scholarly journals A Low-Complexity Reconfigurable Multi-Antenna Technique for Non-Terrestrial Networks

2021 ◽  
Vol 2 ◽  
Author(s):  
Konstantinos Maliatsos ◽  
Petros S. Bithas ◽  
Athanasios G. Kanatas
Keyword(s):  
Communication Networks ◽  
Antenna Arrays ◽  
Communication System ◽  
Communication Systems ◽  
Channel Model ◽  
Markov Chain Model ◽  
Main Idea ◽  
Low Complexity ◽  
Chain Model ◽  
Ground Station

Multi-Antenna communication techniques are an efficient and relatively simple approach for the performance improvement of wireless communication systems. However, the direct application of multi-antenna techniques to an aerial communication system is not always feasible due to the constraints induced by the aerial platforms. Reconfigurable intelligent antenna technologies could provide an efficient solution to these problems and thus they are considered as ideal candidates for adaption in the aerial communication platforms that will be used in the 5G and beyond communication networks. In this paper, a joint Tx-Rx beamforming with beam selection and combining technique is proposed for improving the performance of an aerial communication system supported by electronically steerable antenna arrays. The main idea of the proposed scheme is to select, using an SNR maximization criterion, a pair of beam patterns between each RF chain of the ground station and the aerial platform, and combine the received SNRs under the maximal ratio principle. Initially, an analytical stochastic framework has been developed that is based on a Markov chain model, which is used to investigate the statistics of the received SNR. Then, an implementation of the novel beamforming and pattern adaptation scheme is presented, with the use of Electronically Steerable Parasitic Array Radiators (ESPAR), properly designed for Ground Station to UAV links. In addition, a realistic simulator is also developed with proper channel model selection, by the aid of which, the performance of the proposed scheme has been evaluated in conjunction with the extracted analytical results.

scholarly journals Principles of adaptive element spacing in linear array antennas

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tanzeela Mitha ◽  
Maria Pour
Keyword(s):  
Antenna Arrays ◽  
Communication Systems ◽  
Linear Array ◽  
Main Idea ◽  
Phase Center ◽  
Array Configuration ◽  
Array Antennas ◽  
Center Location ◽  
Novel Approach ◽  
Array Performance

AbstractA novel approach to linear array antennas with adaptive inter-element spacing is presented for the first time. The main idea is based upon electronically displacing the phase center location of the antenna elements, which determine their relative coordinates in the array configuration. This is realized by employing dual-mode microstrip patch antennas as a constitutive element, whose phase center location can be displaced from its physical center by simultaneously exciting two modes. The direction and the amount of displacement is controlled by the amplitude and phase of the modes at the element level. This in turn facilitates reconfiguring the inter-element spacing at the array level. For instance, a uniformly-spaced array could be electronically transformed into a non-uniform one without any mechanical means. The proposed idea is demonstrated in two- and three-element linear antenna arrays. The technique has the potential to control the radiation characteristics such as sidelobe levels, position of the nulls, and the beamwidths in small arrays, which are useful for adaptively controlling the array performance in emerging wireless communication systems and radars.

Design and Analysis of a Reliable Communication System in Nuclear Safety Instrument & Control System

2021 ◽  
Author(s):  
Le Li ◽  
Zhihui Zhang ◽  
Chao Gao ◽  
Fei Zhou ◽  
Guangqiang Ma
Keyword(s):  
Communication Networks ◽  
Communication System ◽  
Communication Systems ◽  
Nuclear Power ◽  
Data Exchange ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Nuclear Safety ◽  
Safety Communication ◽  
Digital Control Systems

Abstract With the development of digital instrument and control technology for nuclear power plants in recent decades, communication networks have become an important part of safety digital control systems, which takes charge in data exchange between the various sub-systems, and extremely impact on the reliability and safety of the entire I&C system. Traditional communication systems where some special features, such as reliability, safety, real-time, certainty, and independence are not strictly required are various illustrated. However, how to implement a communication system in a safety I&C system is rarely stated in current research. In this research, a reliable safety communication system applied in nuclear power plants is designed and analyzed. The five key characteristics of nuclear safety communication networks are explained, followed by explanation of how to achieve these characteristics. The analysis and verification of the designed system are also stated in this paper, which contributes to proving that the designed nuclear safety communication system could applied in the nuclear power plants.

scholarly journals A Novel Detection Scheme for EBPSK System

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Xianqing Chen ◽  
Lenan Wu
Keyword(s):  
Communication System ◽  
Communication Systems ◽  
Low Complexity ◽  
Detection Technique ◽  
Joint Detection ◽  
Phase Shift Keying ◽  
Detection Scheme ◽  
New Approach ◽  
Shift Keying ◽  
Binary Phase Shift Keying

We introduce the extended binary phase shift keying (EBPSK) communication system which is different from traditional communication systems by using a special impacting filter (SIF) for demodulation. The joint detection technique is applied at the demodulator side in order to improve the performance of the system under intersymbol interference (ISI). The main advantage of the joint detection technique, when compared to conventional threshold approaches, lies in its ability to use the amplitude and the correlation between neighboring bits, thus significantly improving performance, with low complexity. Moreover, we concentrate not only on increasing the bit rate of the system, but also on designing a bandwidth efficient communication system. Simulation results show that this new approach significantly outperforms the conventional method of using threshold decision by from 3.5 to 5 dB. The new system also occupies a narrower bandwidth. So joint detection is an effective method for EBPSK demodulation under ISI.

