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IEEE International Conference on Image processing

作者： X.K. Yang C. Zhu Z.G. Li G.N. Feng S. Wu N. Ling Signal Processing Program Laboratories for Information Technology Singapore Department of Computer Engineering Santa Clara University Santa Clara CA USA

This paper presents an unequal error protection scheme for motion compensated video over the Internet. The forward error correction (FEC) codes are optimally assigned to different frames in group of picture (GOP) by exploiting the temporal dependency among frames. To achieve optimal allocation of FEC assigned in GOP, we propose a performance criterion for the measurement of allocation, namely the expected length of error propagation (ELEP), which makes sense intuitively, as fewer frames corrupted implies better quality of reconstruction. Experiment results show the proposed scheme is robust to burst packet loss in the Internet. More importantly, graceful degradation of video quality is achieved by the proposed scheme as the packet loss probability of an Internet connection increases.

关键词： Error correction codes Streaming media Internet Forward error correction Computer errors Robustness Degradation Propagation losses Video compression Encoding

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Kalman-filter based chip estimator for WCDMA downlink detection 10

Kalman-filter based chip estimator for WCDMA downlink detect...

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2000 10th European signal processing Conference, EUSIPCO 2000

作者： Werner, S. De Campos, M.L.R. Apolinário, J.A. Helsinki University of Technolog Signal Processing Laboratory P.O. Box 3000 HelsinkiFIN-02015 Finland COPPE Federal Univ. of Rio de Janeiro Electrical Engineering Program P.O. Box 68504 Rio de Janeiro RJ21.945-970 Brazil Escuela Politécnica Del Ejército Facultad de Ingenieria Electrónica P. O. Box 231-B Quito Ecuador

ISBN: (纸本)9789521504433

In the WCDMA downlink, the multipath channel destroys orthogonality between users and causes multiple access interference (MAI). This channel-induced MAI can be combated by channel equalization to approximately restore orthogonality. This paper presents a chip-estimator method based on Kalman filtering suitable for WCDMA downlink. The method does not require a training sequence or the knowledge of other-users' spreading codes. Simulation results show considerable performance improvement using the proposed estimator compared with that of the RAKE receiver. © 2000 EUSIPCO.

关键词： Multiple access interference

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Approximation of group delay response of allpass filters using weighted least square method

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1996年第6期79卷 60-69页

作者： Okuda, M Matsuyama, K Ikehara, M Faculty of Science and Technology Keio University Yokohama Japan 223 Mashiro Okuda received his B.E. and M.E. degrees in Electrical Engineering from Keio University in 1993 and 1995 respectively where he is currently in the doctoral program. He is engaged in research on digital signal processing.

Allpass filters with prescribed group-delay response are useful in compensating such response. In general, the approximation of group-delay response is formulated as a nonlinear problem;thus, its approximation becomes difficult. The design methods with nonlinear optimization have the problem that initial values of filter coefficients are needed and heavy computation is required. The design method is simplified in the conventional method where magnitude response is approximated instead of group-delay response, but the approximation error is increased in the indirect methods. This paper proposes a method in which group-delay response is approximated by a linear function and optimal solution is obtained in the least square sense by iteratively solving the linear equations. This method has the merit that the error of group-delay response is directly evaluated. Moreover, applying Lawson's algorithm to this method, an equiripple solution can be obtained and maximum value of error can be decreased.

关键词： group-delay response allpass filter weighted least square method equiripple approximation

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EDGE-PRESERVING SMOOTHING USING THE FUZZY CONTROL TECHNIQUE

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1995年第1期78卷 32-43页

作者： TAKASHIMA, H TAGUCHI, A MURATA, Y Associate Member Faculty of Engineering Musashi Institute of Technology Tokyo Japan 158 Hironori Takashirna received his B.E. degree in 1993 from the Department of Elect. Elect. Eng. Musashi Institute of Technology where he is presently in the Master's program. He is engaged in research on nonlinear digital signal processing. Member Nonmember

When a random noise is superposed on a signal with an abrupt change (i.e., edge), as in the case of the image signal, there is a large overlap of the frequency component between the abrupt changes (edge) of the signal and the noise. Then it is impossible to realize both the noise elimination and the edge preservation sufficiently by the conventional linear filter, such as the mean filter. Thus, a nonlinear technique is required in order to eliminate the noise and preserve details of the original signal where the coefficient of the smoothing filter is determined according to the properties of the data in the window. There can be more than one observed value in the filter window that can be used to specify the properties of the data. It is difficult, however, to represent precisely the properties of the image signal using a single observed value. In addition, the observed values contain ambiguities since they are calculated from the local image data with superposed noise. In other words, it is required to determine the filter coefficients based on multiple observed values containing ambiguities. For such a problem, the fuzzy control rule, which is utilized effectively in control problems, can be applied to calculate the control variable (i.e., filter coefficient) adequately by the nonlinear technique from the multiple observed values containing ambiguities. In this paper, the nonlinear filtering technique based on the fuzzy control rule is presented and the usefulness of the filter in the noise elimination from the image signal is demonstrated.

