scholarly journals Hybrid Beamforming for Millimeter-Wave Heterogeneous Networks

Electronics ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 133 ◽  
Author(s):  
Mostafa Hefnawi
Keyword(s):  
Millimeter Wave ◽  
Heterogeneous Networks ◽  
Antenna Arrays ◽  
Large Scale ◽  
Network Capacity ◽  
Base Station ◽  
Antenna Element ◽  
Digital Beamforming ◽  
Hybrid Beamforming ◽  
Cell Base

Heterogeneous networks (HetNets) employing massive multiple-input multiple-output (MIMO) and millimeter-wave (mmWave) technologies have emerged as a promising solution to enhance the network capacity and coverage of next-generation 5G cellular networks. However, the use of traditional fully-digital MIMO beamforming methods, which require one radio frequency (RF) chain per antenna element, is not practical for large-scale antenna arrays, due to the high cost and high power consumption. To reduce the number of RF chains, hybrid analog and digital beamforming has been proposed as an alternative structure. In this paper, therefore, we consider a HetNet formed with one macro-cell base station (MBS) and multiple small-cell base stations (SBSs) equipped with large-scale antenna arrays that employ hybrid analog and digital beamforming. The analog beamforming weight vectors of the MBS and the SBSs correspond to the the best-fixed multi-beams obtained by eigendecomposition schemes. On the other hand, digital beamforming weights are optimized to maximize the receive signal-to-interference-plus-noise ratio (SINR) of the effective channels consisting of the cascade of the analog beamforming weights and the actual channel. The performance is evaluated in terms of the beampatterns and the ergodic channel capacity and shows that the proposed hybrid beamforming scheme achieves near-optimal performance with only four RF chains while requiring considerably less computational complexity.

scholarly journals Robust Hybrid Beamforming Scheme for Millimeter-Wave Massive-MIMO 5G Wireless Networks

Symmetry ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1424 ◽  
Author(s):  
Saleem Latteef Mohammed ◽  
Mohammed H. Alsharif ◽  
Sadik Kamel Gharghan ◽  
Imran Khan ◽  
Mahmoud Albreem
Keyword(s):  
Wireless Networks ◽  
Millimeter Wave ◽  
Massive Mimo ◽  
Large Scale ◽  
Minimum Mean Square Error ◽  
Multiple Input Multiple Output ◽  
Low Complexity ◽  
Network Capacity ◽  
System Throughput ◽  
Hybrid Beamforming

Wireless networks employing millimeter-wave (mmWave) and Massive Multiple-Input Multiple-Output (MIMO) technologies are a key approach to boost network capacity, coverage, and quality of service (QoS) for future communications. They deploy symmetric antennas on a large scale in order to enhance the system throughput and data rate. However, increasing the number of antennas and Radio Frequency (RF) chains results in high computational complexity and more energy requirements. Therefore, to solve these problems, this paper proposes a low-complexity hybrid beamforming scheme for mmWave Massive-MIMO 5G wireless networks. The proposed algorithm is on the basis of alternating the minimum mean square error (Alt-MMSE) hybrid beamforming technique in which the orthogonal properties of the digital matrix were designed, and then the MSE of the transmitted and received signal was reduced. The phase of the analog matrix was obtained from the updated digital matrix. Simulation results showed that the proposed hybrid beamforming algorithm had better performance than existing state-of-the-art algorithms, and similar performance with the optimal digital precoding algorithm.

scholarly journals Performance analysis of multi user massive MIMO hybrid beamforming systems at millimeter wave frequency bands

2021 ◽  
Author(s):  
Ravilla Dilli
Keyword(s):  
Wireless Networks ◽  
Millimeter Wave ◽  
Antenna Arrays ◽  
Data Streams ◽  
Research Work ◽  
Path Loss ◽  
Base Station ◽  
Frequency Bands ◽  
Hybrid Beamforming ◽  
Key Enabling Technologies

AbstractMillimeter-wave (mmWave) and massive multi-input–multi-output (mMIMO) communications are the most key enabling technologies for next generation wireless networks to have large available spectrum and throughput. mMIMO is a promising technique for increasing the spectral efficiency of wireless networks, by deploying large antenna arrays at the base station (BS) and perform coherent transceiver processing. Implementation of mMIMO systems at mmWave frequencies resolve the issue of high path-loss by providing higher antenna gains. The motivation for this research work is that mmWave and mMIMO operations will be much more popular in 5G NR, considering the wide deployment of mMIMO in major frequency bands as per 3rd generation partnership project. In this paper, a downlink multi-user mMIMO (MU-mMIMO) hybrid beamforming communication system is designed with multiple independent data streams per user and accurate channel state information. It emphasizes the hybrid precoding at transmitter and combining at receiver of a mmWave MU-mMIMO hybrid beamforming system. Results of this research work give the tradeoff between multiple data streams per user and required number of BS antennas. It strongly recommends for higher number of parallel data streams per user in a mmWave MU-mMIMO systems to achieve higher order throughputs.

scholarly journals Research on 5G-Oriented Wireless Sensor Array of Millimeter Hybrid Beam Sensing Terminal

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Shengli Yan
Keyword(s):  
Channel Estimation ◽  
Millimeter Wave ◽  
Rapid Development ◽  
Mobile Internet ◽  
Projection Algorithm ◽  
Wireless Sensor ◽  
Digital Beamforming ◽  
Hybrid Beam ◽  
Hybrid Beamforming ◽  
Internet Of Things Technology

