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Wyszukujesz frazę "5G" wg kryterium: Wszystkie pola


Tytuł:
MIMO Beam Selection in 5G Using Neural Networks
Autorzy:
Ruseckas, Julius
Molis, Gediminas
Bogucka, Hanna
Powiązania:
https://bibliotekanauki.pl/articles/2055220.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
5G
context information
MIMO beam orientation
machine learning
neural networks
Opis:
In this paper, we consider cell-discovery problem in 5G millimeter-wave (mmWave) communication systems using multiple input, multiple output (MIMO) beam-forming technique. Specifically, we aim at the proper beam selection method using context-awareness of the user-equipment to reduce latency in beam/cell identification. Due to high path-loss in mmWave systems, beam-forming technique is extensively used to increase Signal-to-Noise Ratio (SNR). When seeking to increase user discovery distance, narrow beam must be formed. Thus, a number of possible beam orientations and consequently time needed for the discovery increases significantly when random scanning approach is used. The idea presented here is to reduce latency by employing artificial intelligence (AI) or machine learning (ML) algorithms to guess the best beam orientation using context information from the Global Navigation Satellite System (GNSS), lidars and cameras, and use the knowledge to swiftly initiate communication with the base station. To this end, here, we propose a simple neural network to predict beam orientation from GNSS and lidar data. Results show that using only GNSS data one can get acceptable performance for practical applications. This finding can be useful for user devices with limited processing power.
Źródło:
International Journal of Electronics and Telecommunications; 2021, 67, 4; 693--698
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Centralized Spectrum Sharing and Coordination Between Terrestrial and Aerial Base Stations of 3GPP-Based 5G Networks
Autorzy:
Bechta, Kamil
Powiązania:
https://bibliotekanauki.pl/articles/1844695.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
5G
spectrum sharing
unmanned aerial vehicle
Opis:
The objective of this paper is to estimate performance of a new approach for spectrum sharing and coordination between terrestrial base stations (BS) and On-board radio access nodes (UxNB) carried by Unmanned Aerial Vehicles (UAV). This approach employs an artificial intelligence (AI) based algorithm implemented in a centralized controller. According to the assessment based on the latest specifications of 3rd Generation Partnership Project (3GPP) the newly defined Unmanned Aerial System Traffic Management (UTM) is feasible to implement and utilize an algorithm for dynamic and efficient distribution of available radio resources between all radio nodes involved in process of optimization. An example of proprietary algorithm has been described, which is based on the principles of Kohonen neural networks. The algorithm has been used in simulation scenario to illustrate the performance of the novel approach of centralized radio channels allocation between terrestrial BSs and UxNBs deployed in 3GPP-defined rural macro (RMa) environment. Simulation results indicate that at least 85% of simulated downlink (DL) transmissions are gaining additional channel bandwidth if presented algorithm is used for spectrum distribution between terrestrial BSs and UxNBs instead of baseline soft frequency re-use (SFR) approach.
Źródło:
International Journal of Electronics and Telecommunications; 2021, 67, 2; 301-308
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Per Sub-band Tone Reservation Scheme for Universal Filtered Multi-Carrier Signal
Autorzy:
Mounira, Laabidi
Ridha, Bouallegue
Powiązania:
https://bibliotekanauki.pl/articles/27311943.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
UFMC
PAPR
PSTR
Fifth generation (5G)
Opis:
Fifth generation (5G) applications like Internet of Things (IoT), Enhanced Mobile Broadband (eMBB), Cognitive Radios (CR), Vehicle to Vehicle (V2V) and Machine to Machine (M2M) communication put new demands on the network in terms of low latency, ultra-reliable communication and efficiency when transmitting very small bursts. One new contender that makes its appearance recently is the Universal Filtered Multi- Carrier (UFMC). UFMC is a potential candidate to meet the requirements of 5G upcoming applications. This related waveform encounters the peak-to-average power ratio (PAPR) issue arising from the usage of multi-carrier transmission. In this investigation, two PAPR reduction techniques, called Per Subband Tone Reservation (PSTR) scheme to alleviate PAPR in UFMC systems are suggested. The first one is a pre-filtering PSTR scheme that uses the least squares approximation (LSA) algorithm to calculate the optimization factor(μ) and the second one is a post-filtering method. The concept of this proposal lies on the use of peaks reductions Tone to carry the correctional signal that reduces the high peaks of each sub-band individually. To shed light on UFMC as a potential waveform for 5G upcoming application, a comparison with OFDM modulation is done.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 3; 545--552
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interference in Multi-beam Antenna System of 5G Network
Autorzy:
Kelner, Jan M.