关键词： NONLINEAR FILTER FUZZY CONTROL RULE

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Improvement of convergence speed for subband adaptive digital filter using the multirate repeating method

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1995年第10期78卷 37-45页

作者： Kiya, H Nishikawa, K Ashihara, K Faculty of Technology Tokyo Metropolitan University Hachioji Japan 192-03 Members Kiyoshi Nshikawa graduated in 1990 from the Department of Electrical Engineering Tokyo Metropolitan University where he completed the Master's Program in 1992 and affiliated with Nippon Steel Co. Computer Systems Laboratory. He was a Research Associate in 1993 in the Department of Elect. Inf. Eng. Tokyo Metropolitan University engaged in research onadaptive signal processing and information source coding. He is a member of the IEEE. Associate Member

The subband adaptive system, where the idea of the filter bank is applied to the adaptive filter, has a feature that a higher-order adaptation can be reduced to lower-order adaptations. The reduction of the order of the adaptive filter is related closely to the number of channels and the decimation ratio. The order of adaptive digital filter (ADF) is decreased greatly when the number of subbands is increased, and the decimation ratio is increased up to the maximum value. Then, however, the number of coefficient-updates per unit time is decreased, which results in the deterioration of the convergence Speed. From such a viewpoint, this paper discusses a method to improve the convergence speed, which is deteriorated in the subband adaptive system, due to the decimation. The idea of the proposed method is to utilize effectively the data which have been discarded in the decimation process and to improve the convergence speed. It is called the multirate repeating method. As the first step, the multirate repeating method is applied to the conventional subband adaptive system and the convergence speed is improved. Then a subband adaptive system is introduced in which the multirate repeating method can be utilized more effectively. As a result, a faster convergence is realized while retaining the ADF order-reduction effect, which is an advantage of the subband adaptive system.

关键词： adaptive signal processing subband adaptive system multirate repeating method rational decimation

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DECIMATION RATIO IN SUBBAND ADAPTIVE IDENTIFICATION OF A TIME-VARYING AR MODEL

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1994年第11期77卷 78-90页

作者： SHIMIZU, J MIYANAGA, Y TOCHINAI, K Department of Electronic Engineering Faculty of Engineering Hokkaido University Sapporo Japan 060 Jun'ya Shimizu received his B.S. and M.S. degrees from Hokkaido University Sapporo Japan in 1992 and 1994 respectively. Since 1994 he has been in the doctoral program in the Department of Electronic Engineering Hokkaido University. His research interests include adaptive digital signal processing and multirate signal processing. He is a member of the I.E.E.E. (USA).

This paper presents some conditions to determine decimation ratio in subband adaptive identification of a time-varying system. It has been reported in some experiments that a large decimation ratio is not suitable for subband identification of a time-varying system. However, theoretical conditions for a maximally decimated ratio in a time-varying system have not to date been reported. A short-time invariant model is the starting point for this research. The relation between a forgetting factor used in the recursive weighted least-squares (RWLS) algorithm and a time variation of the time-varying system are derived. Then, new forgetting factors are derived for the multirate processing case. Using a convergence property provided by these forgetting factors, theoretical conditions are obtained having parameters estimated from decimated signals that are as accurate as those from all observed signals. The propriety of these conditions is demonstrated using simulations.

