scholarly journals GA-MIMO: Genetic Algorithm for Optimization of ESPAR Antenna on Beamspace MIMO

2019 ◽  
Vol 17 (1) ◽  
pp. 1
Author(s):  
Rissa Rahmania ◽  
Bambang Setia Nugroho ◽  
Fiky Yosef Suratman ◽  
Suryo Adhi Wibowo
Keyword(s):  
Genetic Algorithm ◽  
Radiation Pattern ◽  
Mimo System ◽  
Multiple Input Multiple Output ◽  
Schmidt Method ◽  
Antenna Structure ◽  
Channel Condition ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Rf Chain

<p><em>An electronically steerable passive array radiator (ESPAR) antenna can be used on a beamspace (BS)-multiple input multiple output (MIMO) system to reduce the device complexity. An ESPAR antenna has beamforming ability with single RF chain. However, antenna structure and channel conditions affect the number of orthogonal basis pattern which generated using Gram-Schmidt method. Based on this problem, reactance value at each parasitic element need to be optimized to form radiation pattern that required by the BS-MIMO. In this research, Genetic Algorithm (GA) is used to optimize reactance value which represented by the correlation between the desired and achieved radiation pattern, in different number of elements and different channel condition. GA is selected because this problem can be modeled as chromosome and several individual. Furthermore, the result shows in channel-ignorant and channel-aware, antenna with seven elements has a correlation in median value of 99.46% and 90.58%, respectively.</em></p><p><em> <em>Antena electronically steerable passive array radiator (ESPAR) dapat digunakan dalam sistem beamspace (BS)-multiple input multiple output (MIMO) dalam mengatasi kompleksitas perangkat. Antena ESPAR memiliki kemampuan untuk membentuk pola radiasi pada arah tertentu dengan menggunakan terminal tunggal, namun struktur antena dan kondisi kanal mempengaruhi pola dasar ortogonal yang dihasilkan melalui metode Gram Schmidt. Berdasarkan permasalahan tersebut, nilai reaktansi pada setiap elemen parasit perlu dioptimasi sehingga dapat menghasilkan pola radiasi yang dibutuhkan oleh sistem BS-MIMO. Pada penelitian ini, Algoritma Genetika digunakan untuk mengoptimasi nilai reaktansi yang direpresentasikan melalui korelasi antara pola radiasi yang dibutuhkan dengan pola radiasi yang dihasilkan, dalam jumlah elemen yang berbeda dan kondisi kanal yang berbeda. AG dipilih karena permasalahan ini dapat dimodelkan sebagai kromosom dan beberapa individual. Hasil analisis pada kondisi channel-ignorant dan channel-aware menunjukkan bahwa antena dengan tujuh elemen memiliki korelasi nilai median sebesar 99,46% dan 90,58%.</em></em></p>

Compact UWB–MIMO antenna with quad-band-notched characteristic

2016 ◽  
Vol 9 (5) ◽  
pp. 1147-1153 ◽  
Author(s):  
Ling Wu ◽  
Yingqing Xia
Keyword(s):  
Correlation Coefficient ◽  
Radiation Pattern ◽  
Mimo System ◽  
Ground Plane ◽  
Multiple Input Multiple Output ◽  
Mimo Antenna ◽  
X Band ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Better Than

With quad-band-notched characteristic, a compact ultrawideband (UWB) multiple-input-multiple-output (MIMO) antenna is introduced in the paper. The UWB–MIMO system has two similar monopole elements and occupies 30 × 45 mm2. By inserting two L-shaped slots, CSRR and C-shaped stubs, four notched bands are achieved (3.25–3.9, 5.11–5.35, 5.5–6.06, and 7.18–7.88 GHz) to filter WiMAX, lower WLAN, upper WLAN, and X-band. Meanwhile, the isolation is obviously enhanced with three metal strips on the ground plane. Results indicate that the antenna covers UWB frequency band of 3.1 – 10.6 GHz except four rejected bands, isolation of better than −18 dB, envelope correlation coefficient of <0.02, and good radiation pattern, thus making it useful for UWB systems.

Experimental investigation of beam-steering applied to 2 × 2 MIMO system with single receiving RF chain and time-modulated antenna array

2020 ◽  
Vol 12 (6) ◽  
pp. 504-512
Author(s):  
Grzegorz Bogdan ◽  
Konrad Godziszewski ◽  
Yevhen Yashchyshyn
Keyword(s):  
Experimental Investigation ◽  
Antenna Array ◽  
Software Defined Radio ◽  
Mimo System ◽  
Beam Steering ◽  
Multiple Input Multiple Output ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Considerable Impact ◽  
Rf Chain