An improved peak side lobe reduction method for linear array antenna for military applications

2021 ◽  
Vol 14 (2) ◽  
pp. 186-198
Author(s):  
Ravi Tej D ◽  
Sri Kavya Ch K ◽  
Sarat K. Kotamraju
Keyword(s):  
Energy Efficiency ◽  
Antenna Array ◽  
Antenna Arrays ◽  
Spectral Efficiency ◽  
Communication System ◽  
Communication Systems ◽  
Side Lobe ◽  
Side Lobe Level ◽  
Fill Rate ◽  
Content Type

PurposeThe purpose of this paper is to improve energy efficiency and further reduction of side lobe level the algorithm proposed is firework algorithm. In this paper, roused by the eminent swarm conduct of firecrackers, a novel multitude insight calculation called fireworks algorithm (FA) is proposed for work enhancement. The FA is introduced and actualized by mimicking the blast procedure of firecrackers. In the FA, two blast (search) forms are utilized and systems for keeping decent variety of sparkles are likewise all around planned. To approve the presentation of the proposed FA, correlation tests were led on nine benchmark test capacities among the FA, the standard PSO (SPSO) and the clonal PSO (CPSO).Design/methodology/approachThe antenna arrays are used to improve the capacity and spectral efficiency of wireless communication system. The latest communication systems use the antenna array technology to improve the spectral efficiency, fill rate and the energy efficiency of the communication system can be enhanced. One of the most important properties of antenna array is beam pattern. A directional main lobe with low side lobe level (SLL) of the beam pattern will reduce the interference and enhance the quality of communication. The classical methods for reducing the side lobe level are differential evolution algorithm and PSO algorithm. In this paper, roused by the eminent swarm conduct of firecrackers, a novel multitude insight calculation called fireworks algorithm (FA) is proposed for work enhancement. The FA is introduced and actualized by mimicking the blast procedure of firecrackers. In the FA, two blast (search) forms are utilized and systems for keeping decent variety of sparkles are likewise all around planned. To approve the presentation of the proposed FA, correlation tests were led on nine benchmark test capacities among the FA, the standard PSO (SPSO) and the clonal PSO (CPSO). It is demonstrated that the FA plainly beats the SPSO and the CPSO in both enhancement exactness and combination speed. The results convey that the side lobe level is reduced to −34.78dB and fill rate is increased to 78.53.FindingsSamples including 16-element LAAs are conducted to verify the optimization performances of the SLL reductions. Simulation results show that the SLLs can be effectively reduced by FA. Moreover, compared with other benchmark algorithms, fireworks has a better performance in terms of the accuracy, the convergence rate and the stability.Research limitations/implicationsWith the use of algorithms radiation is prone to noise one way or other. Even with any optimizations we cannot expect radiation to be ideal. Power dissipation or electro magnetic interference is bound to happen, but the use of optimization algorithms tries to reduce them to the extent that is possible.Practical implications16-element linear antenna array is available with latest versions of Matlab.Social implicationsThe latest technologies and emerging developments in the field of communication and with exponential growth in users the capacity of communication system has bottlenecks. The antenna arrays are used to improve the capacity and spectral efficiency of wireless communication system. The latest communication systems use the antenna array technology which is to improve the spectral efficiency, fill rate and the energy efficiency of the communication system can be enhanced.Originality/valueBy using FA, the fill rate is increased to 78.53 and the side lobe level is reduced to 35dB, when compared with the bench mark algorithms.

scholarly journals Massive MIMO Channel Models: A Survey

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Kan Zheng ◽  
Suling Ou ◽  
Xuefeng Yin
Keyword(s):  
Wireless Communication ◽  
Antenna Array ◽  
Communication Networks ◽  
Massive Mimo ◽  
Communication Systems ◽  
Channel Model ◽  
Spectrum Efficiency ◽  
Mimo Channel ◽  
Wireless Communication Networks ◽  
Channel Models

The exponential traffic growth of wireless communication networks gives rise to both the insufficient network capacity and excessive carbon emissions. Massive multiple-input multiple-output (MIMO) can improve the spectrum efficiency (SE) together with the energy efficiency (EE) and has been regarded as a promising technique for the next generation wireless communication networks. Channel model reflects the propagation characteristics of signals in radio environments and is very essential for evaluating the performances of wireless communication systems. The purpose of this paper is to investigate the state of the art in channel models of massive MIMO. First, the antenna array configurations are presented and classified, which directly affect the channel models and system performance. Then, measurement results are given in order to reflect the main properties of massive MIMO channels. Based on these properties, the channel models of massive MIMO are studied with different antenna array configurations, which can be used for both theoretical analysis and practical evaluation.

