• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2016.06a
• /
• pp.275-277
• /
• 2016

본 논문은 human visual system(HVS)에 따른 주파수 민감도와 공간에서 다양한 특성들을 구현하기 위한 신호처리 방법을 개발하였다. 인간의 눈은 주파수 성분에 따라 민감도가 다르며 초점에서 멀수록 인지 가능한 해상도가 떨어진다. 주파수 민감도를 구현하기 위해서 본 논문은 영상 신호의 에너지 스펙트럼 모양이 contrast sensitivity function(CSF)의 모양이 되도록 하여 영상 신호의 에너지를 증가시켰으며 신호 방향에 적응적인 multiband energy scaling 방법을 개발하였다. 기존의 시스템에서 능률만을 향상시키는 기존의 분석 모델과 비교하면 개발한 방법은 HVS에 좀 더 적절하고 선호되게 영상 신호를 처리할 수 있다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2011.07a
• /
• pp.417-419
• /
• 2011

근래 다양한 형태의 멀티미디어 콘텐츠가 광범위하게 소비됨에 따라 단방향의 평면적 콘텐츠가 제공하는 시점의 한계에서 벗어나 사용자에게 보다 다양한 시점의 영상을 제공함으로써 사용자가 원하는 시점을 선택할 수 있는 실감형 콘텐츠에 대한 욕구가 증가하고 있다. 이러한 실감형 콘텐츠 중 하나인 파노라마 영상은 다수의 카메라를 통해 획득된 영상들을 하나의 영상으로 이어 붙여 넓은 시야의 영상을 제공함으로써 증대된 현장감과 몰입감을 제공하며 사용자 시점의 자유도를 증가시킬 수 있다. 본 고에서는 다수 영상의 스티칭 시 발생하는 고스팅 영향(ghosting effect)를 최소화 하기 위한 칼럼 시차 최소화 (Column Disparity Minimaization)기반의 멀티밴드 블랜딩(Multiband blending)을 소개 하고자 한다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.6 no.4
• /
• pp.616-623
• /
• 2002

The fractal expanded antenna with the configuration of a triangular microstrip patch antenna is presented and analyzed. In the fundamental and higher mode of TFA(Triangular Fractal Antenna), resonant frequencies are controlled by changing the scaling factor. It is observed that increasing scaling factor makes the resonant frequency be spread, and decreasing scaling factor makes it be concentrated. The scaling factor is varied as the expansion and concentration of resonant frequencies. The resonant frequency in each fractal patch element is observed log -periodically. The TFA can be applied to the multiband system.

• Proceedings of the KOSOMBE Conference
• /
• v.1997 no.05
• /
• pp.342-344
• /
• 1997

Owing to technical advances in very large-scale integrated circuits (VLSI), high-speed digital signal processing (DSP) chips become fast enough to allow for real-time implementation of hearing aid algorithms in units small enough to be wearable. In this paper, we present a digital hearing aid processor (DHAP) chip built around a general-purpose 16-bit DSP core. The designed DHAP performs a nonlinear loudness correction of 8 octave frequency bands based on audiometric measurements. By employing a programmable DSP, the DHAP provides all the flexibility needed to implement audiological algorithms. In addition, the has a low power feature and $5.410\times5.720mm^2$ dimensions that fit for wearable devices.

• Journal of Astronomy and Space Sciences
• /
• v.6 no.2
• /
• pp.75-89
• /
• 1989

The Spacelab 1 data represented the first multiband spectral measuremets of the ${N_2}^{+}$ first negative ion bands system in the thermospheric dayglow, and the first opportunity to make a detailed comparison of the vibrational and rotational distributions over bands out to v'=5. The main purpose of this study was to decuced the excitation processes of ${N_2}^{+}$(1N) bands by determining vibrational population distributions for the upper states of ${N_2}^{+}$(1N). The vibrational population distributions to achieve a best fit to the measured Spacelab 1 data were summarized and also compared with those theoretically derived.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.11
• /
• pp.2375-2380
• /
• 1997

The need for developing effective coding techniques for various multimedia services is increasing in order to meet the demand for image data. In this paper, a zeroblock coding algorithm is proposed for progressive transmission of images. The zeroblock coding algorithm is constructed as an embedded coding so that the encoding and decoding process can be terminated at any point and allowing reasonable image quality. Some features of zeroblock coding algorithm are 1) coding of subband images by prediction of the insignificance of blocks across subband leels, 2) aset of sate transition rules for representing the significance map of blocks, and 3) block coding by vector quantization using a multiband codebook consisting of several subcodebooks dedicated for each subband at a given threshold.

• Journal of the Optical Society of Korea
• /
• v.12 no.1
• /
• pp.42-48
• /
• 2008

The relative intensity noise (RIN) characteristics in 405 nm blue laser diodes grown on wurtzite AlGaInN multiple quantum well structures were investigated using the rate equations with the quantum Langevin noise model. The device parameters were extracted from the optical gain properties of the MQW active region using the self-consistent numerical method developed for calculating the multiband Hamiltonian in the strained wurtzite crystal. These methods have been applied to laser diodes for various conditions including the external feedback and the high frequency current injection.

• ETRI Journal
• /
• v.35 no.6
• /
• pp.1126-1133
• /
• 2013

The first spectrum auction in the Republic of Korea is attention-worthy owing to the fierce competition for the only 1.8-GHz spectrum license, the winning bidder of which was suspected of overpaying for its acquisition. This study empirically investigates the existence of a "winner's curse" in the first Korean spectrum auction by using a standard event study methodology. The results show that both the winner and loser experienced significant positive returns on the completion day of the auction. The results imply that there was no winner's curse in the auction and that the losing firm might increase its competitive advantage by acquiring other spectrum licenses despite failing to achieve its initial target spectrum. Therefore, these results suggest that regulators may need to consider bringing about positive short-term wealth benefits to all bidders by appropriately designing a spectrum auction, such as by performing multiband auctions.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.12 no.4
• /
• pp.469-475
• /
• 2009

TMMR(Tactical Multiband Multirole Radio) is one of the important equipments for TICN which is our next military tactical communication system and it supplies to the distribution of traffic of C2(Command & Control) and SA(Situation Awareness) for unit of Brigade and below. In this paper, we define the tactical needs of military communication, and evaluate MANET(Mobile Ad-hoc Network) protocol for the future digital battle-field through performance comparison with a network simulator.

• Journal of electromagnetic engineering and science
• /
• v.15 no.4
• /
• pp.239-244
• /
• 2015

A simple planar heptaband antenna with a coupling feed for 4G mobile applications is proposed. This antenna consists of a folded monopole and a feed strip line on the top plane and an L-shaped line with a coupling plate on the bottom plane. The antenna provides a wide bandwidth to cover the LTE/GSM/UMTS heptaband operation. The measured 6-dB return loss bandwidth is 152 MHz (820-972 MHz) in the lowfrequency band and 1,150 MHz (1,600-2,750 MHz) in the high-frequency band. The overall dimensions of the proposed antenna are $60mm{\times}105mm{\times}1.2mm$.