An Extended-AMATA Indoor Propagation Model for GSM 900/1800 MHz and Wi-Fi 2.4 GHz Frequencies

In a previous article, we reported on a novel indoor propagation model; we called the AMATA model, which we applied at 900 MHz and 2.4 GHz frequencies. The model could be applied at both GSM and wireless LAN frequencies. The developed formula merits, on its own, as a novel fourth power effective attenuation equation, which relies on the number of wall separations within the floor. This paper reports an extended-AMATA indoor propagation model that generally describes university and office type buildings. A sample of four different multi-floor building structures that have a stone block type outer wall was chosen. Those flat roofed, stone built, multi floor buildings are very common, not only in Palestine, but probably in vast areas in the Middle East region. The new model benefits over the previous one, applied at 900 MHz, in that it can be extended to cellular base-stations, transmitting at 1800 MHz frequency and outdoor Wi-Fi basestations, as opposed to indoor access points, transmitting at 2.4 GHz. The work is of paramount importance to cellular and Wi-Fi network operators, transmitting at 900/1800 MHz and 2.4 GHz frequency bands. Our new model can be applied with a high confidence level to buildings, similar to the sample of buildings, we measured.     

Diagnosis of Wireless Sensor Networks in Presence of Permanent and Intermittent Faults

In this paper we consider the problem of distributed fault diagnosis in Wireless Sensor Networks (WSNs). The proposed Fault Diagnosis Algorithm (FDA) aims to handle both permanent and intermittent faults. The sensor nodes with permanent communication faults can be diagnosed by using the conventional time-out mechanism. In contrast, it is difficult to detect intermittent faults due to their inherent unpredictable behavior. The FDA is based on the comparison of sensor measurements and residual energy values of neighboring sensor nodes, exploiting their spatial correlations. To handle intermittent faults, the comparisons are made for \(r\) rounds. Two special cases of intermittent faults are considered: one, when an intermittently faulty node sends similar sensor measurement and similar residual energy value to some of its neighbors in all \(r\) rounds; another, when it sends these values, either or both of which deviates significantly from that of some neighbors in all \(r\) rounds. Through extensive simulation and analysis, the proposed scheme is proved to be correct, complete, and efficient to handle intermittent faults and hence, well suited for WSNs.     

Review of Wireless Personal Communications Radio Propagation Models in High Altitude Mountainous Areas at 2.6 GHz

This paper presents five commonly used radio propagation models (RPMs) which are suitable for the prediction of path loss in macrocell environments of LTE wireless communication systems. These RPMs’ application in high altitude mountainous areas networks (HAMANETs) environment requires further validation and studies. Through using the measured path loss in the HAMANETs at 2.6 GHz to calculate the predicted value of the five RPMs and the measured value’s mean error (ME), root mean square error, and error standard deviation (ESTD), we verified the predicted value of the SPM model that is closer to the actual measurement. On this basis, the empirical propagation model in HAMANETs environment is corrected. When correcting, a method to calculate base station’s effective antenna height and propagation distance is provided by using the altitude above sea level data. This method can reduce the error that the mountainous areas are simplified to the flat-terrain in the existed propagation models. A linear least square method is used to calculate the optimal propagation model. Finally, the ME is the smallest, and the ESTD is less than 8 dB, which indicate that the corrected propagation model is more suitable for the actual environmental path loss’s prediction. The results show that the path loss factor of the test area is about 65 dB, including the influence of the high altitude, mountains, vegetation, and air humidity in HAMANETs environment. The study results can provide useful advice to the evaluation and verification of personal wireless communications in the HAMANETs. Furthermore, using the correction method proposed in this paper can correct propagation models suitable for the different propagation environments to improve the accuracy and efficiency of wireless network optimization.     

An Energy-Efficient Routing and Self-Organization Algorithm in Wireless Sensor Networks

1IntroductionAs the development of MEMStechnology,the microsensors whichintegrate manyfunctions such as sensing,signal processing and communication have been widelyused[1]. Wireless Sensor Network ( WSN) is construct-ed with hundreds to thousands of sensors and one ormore SINKs .Sensors can sense (monitor) many physi-cal signals such as sound,light ,electronics ,tempera-ture and humidity of the objects in a given region[2 ~3].Sensors transfer these signalsinto sensing data and sendsensin…     

