blast encoded 4×4 MIMO MC-CDMA wireless system with minimum mean square error (MMSE) signal detection and 1⁄2-rated convolution and cyclic redundancy check (CRC) channel encoding strategies show good performance utilizing BPSK digital modulation in audio signal transmission.

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43

Khaleel, Sherif A., Ehab K. I. Hamad, Naser Ojaroudi Parchin, and Mohamed B. Saleh. "MTM-Inspired Graphene-Based THz MIMO Antenna Configurations Using Characteristic Mode Analysis for 6G/IoT Applications." Electronics 11, no. 14 (July 9, 2022): 2152. http://dx.doi.org/10.3390/electronics11142152.

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6G wireless communications will be immersed in the future with different applications. It is expected to support all IoT services and satellite communications, and it is expected to support artificial intelligence (AI) and machine learning (ML). The THz frequency band has a vital role in 6G communication. In this study, a new graphene plasmonic two-port Terahertz (THz) MIMO antenna is analyzed by the characteristic mode theory (CMA), which gives a better insight into the physical behavior of the MIMO configurations. The proposed MIMO antenna is compact and designed on a Teflon substrate of 130 × 85 µm2. The antenna provides a wide impedance bandwidth of 0.6 THz (3.2–3.8 THz). The CMA is applied to clarify the position at which the mutual coupling gives a maximum concentrated current distribution. It is mainly used to reveal the preferable MIMO antenna configuration by the usage of the model significant and model current distribution property. To reduce the mutual coupling between the radiating elements, a complementary dumbbell-structure Metamaterial (MTM) unit cell is etched in the ground plane to block the coupling mode without any affection on the dominant mode. The preferred MIMO configuration gives high isolation of −55 dB between the radiating patches. The fundamental characteristics have been discussed in detail. The proposed MIMO design offers several attractive features such as large bandwidth of 0.6 THz, low envelope correlation coefficient (ECC) of 0.000168, compact size, stable radiation, high gain of 7.23 dB, and low channel capacity loss (CCL) of 0.006. The proposed MIMO design is suitable for different applications in the THz band according to the high-performance parameters such as biomedical applications, security scanning, sensing, IoT, and 6G high-speed wireless communication systems.

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44

Markiewicz, Tomasz G., and Krzysztof W. Wesołowski. "Cryogenic Cooling in Wireless Communications." Entropy 21, no. 9 (August 25, 2019): 832. http://dx.doi.org/10.3390/e21090832.

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Improving the capacity and performance of communication systems is typically achieved by either using more bandwidth or enhancing the effective signal-to-noise ratio (SNR). Both approaches have led to the invention of various transmission techniques, such as forward error correction (FEC), multiple-input multiple-output (MIMO), non-orthogonal multiple access (NOMA), and many, many others. This paper, however, focuses on the idea that should be immediately apparent when looking at Shannon’s channel capacity formula, but that somehow remained less explored for decades, despite its (unfortunately only in theory) limitless potential. We investigate the idea of improving the performance of communication systems by means of cryogenic cooling of their RF front-ends; the technique, although widely-known and used in radio astronomy for weak signal detection, has attracted limited interest when applied to wireless communications. The obtained results, though mainly theoretical, are promising and lead to a substantial channel capacity increase, implying an increase in spectral efficiency, potential range extension, or decreasing the power emitted by mobile stations. We see its applications in base stations (BSs) of machine-type communication (MTC) and Internet of Things (IoT) systems.

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45

Shi, Yan, Lu Zhang, and Chang-Hong Liang. "Dual Zeroth-Order Resonant USB Dongle Antennas for 4G MIMO Wireless Communications." International Journal of Antennas and Propagation 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/816051.

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A multiband multiple-input multiple-output (MIMO) antenna system consisting of two antenna elements has been proposed for 4G USB dongle application. The designed MIMO antenna system with a compact volume of 25 mm × 30 mm × 3.5 mm operates in two zeroth-order resonance (ZOR) modes to cover the LTE band 13 (746–787 MHz), GSM850/900 (824–960 MHz), and LTE band 7 (2500–2690 MHz) simultaneously. A pair of L-shaped parasitic strips and an etching slot on the ground are employed to achieve good isolation between two elements. Measurement results show that proposed MIMO antenna system has total efficiency over 40% across the operation band and isolation less than −8 dB at the lower band and −16 dB at the upper band, respectively.

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46

Hikmat Abd, Reem, and Hussein Ali Abdulnabi. "Design of graphene-based multi-input multi-output antenna for 6G/IoT applications." Indonesian Journal of Electrical Engineering and Computer Science 31, no. 1 (July 1, 2023): 212. http://dx.doi.org/10.11591/ijeecs.v31.i1.pp212-221.

