Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4392094
P. Sanguansat, W. Asdornwised, S. Marukatat, S. Jitapunkul
In this paper, we proposed a novel technique for face recognition using Two-Dimensional Random Subspace Analysis (2DRSA), based on the Two-Dimensional Principal Component Analysis (2DPCA) technique and Random Subspace Method (RSM). In conventional 2DPCA, the image covariance matrix is directly calculated via 2D images in matrix form, by concept of the covariance of a random variable. However, 2DPCA reduces the dimension of the original image matrix in only one directions, normally in the row direction. Thus, it needs many more coefficients for image representation than PCA. For solving this problem, many methods were proposed by considering both the row and column directions. We develop another technique to reduce the dimension of 2DPCA feature matrix in column direction by using of randomization in selecting the rows of feature matrix. And the ensemble classification method is used to classify these feature subspaces. Experimental results on Yale, ORL and AR face databases show the improvement of our proposed techniques over the conventional 2DPCA.
{"title":"Two-Dimensional Random Subspace Analysis for face recognition","authors":"P. Sanguansat, W. Asdornwised, S. Marukatat, S. Jitapunkul","doi":"10.1109/ISCIT.2007.4392094","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392094","url":null,"abstract":"In this paper, we proposed a novel technique for face recognition using Two-Dimensional Random Subspace Analysis (2DRSA), based on the Two-Dimensional Principal Component Analysis (2DPCA) technique and Random Subspace Method (RSM). In conventional 2DPCA, the image covariance matrix is directly calculated via 2D images in matrix form, by concept of the covariance of a random variable. However, 2DPCA reduces the dimension of the original image matrix in only one directions, normally in the row direction. Thus, it needs many more coefficients for image representation than PCA. For solving this problem, many methods were proposed by considering both the row and column directions. We develop another technique to reduce the dimension of 2DPCA feature matrix in column direction by using of randomization in selecting the rows of feature matrix. And the ensemble classification method is used to classify these feature subspaces. Experimental results on Yale, ORL and AR face databases show the improvement of our proposed techniques over the conventional 2DPCA.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133781752","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4391975
Eduardo I. Silva, Daniel E. Quevedo, Graham C. Goodwin
When employing multibit data converters the necessity arises to compensate for digital to analog converter (DAC) element mismatch. The most widespread compensation techniques are based on digital element matching (DEM) and, if properly designed, these can achieve almost arbitrary DAC mismatch noise shaping. This paper gives a closed form expression for the optimal DEM noise shaping profile. It depends upon the spectrum of the analog signal to be quantized and may also include a frequency weighting filter which reflects perceptual criteria.
{"title":"Optimal multibit Digital to Analog Conversion","authors":"Eduardo I. Silva, Daniel E. Quevedo, Graham C. Goodwin","doi":"10.1109/ISCIT.2007.4391975","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391975","url":null,"abstract":"When employing multibit data converters the necessity arises to compensate for digital to analog converter (DAC) element mismatch. The most widespread compensation techniques are based on digital element matching (DEM) and, if properly designed, these can achieve almost arbitrary DAC mismatch noise shaping. This paper gives a closed form expression for the optimal DEM noise shaping profile. It depends upon the spectrum of the analog signal to be quantized and may also include a frequency weighting filter which reflects perceptual criteria.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122476861","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4391995
Seokjin Kim, M. Peckerar
High-speed analog-to-digital converter using on-chip digital de-multiplexing and clock distribution is presented with detail sequences of operation for dynamic performance testing. Digital outputs are post processed and fed into a computer-aided ADC performance characterization tool. The problems of high sampling rate ADC testing are described. The test methodologies described reduce test costs and overcome many test hardware limitations. As our focus is on satellite receiver systems, we emphasize the measurement of inter-modulation distortion and effective resolution bandwidth. As a primary characterization component, Fourier analysis is used and we address the issue of sample window adjustment to eliminate spectral leakage and false spur generation. A 6-bit 800 MSa/s dual channel SiGe-based ADC from Hughes network systems is used as a target example.