Wireless Regional Area Networks and Cognitive Radio 2

The IEEE 802.22 Working Group hasbeen formed in November 2004with the task ofdeveloping astandard for the Wireless RegionalArea Network (WRAN) based onCognitive Radio (CR) technologies. Thestandard includes PhysicalLayer (PHY)and Media Access Control(MAC), usingthe already allocated fallow spectrums tobroadcast TVwith no interference. TheWRAN employs CR technologies tosense and estimate the televisionfrequencies and uses the dynamicspectrum management to find andallocate fallow …     

Multi-Hop Wireless Backhaul Networks above 10 GHz: Connectivity and Critical Density Evaluation

Microwave links are the obvious mobile backhauling solution for many mobile operators. Multi-hops are likely to be necessary in order to ensure connectivity for mobile backhaul solutions. The subject of the present paper is the evaluation of the connectivity of wireless multi-hop backhaul networks assuming high frequency transmissions among the relays. A novel analytical physical propagation and engineering model is presented for the calculation of the connectivity of wireless multi-hop networks that appropriate for operating frequencies above 10 GHz. Assuming equal power transmissions from every node and a random spatial node distribution following the homogeneous Poisson process, we calculate the node isolation probability. Furthermore, we calculate the minimum required node density in order to keep the backhaul network almost connected. The sensitivity of the isolation probability and of the minimum node density on frequency of operation, transmission power and climatic conditions is also investigated. Some useful conclusions are drawn.     

A Tracking-Based Target Locating Algorithm in Wireless Sensor Networks

1　IntroductionAwirelesssensornetworkisusuallycomposedofhundredsorthousandsofsensorsequippedwithcomputation ,sensingandcommunicationdevices,whicharecoordinatedinadistributedmodeinordertomonitoracertaingeographicalregionandcollectinformationontheirsurroundings[1 ] .Thecollecteddataisthenusedtoanswervariousqueries.RecentadvancesinMEMS ,wirelesscommunications,anddigitalelectronicshavemadepossiblethecheapandfastdeploymentofsensornetworks[2 ] .Suchadhoc,self organizingsensornetworksarereceivingin…     

An Indoor Propagation Model Based on a Novel Multi Wall Attenuation Loss Formula at Frequencies 900 MHz and 2.4 GHz

This paper describes an indoor propagation model pertaining to a sample of six different multi-floor building structures that have a stone block type outer wall and are generally described as university, hospital and office type buildings. Those flat roofed, stone built, multi floor buildings are very common, not only in Palestine, but probably in vast areas in the Middle East region. The goal is to come up with a relatively general model that would be both reliable and representative to a wider sample of multi-floor buildings, falling under a similar building structure classification. The improved model; we name the AMATA model, lends itself to its generalization for the GSM and wireless LAN frequencies as well as the developed multiwall effective attenuation fourth power nonlinear equation that solely relies on the number of wall separations within the floor. A clear improvement in the standard deviation of the mean path loss resulted in comparison to the well known indoor ITU path loss model. Our model can be applied with a high confidence level to the wider range of buildings similar to the classification type of the building structure sample, we conducted measurements upon.     

P-Zone： Connectivity-based Packet Path Tracing in Wireless Sensor Networks

In large-scale Wireless sensor networks （WSNs）, the network status is complex and unpredictable, which brings great challenges to practical network design and management. Tracing the route path of each data packet in the network is an important way to observe network behaviors and understand network dynamics. However, tracing the full route path of each packet could be highly challenging, due to the hard resource con- straint in WSNs. Our previous work proposes a hash-based path tracing mechanism, and leverages network connectivity and node locations to reduce the computational complexity. However, the node locations may be unavailable in some scenarios. In this work, we further propose a location-free enhancement to the hash-based path tracing mechanism, called P-Zone. P-Zone requires only network connectivity information to reduce the computational complexity. Theoretical analysis and practical simulations are conducted to evaluate the effectiveness and performance of our design. The results indicate that P-Zone can significantly reduce the computational complexity of the hashbased path tracing mechanism, while effectively tracing the full route path of each packet in the network in a real-time manner, and outperforms the state-of-the-art methods.     