关键词： ADAPTIVE SYSTEM IDENTIFICATION IN SUBBANDS DECIMATION RATIO TIME-VARYING MODEL CONVERGENCE PROPERTY MEAN-SQUARE ERROR

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AN ARCHITECTURE DESIGN APPROACH FOR LARGE SATELLITE NETWORKS

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 197-210页

作者： COTNER, C INUKAI, T COMSAT World Systems 6560 Rock Spring Drive Bethesda MD 20817 USA. Director Customer Technical Support for COMSAT World Systems. He directs support to U.S. users of the INTELSAT satellite network particularly in the areas of certifying that performance of earth-stations is in accordance with system requirements and in supporting the unique needs of television customers. Mr. Cotner's primary technical interests are earth-station design transmission analysis and high power amplifiers. Mr. Cotner has been with COMSAT for over 25 years. Most recently he served as Director of Technical Liaison and Analysis responsible for much of COMSAT World Systems research and development programme for high-level technical interaction with customers such as AT&T and MCI and for initiatives to improve the quality of international satellite transmission. He has also held technical management positions in COMSAT Laboratories COMSAT General where he was a Division Director Earth Segment Engineering and COMSAT World Systems where he represented the U.S. Signatory on the INTELSAT Board of Governors Technical Advisory Committee for five years. Mr. Cotner is a colonel (retired) in the Signal Corps U.S. Army Reserve where he was assigned to several mobilization positions related to satellite communications including a tour of duty on the Joint Staff. Awarded the degree of B.S.E. (cum-laude) in Electrical Engineering by Princeton University. Mr. Cotner also holds an M.S.E. from Cornell University and is a Commandants List graduate of the U.S. Army Command and General Staff College. He and his wife Sharon live in Silver Spring Maryland. COMSAT Laboratories 22300 COMSAT Drive Clarksburg MD 20871 USA. Received the BS and MS degrees in Communications Engineering from the Tokyo Electrical Engineering College Tokyo Japan and the Ph.D. degree in Electrical Engineering from the City University of New York New York. Dr. Inukai is a Principal Scientist in the Network Technology Division of COMSAT Laboratories. He directs res

Designing a world-wide satellite network that consists of hundreds of user sites and thousands of circuit connections is a complex problem, which involves selecting a set of candidate satellites and satellite beams/frequency bands from among numerous existing and planned satellites, evaluation of circuit connectivity, earth-station compatibility and sizing, and estimating transponder loading. The design process may also require assessment of the impact of a different set of satellites and modified user traffic requirements on the space segment, the earth-station types and quantity, and the total system cost. Although a conventional design approach based on link-by-link and site-by-site analysis provides accurate results, it is time-consuming and impractical for developing high-level network architectures in a time-constrained environment. A design technique is proposed which employs a set of rules for satellite network design, in combination with extensive databases of satellite parameters, earth-station parameters and user traffic requirements, to synthesize a network architecture. The technique is particularly useful for performing high-level trade-offs among alternative architectures in terms of space segment requirements, the number and type of earth-stations and overall system cost. Once the desired architecture has been selected, a detailed design may be developed using conventional methods.

关键词： SATELLITE NETWORK DESIGN RULE-BASED DESIGN FIXED SATELLITE SERVICES FDMA INTELSAT BANDWIDTH REQUIREMENTS TRANSPONDER CAPACITY

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Multisensory Fusion Algorithms for Tracking

Multisensory Fusion Algorithms for Tracking

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IEEE Regional Conference on Aerospace Control Systems

作者： L.Y. Pao S.D. O'Neil Signal Processing Department MITRE Corporation Bedford MA USA Investigation and Experimentation Program MITRE San Francisco CA USA

In this paper we extend a multitarget tracking algorithm for use in multisensory tracking situations. The algorithm we consider is Joint Probabilistic Data Association (JPDA). JPDA is extended to handle an arbitrary number of sensors under the assumption that the sensor measurement errors are independent across sensors. We also show how filtering can be handled in multisensory JPDA (MSJ PDA) without leading to an exponential increase in filtering complexity. Simulation results are presented comparing the performance of the MSJPDA with another multisensory fusion algorithm and with the single-sensor JPDA algorithm.

关键词： Gaussian noise Covariance matrix Time measurement State estimation Contracts Surveillance Current measurement Position measurement Sensor phenomena and characterization Measurement errors

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Interactive tools for signal processing education. The signal processing instructional facility (SPIF lab) at Washington State University

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Computer Applications in Engineering Education 1993年第6期1卷 517-517页

