Transmit and Receive Antenna Selection Based Resource Allocation for Self-Backhaul 5G Massive MIMO HetNets

With the advancement in wireless communication technology, the ease of accessibility and increasing coverage area is a major challenge for service providers. Network densification through Small cell Base Stations (SBS) integration in Heterogeneous Networks (HetNets) promises to improve network performance for cell edge users. Since providing wired backhaul for small cells is not cost effective or practical, the third-Generation Partnership Project (3GPP) has developed architecture for self-backhaul known as Integrated Access and Backhaul (IAB) for Fifth Generation (5G). This allows for Main Base Station (MBS) resources to be shared between SBS and MBS users. However, fair and efficient division of MBS resources remains a problem to be addressed. We develop a novel transmit antenna selection/partitioning technique for taking advantage of IAB 5G standard for Massive Multiple Input Multiple Output (MIMO) HetNets. Transmit antenna resources are divided among access for MBS users and for providing wireless backhaul for SBS. We develop A Genetic Algorithm (GA) based Transmit Antenna Selection (TAS) scheme and compare with random selection, eigenvalue-based selection and bandwidth portioning. Our analysis show that GA based TAS has the ability to converge to an optimum antenna subset providing better rate coverage. Furthermore, we also signify the performance of TAS based partitioning over bandwidth partitioning and also show user association can also be controlled using number of antennas reserved for access or backhaul.

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Enhanced Transmit-Antenna Selection Schemes for Multiuser Massive MIMO Systems

Wireless Communications and Mobile Computing ◽

10.1155/2017/3463950 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Byung-Jin Lee ◽

Sang-Lim Ju ◽

Nam-il Kim ◽

Kyung-Seok Kim

Keyword(s):

Computational Complexity ◽

Radio Frequency ◽

Spectral Efficiency ◽

Massive Mimo ◽

Mimo Systems ◽

Antenna Selection ◽

Base Station ◽

Base Stations ◽

Transmit Antenna Selection ◽

Selection Scheme

Massive multiple-input multiple-output (MIMO) systems are a core technology designed to achieve the performance objectives defined for 5G wireless communications. They achieve high spectral efficiency, reliability, and diversity gain. However, the many radio frequency chains required in base stations equipped with a high number of transmit antennas imply high hardware costs and computational complexity. Therefore, in this paper, we investigate the use of a transmit-antenna selection scheme, with which the number of required radio frequency chains in the base station can be reduced. This paper proposes two efficient transmit-antenna selection (TAS) schemes designed to consider a trade-off between performance and computational complexity in massive MIMO systems. The spectral efficiency and computational complexity of the proposed schemes are analyzed and compared with existing TAS schemes, showing that the proposed algorithms increase the TAS performance and can be used in practical systems. Additionally, the obtained results enable a better understanding of how TAS affects massive MIMO systems.

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Performance Analysis of Backhaul-Aware User Association in 5G Ultradense Heterogeneous Networks

Wireless Communications and Mobile Computing ◽

10.1155/2021/8879690 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Junpeng Yu ◽

Hongtao Zhang ◽

Yuqing Chen ◽

Yaduan Ruan

Keyword(s):

Heterogeneous Networks ◽

Association Scheme ◽

Coverage Probability ◽

Network Performance ◽

Performance Metrics ◽

Density Ratio ◽

Base Station ◽

Base Stations ◽

User Association ◽

The Impact

In 5G ultradense heterogeneous networks, wireless backhaul, as one of the important base station (BS) resources that affect user services, has attracted more and more attention. However, a user would access to the BS which is the nearest for the user based on the conventional user association scheme, which constrains the network performance improvement due to the limited backhaul capacity. In this paper, using backhaul-aware user association scheme, semiclosed expressions of network performance metrics are derived in ultradense heterogeneous networks, including coverage probability, rate coverage, and network delay. Specifically, all possible access and backhaul links within the user connectable range of BSs and anchor base stations (A-BSs) are considered to minimize the analytical results of outage probability. The outage for the user occurs only when the access link or backhaul link which forms the link combination with the optimal performance is failure. Furthermore, the theoretical analysis and numerical results evaluate the impact of the fraction of A-BSs and the BS-to-user density ratio on network performance metric to seek for a more reasonable deployment of BSs in the practical scenario. The simulation results show that the coverage probability of backhaul-aware user association scheme is improved significantly by about 2× compared to that of the conventional user association scheme when backhaul is constrained.

