• Title/Summary/Keyword: Multichannel

Search Result 512, Processing Time 0.023 seconds

An Efficient Representation Method for ICLD with Robustness to Spectral Distortion

  • Beack, Seung-Kwon;Seo, Jeong-Il;Kang, Kyung-Ok;Hanh, Min-Soo
    • ETRI Journal
    • /
    • v.27 no.3
    • /
    • pp.330-333
    • /
    • 2005
  • The Inter-Channel Level Difference (ICLD) is a cue parameter to estimate spectral information in a binaural cue coding that has been recently in the spotlight as a multichannel audio signal compression technique. Even though the ICLD is an essential parameter, it is generally distorted by quantization. In this paper, a new modified ICLE representation method to minimize the quantization distortion is proposed by adopting a flexible determination of the reference channel and the unidirectional quantization. Our experimental result confirms that the proposed method improves the multichannel audio output quality even with the reduced bit-rate.

  • PDF

Effect of Open Channels on the Isolation of Overlapping Resonances in the Uniformly Perturbed Rydberg Systems Studied by Multichannel Quantum Defect Theory

  • Lee, Chun-Woo;Kim, Jeong-Jin
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.5
    • /
    • pp.1519-1526
    • /
    • 2011
  • A previous study (Lee, C. W. J. Phys. B 2010, 43, 175002) that isolated the overlapping resonances in the photoionization spectra using multichannel quantum defect theory (MQDT) in systems involving a single open channel was extended to manage many open channels when the closed channels are degenerate. The theory was applied to the dipole allowed J = 1$^{\circ}$ spectra from the ground state with excitation energies lying between the lowest ionization thresholds for rare gas atoms, Ar, Kr, and Xe, and also for group IV elements, Ge, Sn and Pb.

Study of the Resonance Structures of the Preionizing Spectrum of Molecular Hydrogen by Phase-Shifted Multichannel Quantum Defect Theory II

  • Lee, Chun-Woo
    • Bulletin of the Korean Chemical Society
    • /
    • v.33 no.8
    • /
    • pp.2657-2668
    • /
    • 2012
  • We obtain the general formulation which can handle the rotational preionization spectrum of $H_2$ in the region above its ${H_2}^+$ ionization threshold, ($^2{\sum}_g^+$, ${\nu}^+=0$, $N^+=0$) converging toward its rotationally excited (${\nu}^+=0$, $N^+=2$) limit and perturbed by the vibrationally excited levels $7p{\pi}$ ${\nu}=1$ and $5p{\pi}$ ${\nu}^=2$. The formulation is based on phase-shifted multichannel quantum-defect theory. With this formulation, resonance structures are analyzed in detail.

The Lecomte-Ueda Transformation and Resonance Structure in the Multichannel Quantum Defect Theory for the Two Open and One Closed Channel System

  • Lee, Chun-Woo;Kim, Ji-Hyun
    • Bulletin of the Korean Chemical Society
    • /
    • v.23 no.11
    • /
    • pp.1560-1567
    • /
    • 2002
  • The transformation devised by Lecomte and Ueda for the study of resonance structures in the multichannel quantum defect theory (MQDT) is used to analyze partial photofragmentation cross section formulas in MQDT analogous to Fano's resonance formula obtained in the previous work for the system involving two open and one closed channels. Detailed comparison of the MQDT results with the configuration mixing (CM) ones is made. Resonance structures and their geometrical relations in the MQDT formulation are revealed and classified by combining Lecomte and Ueda's theory with the geometrical method devised to study the coupling between background and resonance scatterings.

Blind Adaptive Channel Estimation using Multichannel Linear Prediction (다채널 선형예측을 이용한 블라인드 적응 채널 추정)

  • 조주필;안경승;황지원
    • Journal of Korea Multimedia Society
    • /
    • v.6 no.1
    • /
    • pp.114-120
    • /
    • 2003
  • Blind channel estimation of communication channels is a problem of important current theoretical concerns. Recently proposed solutions for this problem exploit the diversity induced by antenna array or time oversampling, leading to the so-called, second order statistics techniques. This paper proposes the blind adaptive channel estimation using multichannel linear prediction method. Computer simulations are presented to compare the proposed algorithm with the existing ones.

  • PDF

Overview of MPEG Surround (MPEG Surround 표준화 동향 및 기술 분석)

  • Jang In-Seon;Beack Seung-Kwon;Seo Jeong-Il;Jang Dae-Young
    • Journal of Broadcast Engineering
    • /
    • v.11 no.2 s.31
    • /
    • pp.181-190
    • /
    • 2006
  • Technology for compressing low-bitrate multichannel audio coding should be developed owing to the increasing need of consumer for multichannel audio contents and services. To meet this requirement, MPEG has standardized MPEG Surround. In this paper, we introduce status on MPEG Surround standardization and analyze techniques adopted in the current MPEG Surround.

Early Reflection Generation Technique in Stereo-to-Multichannel Upmix System (스테레오-멀티채널 업믹스 시스템에서의 초기 반사음 생성 기법)

  • Lee, Taegyu;Baek, Yong-Hyun;Park, Young-Cheol;Youn, Dae Hee
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2013.06a
    • /
    • pp.8-11
    • /
    • 2013
  • 스테레오-멀티채널 업믹스(Stereo-to-Multichannel Upmix)기술은 시장의 대부분을 차지하는 스테레오 음원을 홈시어터와 같은 멀티채널 스피커 재생 환경에서 효과적으로 재생하기 위한 채널 포맷 변환 기술을 말한다. 수평적인 공간감뿐만 아니라 수직적인 공간감을 재현하기 위하여 10.2, 22.2채널 환경의 경우 고도 채널이 추가되었다. 본 논문에서는 이러한 채널 환경에서 수직, 수평적인 공간감을 재현하기 위하여 새로운 초기 반사음을 생성하는 알고리즘을 제안하였다. 제안된 알고리즘은 진폭 패닝방법을 이용하여 전방의 가상 음원들에 의하여 발생되는 리시버 위치에서의 음압을 일치시킴으로써 기존 알고리즘이 가지지 못했던 이론적인 배경을 갖는다. 청취 평가 실험을 통하여 제안된 알고리즘은 음장의 수직, 수평적인 폭을 증가시키며, 좀 더 안정적인 음상 정위 성능을 가지는 것을 확인하였다.

  • PDF