AbstractMultiple antennas and multiple radio frequency (RF) chains in both the transmitter and receiver are required in conventional radio systems employing the multiple-input multiple-output (MIMO) method. This paper presents an experimental investigation of a beam-steering time-modulated MIMO receiver with a single RF chain. Implementation of the receiver is based on a time-modulated antenna array (TMAA) and a software-defined radio. The sidebands generated inherently by the TMAA are utilized as virtual spatial channels with the beam-steering functionality. Performance of the system is investigated experimentally. The bit error rate and condition number of the channel matrix are examined for different radiation patterns in order to determine favorable configurations in a given multipath environment. Obtained results show a considerable impact of the beam-steering on the performance of MIMO transmission.

scholarly journals A Survey on Spatial Modulation and MIMO System for Emerging Wireless Communication

2021 ◽  
Vol 9 (VI) ◽  
pp. 3059-3062
Author(s):  
Prabha Kumari
Keyword(s):  
Wireless Communication ◽  
Mimo Systems ◽  
Mimo System ◽  
Multiple Input Multiple Output ◽  
High Energy ◽  
Spatial Modulation ◽  
Bandwidth Efficiency ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Rf Chain

In this paper we have studied about Spatial Modulation (SM) in MIMO system. Spatial modulation is a unique and newly proposed technique. Spatial modulation is a multiple input multiple output technique which provides higher throughput and gain as compared to Quadrature Amplitude Modulation. Spatial modulation is a technique which enhances the performance of MIMO system. Spatial modulation and MIMO technique are used to attracted research for its high energy and spectral efficiency because it is working on single RF chain. This paper has considered the advantages of spatial modulation and MIMO systems, using different technique to improve the bandwidth efficiency. Some of such MIMO systems applications are discussed wherein become a requirement for an emerging wireless communication system.

A companding approach for PAPR suppression in OFDM based massive MIMO system

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ajay Kumar Yadav ◽  
Pritam Keshari Sahoo ◽  
Yogendra Kumar Prajapati
Keyword(s):  
Massive Mimo ◽  
Orthogonal Frequency Division Multiplexing ◽  
Mimo System ◽  
Multiple Input Multiple Output ◽  
Average Power ◽  
Base Station ◽  
Convex Optimization Problem ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Mimo Ofdm

Abstract Orthogonal frequency division multiplexing (OFDM) based massive multiuser (MU) multiple input multiple output (MIMO) system is popularly known as high peak-to-average power ratio (PAPR) issue. The OFDM-based massive MIMO system exhibits large number of antennas at Base Station (BS) due to the use of large number of high-power amplifiers (HPA). High PAPR causes HPAs to work in a nonlinear region, and hardware cost of nonlinear HPAs are very high and also power inefficient. Hence, to tackle this problem, this manuscript suggests a novel scheme based on the joint MU precoding and PAPR minimization (PP) expressed as a convex optimization problem solved by steepest gradient descent (GD) with μ-law companding approach. Therefore, we develop a new scheme mentioned to as MU-PP-GDs with μ-law companding to minimize PAPR by compressing and enlarging of massive MIMO OFDM signals simultaneously. At CCDF = 10−3, the proposed scheme (MU-PP-GDs with μ-law companding for Iterations = 100) minimizes the PAPR to 3.70 dB which is better than that of MU-PP-GDs, (iteration = 100) as shown in simulation results.

scholarly journals Genetic Algorithm-Based Beam Refinement for Initial Access in Millimeter Wave Mobile Networks

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Hao Guo ◽  
Behrooz Makki ◽  
Tommy Svensson
Keyword(s):  
Genetic Algorithm ◽  
Millimeter Wave ◽  
Mobile Networks ◽  
System Performance ◽  
Multiple Input Multiple Output ◽  
Hardware Impairments ◽  
Mimo Networks ◽  
Multiple Input ◽  
Input Multiple Output ◽  
High Carrier

Initial access (IA) is identified as a key challenge for the upcoming 5G mobile communication system operating at high carrier frequencies, and several techniques are currently being proposed. In this paper, we extend our previously proposed efficient genetic algorithm- (GA-) based beam refinement scheme to include beamforming at both the transmitter and the receiver and compare the performance with alternative approaches in the millimeter wave multiuser multiple-input-multiple-output (MU-MIMO) networks. Taking the millimeter wave communications characteristics and various metrics into account, we investigate the effect of different parameters such as the number of transmit antennas/users/per-user receive antennas, beamforming resolutions, and hardware impairments on the system performance employing different beam refinement algorithms. As shown, our proposed GA-based approach performs well in delay-constrained networks with multiantenna users. Compared to the considered state-of-the-art schemes, our method reaches the highest service outage-constrained end-to-end throughput with considerably less implementation complexity. Moreover, taking the users’ mobility into account, our GA-based approach can remarkably reduce the beam refinement delay at low/moderate speeds when the spatial correlation is taken into account. Finally, we compare the cases of collaborative users and noncollaborative users and evaluate their difference in system performance.