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A Comparison of Norm Based Antenna Selection and Random Antenna Selection with Regard to Energy Efficiency in Wireless System with Large Number of Users

International Journal of Sensors Wireless Communications and Control ◽

10.2174/2210327909666190319145555 ◽

2020 ◽

Vol 10 (2) ◽

pp. 189-196

Author(s):

Ashu Taneja ◽

Nitin Saluja

Keyword(s):

Energy Efficiency ◽

Mimo Systems ◽

Antenna Selection ◽

Mimo System ◽

Multiple Input Multiple Output ◽

Base Station ◽

Transmit Antenna Selection ◽

Wireless System ◽

Multiple Input ◽

Input Multiple Output

Background: The paper considers the wireless system with large number of users (more than 50 users) and each user is assigned large number of antennas (around 200) at the Base Station (BS). Objective: The challenges associated with the defined system are increased power consumption and high complexity of associated circuitry. The antenna selection is introduced to combat these problems while the usage of linear precoding reduces computational complexity. The literature suggests number of antenna selection techniques based on statistical properties of signal. However, each antenna selection technique suits well to specific number of users. Methods: In this paper, the random antenna selection is compared with norm-based antenna selection. It is analysed that the random antenna selection leads to inefficient spectral efficiency if the number of users are more than 50 in Multi-User Multiple-Input Multiple Output (MU-MIMO) system. Results: The paper proposes the optimization of Energy-Efficiency (EE) with random transmit antenna selection for large number of users in MU-MIMO systems. Conclusion: Also the computation leads to optimization of number of transmit antennas at the BS for energy efficiency. The proposed algorithm results in improvement of the energy efficiency by 27% for more than 50 users.

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Utility-Based Wireless Routing Algorithm for Massive MIMO Heterogeneous Networks

Applied Sciences ◽

10.3390/app10207261 ◽

2020 ◽

Vol 10 (20) ◽

pp. 7261

Author(s):

Wei Zhao ◽

Wen-Hsing Kuo

Keyword(s):

Heterogeneous Networks ◽

Massive Mimo ◽

Routing Algorithm ◽

Multiple Input Multiple Output ◽

Base Station ◽

Base Stations ◽

Small Cells ◽

Multihop Wireless ◽

Wireless Backhaul ◽

Input Multiple Output

With the development of 5G communication, massive multiple input multiple output (MIMO) technology is getting more and more attention. Massive MIMO uses a large amount of simultaneous transmitting and receiving antennas to reduce power consumption and raise the level of transmission quality. Meanwhile, the diversification of user equipment (UE) in the 5G environment also makes heterogeneous networks (HetNets) more prevalent. HetNets allow UE of different network standards to access small cells, while the base stations of small cells access a macro base station (BS) to form a multihop wireless heterogeneous backhaul network. However, how to effectively combine these two technologies by efficiently allocating the antennas of each BS during the route construction process of heterogeneous wireless backhaul networks is still an important issue that is yet to be solved. In this paper, we propose an algorithm called preallocated sequential routing (PSR). Based on the links’ channel conditions and the available antennas and location of BSs, it builds a wireless heterogeneous network backhaul topology and adjusts each link’s transmitting and receiving antennas to maximize total utility. Simulation results showed that the proposed algorithm significantly improved the overall utility and the utility of the outer area of heterogeneous networks.

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Exploiting Joint Base Station Equipped Multiple Antenna and Full-Duplex D2D Users in Power Domain Division Based Multiple Access Networks

Sensors ◽

10.3390/s19112475 ◽

2019 ◽

Vol 19 (11) ◽

pp. 2475 ◽

Cited By ~ 8

Author(s):

Dinh-Thuan Do ◽

Minh-Sang Van Nguyen ◽

Thi-Anh Hoang ◽

Byung Moo Lee

Keyword(s):

Multiple Access ◽

Antenna Selection ◽

Base Station ◽

Base Stations ◽

Full Duplex ◽

Mobile Users ◽

Multiple Antenna ◽

Transmit Antenna Selection ◽

Single Output ◽

Power Domain

In this paper, we investigate power domain division-based multiple access (PDMA) to support the base stations (BS) equipped with multiple antennas to serve mobile users. Such a system deploys multiple input single output (MISO)-based wireless transmission and a full-duplex (FD) scheme. Furthermore, such MISO PDMA system consists of BS employing transmit antenna selection to reduce complexity in signal processing at the receivers. We distinguish two kinds of mobile users, device-to-device (D2D) users and traditional users. In such MISO PDMA, there exists a trade-off between outage performance of each PDMA user and power allocation factors. Since the implementation of the FD scheme at PDMA users, bandwidth efficiency will be enhanced despite the existence of self-interference related to such FD. In particular, exact expressions of outage probability are derived to exhibit system performance with respect to D2D users. Finally, valuable results from the simulated parameters together with the analytical results show that MISO PDMA can improve its performance by increasing the number of transmit antennas at the BS.

