scholarly journals Wireless communications beyond 5G: Uncertainties of terahertz wave attenuation due to rain

2018 ◽  
Vol 58 (2) ◽  
Author(s):  
Milda Tamošiūnaitė ◽  
Vincas Tamošiūnas ◽  
Gintaras Valušis
Keyword(s):  
Wireless Networks ◽  
Data Transmission ◽  
Wave Attenuation ◽  
Heavy Rain ◽  
Terahertz Wave ◽  
Industrial Test ◽  
Future Application ◽  
The Real ◽  
Simulation Results ◽  
Drop Size Distributions

Statistical peculiarities of terahertz (THz) wave attenuation in heavy rain conditions are evaluated. The expected extreme densification of the infrastructure and the application of highly directional beams of 5th generation (5G) and beyond 5G (B5G) wireless networks were taken into account. Calculations were performed emulating both drop size distributions of the real rain and the laboratory-controlled rain described in literature. Simulation results revealed that absorbance fluctuations of more than one percent would occur if THz waves and raindrops interact within the 100 m3volume. For much smaller volumes, short distances and narrow beams used for experiments with the laboratory-controlled rain, absorbance uncertainties could exceed the average absorbance value. A comparison of the simulation results at fixed average absorbance revealed that slightly lower uncertainties were expected in the case of a single raindrop size when compared to the Weibull distribution approximating the real rain. Nevertheless, in both cases the predicted deviations were substantially smaller than observed in the previously published experimental results. This fact predicts a new future application possibility for such laboratory-based experiments – they can be employed to predict the performance of wireless THz data transmission links when the resilience margin is required. Since much of the existing industrial test equipment is not designed to carry out calibrated over-the-air measurements of 5G/B5G wireless networks, such experiments can be employed to primarily predict the performance of data transmission links.

scholarly journals Hybrid Congestion Sharing and Route Repairing Protocol for Bluetooth Networks

2021 ◽  
Vol 20 ◽  
pp. 49-55
Author(s):  
Sabeen Tahir ◽  
Ghadah Abdullah Aldabbagh ◽  
Sheikh Tahir Bakhsh ◽  
Abass Md Said
Keyword(s):  
Wireless Networks ◽  
Data Transmission ◽  
Congestion Avoidance ◽  
Wireless Technology ◽  
Reconstruction Process ◽  
Technical Problems ◽  
Route Maintenance ◽  
Technology Standard ◽  
Congestion Problems ◽  
Simulation Results

Bluetooth is a widespread wireless technology standard for limited wireless networks that permits Bluetooth devices to create a one-hop (piconet) or multi-hop (scatternet) network. During data transmission, a large number of links passing through a single master or bridge device may create congestion problems in a Bluetooth network. Therefore, routing in a multi-hop dynamic Bluetooth network, where a number of routing masters and routing bridges exist, sometimes create technical problems in a scatternet. Mobility and failure of routing devices disconnects the routing links and link reconstruction process consumes more resources that eventually decrease the performance. In this paper, Hybrid Congestion Sharing and Route Repairing protocol for Bluetooth networks” (HCSRR) is proposed. The objective of this paper is to provide an efficient technique for scatternet congestion avoidance and route maintenance. The proposed protocol is implemented and compared with most relevant protocols. From simulation results, it is observed that the HCSRR outperforms the existing protocols.

Factual Power Loss Diminution by Enhanced Frog Leaping Algorithm

2020 ◽  
Vol 3 (2) ◽  
pp. 114-118
Author(s):  
Kanagasabai Lenin
Keyword(s):  
Local Search ◽  
Power Loss ◽  
Reactive Power ◽  
Test System ◽  
Premature Convergence ◽  
Speed Of Convergence ◽  
Real Power ◽  
The Real ◽  
Simulation Results ◽  
Power Problem

