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Goswami K.,Sun Moon University | Kim B.-G.,Sun Moon University | Jun D.,Broadcasting and Telecommunications Media Research Laboratory | Jung S.-H.,Broadcasting and Telecommunications Media Research Laboratory | Choi J.S.,Broadcasting and Telecommunications Media Research Laboratory
ETRI Journal | Year: 2014

A new-generation video coding standard, named High Efficiency Video Coding (HEVC), has recently been developed by JCT-VC. This new standard provides a significant improvement in picture quality, especially for high-resolution videos. However, one the most important challenges in HEVC is time complexity. A quadtree-based structure is created for the encoding and decoding processes and the rate-distortion (RD) cost is calculated for all possible dimensions of coding units in the quadtree. This provides a high encoding quality, but also causes computational complexity. We focus on a reduction scheme of the computational complexity and propose a new approach that can terminate the quadtree-based structure early, based on the RD costs of the parent and current levels. Our proposed algorithm is compared with HEVC Test Model version 10.0 software and a previously proposed algorithm. Experimental results show that our algorithm provides a significant time reduction for encoding, with only a small loss in video quality. © 2014 ETRI.


Seok J.M.,Broadcasting and Telecommunications Media Research Laboratory | Lee Y.,Agency for Defense Development
ETRI Journal | Year: 2014

In the near future, traditional narrow and fixed viewpoint video services will be replaced by high-quality panorama video services. This paper proposes a visualattention-aware progressive region of interest (RoI) trick mode streaming service (VA-PRTS) that prioritizes video data to transmit according to the visual attention and transmits prioritized video data progressively. VA-PRTS enables the receiver to speed up the time to display without degrading the perceptual quality. For the proposed VA-PRTS, this paper defines a cutoff visual attention metric algorithm to determine the quality of the encoded video slice based on the capability of visual attention and the progressive streaming method based on the priority of RoI video data. Compared to conventional methods, VA-PRTS increases the bitrate saving by over 57% and decreases the interactive delay by over 66%, while maintaining a level of perceptual video quality. The experiment results show that the proposed VA-PRTS improves the quality of the viewer experience for interactive panoramic video streaming services. The development results show that the VA-PRTS has highly practical real-field feasibility. © 2014 ETRI.


Jeong J.-C.,Broadcasting and Telecommunications Media Research Laboratory | Jang D.-P.,Broadcasting and Telecommunications Media Research Laboratory | Han B.-G.,Radar Corporation | Yom I.-B.,Broadcasting and Telecommunications Media Research Laboratory
ETRI Journal | Year: 2014

A C-band 50 W high-power microwave monolithic integrated circuit amplifier for use in a phased-Array radar system was designed and fabricated using commercial 0.25 μm AlGaN/GaN technology. This two-stage amplifier can achieve a saturated output power of 50 W with higher than 35% power-Added efficiency and 22 dB small-signal gain over a frequency range of 5.5 GHz to 6.2 GHz. With a compact 14.82 mm2 chip area, an output power density of 3.2 W/mm2 is demonstrated. © 2014 ETRI.


Park U.,Broadcasting and Telecommunications Media Research Laboratory | Kim H.W.,Broadcasting and Telecommunications Media Research Laboratory | Oh D.S.,Broadcasting and Telecommunications Media Research Laboratory | Ku B.-J.,Broadcasting and Telecommunications Media Research Laboratory
ETRI Journal | Year: 2014

An integrated multi-beam satellite and multi-cell terrestrial system is an attractive means for highly efficient communication due to the fact that the two components (satellite and terrestrial) make the most of each other's resources. In this paper, a terrestrial component reuses a satellite's resources under the control of the satellite's network management system. This allows the resource allocation for the satellite and terrestrial components to be coordinated to optimize spectral efficiency and increase overall system capacity. In such a system, the satellite resources reused in the terrestrial component may bring about severe interference, which is one of the main factors affecting system capacity. Under this consideration, the objective of this paper is to achieve an optimized resource allocation in both components in such a way as to minimize any resulting inter-component interference. The objective of the proposed scheme is to mitigate this intercomponent interference by optimizing the total transmission power - the result of which can lead to an increase in capacity. The simulation results in this paper illustrate that the proposed scheme affords a more energyefficient system to be implemented, compared to a conventional power management scheme, by allocating the bandwidth uniformly regardless of the amount of interference or traffic demand. © 2014 ETRI.


Chung T.J.,Broadcasting and Telecommunications Media Research Laboratory | Lee W.-H.,Broadcasting and Telecommunications Media Research Laboratory
ETRI Journal | Year: 2013

A 10-Gbit/s wireless communication system operating at a carrier frequency of 300 GHz is presented. The modulation scheme is amplitude shift keying in incoherent mode with a high intermediate frequency (IF) of 30 GHz and a bandwidth of 20 GHz for transmitting a 10-Gbit/s baseband (BB) data signal. A single sideband transmission is implemented using a waveguide-tapered 270-GHz highpass filter with a lower sideband rejection of around 60 dB. This paper presents an all-electronic design of a terahertz communication system, including the major modules of the BB and IF band as well as the RF modules. The wireless link shows that, aided by a clock and data recovery circuit, it can receive 27-1 pseudorandom binary sequence data without error at up to 10 Gbit/s for over 1.2 m using collimating lenses, where the transmitted power is 10 μW. © 2013 ETRI.