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Robust Transmit Antenna Design for Performance Improvement of Cell-Edge Users: Approach of NOMA and Outage/Ergodic Capacity Analysis

Sensors ◽

10.3390/s19224907 ◽

2019 ◽

Vol 19 (22) ◽

pp. 4907 ◽

Cited By ~ 2

Author(s):

Dinh-Thuan Do ◽

Chi-Bao Le ◽

Byung Moo Lee

Keyword(s):

Closed Form ◽

Performance Improvement ◽

Antenna Selection ◽

Access Point ◽

Ergodic Capacity ◽

Base Station ◽

Base Stations ◽

Closed Form Expression ◽

Transmit Antenna Selection ◽

Outage Performance

In this investigation, a wireless sensor network using a non-orthogonal multiple access (NOMA) system is considered in two scenarios related to the number of serving access point/base stations, where two policies provide system performance improvement in two sensors (the near user and the far user). To improve performance efficiency, two robust transmit antenna strategies are designed related to the access point/base station (BS), namely (i) Transmit Antenna Selection (TAS) mode and (ii) two base station (TBS) approach to simultaneously serve NOMA users. First, the TAS scheme is implemented to provide suboptimal outage performance for such NOMA, in which BS equipped at least two antennas while NOMA users are equippeda single antenna. Secondly, the TBS scheme is conducted to enhance the outage performance, especially considering priority evaluation for the far user in user pairs. As an important result, such far users in two proposed schemes are studied by introducing the exact closed-form expression to examine outage behavior. Accordingly, the closed-form expressions regarding ergodic capacity can be further obtained. To corroborate the exactness of these metrics, Monte Carlo simulation is performed. In addition, the proposed schemes exhibit various performance evaluations accompanied by different related parameters such as power allocation factors, the number of transmit antenna, and transmit signal-to-noise ratio (SNR).

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Interference Cancellation Based Spectrum Sharing for Massive MIMO Communication Systems

Sensors ◽

10.3390/s21113584 ◽

2021 ◽

Vol 21 (11) ◽

pp. 3584

Author(s):

Milembolo Miantezila Junior ◽

Bin Guo ◽

Chenjie Zhang ◽

Xuemei Bai

Keyword(s):

Interference Cancellation ◽

Communication Systems ◽

Spectrum Sharing ◽

Null Space ◽

Base Station ◽

Base Stations ◽

Small Cells ◽

Data Traffic ◽

New Approach ◽

Lte Advanced

Cellular network operators are predicting an increase in space of more than 200 percent to carry the move and tremendous increase of total users in data traffic. The growing of investments in infrastructure such as a large number of small cells, particularly the technologies such as LTE-Advanced and 6G Technology, can assist in mitigating this challenge moderately. In this paper, we suggest a projection study in spectrum sharing of radar multi-input and multi-output, and mobile LTE multi-input multi-output communication systems near m base stations (BS). The radar multi-input multi-output and mobile LTE communication systems split different interference channels. The new approach based on radar projection signal detection has been proposed for free interference disturbance channel with radar multi-input multi-output and mobile LTE multi-input multi-output by using a new proposed interference cancellation algorithm. We chose the channel of interference with the best free channel, and the detected signal of radar was projected to null space. The goal is to remove all interferences from the radar multi-input multi-output and to cancel any disturbance sources from a chosen mobile Communication Base Station. The experimental results showed that the new approach performs very well and can optimize Spectrum Access.

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Study of 5G-NR-MIMO Links in the Presence of an Interferer

Electronics ◽

10.3390/electronics10060732 ◽

2021 ◽

Vol 10 (6) ◽

pp. 732

Author(s):

Avner Elgam ◽

Yael Balal ◽

Yosef Pinhasi

Keyword(s):

