The impact of base station antennas configuration on the performance of millimetre wave 5G networks

Massive Multi-Input and Multi-Output (MIMO) antenna system provides unlimited capacity by the spatial multiplexing and array gain. Since the data rate has been limited by the coherence interference due to pilot contamination (PC). In this paper, we propose transmit combine and precoding schemes to achieve asymptotic capacity in multi-cell scenario, when the number of base station antennas tends to infinity. The impact of spatial channel correlation on channel capacity is explored by considering the co-variance matrices of the user –terminals (UT)s .To do this, we presented linear processing schemes such as MMSE,MRC, and ZF.Where MMSE achieves high capacity in the presence of large-scale fading and PC. Since the diagonals of the channel covariance matrices were designed with non- zero Eigen values and linearly independent. The results outperform and obtain asymptotic limit, when the co-variance of UTs are linearly independent. The results were simulated by using MATLAB 2018b.

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Multi Beam Dielectric Lens Antenna for 5G Base Station

Sensors ◽

10.3390/s20205849 ◽

2020 ◽

Vol 20 (20) ◽

pp. 5849 ◽

Cited By ~ 1

Author(s):

Farizah Ansarudin ◽

Tharek Abd Rahman ◽

Yoshihide Yamada ◽

Nurul Huda Abd Rahman ◽

Kamilia Kamardin

Keyword(s):

Radiation Pattern ◽

Base Station ◽

Base Stations ◽

Beam Radiation ◽

Lens Antenna ◽

Millimetre Wave ◽

Small Curvature ◽

Lens Antennas ◽

Base Station Antennas ◽

Dielectric Lens

In the 5G mobile system, new features such as millimetre wave operation, small cell size and multi beam are requested at base stations. At millimetre wave, the base station antennas become very small in size, which is about 30 cm; thus, dielectric lens antennas that have excellent multi beam radiation pattern performance are suitable candidates. For base station application, the lens antennas with small thickness and small curvature are requested for light weight and ease of installation. In this paper, a new lens shaping method for thin and small lens curvature is proposed. In order to develop the thin lens antenna, comparisons of antenna structures with conventional aperture distribution lens and Abbe’s sine lens are made. Moreover, multi beam radiation pattern of three types of lenses are compared. As a result, the thin and small curvature of the proposed lens and an excellent multi beam radiation pattern are ensured.

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Energy-Efficient Packet Forwarding Scheme Based on Fuzzy Decision-Making in Underwater Sensor Networks

Sensors ◽

10.3390/s21134368 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4368

Author(s):

Jitander Kumar Pabani ◽

Miguel-Ángel Luque-Nieto ◽

Waheeduddin Hyder ◽

Pablo Otero

Keyword(s):

Energy Consumption ◽

Sensor Networks ◽

Energy Efficient ◽

Real Life ◽

Base Station ◽

Fuzzy Decision Making ◽

Underwater Sensor Networks ◽

Packet Forwarding ◽

Node Number ◽

The Impact

Underwater Wireless Sensor Networks (UWSNs) are subjected to a multitude of real-life challenges. Maintaining adequate power consumption is one of the critical ones, for obvious reasons. This includes proper energy consumption due to nodes close to and far from the sink node (gateway), which affect the overall energy efficiency of the system. These wireless sensors gather and route the data to the onshore base station through the gateway at the sea surface. However, finding an optimum and efficient path from the source node to the gateway is a challenging task. The common reasons for the loss of energy in existing routing protocols for underwater are (1) a node shut down due to battery drainage, (2) packet loss or packet collision which causes re-transmission and hence affects the performance of the system, and (3) inappropriate selection of sensor node for forwarding data. To address these issues, an energy efficient packet forwarding scheme using fuzzy logic is proposed in this work. The proposed protocol uses three metrics: number of hops to reach the gateway node, number of neighbors (in the transmission range of a node) and the distance (or its equivalent received signal strength indicator, RSSI) in a 3D UWSN architecture. In addition, the performance of the system is also tested with adaptive and non-adaptive transmission ranges and scalable number of nodes to see the impact on energy consumption and number of hops. Simulation results show that the proposed protocol performs better than other existing techniques or in terms of parameters used in this scheme.

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Synchronization in 5G networks: a hybrid Bayesian approach toward clock offset/skew estimation and its impact on localization

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-021-01963-x ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Meysam Goodarzi ◽

Darko Cvetkovski ◽

Nebojsa Maletic ◽

Jesús Gutiérrez ◽

Eckhard Grass

Keyword(s):

Bayesian Approach ◽

Large Scale ◽

Hybrid Approach ◽

Position Estimation ◽

5G Networks ◽

Clock Skew ◽

Depth Analysis ◽

The Impact ◽

Mean Square Errors ◽

Clock Offset

AbstractClock synchronization has always been a major challenge when designing wireless networks. This work focuses on tackling the time synchronization problem in 5G networks by adopting a hybrid Bayesian approach for clock offset and skew estimation. Furthermore, we provide an in-depth analysis of the impact of the proposed approach on a synchronization-sensitive service, i.e., localization. Specifically, we expose the substantial benefit of belief propagation (BP) running on factor graphs (FGs) in achieving precise network-wide synchronization. Moreover, we take advantage of Bayesian recursive filtering (BRF) to mitigate the time-stamping error in pairwise synchronization. Finally, we reveal the merit of hybrid synchronization by dividing a large-scale network into local synchronization domains and applying the most suitable synchronization algorithm (BP- or BRF-based) on each domain. The performance of the hybrid approach is then evaluated in terms of the root mean square errors (RMSEs) of the clock offset, clock skew, and the position estimation. According to the simulations, in spite of the simplifications in the hybrid approach, RMSEs of clock offset, clock skew, and position estimation remain below 10 ns, 1 ppm, and 1.5 m, respectively.

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