Wireless Regional Area Networks and Cognitive Radio(1)

1 Wireless Regional Area Networks (WRANs) and IEEE802.22 The advent of information era has been followed by all of the more extensive application of wireless services and devices, such asmobile communications, radio broadcast, and television. All these are exhausting spectrum resource andmaking it more precious than land andmineralresources. Nowadays,transmitters and receivers forcommunication systems needcertification from government to enter acommunication network. Therefore, thereare b…     

Channel Sounding System for MM-Wave Bands and Characterization of Indoor Propagation at 28 GHz

The aim of this work is to present a vector network analyzer based channel sounding system capable of performing measurements in the range from 2 to 50 GHz. Further, this paper describes an indoor measurement campaign performed at 26–30 GHz. The sounding system is capable of receiving two channels and transmitting one. Using this feature a channel measurement has been performed using both a directional horn antenna and a virtual uniform circular array (UCA) at the same time. This allows for comparative studies of measured channels with two different antennas in a simultaneous way. The measurement has been conducted with 42 measurement positions distributed along a 10 m long path through an indoor laboratory environment. The transmitter was positioned such that measurements were conducted both in line-of-sight and non-line-of-sight scenarios. The measurements showed good agreement between the measurement data collected with the horn antenna and the data collected with the UCA. The propagation environment was found to be sparse both in delay and angular domain for the given scenario. Based on the performed measurement campaign together with validation measurements of the system stability, it is found that the system works as expected.     

Routing Protocol with Optimal Location of Aggregation Point in Wireless Sensor Networks

1IntroductionAdvances in the miniaturization of MicroElectronicand Mechanical Structures(MEMS)haveledto batterypowered sensor nodes that have sensing,communica-tion,and processing capabilities[1~4].Sensor networkshave emerged as an indispensable and i mpo…     

An Authenticated Identity-Based Key Establishment and Encryption Scheme for Wireless Sensor Networks

1Introduction Wirelesscommunicationhasbeenahotissuesince1990.includingAdhocandwirelesssensornetworks,etc.Especially,WirelessSensorNetwork(WSN).Whichhasreceivedconsiderableattentionduringlast decade[1-2].Ithasbeendevelopedforawidevarietyof applications,inc…     

Distributed and Energy Efficient Self-Organization for On–Off Wireless Sensor Networks

In this paper, we utilize clustering to achieve energy efficiency for the on–off wireless sensor network, whose member nodes alternate between active and inactive states. In the proposed Distributed and Energy Efficient Self Organization (DEESO) scheme, the head election is adjusted adaptively to the remaining battery levels of local active nodes, which is a completely distributed approach compared to LEACH that relying on other routing schemes to access global information. Furthermore, we apply the Adaptive Channel Assignment (ACA) to address the on-off topology changes. Simulation results show that DEESO delivers 184% amount of data to the base station as LEACH for the same amount of energy consumption and the effective network lifetime is extended by around 50%.     

Multi-constrained Max–Min Fair Resource Allocation in Multi-channel Wireless Sensor Networks

Wireless Personal Communications - Recent rich applications for the Internet of Things are demanding large bandwidth for communication which can cause congestion within multi-hop wireless sensor...     

Is Localization of Wireless Sensor Networks in Irregular Fields a Challenge?

Wireless Personal Communications - Wireless sensor networks have been considered as an emerging technology for numerous applications of cyber-physical systems. These applications often require the...     

An Energy-Aware Geographical Forwarding Protocol Utilizing Adaptive Sleeping in Wireless Sensor Networks

1IntroductionA wireless sensor network is the combination of thephysical world and information technology.Sensor net-works can contain hundreds of thousands of cheap sens-ing nodes that work in the formof Ad Hoc networks,monitoring the environment andrepo…     

Unequal Clustering Protocols for Wireless Sensor Networks—Taxonomy,Comparison and Simulation

Wireless Sensor Network (WSN) consists of randomly distributed sensor nodes which can collect, process, route and transmit data from their respective environment. Most of the research on WSN is oriented towards optimizing utilization of finite resources of Sensor Nodes to increase the overall network operative time. Recent literature on WSNs reveals that hierarchical routing unequal clustering methodologies are gaining popularity due to energy efficiency, load balancing and scalability. In literature, numerous surveys on clustering methodologies are available which address different equal clustering methods. The unequal clustering protocols, which have their own attributes viz. balance load distribution, hot spot mitigation and energy efficiency, are comparatively less explored. This motivated us to undertake the present study on the taxonomy, comparison and simulation analysis of different methodologies pertaining to less explored unequal clustering protocols. Our base metrics for comparison of different unequal clustering protocols are scalability, energy efficiency & load balancing capability of the resulting network. A comprehensive discussion has also been presented to highlight the various advantages and disadvantages of different unequal clustering protocols. Further, we have summarized the study of unequal clustering protocols in the tabular form.