This paper proposes Enhanced Frog Leaping Algorithm (EFLA) to solve the optimal reactive power problem. Frog leaping algorithm (FLA) replicates the procedure of frogs passing though the wetland and foraging deeds. Set of virtual frogs alienated into numerous groups known as “memeplexes”. Frog’s position’s turn out to be closer in every memeplex after few optimization runs and certainly, this crisis direct to premature convergence. In the proposed Enhanced Frog Leaping Algorithm (EFLA) the most excellent frog information is used to augment the local search in each memeplex and initiate to the exploration bound acceleration. To advance the speed of convergence two acceleration factors are introduced in the exploration plan formulation. Proposed Enhanced Frog Leaping Algorithm (EFLA) has been tested in standard IEEE 14,300 bus test system and simulation results show the projected algorithm reduced the real power loss considerably.

A Dicode Signaling Scheme for Capacitively Coupled Interface

2011 ◽  
Vol 497 ◽  
pp. 296-305
Author(s):  
Yasushi Yuminaka ◽  
Kyohei Kawano
Keyword(s):  
Partial Response ◽  
Data Transmission ◽  
High Speed ◽  
Circuit Simulation ◽  
Frequency Bandwidth ◽  
Capacitively Coupled ◽  
Limited Frequency ◽  
Simulation Results ◽  
Response Coding ◽  
The Impact

In this paper, we present a bandwidth-efficient partial-response signaling scheme for capacitivelycoupled chip-to-chip data transmission to increase data rate. Partial-response coding is knownas a technique that allows high-speed transmission while using a limited frequency bandwidth, by allowingcontrolled intersymbol interference (ISI). Analysis and circuit simulation results are presentedto show the impact of duobinary (1+D) and dicode (1-D) partial-response signaling for capacitivelycoupled interface.

An improved method to estimate Q based on the logarithmic spectrum of moving peak points

2019 ◽  
Vol 7 (2) ◽  
pp. T255-T263 ◽  
Author(s):  
Yanli Liu ◽  
Zhenchun Li ◽  
Guoquan Yang ◽  
Qiang Liu
Keyword(s):  
Seismic Waves ◽  
Wave Attenuation ◽  
Real Data ◽  
Peak Frequency ◽  
Seismic Reflection Data ◽  
The Real ◽  
Time Frequency ◽  
Reflection Data ◽  
Text Filtering ◽  
The Impact

The quality factor ([Formula: see text]) is an important parameter for measuring the attenuation of seismic waves. Reliable [Formula: see text] estimation and stable inverse [Formula: see text] filtering are expected to improve the resolution of seismic data and deep-layer energy. Many methods of estimating [Formula: see text] are based on an individual wavelet. However, it is difficult to extract the individual wavelet precisely from seismic reflection data. To avoid this problem, we have developed a method of directly estimating [Formula: see text] from reflection data. The core of the methodology is selecting the peak-frequency points to linear fit their logarithmic spectrum and time-frequency product. Then, we calculated [Formula: see text] according to the relationship between [Formula: see text] and the optimized slope. First, to get the peak frequency points at different times, we use the generalized S transform to produce the 2D high-precision time-frequency spectrum. According to the seismic wave attenuation mechanism, the logarithmic spectrum attenuates linearly with the product of frequency and time. Thus, the second step of the method is transforming a 2D spectrum into 1D by variable substitution. In the process of transformation, we only selected the peak frequency points to participate in the fitting process, which can reduce the impact of the interference on the spectrum. Third, we obtain the optimized slope by least-squares fitting. To demonstrate the reliability of our method, we applied it to a constant [Formula: see text] model and the real data of a work area. For the real data, we calculated the [Formula: see text] curve of the seismic trace near a well and we get the high-resolution section by using stable inverse [Formula: see text] filtering. The model and real data indicate that our method is effective and reliable for estimating the [Formula: see text] value.