With the rapid development of information technology, facing the problems and new challenges brought by mobile Internet and Internet of things technology, as one of the key technologies of 5G, millimeter-wave mobile communication (28/38/60/70 GHz) which can realize gigabit (GB/s, or even higher) data transmission rate has also attracted extensive attention of wireless researchers all over the world, it has quickly become a research hotspot in the field of wireless communication. In the millimeter-wave massive MIMO downlink wireless sensor system, a block diagonal beamforming algorithm based on the approximate inverse of Neumann series is improved to obtain complete digital beamforming. Then, when designing hybrid beamforming, channel estimation and high-dimensional singular value decomposition are required for traditional analog and digital hybrid beamforming. A low complexity hybrid beamforming scheme is designed. An improved gradient projection algorithm is proposed in the design of analog beamforming, which can solve the problem of high computational complexity and less damage to guarantee and rate. Simulation results show that the hybrid beam terminal of the sensor reduces the number of RF links required for full digital beamforming and is as close to the spectral efficiency performance of full digital beamforming as possible. The results show that the performance of the designed hybrid beamforming scheme can still be close to that of the pure digital beamforming scheme without involving channel estimation and SVD decomposition.

LTCC slot array antenna for 5G application

2019 ◽  
Vol 2019 (1) ◽  
pp. 000238-000242
Author(s):  
Hiroyuki Takahashi ◽  
Satoshi Hirano ◽  
Daisuke Yamashita
Keyword(s):  
Mobile Device ◽  
Beam Steering ◽  
Base Station ◽  
Small Cell ◽  
Array Antenna ◽  
Antenna Element ◽  
Beam Angle ◽  
Antenna Size ◽  
Antenna Module ◽  
Cell Base

Abstract We develop the antenna module substrate which is broadband and large gain using an LTCC technology in a 28GHz band in this study. We used LTCC materials (dielectric constant 5.8, Dielectric loss 0.002@28GHz) which we developed for materials originally. First of all, we confirmed ability of slot array antenna made by LTCC for 5G application to get broadband property. The structure of designed array antenna became 40mm × 3.2mm × t1.6mm. We confirmed that this antenna has wider bandwidth (2.2GHz) and higher gain (6dBi). But this antenna size is too large for applying mobile device. Therefore we redesigned to reduce antenna size without specification degradation. The structure of redesigned antenna element becomes basically 4.8mm × 6.7mm × t1.0mm. This antenna has wider bandwidth (2.7GHz). The gains are more than 5dBi for the characteristic of this element in a band. Assume this antenna a fabric; 2 × 2 (4 elements: for mobile device) and 4 × 4 (16 elements: for small cell base station) we make an array antenna for Small cell base station and for mobile device. We will evaluate a beam steering examination with emission properties (gain, beam angle).

scholarly journals Cell Outage Detection and Compensation in Two-Tier Heterogeneous Networks

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Wenqian Xue ◽  
Hengzhi Zhang ◽  
Yong Li ◽  
Dong Liang ◽  
Mugen Peng
Keyword(s):  
Heterogeneous Networks ◽  
Nearest Neighbor ◽  
Network Capacity ◽  
Vertical Handover ◽  
Base Station ◽  
Data Traffic ◽  
Traffic Demand ◽  
Planning Optimization ◽  
And Performance ◽  
Optimizing Algorithm

Heterogeneous networks (HetNets) can increase network capacity through complementing the macro-base-station with low-power nodes, in response to the ongoing exponential growth in data traffic demand. While, unprecedented challenges exist in the planning, optimization, and maintenance in HetNets, especially activities such as cell outage detection and mitigation are labor-intensive and costly. One potential solution to address these issues is to introduce the extensively attracted self-organizing network (SON). This paper is mainly devoted to cell outage detection and compensation methods in two-tier HetNets where macrocell and picocells are coexisted. AK-nearest neighbor (KNN) classification algorithm is employed to detect the cell outage automatically. Consider the breakdown picocell can reload its degraded service to the overlapped macrocell via vertical handover; only the breakdown macrocell executes the performance compensation. Power adjustment on each resource block is carried out via Lagrange optimizing algorithm to compensate the breakdown cell. Through intensive numerical experiments, with the help of our proposal, the outage cells can be successfully detected and performance gain for the outage macrocell can reach 91.4% withα=1/3.

scholarly journals Analytical Blind Beamforming for a Multi-Antenna UAV Base-Station Receiver in Millimeter-Wave Bands

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6561
Author(s):  
Pingchuan Liu ◽  
Kuangang Fan ◽  
Yuhang Chen
Keyword(s):  
Channel Estimation ◽  
Millimeter Wave ◽  
Antenna Arrays ◽  
Base Station ◽  
Base Stations ◽  
Signal Recovery ◽  
Constant Modulus ◽  
Signal Space ◽  
Target User ◽  
Blind Beamforming

Over the last decade, unmanned aerial vehicles (UAVs) with antenna arrays have usually been employed for the enhancement of wireless communication in millimeter-wave bands. They are commonly used as aerial base stations and relay platforms in order to serve multiple users. Many beamforming methods for improving communication quality based on channel estimation have been proposed. However, these methods can be resource-intensive due to the complexity of channel estimation in practice. Thus, in this paper, we formulate an MIMO blind beamforming problem at the receivers for UAV-assisted communications in which channel estimation is omitted in order to save communication resources. We introduce one analytical method, which is called the analytical constant modulus algorithm (ACMA), in order to perform blind beamforming at the UAV base station; this relies only on data received by the antenna. The feature of the constant modulus (CM) is employed to restrict the target user signals. Algebraic operations, such as singular value decomposition (SVD), are applied to separate the user signal space from other interferences. The number of users in the region served by the UAV can be detected by exploring information in the measured data. We seek solutions that are expressible as one Kronecker product structure in the signal space; then, the beamformers that correspond to each user can be successfully estimated. The simulation results show that, by using this analytically derived blind method, the system can achieve good signal recovery accuracy, a reasonable system sum rate, and acceptable complexity.

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