{"title":"High speed analog-to-digital converter design verification tests in satellite receivers","authors":"Seokjin Kim, M. Peckerar","doi":"10.1109/ISCIT.2007.4391995","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391995","url":null,"abstract":"High-speed analog-to-digital converter using on-chip digital de-multiplexing and clock distribution is presented with detail sequences of operation for dynamic performance testing. Digital outputs are post processed and fed into a computer-aided ADC performance characterization tool. The problems of high sampling rate ADC testing are described. The test methodologies described reduce test costs and overcome many test hardware limitations. As our focus is on satellite receiver systems, we emphasize the measurement of inter-modulation distortion and effective resolution bandwidth. As a primary characterization component, Fourier analysis is used and we address the issue of sample window adjustment to eliminate spectral leakage and false spur generation. A 6-bit 800 MSa/s dual channel SiGe-based ADC from Hughes network systems is used as a target example.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122750587","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4391996
Jian Zhu, Jinchun Gao, G. Xie, Yuan'an Liu
Based on finite element method (FEM), the impact of coaxial connection failure on high speed signal transmission was researched. The contact resistance, contact inductance and interfacial capacitance were calculated at high frequencies. According to the improved model of contact impedance, the influence on high speed signal transmission was analyzed. Experiment was taken to measure the DC contact resistance and high frequency impedance of some degraded BNC coaxial connectors. The impact of connection failure on E2 data transmission was also observed in the experiment. Some important conclusion was summarized to explain the malfunction in communication system due to the contact failure.
{"title":"FEM analysis of the impact of coaxial connector on high speed signal transmission","authors":"Jian Zhu, Jinchun Gao, G. Xie, Yuan'an Liu","doi":"10.1109/ISCIT.2007.4391996","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391996","url":null,"abstract":"Based on finite element method (FEM), the impact of coaxial connection failure on high speed signal transmission was researched. The contact resistance, contact inductance and interfacial capacitance were calculated at high frequencies. According to the improved model of contact impedance, the influence on high speed signal transmission was analyzed. Experiment was taken to measure the DC contact resistance and high frequency impedance of some degraded BNC coaxial connectors. The impact of connection failure on E2 data transmission was also observed in the experiment. Some important conclusion was summarized to explain the malfunction in communication system due to the contact failure.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117133031","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4392068
M. Saravanan, S. Ravi
Software radio development aims at wideband RF access and software partitioning for plug-and-play type of use. The development is facilitated by progress in silicon capabilities, silicon capabilities, signal processing power of new and future processors and reconfiguration methods (software download, smartcards, etc.). The future wireless and multimedia systems differ from old systems and from each other in terms of access methods, modulation, coding, etc. and they will also provide new type of services. This results in need for many product platforms unless we aren't able to design a common platform that could be programmed to different standards. The software radio is a good solution to this problem since it is reconfigurable to suit different standards at different continents. For this IS-95 CDMA technique is modified as a method of spread spectrum multiple access technique called frequency hopping/multiple carrier direct sequence-code division multiple access by Yang and Hanzo (2002) (FH/MC DS-CDMA). In this work, software defined radio (SDR) based FH/MC DS-CDMA transreceiver is proposed for future generation as well as existing generation Networks, which can carry multimedia applications at higher speed. Multiple carriers can be allotted as per user requirements with high secrecy and multiple encryptions. The performance analysis for the above scheme is shown supportive in terms of BER, power requirements, complexity, etc.
