Browsing by Author "LIN, DW"

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AN EFFICIENT FSE DFE-BASED HDSL EQUALIZER WITH NEW ADAPTIVE ALGORITHMS
(1994)
HWANG, CJ
;
TANG, TC
;
LIN, DW
;
CHEN, SG
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電子工程學系及電子研究所
AN IMAGE COMPRESSION SCHEME FOR DIGITAL VIDEO CASSETTE RECORDING
(1994)
CHENG, JB
;
HANG, HM
;
LIN, DW
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
ENHANCEMENT OF IMAGE QUALITY FOR LOW BIT RATE VIDEO CODING
(1991-10-01)
NGAN, KN
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LIN, DW
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LIOU, ML
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交大名義發表
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National Chiao Tung University
CCITT Recommendation H.261 on coding for visual telephony is applicable to bit rates of p X 64 kbits/s, where p = 1,2,..., 30. It generally performs well over the intended bit rates. However, at the very low rates of 64 and 128 kbits/s, it suffers from visual degradation due to coarse quantization. In this paper, we studied the various approaches or combinations of them to improve the image quality. Methods studied include reducing the quantizer step size, randomized scanning of the macroblocks, and/or nonuniform quantization of the transform coefficients.
FRACTAL IMAGE CODING AS GENERALIZED PREDICTIVE CODING
(1994)
LIN, DW
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
MINIMUM MEAN-SQUARED ERROR DECISION-FEEDBACK EQUALIZATION FOR DIGITAL SUBSCRIBER LINE TRANSMISSION WITH POSSIBLY CORRELATED LINE CODES
(1991-08-01)
LIN, DW
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電子工程學系及電子研究所
;
電信研究中心
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Department of Electronics Engineering and Institute of Electronics
;
Center for Telecommunications Research
Most of the published theory on the optimal performance of decision-feedback equalization under the MMSE criterion addresses the transmission of i.i.d. symbol sequences only. This paper presents a theory which accommodates the case of correlated symbol sequences. It also considers the use of a fractionally spaced forward filter in the decision-feedback equalizer (DFE). Two limiting conditions are discussed in some detail, both concerning having an infinite-length DFE feedback filter. In one of them the forward filter is of finite length and in the other it is noncausal infinite. Several numerical examples are given, in which we apply the theory to the study of the MMSE transmission performance, at ISDN basic access rates, of a few example subscriber lines using some well-known line codes. In these examples, the near-end crosstalk from identical digital transmission systems is assumed to be the only significant noise. Throughout the study, we ignore the effects of error propagation in a DFE.
MOTION RESTORATION - A METHOD FOR OBJECT AND GLOBAL MOTION ESTIMATION
(1994)
SU, JS
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HANG, HM
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LIN, DW
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
VIDEO ON PHONE LINES - TECHNOLOGY AND APPLICATIONS
(1995-02-01)
LIN, DW
;
CHEN, CT
;
HSING, TR
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電子工程學系及電子研究所
;
電信研究中心
This paper reviews the telephone loop plant characteristics, current DSL (digital subscriber line) technologies, recent efforts in video coding standards, and the interrelationship between DSL technologies and visual communications over subscriber lines. In overview of the loop plant characteristics we examine its physical makeup and transmission properties, where for the latter we discuss frequency and time responses of wire-pair lines and the impairments of echo, crosstalk, impulse noise, and radio frequency interference. We trace the historical development of various DSL technologies and comment on possible future evolution. Transmission technologies used in the ISDN basic-access DSL, the high bit-rate DSL, and the asymmetric DSL are portrayed. And the issue of spectrum compatibility among different transmission systems is explained. Several important video coding standards are briefly described, including ITU-T's H.261 and ISO's JPEG and MPEG series, which are either completed or emerging. The synergistic relationship between these standards and the DSL technologies is elucidated. As a result, DSL technologies provide the potential of delivering certain broadband services well in advance of direct fiber access for telephone subscribers.