scholarly journals Path-loss modelling for WSN deployment in indoor and outdoor environments for medical applications

2018 ◽  
Vol 7 (3) ◽  
pp. 1666 ◽  
Author(s):  
Ahmed Bashar Fakhri ◽  
Sadik Kamel Gharghan ◽  
Saleem Latteef Mohammed
Keyword(s):  
Standard Deviation ◽  
Multipath Propagation ◽  
Path Loss ◽  
Medical Application ◽  
Indoor Environments ◽  
Data Packets ◽  
And Performance ◽  
Log Normal ◽  
Loss Modelling ◽  
Indoor And Outdoor Environments

Wireless sensor networks (WSNs) and their applications have received significantly interested in the last few years. In WSN, knowing an accurate path-loss model as well as packet delivery should be taken into account for the successful distribution of several nodes in the net-work. This paper presents a path-loss modeling and performance evaluation of the ZigBee wireless standard. Received signal strength indi-cator (RSSI) measurements were achieved in outdoor and indoor environments to derive the path-loss based on Log-Normal Shadowing Model (LNSM). The path-loss parameters such as standard deviation and path loss exponents were estimated over point-to-point ZigBee WSN. In addition, the variances of received RSSI values and standard deviation for these values have been investigated. Furthermore, the data packets received is measured practically. Results revealed that the LNSM can be estimated to reflect the channel losses in both outdoor and indoor environments for medical application. The data delivery was achieved successfully of 100% in outdoor which better than indoor due to multipath propagation and shadowing. Moreover, the data packets delivery of the current work outperformed previous work.  

scholarly journals Path Loss Characterization in an Indoor Laboratory Environment at 3.7 GHz in in Line-Of-Sight Condition

2020 ◽  
Vol 29 (54) ◽  
pp. e12015
Author(s):  
Sandy Enrique Avella-Cely ◽  
Juan Carlos Muñoz-Pérez ◽  
Herman Antonio Fernández-González ◽  
Lorenzo Rubio-Arjona ◽  
Juan Ribera Reig-Pascual ◽  
...  
Keyword(s):  
Path Loss ◽  
Separation Distance ◽  
Line Of Sight ◽  
Indoor Environments ◽  
University Campus ◽  
Laboratory Environment ◽  
Regression Techniques ◽  
Reference Distance ◽  
Loss Models ◽  
And Performance

The objective of this work is to propose experimental path loss propagation models for communication channels in indoor environments. In this sense, an experimental path loss characterization has been achieved, according to the measurements campaign carried out in a typical scenario of a university campus. These narrowband measurements were collected in the laboratory environment at 3.7 GHz in line-of-sight (LOS) condition. Also, these measurements were carried out at night to simulate stationary channel conditions. Thus, the results obtained show the values of the parameters of the close-in (CI) free space reference distance and floating-intercept (FI) path loss models, in terms of the transmitter and receiver separation distance. It should be noted that these values of the path loss models have been extracted applying linear regression techniques to the measured data. Also, these values agree with the path loss exponent values presented by other researchers in similar scenarios. The path loss behavior can be described with the implementation of these models. However, more measurement campaigns are needed to improve the understanding of propagation channel features, as well as to obtain better precision in the results obtained. This, in order to optimize the deployment and performance of next fifth-generation (5G) networks that combine indoor environments to offer their services and applications.

scholarly journals Survey of Millimeter-Wave Propagation Measurements and Models in Indoor Environments

Electronics ◽  
2021 ◽  
Vol 10 (14) ◽  
pp. 1653
Author(s):  
Ahmed Al-Saman ◽  
Michael Cheffena ◽  
Olakunle Elijah ◽  
Yousef A. Al-Gumaei ◽  
Sharul Kamal Abdul Rahim ◽  
...  
Keyword(s):  
Millimeter Wave ◽  
Measurement Techniques ◽  
Path Loss ◽  
Delay Spread ◽  
Indoor Environments ◽  
Future Trends ◽  
Signal Loss ◽  
Indoor Wireless ◽  
The Future ◽  
Future Demands