Ziółkowski, Cezary
Powiązania:
https://bibliotekanauki.pl/articles/226986.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
systems and networks
interference
multi-elliptical propagation model
multi-beam antenna system
simulation studies
massive MIMO
Opis:
Massive multiple-input-multiple-output (MIMO) and beamforming are key technologies, which significantly influence on increasing effectiveness of emerging fifth-generation (5G) wireless communication systems, especially mobile-cellular networks. In this case, the increasing effectiveness is understood mainly as the growth of network capacity resulting from better diversification of radio resources due to their spatial multiplexing in macro- and micro-cells. However, using the narrow beams in lieu of the hitherto used cell-sector brings occurring interference between the neighboring beams in the massive-MIMO antenna system, especially, when they utilize the same frequency channel. An analysis of this effect is the aim of this paper. In this case, it is based on simulation studies, where a multi-elliptical propagation model and standard 3GPP model are used. We present the impact of direction and width of the neighboring beams of 5G new radio gNodeB base station equipped with the multi-beam antenna system on the interference level between these beams. The simulations are carried out for line-of-sight (LOS) and non-LOS conditions of a typical urban environment.
Źródło:
International Journal of Electronics and Telecommunications; 2020, 66, 1; 17-23
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Propagation and Network Analysis for a Dipole Based Massive Mimo Antenna for 5G Base Stations
Autorzy:
Pushpa, Anita Jones Mary
Chrysolite, Samuelraj
Powiązania:
https://bibliotekanauki.pl/articles/2124749.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
5G antenna
massive MIMO
dipole array
maximum gain
Opis:
In today’s fast-paced world, where everyone/everything is moving towards an online platform, the need to provide high-speed data to all is inevitable. Hence, introducing the emerging 5G technology with orthogonal frequency division multiplexing integrated with massive MIMO technology is the need of the hour. A 640 port Massive MIMO (m-MIMO) antenna with high evenly spread gain and very low delay, along with a practically possible data rate operating in the mm waveband, is proposed for a 5G base station. The individual antenna element consists of a dipole (λ=0.5cm) designed to operate at 57GHz. Placing the cylindrical MIMO antenna array (8x20) facing the four directions forming the m-MIMO antenna (160x4) at the height of 3m from ground level for simulation. Achievement of a maximum gain of 23.14dBi (θ=90▫) and a minimum data rate of 1.44Gbps with -10dB bandwidth of 2.1GHz (256-QAM) approximately a distance of 478m from the 5G Base station. The m-MIMO structure gives an Envelope Correlation Coefficient of 0.015. The propagation analysis is carried out to substantiate the performance of the proposed system based on field strength and received power. Network Analysis for better reception performance is carried out by changing the antenna height placement, altering the down tilt of the antenna array, and sweeping the polarization angle of the antenna array.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 3; 511--517
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Energy Efficiency Optimization by Spectral Efficiency Maximization in 5G Networks
Autorzy:
Krasniqi, B.
Rexha, B.
Maloku, B.
Powiązania:
https://bibliotekanauki.pl/articles/226636.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
energy efficiency
5G
radio resources
power allocation
optimization convexity
Opis:
Energy and spectral efficiency are the main challenges in 5th generation of mobile cellular networks. In this paper, we propose an optimization algorithm to optimize the energy efficiency by maximizing the spectral efficiency. Our simulation results show a significant increase in terms of spectral efficiency as well as energy efficiency whenever the mobile user is connected to a low power indoor base station. By applying the proposed algorithm, we show the network performance improvements up to 9 bit/s/Hz in spectral efficiency and 20 Gbit/Joule increase in energy efficiency for the mobile user served by the indoor base station rather than by the outdoor base station.