Mobile Networks ◽

Communication Systems ◽

Multiple Input Multiple Output ◽

Local Area ◽

Maximum Energy ◽

Base Station ◽

Small Cells ◽

Diversity Coding ◽

Shift Keying ◽

Input Multiple Output

Many communication systems are based on the Multiple Input, Multiple Output (MIMO) scheme, and Orthogonal Space–time Block Transmit diversity Coding (OSTBC), combined with Maximal Ratio Receive Combining (MRRC), to create an optimal diversity system. A system with optimal diversity fixes and optimizes the channel’s effects under multi-path and Rayleigh fading with maximum energy efficiency; however, the challenge does not end with dealing with the channel destruction of the multi-path impacts. Susceptibility to interference is a significant vulnerability in future wireless mobile networks. The 5th Generation New Radio (5G-NR) technologies bring hundreds of small cells and pieces of User Equipment (UE) per indoor or outdoor local area scenario under a specific Long Term Evolution (LTE)-based station (e-NodeB), or under 5G-NR base-station (g-NodeB). It is necessary to study issues that deal with many interference signals, and smart jammers from advanced communication equipment cause deterioration in the links between the UE, the small cells, and the NodeB. In this paper, we study and present the significant impact and performances of 2×2 Alamouti Phase-Shift Keying (PSK) modulation techniques in the presence of an interferer and a smart jammer. The destructive effects affecting the MIMO array and the advanced diversity technique without closed-loop MIMO are analyzed. The performance is evaluated in terms of Bit Error Rate (BER) vs. Signal to Interference Ratio (SIR). In addition, we proved the impairment of the orthogonal spectrum assumption mathematically.

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Analysis of the Effect of Tilting Antenna on the Coverage Area of ??the 4G LTE Network (Case Study of Trenggalek District)

Jurnal Jartel Jurnal Jaringan Telekomunikasi ◽

10.33795/jartel.v9i4.154 ◽

2019 ◽

Vol 9 (4) ◽

pp. 43-48

Author(s):

Rizal Aji Istantowi

Keyword(s):

Base Station ◽

Base Stations ◽

Optimal Conditions ◽

Coverage Area ◽

Lte Networks ◽

Lte Network ◽

Big Cities ◽

4G Lte ◽

4G Lte Networks

4G LTE networks in big cities are already well available. Meanwhile, on small to medium-sized cities, the 4G LTE network is not evenly distributed and maximized. This study chooses the variable tilting antenna to the coverage area, because in sending information from a base station using an antenna. The average RSRP value (dBm) of the existing base station in the calculation with a distance of 200 m is -122.90 dBm, a distance of 500 m is -136.79 dBm, and a distance of 1000 m -147.30 dBm. Meanwhile, in the simulation with a distance of 200 m of -108.22 dBm, a distance of 500 m of -121.81 dBm, and a distance of 1000 m of -132.69 dBm. The coverage area value of the existing base station in the calculation is 5.29%, while in the simulation it is 11.18%. The average RSRP value (dBm) at optimal conditions for calculations at a distance of 200 m is -80.13 dBm, at a distance of 500 m is -94.03 dBm and at a distance of 1000 m is -104.56 dBm. Meanwhile, the simulation at a distance of 200 m is -98.09 dBm, at a distance of 500 m is -112.79 dBm and at a distance of 1000 m is -123.31 dBm. The value of the coverage area for the calculation is 20.32%, while for the simulation it is 15.01%. The current need for base stations in Trenggalek District that has been met is 68%.

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A Monte Carlo Analysis of Actual Maximum Exposure From a 5G Millimeter-Wave Base Station Antenna for EMF Compliance Assessments

Frontiers in Public Health ◽

10.3389/fpubh.2021.777759 ◽

2022 ◽

Vol 9 ◽

Author(s):

Bo Xu ◽

David Anguiano Sanjurjo ◽

Davide Colombi ◽

Christer Törnevik

Keyword(s):

Monte Carlo ◽

Millimeter Wave ◽

Near Field ◽

Multiple Input Multiple Output ◽

Monte Carlo Analysis ◽

Base Station ◽

Base Stations ◽

Far Field ◽

Wave Radio ◽

Maximum Exposure

International radio frequency (RF) electromagnetic field (EMF) exposure assessment standards and regulatory bodies have developed methods and specified requirements to assess the actual maximum RF EMF exposure from radio base stations enabling massive multiple-input multiple-output (MIMO) and beamforming. Such techniques are based on the applications of power reduction factors (PRFs), which lead to more realistic, albeit conservative, exposure assessments. In this study, the actual maximum EMF exposure and the corresponding PRFs are computed for a millimeter-wave radio base station array antenna. The computed incident power densities based on near-field and far-field approaches are derived using a Monte Carlo analysis. The results show that the actual maximum exposure is well below the theoretical maximum, and the PRFs similar to those applicable for massive MIMO radio base stations operating below 6 GHz are also applicable for millimeter-wave frequencies. Despite the very low power levels that currently characterize millimeter-wave radio base stations, using the far-field approach can also guarantee the conservativeness of the PRFs used to assess the actual maximum exposure close to the antenna.

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