{"title":"SDR based multiple access technique for multimedia applications","authors":"M. Saravanan, S. Ravi","doi":"10.1109/ISCIT.2007.4392068","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392068","url":null,"abstract":"Software radio development aims at wideband RF access and software partitioning for plug-and-play type of use. The development is facilitated by progress in silicon capabilities, silicon capabilities, signal processing power of new and future processors and reconfiguration methods (software download, smartcards, etc.). The future wireless and multimedia systems differ from old systems and from each other in terms of access methods, modulation, coding, etc. and they will also provide new type of services. This results in need for many product platforms unless we aren't able to design a common platform that could be programmed to different standards. The software radio is a good solution to this problem since it is reconfigurable to suit different standards at different continents. For this IS-95 CDMA technique is modified as a method of spread spectrum multiple access technique called frequency hopping/multiple carrier direct sequence-code division multiple access by Yang and Hanzo (2002) (FH/MC DS-CDMA). In this work, software defined radio (SDR) based FH/MC DS-CDMA transreceiver is proposed for future generation as well as existing generation Networks, which can carry multimedia applications at higher speed. Multiple carriers can be allotted as per user requirements with high secrecy and multiple encryptions. The performance analysis for the above scheme is shown supportive in terms of BER, power requirements, complexity, etc.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"23 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114163694","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4392119
S. Majid, K. Ahmed
Disasters in last decade have rapidly increased the research activities related to emergency communications. This paper presents a model for cognitive identification of post-disaster situation. A two-state model for mobile handsets along with a software based identification module is introduced for the said purpose. This paper also discusses implementation solutions based on: traditional cellular network features, cognitive radio using game theory and artificial neural networks. At the end of paper we present analysis considering the time taken for the identification of emergency situation and probability of false alarming of such situations.
{"title":"CIP - cognitive identification of post-disaster communications","authors":"S. Majid, K. Ahmed","doi":"10.1109/ISCIT.2007.4392119","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392119","url":null,"abstract":"Disasters in last decade have rapidly increased the research activities related to emergency communications. This paper presents a model for cognitive identification of post-disaster situation. A two-state model for mobile handsets along with a software based identification module is introduced for the said purpose. This paper also discusses implementation solutions based on: traditional cellular network features, cognitive radio using game theory and artificial neural networks. At the end of paper we present analysis considering the time taken for the identification of emergency situation and probability of false alarming of such situations.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"9 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116863019","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4392055
Lan Wang, Daqing Gu
The IMS-based, half-duplex push-to-talk over cellular (PoC) service provides a cost-efficient, interactive, and global-reach service for group and individual communications. The media types for PoC users can be voice, video, images, and text messages. Presence service is widely used and is often bundled with PoC and instant messaging (IM) to indicate other users' availability and willingness of communications. In this paper, we investigate the session setup procedure for the PoC group communications within OMA PoC infrastructure and propose a method to optimize the initiation of a PoC prearranged group session using rich presence information. With this method, the SIP signaling traffic and session delay are significantly reduced.
{"title":"A study on session setup for group communications in push-to-talk over cellular using rich presence","authors":"Lan Wang, Daqing Gu","doi":"10.1109/ISCIT.2007.4392055","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392055","url":null,"abstract":"The IMS-based, half-duplex push-to-talk over cellular (PoC) service provides a cost-efficient, interactive, and global-reach service for group and individual communications. The media types for PoC users can be voice, video, images, and text messages. Presence service is widely used and is often bundled with PoC and instant messaging (IM) to indicate other users' availability and willingness of communications. In this paper, we investigate the session setup procedure for the PoC group communications within OMA PoC infrastructure and propose a method to optimize the initiation of a PoC prearranged group session using rich presence information. With this method, the SIP signaling traffic and session delay are significantly reduced.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115165386","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4391985
M.A.G. Lorenzo, A. Manzano, M. Gusad, J. Hizon, M. Rosales
The paper presents the design and implementation of six operational amplifiers with rail-to-rail input and output capability. The study characterizes several rail-to-rail input and output stages and the dependence of the op-amp's operation on different design parameters to formulate a standard design methodology that can serve as a guide for future researches and projects in the area of rail-to-rail amplifiers. The report shows the effects of the rail-to-rail stages on the op-amp's input common-mode range and output voltage swing range. The op-amps are implemented in 0.25 mum CMOS process and the simulation results achieve specifications such as gain, bandwidth, offset voltages and common-mode rejection ratio comparable with commercially available circuits.