scholarly journals Energy and Information Beamforming in Airborne Massive MIMO System for Wireless Powered Communications

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3540 ◽  
Author(s):  
Yurong Wang ◽  
Aijun Liu ◽  
Kui Xu ◽  
Xiaochen Xia
Keyword(s):  
Mimo System ◽  
Multiple Input Multiple Output ◽  
Hardware Complexity ◽  
Mimo Channels ◽  
Channel State ◽  
Active Antennas ◽  
Large Numbers ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Critical Problems

Energy supply and information backhaul are critical problems for wireless sensor networks deployed in remote places with poor infrastructure. To deal with these problems, this paper proposes an airborne massive multiple-input multiple-output (MIMO) system for wireless energy transfer (WET) and information transmission. An air platform (AP) equipped with a two-dimensional rectangular antenna array is employed to broadcast energy and provide wireless access for ground sensors. By exploiting the statistical property of air-terrestrial MIMO channels, the energy and information beamformers are jointly designed to maximize the average received signal-to-interference-plus-noise ratio (SINR), which gives rise to a statistical max-SINR beamforming scheme. The scheme does not rely on the instantaneous channel state information, but still requires large numbers of RF chains at AP. To deal with this problem, a heuristic strongest-path energy and information beamforming scheme is proposed, which can be implemented in the analog-domain with low computational and hardware complexity. The analysis of the relation between the two schemes reveals that, with proper sensor scheduling, the strongest-path beamforming is equivalent to the statistical max-SINR beamforming when the number of AP antennas tends to infinity. Using the asymptotic approximation of average received SINR at AP, the system parameters, including transmit power, number of active antennas of AP and duration of WET phase, are optimized jointly to maximize the system energy efficiency. The simulation results demonstrate that the proposed schemes achieve a good tradeoff between system performance and complexity.

Precoding for Multiuser MIMO

2012 ◽  
pp. 130-156 ◽  
Author(s):  
Elsadig Saeid ◽  
Varun Jeoti ◽  
Brahim Belhaouari Samir
Keyword(s):  
Mimo Systems ◽  
Mimo System ◽  
Multiple Input Multiple Output ◽  
Achievable Rate ◽  
Multiple Access Channels ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Single User ◽  
A New Technique ◽  
Improved Technique

Future Wireless Networks are expected to adopt multi-user multiple input multiple output (MU-MIMO) systems whose performance is maximized by making use of precoding at the transmitter. This chapter describes the recent advances in precoding design for MU-MIMO and introduces a new technique to improve the precoder performance. Without claiming to be comprehensive, the chapter gives deep introduction on basic MIMO techniques covering the basics of single user multiple input multiple output (SU-MIMO) links, its capacity, various transmission strategies, SU-MIMO link precoding, and MIMO receiver structures. After the introduction, MU-MIMO system model is defined and maximum achievable rate regions for both MU-MIMO broadcast and MU-MIMO multiple access channels are explained. It is followed by critical literature review on linear precoding design for MU-MIMO broadcast channel. This paves the way for introducing an improved technique of precoding design that is followed by its performance evaluation.

Design of Massive Multiuser MIMO System to Mitigate Inter Antenna Interference and Multiuser Interference in 5G Wireless Networks

2020 ◽  
pp. 693-701 ◽  
Author(s):  
Naga Raju Challa ◽  
◽  
Kalapraveen Bagadi
Keyword(s):  
Communication Networks ◽  
Mimo System ◽  
Multiple Input Multiple Output ◽  
Matrix Computations ◽  
User Terminal ◽  
Multiple Input ◽  
Input Multiple Output ◽  
Major Factors ◽  
Value Decomposition ◽  
User Interference

Massive Multi-user Multiple Input Multiple Output (MU‒MIMO) system is aimed to improve throughput and spectral efficiency in 5G communication networks. Inter-antenna Interference (IAI) and Multi-user Interference (MUI) are two major factors that influence the performance of MU–MIMO system. IAI arises due to closely spaced multiple antennas at each User Terminal (UT), whereas MUI is generated when one UT comes in the vicinity of another UT of the same cellular network. IAI can be mitigated by the use of a pre-coding scheme such as Singular Value Decomposition (SVD) and MUI can be cancelled through efficient Multi-user Detection (MUD) schemes. The highly complex and optimal Maximum Likelihood (ML) detector involves a large number of computations, especially when in massive structures. Therefore, the local search-based algorithm such as Likelihood Ascent Search (LAS) has been found to be a better alternative for mitigation of MUI, as it results in near optimal performance using lesser number of matrix computations. Most of the literature have been aimed at mitigating either IAI or MUI, whereas the proposed work presents SVD pre-coding and LAS MUD to mitigate both IAI and MUI. Simulation results indicate that the proposed scheme can attain near-optimal bit error rate (BER) performance with fewer computations.

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