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In this article, we analyze the performance evaluation of WiFi technology in conformance with IEEE 802.11b/n/ac standards and Wireless Distribution System (WDS) for indoor environments with and without obstacles. We present different scenarios by varying the distance between transmitter and receiver. We analyzed the performance of the network by using the intrusive technique of traffic injection with...
The correct classification of several types of volcanic events can be used to determine the intrinsic behavior of a volcano. This information could be useful to provide an early alarm in the case of imminent volcanic activity. Therefore, finding an efficient algorithm capable of identifying seismic activity can be beneficial for this purpose. In such sense, this work evaluates several machine learning...
This work evaluates the performance of TCP Protocol new algorithm on a wide-area wireless link in order to optimize it and compare the results. To this purpose, is proposed an optimization and QoS solution in order to improve the TCP new algorithm performance. Also a WWAN point to point link was designed and implemented and the optimization solution was configured on it using dedicated hardware. Finally,...
In this paper we evaluate the performance of the new algorithm of the TCP protocol for a long distance wireless link in the Galapagos Islands. In order to achieve this goal, it has been started from a study of different standards and tools for this project, besides of the amendments to the TCP protocol for wireless environments. Finally, the network was implemented and preceded to inject traffic to...
Most of phenomena in different areas of telecommunications engineering can not be represented by linear models, as the case of satellite systems. Its main problem is the limitation of power due to the wireless long distance link. This paper proposes to use a model by using Volterra series on adaptive filters Least Mean Square (LMS) and Recursive Least Squares (RLS), in order to compensate the signal...
This article describes the performance evaluation of a new wireless TCP algorithm in real environments, in order to identify the advantages and disadvantages of its operation. We evaluate the proposed wireless TCP algorithm with respect to generic TCP, considering an intrusive technique by using traffic injection. These tests were performed over point-to-point WiFi and WiMAX links in out-door and...
Augmented Reality complements the perception and interaction with the real world and allows the end-user to be in an augmented real environment with additional information generated by the computer. This work is divided into two main parts: First, we studied the digital image processing used in the detection and recognition markers, the methods for creating bookmarks with high contrast by generating...
Usage of wireless networks is rising in popularity. In this setting different kinds of networks for indoor environments, such as Ad-Hoc, IEEE 802.11b (Wi-Fi) and Wireless Distribution System (WDS) has been developed. In this paper, an analysis of Quality of Service (QoS) has been made for each network in order to verify the values of bit rate, delay, jitter and packet loss. For performance comparison...
This paper presents a study to select the most relevant features for classification of seismic signals obtained from the Cotopaxi Volcano, in the time and frequency domain. Fourier and Wavelet transform were used in the analysis. A total of 79 different features were used for the study. Feature selection was performed by CART by using Gini, Standard Deviation, Twoing Rule, Gram-Schmidt, and Interaction...
The evolution of wireless networks and the low cost of WiFi technology, have enabled a promising scenario for deployment of these kind of networks in rural areas, as an effective alternative to interconnect distanced sites above tens kilometers. This work presents the results of the performance evaluation of a network with WiLD technology, based on simulation and a deployment in the Andean region...
A volcano monitoring system plays a key role for launching emergency early warning, and the use of alternative technologies have proven their effectiveness in this setting, which is the case of wireless sensor networks. For surveillance systems, the real-time requirement is mandatory due to the need for immediate access to the signals derived from a natural disaster where the goal is safeguarding...
This study proposes a new method to characterize volcanic seismic events based on classic spectral and maximum entropy estimators. Events of interest are detected in the time domains by a new structure of sequential robust detection obtained using autoregressive spectral analysis. Classical power spectral density analysis is then used to define spectral features for each type of seismic events of...
This work presents a performance analysis among different propagation models to estimate path loss on the wireless channel for communication systems in conformance with IEEE 802.16-2009 WirelessMAN Fixed OFDM. We developed and implemented a simulator using Matlab®, this simulator considers the channel losses and reflects their effects on the physical layer. The system implementation considers different...
Since the year 2007, Escuela Politécnica del Ejército has been carrying out lab and field tests to evaluate the performance of current digital television systems. ISDB-Tb is the Japanese with Brazilian modifications digital terrestrial television standard adopted by Ecuadorian Government, which is able to transmit multiple television programs with interactive applications and high definition contents...
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