Simplest Flow Queuing Models for LEO Satellite System

2022 ◽  
pp. 61-70
Author(s):  
S.B. Pichugin
Keyword(s):  
Communication System ◽  
Communication Systems ◽  
Satellite System ◽  
Low Earth Orbit ◽  
Analytical Models ◽  
Mathematical Apparatus ◽  
Satellite Systems ◽  
Ground Station ◽  
Queuing Models ◽  
Leo Satellite

The relevance of the work is associated with the active deployment of low-orbit communication systems and the expansion of research in the field of corresponding satellite systems. A promising low-orbit communication system based on relay satellites with the function (RSRFs) of routing message packets is considered. The low earth orbit communications systems use the BGP protocol and the AAA functionality at the ground station. For assessing the characteristics of RSRF inter-satellite paths, a scenario was created for the message packets arrival from a group of inter-satellite paths to one subscriber path. The corresponding analytical models have been developed using the mathematical apparatus of queuing systems with the simplest flows of requests and exponential distribution of the service time. The RSRF characteristics of a promising low-orbit communication system are predicted. It is proposed to make the mathematical apparatus of analytical models more complicated to take into account the dynamics of displacements and failures of the RSRF in a low-orbit communication system.

scholarly journals Modeling of Random Delays in Networked Control Systems

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Yuan Ge ◽  
Qigong Chen ◽  
Ming Jiang ◽  
Yiqing Huang
Keyword(s):  
Control Systems ◽  
Communication Networks ◽  
Networked Control Systems ◽  
Markov Chain Model ◽  
Networked Control ◽  
Chain Model ◽  
Delay Model ◽  
Packet Losses ◽  
Control Loops ◽  
Random Delays

In networked control systems (NCSs), the presence of communication networks in control loops causes many imperfections such as random delays, packet losses, multipacket transmission, and packet disordering. In fact, random delays are usually the most important problems and challenges in NCSs because, to some extent, other problems are often caused by random delays. In order to compensate for random delays which may lead to performance degradation and instability of NCSs, it is necessary to establish the mathematical model of random delays before compensation. In this paper, four major delay models are surveyed including constant delay model, mutually independent stochastic delay model, Markov chain model, and hidden Markov model. In each delay model, some promising compensation methods of delays are also addressed.

Stability and performance analysis of wireless powered communication networks

2021 ◽  
pp. 1748006X2110167
Author(s):  
Mingfu Li ◽  
Ching-Chieh Fang ◽  
Huei-Wen Ferng
Keyword(s):  
Communication Networks ◽  
Stability Condition ◽  
Transmission Rate ◽  
Markov Chain Model ◽  
Packet Delay ◽  
Finite Energy ◽  
Chain Model ◽  
Wireless Charging ◽  
Charging Rate ◽  
Wireless Device

In RF-based wireless powered communication networks (WPCNs), the wireless charging rate at a device is usually low or unstable because of health concerns or time-varying characteristics of wireless channels. Under a low charging rate, the data backlog at a wireless device may be continuously increasing, leading to system performance degradation and data loss. To keep a wireless powered device stable and preserve a finite data backlog, the upper limit of data arrival/acquisition rate at a wireless powered device must be solved under the given data transmission rate and wireless charging rate. Hence, in this paper a novel two-dimensional continuous-time Markov chain model was proposed for analyzing the stability condition of a wireless powered device with a finite energy storage buffer. The average number of data packets, average packet delay, and energy shortage probability at a wireless powered device were analyzed as well. Additionally, simulations were conducted to validate the analytic results and demonstrate that the obtained stability condition is necessary and sufficient for the wireless device.

scholarly journals Millimeter wave patch antenna array for 5G wireless communication systems

2019 ◽  
Vol 27 (2) ◽  
pp. 105-110
Author(s):  
A. B. Gnilenko ◽  
S. V. Plaksin
Keyword(s):  
Wireless Communication ◽  
Antenna Array ◽  
Millimeter Wave ◽  
Antenna Arrays ◽  
Communication System ◽  
Patch Antenna ◽  
Communication Systems ◽  
High Capacity ◽  
Angular Width ◽  
Wireless Communication System

Millimeter waves are now considered as an important part of 5G spectrum. Higher frequencies provide larger bandwidth giving the ability to support very high data rate, ultra high capacity and very low latency. The utilization of millimeter wave frequency bands for 5G mobile applications requires effective solutions in the design of antennas and antenna arrays which are the key parts of modern communication systems. In this paper a 4x4 microstrip patch antenna array sub-module is presented to be a part of 5G wireless communication system. The antenna array is designed and optimized to operate at a frequency of 85 GHz which corresponds to the middle of the second atmospheric transparency window. The antenna array is simulated using the time domain solver of the CST Microwave Studio software package. Simulation results are demonstrated and discussed for an optimized array. The designed patch antenna array provides good directivity characteristics with a main lobe magnitude of 16 dBi, angular width of 28 degree and can be applied as a part of a wireless communication system operating at a high frequency band of 5G frequency range.

Sign in / Sign up

Export Citation Format

Share Document