Źródło:
International Journal of Electronics and Telecommunications; 2018, 64, 4; 497-503
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Most Suitable 5G Simulator Scenarios for Lab as a Service (LaaS) in Higher Education
Autorzy:
Putri, Hasanah
Novanana, Sinta
Powiązania:
https://bibliotekanauki.pl/articles/27311951.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
5G
software
LaaS
higher education laboratory
real network experience
Opis:
The 5G System is being developed and enhanced to provide unparalleled connectivity to connect everyone and everything, everywhere. 5G technology use cases depicts the prospects of 5G network model to revolutionize Industry and Education is not an exception . To catch up with the latest technology in the higher education environment there’s a need to have 5G Lab as a Service (LaaS) in education to simulate the real network experience. The software is the key to this generation as the virtualization, modularity and abstraction become more popular in the implementation and that the cloud computing is nowadays becoming the trend of technology. This paper presents a software selection between free5gc, magma and open5gs program. The 5G lab located in Jakarta Indonesia has the ability where in physical and virtual resources can be accessed and managed from any location in the world. Free5gc opensource software solution is the most suitable software which can be used as LaaS in Higher Education laboratory. With a LaaS, we can configuration, connection, and troubleshoot 5G infrastructure including radio access networks, core networks, and transportation networks.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 4; 639--644
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Propagation Models at 5G Network and Effects of SAR on Human Brain
Autorzy:
Al-Aamri, Nawal
Nadir, Zia
Bait-Suwailam, Mohammed
Al-Lawati, Hassan
Powiązania:
https://bibliotekanauki.pl/articles/2074140.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
pathloss
prediction
5G
RMSE
CI model
ABG model
SAR
Opis:
Nowadays, the world is turning into technology, fast internet and high signal quality. To ensure high signal quality, the network planners have to predict the pathloss and signal strength of the transmitted signal at specific distances in the design stage. The aim of this research is to provide a generalized pathloss model to suit the urban area in Muscat Governorate in the Sultanate of Oman. The research covers 5G network pathloss in the Muttrah Business District (MBD) area. It includes Close In (CI) model and Alpha Beta Gamma (ABG) model with 3.45GHz. The results of 5G models were compared with real experimental data in MBD by calculating Root Mean Square Error RMSE. Other cells at MBD area were used for reverification. To validate the modified pathloss models of 5G, they were applied at different cells in Alkhoud area. Furthermore, this paper also deals the effect of Specific Absorption Rate (SAR) on the human brain for ensuring safety due to close proximity to cell towers. The SAR values were calculated indirectly from the electric field strength of different antennas. Calculated results were compared with the international standards defined limits on the human brain.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 2; 343--349
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of C-shape Slotted MSPA for 5G Sub Band Applications on Three Different Substrates
Autorzy:
Nagaraju, P
Sachina, D.H
Khan, Imran
Kumaraswamy, H.V
Sudhindra, K. R.