A Small World Routing Protocol in Wireless Sensor Networks

2011 ◽  
Vol 474-476 ◽  
pp. 828-833
Author(s):  
Wen Jun Xu ◽  
Li Juan Sun ◽  
Jian Guo ◽  
Ru Chuan Wang
Keyword(s):  
Wireless Sensor Networks ◽  
Sensor Networks ◽  
Routing Protocol ◽  
Data Transmission ◽  
Small World ◽  
Wireless Sensor ◽  
Small World Network ◽  
Average Delay ◽  
Network Diameter ◽  
Simulation Results

In order to reduce the average path length of the wireless sensor networks (WSNs) and save the energy, in this paper, the concept of the small world is introduced into the routing designs of WSNs. So a new small world routing protocol (SWRP) is proposed. By adding a few short cut links, which are confined to a fraction of the network diameter, we construct a small world network. Then the protocol finds paths through recurrent propagations of weak and strong links. The simulation results indicate that SWRP reduces the energy consumption effectively and the average delay of the data transmission, which leads to prolong the lifetime of both the nodes and the network.

Dynamic Effect Simulation of Snow Falling Based on Particle System

2014 ◽  
Vol 651-653 ◽  
pp. 1840-1843
Author(s):  
Ying Ying Yin
Keyword(s):  
Particle System ◽  
Dynamic Effect ◽  
It Use ◽  
The Real ◽  
Real Effects ◽  
Simulation Results ◽  
Natural Characteristics ◽  
Calculated Model

To simulate snow falling scene dynamically, a method based on particle system is presented to simulate snow falling effects, it use calculated model to simulate the real effects of snow falling in the basis of snow natural characteristics. The simulation results have proven that the proposed method is more effective for simulating snow falling with realistic effects.

MINIMUM CONNECTED r-HOP k-DOMINATING SET IN WIRELESS NETWORKS

2009 ◽  
Vol 01 (01) ◽  
pp. 45-57 ◽  
Author(s):  
DEYING LI ◽  
LIN LIU ◽  
HUIQIANG YANG
Keyword(s):  
Wireless Networks ◽  
Undirected Graph ◽  
Dominating Set ◽  
Approximation Ratio ◽  
Dominating Set Problem ◽  
Simulation Results

In this paper, we study the connected r-hop k-dominating set problem in wireless networks. We propose two algorithms for the problem. We prove that algorithm I for UDG has (2r + 1)3 approximate ratio for k ≤ (2r + 1)2 and (2r + 1)((2r + 1)2 + 1)-approximate ratio for k > (2r + 1)2. And algorithm II for any undirected graph has (2r + 1) ln (Δr) approximation ratio, where Δr is the largest cardinality among all r-hop neighborhoods in the network. The simulation results show that our algorithms are efficient.

Traffic Congestion Reduction and Accident Circumvention System via Incorporation of CAV and VANET

2021 ◽  
Vol 12 (1) ◽  
pp. 53-72
Author(s):  
Mohsin Khan ◽  
Bhavna Arora
Keyword(s):  
Real Time ◽  
Data Transmission ◽  
Traffic Congestion ◽  
Ad Hoc Network ◽  
Discrete System ◽  
Ad Hoc ◽  
New Age ◽  
The Real ◽  
Automated Vehicle ◽  
The Core

Connected automated vehicle (CAV) technology is the core for the new age vehicles in research phase to communicate with one another and assimilation of vehicular ad-hoc network (VANET) for the transference of data between vehicles at a quantified place and time. This manuscript is an enactment of the algorithms associated to the maintenance of secure distance amongst vehicles, lane shifting, and overtaking, which will diminish the occurrence of collisions and congestions especially phantom jams. Those implementations are centered over CAV and VANET technology for the interconnection of the vehicles and the data transmission. The data is associated to the aspects of a vehicle such as speed, position, acceleration, and acknowledgements, which acts as the fundamentals for the computation of variables. In accordance with the environment of a particular vehicle (i.e., its surrounding vehicles), real-time decisions are taken based on the real-time computation of the variables in a discrete system.