The millimeter-wave (mmWave) is expected to deliver a huge bandwidth to address the future demands for higher data rate transmissions. However, one of the major challenges in the mmWave band is the increase in signal loss as the operating frequency increases. This has attracted several research interests both from academia and the industry for indoor and outdoor mmWave operations. This paper focuses on the works that have been carried out in the study of the mmWave channel measurement in indoor environments. A survey of the measurement techniques, prominent path loss models, analysis of path loss and delay spread for mmWave in different indoor environments is presented. This covers the mmWave frequencies from 28 GHz to 100 GHz that have been considered in the last two decades. In addition, the possible future trends for the mmWave indoor propagation studies and measurements have been discussed. These include the critical indoor environment, the roles of artificial intelligence, channel characterization for indoor devices, reconfigurable intelligent surfaces, and mmWave for 6G systems. This survey can help engineers and researchers to plan, design, and optimize reliable 5G wireless indoor networks. It will also motivate the researchers and engineering communities towards finding a better outcome in the future trends of the mmWave indoor wireless network for 6G systems and beyond.

scholarly journals Topology Control Using Distributed Power Management Algorithm for Mobile Ad Hoc Networks

2009 ◽  
Vol 5 (4) ◽  
pp. 128
Author(s):  
Nuraj Pradhan ◽  
Tarek Saadawi
Keyword(s):  
Ad Hoc ◽  
Dynamic Network ◽  
Path Loss ◽  
Packet Delay ◽  
Management Algorithm ◽  
Physical Channel ◽  
Strongly Connected ◽  
Node Connectivity ◽  
Hoc Networks ◽  
Log Normal

In order to be strongly connected in the network, a node may increase its power indiscriminately causing interference. Since interference is one of the major problems in wireless network, the proposed algorithm will co-operatively reduce inter-node interference in the network. Further, uni-directional links are a major source of interference as most of the routing protocol only utilizes bi-directional links. The algorithm will attempt to prevent such links or if required convert them into bi-directional links. We will show that the proposed algorithm provides strongly connected and more reliable network over dynamic physical channel modeled by log-distance path loss model, log-normal shadowing model and rayleigh fading model. It stabilizes node connectivity over the dynamic network and environment and even, to a certain extent, prevent node from being completely disconnected from the network. For the selected simulation environment, we will show that the proposed algorithm provides a shorter packet delay, improves the network throughput by as much as 37%, decreases the routing overhead and reduces interference.

scholarly journals Smart Skin Envelope

2011 ◽  
Author(s):  
Rosa Romano
Keyword(s):  
State Of The Art ◽  
Innovation Process ◽  
Research Programme ◽  
Energy Performance ◽  
Indoor Environments ◽  
Performance Parameters ◽  
Skin Envelope ◽  
And Performance ◽  
Definition Of ◽  
Smart Skin

The Smart Skin Envelope research analyses the recent revolution that has taken place in the sector of planning and production of smart skin components, made up of dynamic layers. The aim is to identify the technological, functional, qualitative and performance parameters that guide the decisions of the actors in the innovation process. It explores the factors that drive them to develop solutions and proposals designed to transform the envelope of the building from a static to a dynamic element, featuring interoperable components that can interact with the input from the outdoor and indoor environments, in relation to which the smart skin acts as a system of boundary and delimitation. The proposed research programme explores in particular the sector of Smart Envelopes, setting as its priority objective the identification and definition of the energy performance, both through analysis of the state of the art and through the development of a facade component that is dynamic in terms of the adaptive variability of its performance.

scholarly journals Optimizations for Energy Efficiency in Software-Defined Wireless Sensor Networks

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4779
Author(s):  
Sorin Buzura ◽  
Bogdan Iancu ◽  
Vasile Dadarlat ◽  
Adrian Peculea ◽  
Emil Cebuc
Keyword(s):  
Energy Efficiency ◽  
Network Performance ◽  
Wireless Sensor ◽  
Management Approach ◽  
Control Plane ◽  
Data Broadcast ◽  
Data Packets ◽  
Similar Work ◽  
And Performance ◽  
The Individual