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In the future, 6G wireless communications will be integrated into various applications. It is expected that it will handle all Internet of Things services as well as satellite communications. Additionally, it is predicted to support machine learning (ML) and artificial intelligence (AI). So this work investigated four orthogonal ports graphene-based multiple-input and multiple-output (MIMO) antenna in the terahertz frequency regime. With wide-band (7.1-13) THz, minimum return loss close to -30 dB and a good isolation value. That was designed over silicon dioxide (Sio2) 100×100 substrate with a thickness of 10 µm and a maximum gain reaching 8.3 dB at 11 THz. By adjusting the provided DC voltage, the chemical potential of graphene can be tuned, which in turn allows for the MIMO antenna characteristics to be changed. Envelop correlation coefficient (ECC) and diversity gain (DG) were investigated for the presented design. In addition, these values were determined to assess compatibility and difficulties connected with communication over a short distance. The geometry of the MIMO antenna is adaptable to various applications in the THz band with highperformance requirements, such as sensing, scanning for security threats, biomedical applications, wireless communication systems with high speed built on the 6G standard, and the internet of things (IoT).

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47

Kei Sakaguchi, Takumi Yoneda, Masashi Iwabuchi, and Tomoki Murakami. "mmWave massive analog relay MIMO." ITU Journal on Future and Evolving Technologies 2, no. 6 (September 24, 2021): 43–55. http://dx.doi.org/10.52953/wzof2275.

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Millimeter-Wave (mmWave) communications are a key technology to realize ultra-high data rate and ultra-low latency wireless communications. Compared with conventional communication systems in the microwave band such as 4G/LTE, mmWave communications employ a higher frequency band which allows a wider bandwidth and is suitable for large capacity communications. It is expected to be applied to various use cases such as mmWave cellular networks and vehicular networks. However, due to the strong diffraction loss and the path loss in the mmWave band, it is difficult or even impossible to achieve high channel capacity for User Equipment (UE) located in Non-Line-Of-Sight (NLOS) environments. To solve the problem, the deployment of relay nodes has been considered. In this paper, we consider the use of massive analog Relay Stations (RSs) to relay the transmission signals. By relaying the signals by a large number of RSs, an artificial Multiple-Input Multiple-Output (MIMO) propagation environment can be formed, which enables mmWave MIMO communications to the NLOS environment. We describe a theoretical study of a massive relay MIMO system and extend it to include multi-hop relays. Simulations are conducted, and the numerical results show that the proposed system achieves high data rates even in a grid-like urban environment.

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48

Lee, Sang-Hoon, Ahmed Al Amin, and Soo-Young Shin. "Orbital Angular Momentum-Based Multiple-Input-Multiple- Output with Receive Antenna Shift Keying for 6G." Electronics 10, no. 13 (June 29, 2021): 1567. http://dx.doi.org/10.3390/electronics10131567.

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Spectral efficiency is a major concern for future 6G wireless communication systems. Thus, an appropriate scheme is needed to provide channel capacity improvement for multiple transmitters and receiver-based wireless communication systems without consuming extra resource for communication (e.g., frequency/time/code) or causing interference. Therefore, to fulfill the mentioned requirements for the future 6G wireless network, orbital angular momentum-based multiple-input-multiple-output (OAM-MIMO) multiplexing technique is incorporated with the receive antenna shift keying (RASK) technique in this study (termed as the OAM-MIMO-RASK scheme). OAM-MIMO-RASK can transfer multiple symbols from multiple transmitters to different receivers simultaneously by using multiple subchannels using the OAM and RASK techniques without any interference or additional resource (frequency/time/code). The numerical results illustrated that the proposed OAM-MIMO-RASK can achieve almost double capacity than the existing OAM-MIMO scheme and significantly higher capacity than the existing RASK-based scheme for different values of signal-to-noise ratio. Moreover, the simulation result is validated by the theoretical result which is also shown by the numerical result. In addition, due to different normalized distances from the transmitters and receivers, the proposed OAM-MIMO-RASK scheme can achieve almost double capacity than the existing OAM-MIMO scheme by using OAM-MIMO and RASK technique effectively which is also depicted by the numerical results.

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49

Ding, Mingjun, Xiaodong Yang, Rui Hu, Zhitao Xiao, Jun Tong, and Jiangtao Xi. "On Matrix Completion-Based Channel Estimators for Massive MIMO Systems." Symmetry 11, no. 11 (November 6, 2019): 1377. http://dx.doi.org/10.3390/sym11111377.

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Large-scale symmetric arrays such as uniform linear arrays (ULA) have been widely used in wireless communications for improving spectrum efficiency and reliability. Channel state information (CSI) is critical for optimizing massive multiple-input multiple-output(MIMO)-based wireless communication systems. The acquisition of CSI for massive MIMO faces challenges such as training shortage and high computational complexity. For millimeter wave MIMO systems, the low-rankness of the channel can be utilized to address the challenge of training shortage. In this paper, we compared several channel estimation schemes based on matrix completion (MC) for symmetrical arrays. Performance and computational complexity are discussed and compared. By comparing the performance in different scenarios, we concluded that the generalized conditional gradient with alternating minimization (GCG-Alt) estimator provided a low-cost, robust solution, while the alternating direction method of multipliers (ADMM)-based hybrid methods achieved the best performance when the array response was perfectly known.

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50

Ghayoula, E., A. Bouallegue, R. Ghayoula, and J.-Y. Chouinard. "Capacity and Performance of MIMO systems for Wireless Communications." Journal of Engineering Science and Technology Review 7, no. 3 (August 2014): 108–11. http://dx.doi.org/10.25103/jestr.073.17.

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