作者： Bamberger, R.H. Signal Processing Instructional Facility School of Electrical Engineering and Computer Science Washington State University Pullman WA 99164-2752 Dr. Roberto H. Bamberger:was born on January 30 1965 in Buenos Aires Argentina. He received his B.E.E and PhD from the Georgia Institute of Technology in 1986 and 1990 respectively. Currently Dr. Bamberger is an assistant professor in the School of Electrical Engineering and Computer Science at Washington State University. Dr. Bamberger's research program is focused on the design implementation and application of multidimensional multirate filter banks subband image and video compression analysis of nonstationary data and application of digital signal processing techniques in the design of analog and mixed-mode integrated circuits. Dr. Bamberger is the founder and director of the Signal Processing Instructional Facility (SPIF Lab) at Washington State University. The SPIF Lab features interactive multimedia-based tools for teaching concepts related to linear systems theory. Dr. Bamberger is active in developing multimedia-based instructional laboratories for a variety of other topics as well. In addition to his teaching and research programs Dr. Bamberger is an associate editor for theIEEE Transactions on Signal Processingand a member of the editorial board forComputer Applications in Engineering Education. Dr. Bamberger is also advisor to the WSU Student Branch of the IEEE and assistant director of the WSU Cougar Marching Band. Dr. Bamberger is a member of Phi Eta Sigma Eta Kappa Nu Tau Beta Pi and Kappa Kappa Psi.

The signal processing Instructional Facility (SPIF Lab) is an experiment in using in interactive multimedia for teaching concepts related to linear systems theory and signal processing. The goals of the SPIF lab are to augment, enhance, and interconnect sophomore, junior, and senior level courses with the common thread of linear systems and transforms by unifying the experimentation medium. In this fashion, physical phenomenon is returned to the forefront of engineering education. The laboratory features powerful Mathematica Notebooks (a form of hypertext) and interactive applications that use dedicated DSP microprocessors.

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FULL-WAVE SOLUTION OF DIELECTRIC LOADED WAVE-GUIDES AND SHIELDED MICROSTRIPS UTILIZING FINITE-DIFFERENCE AND THE CONJUGATE-GRADIENT METHOD

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INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE COMPUTER-AIDED ENGINEERING 1991年第4期1卷 346-357页

作者： NARAYANAN, V MANELA, M LADE, RK SARKAR, TK Department of Electrical and Computer Engineering Syracuse University Syracuse New York 13244-1240 Viswanathan Narayanan was born in Bangalore India on December 14 1965. He received the BE degree in Electronics and Communications from B.M.S. College of Engineering Bangalore in 1988. He joined the Department of Electrical Engineering at Syracuse University for his graduate studies in 1989 where he is currently a research assistant. His research interests are in microwave measurements numerical electromagnetics and signal processing. Biographies and photos are not available for M. Manela and R. K. Lade. Tapan K. Sarkar (Sf69-M'76-SM'X1) was born in Calcutta. India on August 2 1948. He received the BTech degree from the Indian Institute of Technology Kharagpur India in 1969 the MScE degree from the University of New Brunswick Fredericton Canada in 1971. and the MS and PhD degrees from Syracuse University. Syracuse NY in 1975. From 1975-1976 he was with the TACO Division of the General Instruments Corporation. He was with the Rochester Institute of Technology (Rochester NY) from 1976-1985. He was a Research Fellow at the Gordon Mckay Laboratory Harvard University Cambridge MA from 1977 to 1978. He is now a Professor in the Department of Electrical and Computer Engineering Syracuse University. His current research interests deal with numerical solutions of operator equations arising in electromagnetics and signal processing with application to system design. He obtained one of the “ best solution” awards in May 1977 at the Rome Air Development Center (RADC) Spectral Estimation Workshop. He has authored or coauthored more than 154 journal articles and conference papers and has written chapters in eight books. Dr. Sarkar is a registered professional engineer in the state of New York. He received the Best Paper Award of the IEEE Transactions on Electromagnetic Compatibility in 1979. He was an Associate Editor for feature articles of the lEEE Antennas arid Propagation Sociefy Newsletter and was

Dynamic analysis of waveguide structures containing dielectric and metal strips is presented. The analysis utilizes a finite difference frequency domain procedure to reduce the problem to a symmetric matrix eigenvalue problem. Since the matrix is also sparse, the eigenvalue problem can be solved quickly and efficiently using the conjugate gradient method resulting in considerable savings in computer storage and time. Comparison is made with the analytical solution for the loaded dielectric waveguide case. For the microstrip case, we get both waveguide modes and quasi-TEM modes. The quasi-TEM modes in the limit of zero frequency are checked with the static analysis which also uses finite difference. Some of the quasi-TEM modes are spurious. This article describes their origin and discusses how to eliminate them. Numerical results are presented to illustrate the principles.

关键词： Waveguides

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