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The development of wireless technologies led to the birth of numerical dosimetry for non-ionizing radiation. This paper validates two statistical methods to evaluate SAR for cylindrical body models. The first method is Monte Carlo method in a stochastic physical model of propagation, the second method is an analytical method based on Uncorrelated Scattering assumption. These methods allow a statistical...
As an integral part of reliable communication in wireless networks, effective link estimation is essential for routing protocols. However, due to the dynamic nature of wireless channels, accurate link quality estimation remains a challenging task. In this paper, we propose 4C, a novel link estimator that applies link quality prediction along with link estimation. Our approach is data-driven and consists...
For designing a wireless network, field test is mostly preferred for researchers to test and evaluate the system performance. However, it is expensive for field constructions and thus it is not affordable for most researchers. Software simulation is another option. However, the results by simulation may be undesirably biased away the true. This paper proposes a new method to trade off between resource...
This paper presents classification of the related methods used in wireless channel modeling, including mathematical modeling, stochastic modeling, Ray-tracing, Ray-launching, FDTD. The comparison between the empirical models and the deterministic models helps to distinguish the application situation of each channel model. Therefore, the study will promote the wireless channel models development, and...
In this paper, we present AEROMAN (Architecture to Evaluate Routing Protocols for Multi-hop Ad-hoc Networks) which is designed and implemented for evaluation of routing protocols for multi-hop wireless networks. AEROMAN uses QOMET, a wireless link emulation tool, to compute parameters of wireless links, such as bandwidth, delay, packet loss rate, in contention-free conditions. In order to take into...
In this paper, we summarized all kinds of wireless MIMO channel and analyzed their time space model of MIMO channel model. In order to evaluate the MIMO effectively, a new time delay MIMO model was proposed. Based on 3GPP TR25.996 protocol, a new method for simulation time delay MIMO channel was proposed according to average arrival angle, extended angle of signal and structure of transceiver antennas...
In RFID literature, most “privacy-preserving” protocols require the reader to search all tags in the system in order to identify a single tag. In another class of protocols, the search complexity is reduced to be logarithmic in the number of tags, but it comes with two major drawbacks: it requires a large communication overhead over the fragile wireless channel, and the compromise of a tag in the...
Wireless network simulation is used for research because of its simplicity and repeatability. While simple radio propagation models are evaluated quickly and are suitable for simple scenarios, sophisticated models can handle more complex environments and provide better accuracy. However, the cost of higher accuracy is slower execution speed. This paper describes experiments that validate ray-tracing...
The characterization of the wireless channel on board a cruise ship is considered by means of frequency domain measurements of received power and propagation attenuation. This electromagnetic environment is rather new and is characterized by abundance of reflecting surfaces and diffracting elements, so that a significant difference with respect to more common residential and office environments has...
In wireless channels, multipath fading and shadowing occur simultaneously leading to the phenomenon referred to as composite fading. The use of the Nakagami probability density function (PDF) to model multipath fading and the Gamma PDF to model shadowing has led to the generalized-K model for composite fading. However, further derivations using the generalized K PDF are quite involved due to the computational...
This paper proposes and discusses the modification and extension of the present Wireless Local Area Network (WLAN) to use it for communication system to enhance its performance in the Medium Access Control (MAC) layer. The Medium Access Control (MAC) protocol is the primary element determining how efficiently the limited communication bandwidth of the wireless channel is shared in a Wireless Local...
A real-time simulator for vehicle-to-vehicle (V2V) communication scenarios with a new integration method for the wireless network simulator NS-2 and the vehicular and traffic simulator (VATSIM) is introduced. Vehicular micro traffic networks with multiple intersections and vehicles using 802.11p communication are simulated and a collision warning system including a driver response model is investigated...
A geometric model that describes a multipath propagation for a fixed wireless communication system between a high altitude platform and a fixed terrestrial user is presented. The model describes the propagation of the reflected signals that are able to reach the receiver as a consequence of all the scatterers located inside the system coverage area. The establishment of a particular geometry characterizing...
In this paper, a new method to model and simulate a wireless communication system based on system on chip design methodology will be presented. The network performance effected by the amount of detail in the simulation model. Hence there is a need to develop suitable abstractions that maintain the accuracy of the simulation while keeping the computational resource requirements low. The integration...
Opportunistic spectrum access, where cognitive radio devices detect available unused radio channels and exploit them for communication, avoiding collisions with existing users of the channels, is a central topic of research for future wireless communication. When each device has limited resources to sense which channels are available, the task becomes a reinforcement learning problem that has been...
Focusing on large-scale vehicular ad-hoc networks (VANETs), we consider the interplay between single-hop channel models and large-scale network connectivity. Building on a realistic urban traffic simulator, we progressively increase the sophistication of the wireless link while evaluating the resulting connectivity profiles. Our results show that large-scale VANET connectivity, whose understanding...
This paper presents a simulation environment, based on the parallel finite-difference time-domain (FDTD) method, for subject-specific radio channel modeling in wireless body sensor networks (WBSNs). The simulation environment takes into account realistic antenna radiation patterns in channel modeling to analyze their effects on WBSNs. The proposed simulation tool is applied to a study of body communication...
A stochastic 2times2 MIMO wideband channel modelling method is presented. This channel model uses tapped delay lines (TDL) to model the subchannels and a single channel spatial correlation matrix to introduce the statistical dependence. This model represents a novel simplification with respect to other wideband MIMO models. The channel models obtained from this method are accurate and computationally...
The purpose of this paper is to introduce a model intended to capture the behavior of the wireless channel at time scales which are related to packet transmission times. In this approach it is assumed that the prime factor affecting data rate selection is the path attenuation. We model the wireless channel using a multistate stochastic process where each state corresponds to the nominal data rate...
Wireless channel emulators are important tools for testing radio devices, especially in mobile environments. Wireless network emulators give the same accuracy and control for testing radio network systems that traditional channel emulators give to point to point radio links. Network emulators require many more independent channels than traditional channel emulators. This problem is particularly challenging...
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