本文介绍了六种具有轨对轨输入输出能力的运算放大器的设计与实现。该研究描述了几个轨对轨输入和输出阶段，以及运算放大器的运行对不同设计参数的依赖关系，以制定一个标准的设计方法，可以作为轨对轨放大器领域未来研究和项目的指导。该报告显示了轨对轨级对运放输入共模范围和输出电压摆幅范围的影响。运算放大器采用0.25 μ m CMOS工艺实现，仿真结果达到了与市售电路相当的增益、带宽、失调电压和共模抑制比等规格。
{"title":"Design and implementation of CMOS rail-to-rail operational amplifiers","authors":"M.A.G. Lorenzo, A. Manzano, M. Gusad, J. Hizon, M. Rosales","doi":"10.1109/ISCIT.2007.4391985","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4391985","url":null,"abstract":"The paper presents the design and implementation of six operational amplifiers with rail-to-rail input and output capability. The study characterizes several rail-to-rail input and output stages and the dependence of the op-amp's operation on different design parameters to formulate a standard design methodology that can serve as a guide for future researches and projects in the area of rail-to-rail amplifiers. The report shows the effects of the rail-to-rail stages on the op-amp's input common-mode range and output voltage swing range. The op-amps are implemented in 0.25 mum CMOS process and the simulation results achieve specifications such as gain, bandwidth, offset voltages and common-mode rejection ratio comparable with commercially available circuits.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116158554","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4392195
U. Gunawardana, K. Nguyen, R. Liyana-Pathirana
In this paper, we illustrate the use of importance sampling (IS) for efficient simulation of Turbo Codes over additive white Gaussian noise (AWGN) channels. In particular, we show how to bias the probability density function (pdf) of the AWGN process using the most probable error path (MPEP) method in order to maximize the computational efficiency gain. The new noise pdf is designed based on the optimal biased distribution where zero variance estimator can be achieved. It is demonstrated that the proposed method requires much smaller sample sizes to achieve the same accuracy required by a conventional MC estimator.
{"title":"Fast simulation of turbo codes over AWGN channels","authors":"U. Gunawardana, K. Nguyen, R. Liyana-Pathirana","doi":"10.1109/ISCIT.2007.4392195","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392195","url":null,"abstract":"In this paper, we illustrate the use of importance sampling (IS) for efficient simulation of Turbo Codes over additive white Gaussian noise (AWGN) channels. In particular, we show how to bias the probability density function (pdf) of the AWGN process using the most probable error path (MPEP) method in order to maximize the computational efficiency gain. The new noise pdf is designed based on the optimal biased distribution where zero variance estimator can be achieved. It is demonstrated that the proposed method requires much smaller sample sizes to achieve the same accuracy required by a conventional MC estimator.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115654243","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}
Pub Date : 2007-12-04DOI: 10.1109/ISCIT.2007.4392079
Tan Li, R. Zhang, R. Yang, Heyun Huang, Fuhuei Lin
MDCT/IMDCT has been widely adopted to transform an audio sequence from time domain to transform domain by various audio codec standards. This paper presents a unified algorithm and its hardware design for cosine modulated filter bank. In algorithm derivation, both MDCT and IMDCT are first converted to a half size DCT-IV with input or output permutation. The DCT-IV is then realized by a fast DCT-II algorithm. Both radix-3 and radix-2 DCT-II algorithms are analyzed and a unified computing kernel is concluded.
{"title":"A unified computing kernel for MDCT/IMDCT in modern audio coding standards","authors":"Tan Li, R. Zhang, R. Yang, Heyun Huang, Fuhuei Lin","doi":"10.1109/ISCIT.2007.4392079","DOIUrl":"https://doi.org/10.1109/ISCIT.2007.4392079","url":null,"abstract":"MDCT/IMDCT has been widely adopted to transform an audio sequence from time domain to transform domain by various audio codec standards. This paper presents a unified algorithm and its hardware design for cosine modulated filter bank. In algorithm derivation, both MDCT and IMDCT are first converted to a half size DCT-IV with input or output permutation. The DCT-IV is then realized by a fast DCT-II algorithm. Both radix-3 and radix-2 DCT-II algorithms are analyzed and a unified computing kernel is concluded.","PeriodicalId":331439,"journal":{"name":"2007 International Symposium on Communications and Information Technologies","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123361502","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}
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