Homero Toral, D. T. Román, C. Hernández, L. E. Vargas
{"title":"Self-Similarity, Packet Loss, Jitter, and Packet Size: Empirical Relationships for VoIP","authors":"Homero Toral, D. T. Román, C. Hernández, L. E. Vargas","doi":"10.1109/CONIELECOMP.2008.20","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.20","url":null,"abstract":"In this paper, as result of a thorough self-similar analysis we found self-similar characteristics in different sets of VoIP Jitter traces, with short range and long range statistical dependence (i.e. LRD and SRD). We used the E-model's R factor for estimating the QoS perceived by the end user, and we established the following empirical relationships: when the values of the estimated Hurst parameter were lower than 0.5 (SRD) the analyzed performance metrics, i.e. average packet loss rate and average Jitter, maintained stable values and acceptable QoS levels. While the values of the estimated Hurst parameter were greater than 0.5 (LRD) the variability of the analyzed performance metrics were increased and the QoS levels diminished. The other empirical relationship shown in this article refers to the payload size for each CODEC type used, the larger the payload size was, the higher the average Jitter became.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128068564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. R. Domínguez, D. T. Román, J. Dehesa, D. M. Rodríguez
{"title":"Cauchy Distribution for Jitter in IP Networks","authors":"L. R. Domínguez, D. T. Román, J. Dehesa, D. M. Rodríguez","doi":"10.1109/CONIELECOMP.2008.39","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.39","url":null,"abstract":"In many real-time applications the quality of service (QoS) is dominated by jitter. In this paper RTT (round trip time) measurements were collected in order to find a probabilistic jitter model. From collected measurements the tail index was close to unit, this relates us to Cauchy's distribution. In this paper we show that the jitter has direct influence in the network performance. The purpose of this paper is to show how jitter dispersion affects the QoS in some applications.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116478153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Moreno-García, C. Guerra, J. M. D. L. Rosa-Vázquez
{"title":"Spectrometer to Measure the Steady-State Fluorescence Emitted by Liquid and Solid Samples","authors":"E. Moreno-García, C. Guerra, J. M. D. L. Rosa-Vázquez","doi":"10.1109/CONIELECOMP.2008.23","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.23","url":null,"abstract":"Fluorescence methods are being widely used in the measurement of species concentrations in gases, liquids and solids. Fluorescence is spontaneous emission from atoms or molecules that have been excited by light. Here we report some measurements of steady-state fluorescence emitted by samples of liquids (Antifreeze, detergent, soapy water), solids (colored bond papers) and organic compounds (vegetables and fruits). The measurements were performed with a home made spectrometer from 200 to 800 nm. This consists of an excitation light source, a bifurcate optical fiber probe for high delivery and collection of light, a monochromator with a high sensitivity PMT, a DAQ board, and a lap-top computer. The spectrometer is controlled by a program written in the graphical language G of the LabVIEW 7.1. For purposes of comparison we use two light sources: an UV led (375 nm) and a high luminescence blue led (447 nm).","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132299869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of 2 Stages Ring Oscillators Applying Local Networks of Feedback","authors":"D. Colin, A. Díaz-Sánchez, M. L. Aranda","doi":"10.1109/CONIELECOMP.2008.11","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.11","url":null,"abstract":"This paper presents the design of 2 stages ring oscillator voltage controlled (VCO), through phase degeneration of the load symmetrical cell, using local feedback networks, these feedback networks are implemented using the quasi- floating gate transistors (QFGT's), in order to upset the circuit. The design was done in technology AMIS CMOS 0.35 mu.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125263431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Lobato-Morales, A. Corona‐Chavez, L. G. Guerrero-Ojeda
{"title":"Omnidirectional Planar Antennas for PCS-Band Applications Using Fiberglass Substrates","authors":"H. Lobato-Morales, A. Corona‐Chavez, L. G. Guerrero-Ojeda","doi":"10.1109/CONIELECOMP.2008.6","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.6","url":null,"abstract":"The design, construction and characterization of planar antennas implemented using fiberglass substrate is presented. For PCS-band frequencies (1.9 GHz), planar antennas are usually constructed of copper films on low- permittivity low loss substrates such as Duroid. Duroid improves the antenna efficiency due to its uniform structure for microwave designs, but its main disadvantage is its high cost. Good antenna performance can be achieved using other substrates, like fiberglass, that is one of the most common materials to construct DC printed circuit boards. Dipoles, patches and collinear arrays are implemented using fiberglass substrates achieving good performance over PCS band. A directional wideband Vivaldi antenna is designed and implemented using the same fiberglass substrate for gain measurements.