Software-defined wireless sensor networking (SDWSN) is an emerging networking architecture which is envisioned to become the main enabler for the internet of things (IoT). In this architecture, the sensors plane is managed by a control plane. With this separation, the network management is facilitated, and performance is improved in dynamic environments. One of the main issues a sensor environment is facing is the limited lifetime of network devices influenced by high levels of energy consumption. The current work proposes a system design which aims to improve the energy efficiency in an SDWSN by combining the concepts of content awareness and adaptive data broadcast. The purpose is to increase the sensors’ lifespan by reducing the number of generated data packets in the resource-constrained sensors plane of the network. The system has a distributed management approach, with content awareness being implemented at the individual programmable sensor level and the adaptive data broadcast being performed in the control plane. Several simulations were run on historical weather and the results show a significant decrease in network traffic. Compared to similar work in this area which focuses on improving energy efficiency with complex algorithms for routing, clustering, or caching, the current proposal employs simple computing procedures on each network device with a high impact on the overall network performance.

scholarly journals Utilization of an OLED-Based VLC System in Office, Corridor, and Semi-Open Corridor Environments

Sensors ◽  
2020 ◽  
Vol 20 (23) ◽  
pp. 6869
Author(s):  
Zahra Nazari Chaleshtori ◽  
Zabih Ghassemlooy ◽  
Hossien B. Eldeeb ◽  
Murat Uysal ◽  
Stanislav Zvanovec
Keyword(s):  
Indoor Localization ◽  
Low Cost ◽  
Flexible Substrate ◽  
Path Loss ◽  
Visual Display ◽  
Outer Wall ◽  
Channel Gain ◽  
Delay Spread ◽  
Indoor Environments ◽  
Visible Light Communications

Organic light emitting diodes (OLEDs) have recently received growing interest for their merits as soft light and large panels at a low cost for the use in public places such as airports, shopping centers, offices, and train or bus stations. Moreover, the flexible substrate-based OLEDs provide an attractive feature of having curved or rolled lighting sources for the use in wearable devices and display panels. This technology can be implemented in visible light communications (VLC) for several applications such as visual display, data communications, and indoor localization. This article aims to investigate the use of flexible OLED-based VLC in indoor environments (i.e., office, corridor and semi-open corridor in shopping malls). We derive a two-term power series model to be match with the root-mean-square delay spread and optical path loss (OPL). We show that, for OLED positioned on outer-wall of shops, the channel gain is enhanced in contrast to them being positioned on the inner-wall. Moreover, the channel gain in empty environments is higher compare with the furnished rooms. We show that, the OPL for a 10 m link span are lower by 4.4 and 6.1 dB for the empty and semi-open corridors compared with the furnished rooms, when OLED is positioned on outer-wall of shops. Moreover, the channel gain in the corridor is higher compared with the semi-open corridor. We also show that, in furnished and semi-open corridors the OPL values are 55.6 and 57.2 dB at the center of corridor increasing to 87.6 and 90.7 dB at 20 m, respectively, when OLED is positioned on outer-wall of shops.

EXPRESS: Gender (Still) Matters in Business School

2020 ◽  
pp. 002224372097236
Author(s):  
Aradhna Krishna ◽  
A. Yeşim Orhun
Keyword(s):  
Standard Deviation ◽  
Gender Stereotypes ◽  
Business School ◽  
Role Models ◽  
Gender Performance ◽  
Performance Expectations ◽  
Increase Student Achievement ◽  
Administrative Dataset ◽  
Academic Aptitude ◽  
And Performance

This research documents systematic gender performance differences (GPD) at a top business school using a unique administrative dataset and survey of students. The findings show that women’s grades are 11% of a standard deviation lower in quantitative courses than those of men with similar academic aptitude and demographics, and men’s grades are 23% of a standard deviation lower in nonquantitative courses than those of comparable women. The authors discuss and test for different reasons for this finding. They show that a female instructor significantly cuts down GPD for quantitative courses by raising the grades of women. In addition, female instructors increase women’s interest and performance expectations in these courses and are perceived as role models by their female students. These results provide support for a gender stereotype process for GPD and show that faculty can serve as powerful exemplars to challenge gender stereotypes and increase student achievement. The authors discuss several important implications of these findings for business schools and for society.

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