Pub Date : 2004-11-07DOI: 10.1109/ACSSC.2004.1399200
B. Bonney, R. Ives, D. Etter, Yingzi Du
Iris recognition has been shown to be very accurate for human identification. In this paper, we develop a technique for iris pattern extraction utilizing the least significant bit-plane: the least significant bit of every pixel in the image. Through binary morphology applied to the bit-plane, the pupillary boundary of the iris is determined. The limbic boundary is identified by evaluating the standard deviation of the image intensity along the vertical and horizontal axes. Because our extraction approach restricts localization techniques to evaluating only bit-planes and standard deviations, iris pattern extraction is not dependent on circular edge detection. This allows for an expanded functionality of iris identification technology by no longer requiring a frontal view, which leads to the potential for off-angle iris recognition technology. Initial results show that it is possible to fit a close elliptical approximation to an iris pattern by using only bit-planes and standard deviations for iris localization.
{"title":"Iris pattern extraction using bit planes and standard deviations","authors":"B. Bonney, R. Ives, D. Etter, Yingzi Du","doi":"10.1109/ACSSC.2004.1399200","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399200","url":null,"abstract":"Iris recognition has been shown to be very accurate for human identification. In this paper, we develop a technique for iris pattern extraction utilizing the least significant bit-plane: the least significant bit of every pixel in the image. Through binary morphology applied to the bit-plane, the pupillary boundary of the iris is determined. The limbic boundary is identified by evaluating the standard deviation of the image intensity along the vertical and horizontal axes. Because our extraction approach restricts localization techniques to evaluating only bit-planes and standard deviations, iris pattern extraction is not dependent on circular edge detection. This allows for an expanded functionality of iris identification technology by no longer requiring a frontal view, which leads to the potential for off-angle iris recognition technology. Initial results show that it is possible to fit a close elliptical approximation to an iris pattern by using only bit-planes and standard deviations for iris localization.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114936120","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399175
S. Demirsoy, I. Kale, A. Dempster
Reconfigurable multiplier blocks (ReMB) offer significant complexity reductions in multiple constant multiplications in time-multiplexed digital filters. In this paper the ReMB technique is employed in the implementation of a half-band 32-tap FIR filter on both Xilinx Virtex FPGA and UMC 0.18 /spl mu/m CMOS technologies. Reference designs have also been built by deploying standard time-multiplexed architectures and off-the-shelf Xilinx core generator system for the FPGA design. All designs are then compared for their area and delay figures. It is shown that, the ReMB technique can significantly reduce the area for the multiplier circuitry and the coefficient store, as well as reducing the delay.
{"title":"Efficient implementation of digital filters using novel reconfigurable multiplier blocks","authors":"S. Demirsoy, I. Kale, A. Dempster","doi":"10.1109/ACSSC.2004.1399175","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399175","url":null,"abstract":"Reconfigurable multiplier blocks (ReMB) offer significant complexity reductions in multiple constant multiplications in time-multiplexed digital filters. In this paper the ReMB technique is employed in the implementation of a half-band 32-tap FIR filter on both Xilinx Virtex FPGA and UMC 0.18 /spl mu/m CMOS technologies. Reference designs have also been built by deploying standard time-multiplexed architectures and off-the-shelf Xilinx core generator system for the FPGA design. All designs are then compared for their area and delay figures. It is shown that, the ReMB technique can significantly reduce the area for the multiplier circuitry and the coefficient store, as well as reducing the delay.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115003146","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399504
B. A. Obeidat, Yimin D. Zhang, M. Amin
This paper presents an approach for direction-of-arrival (DOA) and polarization estimations of far-field wideband signals using an array of cross-polarized dual-feed sensors. The wideband signals are decomposed into a set of narrowband signals. The coherent signal subspace processing technique is then applied to dimensionally extended source signal correlation matrices to construct a signal subspace. The utilization of polarization diversity through the use of a dual-feed cross-polarized array to process the polarized source signals lends an additional degree of freedom, leading to performance improvement over the case where only a single-polarization array is used.
{"title":"DOA and polarization estimation for wideband sources","authors":"B. A. Obeidat, Yimin D. Zhang, M. Amin","doi":"10.1109/ACSSC.2004.1399504","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399504","url":null,"abstract":"This paper presents an approach for direction-of-arrival (DOA) and polarization estimations of far-field wideband signals using an array of cross-polarized dual-feed sensors. The wideband signals are decomposed into a set of narrowband signals. The coherent signal subspace processing technique is then applied to dimensionally extended source signal correlation matrices to construct a signal subspace. The utilization of polarization diversity through the use of a dual-feed cross-polarized array to process the polarized source signals lends an additional degree of freedom, leading to performance improvement over the case where only a single-polarization array is used.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115041290","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399531
B. G. Quinn
We consider in this paper a class of techniques for the estimation of the direction of arrival of a narrowband signal. Eigenvectors of a spectral covariance matrix corresponding to a number of the lowest eigenvalues are used to estimate the bearing. It is shown that the estimator has a non-standard asymptotic distribution.