Bidirectional Hybrid Optical Communication System Based on Wavelength Division Multiplexing for Outdoor Applications

2021 ◽  
Author(s):  
Sinan M. Abdulsatar ◽  
Mohammed A. Saleh ◽  
Abadulla Abass ◽  
M. H. Ali ◽  
Mohammed Ali Yaseen
Keyword(s):  
Wavelength Division Multiplexing ◽  
Optical Communication ◽  
Data Transmission ◽  
Communication System ◽  
Optical Switch ◽  
Heavy Rain ◽  
Free Space Optical ◽  
Wavelength Division ◽  
Backup System ◽  
All Optical

Abstract The simulation and investigation of a 32×10 Gb/s WDM all–optical bidirectional hybrid communication system for outdoor applications is presented in this article via multidisciplinary softwares. In order to track the system condition, a strain sensor based on fiber Bragg grating (FBG) is integrated in–line with the fiber optic link (FO–link). Then, a free space optical link (FSO–link) with 4–channel is simulated to act backup or rescue to the FO–link in the event of disaster or bombing. The FO–link is working well until the strain reach to 180 µε, after that the FO–link has degraded. Therefore, an optical switch is incorporated in between these systems (FO–link & FSO–link) to turn–on the FSO–link which act as a backup system to FO–link and maintains the continuity of the data transmission. According to the hybrid link results, there is an efficient enhancement in the Q–factor as compared with the FO–link even when there is heavy rain.

scholarly journals Adaptive algorithm based on antenna arrays for radio communication systems

2017 ◽  
Vol 14 (3) ◽  
pp. 301-312 ◽  
Author(s):  
Valentin Fedosov ◽  
Andrey Legin ◽  
Anna Lomakina
Keyword(s):  
Wireless Networks ◽  
Antenna Arrays ◽  
Data Transmission ◽  
Communication Systems ◽  
Electromagnetic Compatibility ◽  
Signal Propagation ◽  
Time Signal ◽  
Adaptive Antenna ◽  
Spatial Coding ◽  
Multiple Input

Trends in the modern world increasingly lead to the growing popularity of wireless technologies. This is possible due to the rapid development of mobile communications, the Internet gaining high popularity, using wireless networks at enterprises, offices, buildings, etc. It requires advanced network technologies with high throughput capacity to meet the needs of users. To date, a popular destination is the development of spatial signal processing techniques allowing to increase spatial bandwidth of communication channels. The most popular method is spatial coding MIMO to increase data transmission speed which is carried out due to several spatial streams emitted by several antennas. Another advantage of this technology is the bandwidth increase to be achieved without expanding the specified frequency range. Spatial coding methods are even more attractive due to a limited frequency resource. Currently, there is an increasing use of wireless communications (for example, WiFi and WiMAX) in information transmission networks. One of the main problems of evolving wireless systems is the need to increase bandwidth and improve the quality of service (reducing the error probability). Bandwidth can be increased by expanding the bandwidth or increasing the radiated power. Nevertheless, the application of these methods has some drawbacks, due to the requirements of biological protection and electromagnetic compatibility, the increase of power and the expansion of the frequency band is limited. This problem is especially relevant in mobile (cellular) communication systems and wireless networks operating in difficult signal propagation conditions. One of the most effective ways to solve this problem is to use adaptive antenna arrays with weakly correlated antenna elements. Communication systems using such antennas are called MIMO systems (Multiple Input Multiple Output multiple input - multiple outputs). At the moment, existing MIMO-idea implementations do not always noticeably accelerate traffic at short distances from the access point, but, they are very effective at long distances. The MIMO principle allows reducing the number of errors in radio data interchange (BER) without reducing the transmission rate under conditions of multiple signal re-reflections. The work aims at developing an adaptive space-time signal algorithm for a wireless data transmission system designed to improve the efficiency of this system, as well as to study the efficiency of the algorithm to minimizing the error bit probability and maximizing the channel capacity.

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