Jeong J.-C.,Broadcasting and Telecommunications Media Research Laboratory | Jang D.-P.,Broadcasting and Telecommunications Media Research Laboratory | Yom I.-B.,Broadcasting and Telecommunications Media Research Laboratory
ETRI Journal | Year: 2013

A Ka-band 6-W high power microwave monolithic integrated circuit amplifier for use in a very small aperture terminal system requiring high linearity is designed and fabricated using commercial 0.15-μm GaAs pHEMT technology. This three-stage amplifier, with a chip size of 22.1 mm2 can achieve a saturated output power of 6 W with a 21% power-added efficiency and 15-dB small signal gain over a frequency range of 28.5 GHz to 30.5 GHz. To obtain high linearity, the amplifier employs a class-A bias and demonstrates an output third-order intercept point of greater than 43.5 dBm over the above-mentioned frequency range. © 2013 ETRI.


Kim Y.,Broadcasting and Telecommunications Media Research Laboratory | Jun D.,Broadcasting and Telecommunications Media Research Laboratory | Jung S.-H.,Broadcasting and Telecommunications Media Research Laboratory | Choi J.S.,Broadcasting and Telecommunications Media Research Laboratory | Kim J.,Broadcasting and Telecommunications Media Research Laboratory
ETRI Journal | Year: 2013

A fast intra-prediction method is proposed for High Efficiency Video Coding (HEVC) using a fast intra-mode decision and fast coding unit (CU) size decision. HEVC supports very sophisticated intra modes and a recursive quadtree-based CU structure. To provide a high coding efficiency, the mode and CU size are selected in a ratedistortion optimized manner. This causes a high computational complexity in the encoder, and, for practical applications, the complexity should be significantly reduced. In this paper, among the many predefined modes, the intra-prediction mode is chosen without rate-distortion optimization processes, instead using the difference between the minimum and second minimum of the rate-distortion cost estimation based on the Hadamard transform. The experiment results show that the proposed method achieves a 49.04% reduction in the intra-prediction time and a 32.74% reduction in the total encoding time with a nearly similar coding performance to that of HEVC test model 2.1. © 2013 ETRI.


Lee Y.S.,Broadcasting and Telecommunications Media Research Laboratory | Byun W.,Broadcasting and Telecommunications Media Research Laboratory
IEEE Microwave and Wireless Components Letters | Year: 2014

This letter considers the effect of the eccentricity on the static field and charge distribution for a circular aperture pierced by a long cylinder. The conformal mapping method is used to convert the problem of an eccentric aperture into that of a concentric aperture. The Weber transform, superposition principle, and mode matching are employed to calculate the static potential for this concentric problem. Numerical computations illustrate the behavior of potential distribution, surface charge density, and partial charges on the plane for various aperture eccentricities. © 2001-2012 IEEE.


Kang K.-M.,Broadcasting and Telecommunications Media Research Laboratory | Park J.,Broadcasting and Telecommunications Media Research Laboratory
IEEE Transactions on Consumer Electronics | Year: 2014

This paper presents a cognitive radio system (CRS) that complies with the maximum allowable transmit power and emission limits of TV band devices (TVBDs). The CRS consists of a TVBD that uses the existing Wi-Fi module and two Wi-Fi modules operating in the 2.4 GHz and 5 GHz bands. Design methods are proposed for a radio frequency (RF) module, a digital signal processing (DSP) module, and a circuit for transmit-receive mode switching in the TV band device (TVBD). The performance of the implemented TVBD is investigated in both wired and wireless environments. The measured data rates of the implemented TVBD at the application layer are approximately 60 % of the theoretical data rates at the physical layer in the Wi-Fi system. The service coverage of a TVBD network is also measured according to several modulation and coding schemes (MCSs) of the TVBD for a single spatial stream. The coverage measurements of a TVBD network are conducted in both a suburban area, Jeju Island, and a nearly open area, Incheon, South Korea. The results show that the service coverage of a mobile network in TV white space (TVWS) can be enlarged by more than 2 km in the suburban area and by more than 8 km in the nearly open area. © 2015 IEEE.


Hahm G.-J.,Broadcasting and Telecommunications Media Research Laboratory | Cho K.,Broadcasting and Telecommunications Media Research Laboratory
International Conference on ICT Convergence 2015: Innovations Toward the IoT, 5G, and Smart Media Era, ICTC 2015 | Year: 2015

Event detection using webcast text is an important function for providing event based video segmenting services of sport videos. In this paper, an approach of webcast event clustering for sport video event annotation is proposed. In our approach, one of unsupervised learning algorithms, called pLSA (probabilistic latent semantic analysis), is used to classify event types. To decide an appropriate number of event types, lexical pattern analysis is used. By the experimental results, it is observed that our approach could be used to extract event keywords from the basketball webcast texts. © 2015 IEEE.

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