{"title":"Subspace estimators of direction of arrival","authors":"B. G. Quinn","doi":"10.1109/ACSSC.2004.1399531","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399531","url":null,"abstract":"We consider in this paper a class of techniques for the estimation of the direction of arrival of a narrowband signal. Eigenvectors of a spectral covariance matrix corresponding to a number of the lowest eigenvalues are used to estimate the bearing. It is shown that the estimator has a non-standard asymptotic distribution.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115081146","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399564
W. Souidène, Azeddine Beghdadi, K. Abed-Meraim, B. Mouhouche
In this paper we deal with blind image restoration in a multi-channel framework. We use the mutually referenced equalizers (MRE) in order to perform exact image restoration in the noiseless case and under some identifiability conditions. In presence of noise, this method fails to restore correctly the original image. So, we introduce a regularization term to improve the restored image quality. We introduce two regularization techniques: a norm minimization scheme and an eigen value truncation scheme in order to perform the regularization and reduce the noise amplification assigned to image restoration. We compare the performance gain of our method for different number of observed images with the mono-channel case. We evaluate the performance of our method using an image similarity index.
{"title":"Regularized MRE method for blind multichannel image deconvolution","authors":"W. Souidène, Azeddine Beghdadi, K. Abed-Meraim, B. Mouhouche","doi":"10.1109/ACSSC.2004.1399564","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399564","url":null,"abstract":"In this paper we deal with blind image restoration in a multi-channel framework. We use the mutually referenced equalizers (MRE) in order to perform exact image restoration in the noiseless case and under some identifiability conditions. In presence of noise, this method fails to restore correctly the original image. So, we introduce a regularization term to improve the restored image quality. We introduce two regularization techniques: a norm minimization scheme and an eigen value truncation scheme in order to perform the regularization and reduce the noise amplification assigned to image restoration. We compare the performance gain of our method for different number of observed images with the mono-channel case. We evaluate the performance of our method using an image similarity index.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115107762","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399519
S. Cheng, M. Valenti
This paper studies bit interleaved coded modulation (BICM) using noncoherent orthogonal modulation (e.g. NFSK). To improve performance, information is fed from the decoder back to the demodulator, using the recently proposed strategy known as BICM with iterative demodulation (BICM-ID). The capacity of noncoherent orthogonal modulation under BICM constraints is compared against that with joint demodulation and decoding (which BICM-ID approximates). Also, the convergence behavior of iterative demodulation with turbo decoding is investigated by using density evolution.
{"title":"Bit-interleaved turbo-coded noncoherent orthogonal modulation with iterative demodulation and decoding: capacity limits and convergence analysis","authors":"S. Cheng, M. Valenti","doi":"10.1109/ACSSC.2004.1399519","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399519","url":null,"abstract":"This paper studies bit interleaved coded modulation (BICM) using noncoherent orthogonal modulation (e.g. NFSK). To improve performance, information is fed from the decoder back to the demodulator, using the recently proposed strategy known as BICM with iterative demodulation (BICM-ID). The capacity of noncoherent orthogonal modulation under BICM constraints is compared against that with joint demodulation and decoding (which BICM-ID approximates). Also, the convergence behavior of iterative demodulation with turbo decoding is investigated by using density evolution.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117247355","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399401
Haiping Wu, B. Hamzeh, Mohsen Kavehrad
Due to the difficulty of deploying fiber-to-home, the solution for the last-mile problem remains an unsolved challenge. Among all the alternatives, free-space optics (FSO) shows great potential due to its non-interfering nature and abundant available bandwidth. However, because the operational status of an FSO link is highly weather dependent, feasibility of using FSO to deliver data to end-users remains questionable. A hybrid architecture that utilizes the complementary nature of FSO and radio frequency (RF) links with respect to their individual weather sensitivities has been proposed to significantly increase availability. According to this architecture, we developed a channel model integrating the RF and FSO channels. Experimental measurements are also taken into account in order to verify validity of the model. Based on the model and available weather condition data, we concluded that the hybrid link does demonstrate significantly better availability than the FSO alone case. Carrier class availability can be achieved.