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126746569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hurst Parameter Estimator Based on a Decomposition by Aggregated Series","authors":"L. Estrada, D. Torres, J. Ramirez","doi":"10.1109/CONIELECOMP.2008.19","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.19","url":null,"abstract":"In this work, a comparison of three estimators of the Hurst parameter is presented: the classical variance-based method and two new estimators based on an orthogonal decomposition (that can be achieved by aggregated series or by using Haar filters) and that use, respectively, a weighted and a non-weighted linear regression. These three estimators were applied to a set of synthetic fGN traces. The analyses showed that the variance method and the estimator that uses non-weighted linear regression underestimate the theoretical value of H, while the third estimator, decomposition-based, that uses a weighted linear regression, shows an excellent behavior. This estimator presented a bias nearer to zero and the lowest standard error when applied to fGN traces for lengths from 1024 to 1048576 samples. The presented decomposition can be extended to study the frequency information of the time series, by obtaining what we call Hurst spectrum, and to generate time series that comply the definitions of self-similar time series.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"65 Suppl 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130022451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Germán Ardul Muñoz Hernández, G. Tejeda-Munoz, A. F. Tellez, C. Gracios-Marin, A. Díaz-Sánchez
{"title":"Implication of Electric Noise in the ACORDE Front-End Electronics of the ALICE Experiment","authors":"Germán Ardul Muñoz Hernández, G. Tejeda-Munoz, A. F. Tellez, C. Gracios-Marin, A. Díaz-Sánchez","doi":"10.1109/CONIELECOMP.2008.9","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.9","url":null,"abstract":"In this work is presented a noise analyse of the Front- Electronics of the ACORDE detector. ACORDE is one of the detectors that will be employed on the ALICE project. Low pass filters are applied in order to reduce the noise on the output signal. The results of using filters allow us to consider it in the next upgrade of the ACORDE electronics.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122063484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. L. Rincon, J. Vázquez-González, A. Aguilera-Fernandez, Juan Antonio Navarro Martínez, A. Z. Escudero-Uribe
{"title":"Fast Fourier Transform Adjusted into 8 Bit Format for Instrumentation Purposes","authors":"A. L. Rincon, J. Vázquez-González, A. Aguilera-Fernandez, Juan Antonio Navarro Martínez, A. Z. Escudero-Uribe","doi":"10.1109/CONIELECOMP.2008.30","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.30","url":null,"abstract":"The present article shows an application of Fourier analysis for signal processing. The main characteristic of the project is that the iterative fast Fourier transform radix-2 decimation-in-frequency algorithm had to be adjusted into an 8 bit format for increasing processing speed. The adjusted algorithm was introduce into a microcontroller and used to determine the effort made in a muscle through the acquisition and processing of a microelectric signal.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114617316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"IEEE 802.16e Design Issues and Transceiver Architecture Selection for Mobile WiMAX Systems","authors":"L. A. Sánchez-Gaspariano, A. Díaz-Sánchez","doi":"10.1109/CONIELECOMP.2008.28","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.28","url":null,"abstract":"Analysis of diverse transceiver architectures available for wireless communication systems are addressed in this work. The aim is to determine which of those is better suited for mobile Worldwide Interoperability for Microwave Access (WiMAX) systems. In order to accomplish such task, a general description of the IEEE 802.16e standard is presented focusing on its most important characteristics and pointing out the most stringent requirements it imposes for data transmission and reception.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125700000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Corona‐Chavez, I. Llamas-Garro, Jung-Mu Kim, Yong-Kweon Kim
{"title":"A Novel Wide-Band Butler Matrix for Vehicle Radars at 24GHz","authors":"A. Corona‐Chavez, I. Llamas-Garro, Jung-Mu Kim, Yong-Kweon Kim","doi":"10.1109/CONIELECOMP.2008.37","DOIUrl":"https://doi.org/10.1109/CONIELECOMP.2008.37","url":null,"abstract":"There is a great scientific and commercial interest in car radars for anti-crash and pre-crash systems, for which beamformer networks with antenna arrays are becoming the norm. In this paper a novel Butler matrix at 24 GHz using a new type of micromachined suspended transmission-line couplers presented. This configuration arranges all the couplers in the center so that no line crossovers are needed. This circuit has been micromachined on a glass-quartz substrate and BCB layers have been used to suspend the transmission lines of the coupler. In this paper the fabrication method will be fully described, simulated and preliminary experimental results are presented.","PeriodicalId":202730,"journal":{"name":"18th International Conference on Electronics, Communications and Computers (conielecomp 2008)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124143066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}