Powiązania:
https://bibliotekanauki.pl/articles/2200694.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
C-shape
RT Duroid
Taconic (TLC)
FR4
5G
Opis:
A comparative analysis of a compact planar Square patch Microstrip Multiband antenna on three different substrates is proposed. The proposed design has a C-shaped slot etched on the square radiating part and the antenna is energized using microstrip feed line. RT Duroid (ε r= 2.2), Taconic (ε r= 3.2) and FR4 (ε r= 4.4) substrates are used for simulation analysis. The flow of current is modified by the C-shaped slot making the antenna to resonate at 3/4 and 6 bands for RT Duroid/Taconic and FR4 substrates respectively suitable for 5G sub GHz applications. The antenna has a compact dimension of 32 × 32 × 1.6 mm 3 and exhibits a return loss, S11 of less than -10dB for all the resonating frequencies for all three substrates. The analysis has been done by considering the S11 (Return loss <-10 dB), Directivity, Antenna Gain, VSWR and surface current distribution. Table II provides the comparison of parameters for different substrate material.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 4; 715--719
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fading Channel Prediction for 5G and 6G Mobile Communication Systems
Autorzy:
Soszka, Maciej
Powiązania:
https://bibliotekanauki.pl/articles/2055227.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
5G
6G
channel prediction
channel state information
sub-6 GHz
millimetre-wave
neural network
artificial intelligence
narrowband
wide band
ultra wide band
Opis:
Nowadays, there is a trend to employ adaptive solutions in mobile communication. The adaptive transmission systems seem to answer the need for highly reliable communication that serves high data rates. For efficient adaptive transmission, the future Channel State Information (CSI) has to be known. The various prediction methods can be applied to estimate the future CSI. However, each method has its bottlenecks. The task is even more challenging while considering the future 5G/6G communication where the employment of sub-6 GHz and millimetre waves (mmWaves) in narrow-band, wide-band and ultra-wide-band transmission is considered. Thus, author describes the differences between sub-6 GHz/mmWave and narrow-band/wide-band/ultra-wide-band channel prediction, provide a comprehensive overview of available prediction methods, discuss its performance and analyse the opportunity to use them in sub-6 GHz and mmWave systems. We select Long Short-Term Memory Recurrent Neural Network (RNN) as the most promising technique for future CSI prediction and propose optimising two of its parameters - the number of input features, which was not yet considered as an opportunity to improve the performance of CSI prediction, and the number of hidden layers.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 1; 153--160
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Study on Packet Scheduling Algorithms for Healthcare Contents over Fifth Generation (5G) Mobile Cellular Network
Autorzy:
Ramli, Huda Adibah Mohd
Powiązania:
https://bibliotekanauki.pl/articles/1844466.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
packet scheduling
5G
flexible frame structure
transmission reliability
scalable TTI
Opis:
This paper models the downlink Fifth Generation (5G) network that supports a flexible frame structure and a shorter Round-Trip Time (RTT) for Hybrid Automatic Repeat Request (HARQ). Moreover, the design of the renowned Time Division Multiple Access (TDMA) packet scheduling algorithms is revised to allow these algorithms to support packet scheduling in the downlink 5G. Simulation results demonstrate that the Proportional Fair provides a comparable performance to the delay–aware Maximum-Largest Weighted Delay First for simultaneously providing the desired transmission reliability of the Guaranteed Bit Rate (GBR) and Non-Guaranteed Bit Rate (Non - GBR) healthcare contents whilst maximizing the downlink 5G performance.
Źródło:
International Journal of Electronics and Telecommunications; 2020, 66, 4; 729-735
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of Latency-Aware Network Slicing in 5G Packet xHaul Networks
Autorzy:
Klinkowski, Mirosław
Powiązania:
https://bibliotekanauki.pl/articles/27311921.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
5G
radio access networks
packet-switched xHaul
latency-sensitive network
network slicing
traffic prioritization
network optimization
Opis:
Packet-switched xHaul networks are a scalable solution enabling convergent transport of diverse types of radio data flows, such as fronthaul / midhaul / backhaul (FH / MH / BH) flows, between remote sites and a central site (hub) in 5G radio access networks (RANs). Such networks can be realized using the cost-efficient Ethernet technology, which enhanced with time-sensitive networking (TSN) features allows for prioritized transmission of latency-sensitive fronthaul flows. Provisioning of multiple types of 5G services of different service requirements in a shared network, commonly referred to as network slicing, requires adequate handling of transported data flows in order to satisfy particular service / slice requirements. In this work, we investigate two traffic prioritization policies, namely, flowaware (FA) and latency-aware (LA), in a packet-switched xHaul network supporting slices of different latency requirements. We evaluate the effectiveness of the policies in a networkplanning case study, where virtualized radio processing resources allocated at the processing pool (PP) facilities, for two slices related to enhanced mobile broadband (eMBB) and ultra-reliable low latency communications (URLLC) services, are subject to optimization. Using numerical experiments, we analyze PP cost savings from applying the LA policy (vs. FA) in various network scenarios. The savings in active PPs reach up to 40% − 60% in ring scenarios and 30% in a mesh network, whereas the gains in overall PP cost are up to 20% for the cost values assumed in the analysis.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 2; 335--340
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on Metamaterial-based Bio-inspired Microstrip Antenna Array for 5G Enabled Mobile Health Technology
Autorzy:
Colaco, John
Cotta, Jillian
Powiązania:
https://bibliotekanauki.pl/articles/2055230.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
microstrip
antenna
bio-inspired
array
split-ring
resonators
metamaterial
5G
Opis:
5G is a fifth-generation wireless technology that enables extremely fast data transfers and massive connection capacity. Existing Mobile health technology requires more reliable connection power and data transfer rates. The purpose of this research is to design, analyse, and compare the performance of a bio-inspired lotus-shaped microstrip patch antenna array with two to three radiating elements. The proposed antenna utilizes proximity coupled indirect microstrip transmission line feeding technique operating in the 24 GHz-30 GHz frequency band. The results indicate that performance continues to improve as the number of radiating elements increases. Moreover, each radiating element is loaded with complementary and non-complementary split-ring resonators (SRRs). The performance of the proposed microstrip antenna array is then analysed and compared with and without split-ring resonators. The findings validate that the proposed bio-inspired metamaterial-based microstrip patch array antenna is more reliable and performs better than an antenna without SRRs.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 2; 201--207
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zipf Distribution Power AllocationAapproach for NOMA Systems
Autorzy:
Himeur, Hanane
Meriah, Sidi Mohammed
Derraz, Fouad
Powiązania:
https://bibliotekanauki.pl/articles/27311910.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
NOMA
wireless networks
power domain
Zipf distribution law
5G networks
Opis:
Non-orthogonal multiple access (NOMA) has received tremendous attention for the development of 5G and beyond wireless networks. Power-domain NOMA works on the concept of assigning varying power levels to users within the same frequency and time block. In this paper we propose a novel power allocation approach that uses the Zipf distribution law that satisfies the basic condition of a NOMA system. The Zipf PA is characterized by the simplicity and ease of implementation that allows to extend the capacity of the system to support a large number of users. The numerical results show that the system achieves high throughput and energy efficiency without any parameter optimization constraints as well as improved capacity by increasing the number of users compared to the NOMA system with existing power allocation techniques.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 3; 559--564
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design and Simulation of 2× 2Micro Strip Circular Patch Antenna Array at 28 GHz for 5G Mobile Station Application
Autorzy:
Hasan, Salim Abdullah
Ahmed, Abdulsattar Mohamed
Abdulqader, Mohanad Nawfal
Dawood, Younis Shareef
Powiązania:
https://bibliotekanauki.pl/articles/2200728.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
patch
5G
return loss
dielectric
array
divider
substrate
directivity
bandwidth
Opis:
This paper proposes the design and simulation of 2×2 circular patch antenna array working at 28 GHz by using four inset feed micro strip circular patch antennas to achieve beam forming with directivity around 13dB which is required to overcome part of high path loss challenge for high data rate mm-5G mobile station application. Four element 2x2 array consists of two 1x2 circular patch antenna arrays based on power divider and quarter wavelength transition lines as a matching circuit. The designed antenna array is simulated on RT/duroid 5880 dielectric substrate with properties of 0.5mm thickness, dielectric constant ε r =2.2, and tangent loss of 0.0009 by using Computer System Technology (CST) software. The performances in terms of return loss, 3D–radiation pattern is evaluated at 28 GHz frequency band. The design also includes the possibility of inserting four identical 2x2 antenna arrays at four edges of mobile station substrate to achieve broad space coverage by steering the beams of the mobile station arrays.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 4; 721--729
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł

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