{"title":"Achieving carrier class availability of FSO link via a complementary RF link","authors":"Haiping Wu, B. Hamzeh, Mohsen Kavehrad","doi":"10.1109/ACSSC.2004.1399401","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399401","url":null,"abstract":"Due to the difficulty of deploying fiber-to-home, the solution for the last-mile problem remains an unsolved challenge. Among all the alternatives, free-space optics (FSO) shows great potential due to its non-interfering nature and abundant available bandwidth. However, because the operational status of an FSO link is highly weather dependent, feasibility of using FSO to deliver data to end-users remains questionable. A hybrid architecture that utilizes the complementary nature of FSO and radio frequency (RF) links with respect to their individual weather sensitivities has been proposed to significantly increase availability. According to this architecture, we developed a channel model integrating the RF and FSO channels. Experimental measurements are also taken into account in order to verify validity of the model. Based on the model and available weather condition data, we concluded that the hybrid link does demonstrate significantly better availability than the FSO alone case. Carrier class availability can be achieved.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117254472","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399319
J. S. Crockett, T. Moon, J. Gunther, O. Chauhan
The eigenmessage decoder O. Chauhan et al. (2003) expresses a degree of nonlocality in a message passing decoder by representing an entire cycle in a single linear equation. The eigenvector for the linear message passing matrix represents a fixed point of the message passing algorithm around a cycle and has been shown to significantly decrease the number of iterations required for low-density parity-check (LDPC) decoding using message passing. In this paper, we extend the eigenmessage idea to simultaneously solving for a fixed point of multiple cycles. The representation is thus nonlocal over a broader section of the graph. This multiple-cycle eigenmessage algorithm shows improvement over traditional belief propagation (BP) methods. We present and compare results for the new algorithm and consider possible variations.
{"title":"Accelerating LDPC decoding using multiple-cycle eigenmessages","authors":"J. S. Crockett, T. Moon, J. Gunther, O. Chauhan","doi":"10.1109/ACSSC.2004.1399319","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399319","url":null,"abstract":"The eigenmessage decoder O. Chauhan et al. (2003) expresses a degree of nonlocality in a message passing decoder by representing an entire cycle in a single linear equation. The eigenvector for the linear message passing matrix represents a fixed point of the message passing algorithm around a cycle and has been shown to significantly decrease the number of iterations required for low-density parity-check (LDPC) decoding using message passing. In this paper, we extend the eigenmessage idea to simultaneously solving for a fixed point of multiple cycles. The representation is thus nonlocal over a broader section of the graph. This multiple-cycle eigenmessage algorithm shows improvement over traditional belief propagation (BP) methods. We present and compare results for the new algorithm and consider possible variations.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116169443","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399582
C. Demiroğlu, S. Kamath, D.V. Anderson, M. Clements, T. Barnwell
Despite the significant progress, low perceptual quality of encoded noisy speech is still an unsolved problem. The quality problem at noisy environments is addressed for MELP speech encoder by using a novel speech enhancement algorithm at the front-end. The speech signal is segmented into broad phonetic classes using auxiliary sensors in addition to the acoustic microphone. Each phoneme class is enhanced by suppressing maximum noise while minimally distorting perceptually important cues using the acoustic-phonetic knowledge about the class. The A/B quality test shows significant improvement over the MELPe coder that uses MMSE algorithm for enhancement.
{"title":"Segmentation-based noise suppression for speech coders using auxiliary sensors","authors":"C. Demiroğlu, S. Kamath, D.V. Anderson, M. Clements, T. Barnwell","doi":"10.1109/ACSSC.2004.1399582","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399582","url":null,"abstract":"Despite the significant progress, low perceptual quality of encoded noisy speech is still an unsolved problem. The quality problem at noisy environments is addressed for MELP speech encoder by using a novel speech enhancement algorithm at the front-end. The speech signal is segmented into broad phonetic classes using auxiliary sensors in addition to the acoustic microphone. Each phoneme class is enhanced by suppressing maximum noise while minimally distorting perceptually important cues using the acoustic-phonetic knowledge about the class. The A/B quality test shows significant improvement over the MELPe coder that uses MMSE algorithm for enhancement.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123910831","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 : 2004-11-07DOI: 10.1109/ACSSC.2004.1399506
R. Vaccaro, N. Owsley
This paper considers the problem of estimating directions of arrival (DOAs) from sensor-array data when the positions of the sensors are not precisely known. The proposed algorithm is an extension of a previously developed approach based on weighted subspace fitting. The new algorithm shows improved robustness with respect to sensor position perturbations, particularly when estimating the DOAs of weak sources. The robust algorithm treats the sensor position perturbations as unknown deterministic parameters and estimates them jointly with the DOAs.
{"title":"Robust direction finding","authors":"R. Vaccaro, N. Owsley","doi":"10.1109/ACSSC.2004.1399506","DOIUrl":"https://doi.org/10.1109/ACSSC.2004.1399506","url":null,"abstract":"This paper considers the problem of estimating directions of arrival (DOAs) from sensor-array data when the positions of the sensors are not precisely known. The proposed algorithm is an extension of a previously developed approach based on weighted subspace fitting. The new algorithm shows improved robustness with respect to sensor position perturbations, particularly when estimating the DOAs of weak sources. The robust algorithm treats the sensor position perturbations as unknown deterministic parameters and estimates them jointly with the DOAs.","PeriodicalId":396779,"journal":{"name":"Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004.","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126170002","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：