• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.11
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• pp.1054-1063
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• 2012

In this paper, we introduce basic theories, effects and applications of the unequal error protection (UEP) system that is expected to play a major role in the future multi-layered broadcast system. Also we show results of surveys on the various previous studies and standards about the UEP systems, and we give prospects of standardizations and future applications of UEP based on the surveys.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.4
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• pp.206-208
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• 2014

In this letter, IQ mismatch of a CA-supporting terminal for LTE-A is analyzed and each of the analog blocks is modeled mathematically. Based on the model, a new digital calibration algorithm is proposed and verified using simulation results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.4
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• pp.212-214
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• 2014

In this paper, we present the scenario designs of the possibility of space communications for Korean Lunar Explorer and the analysis of its performance, depending upon the explorer's position within the moon's orbit after being launched from earth. As per each scenario, we would like to propose the analysis of the possible communication times and total transmission throughput data per day in two cases: one for using DSN and another for using only Korean's ground station.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.3
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• pp.224-239
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• 2013

An exact performance analysis of an ML detector for a 2-dimensional rotation-transform aided QPSK system operating over an impulsive noise environment is presented using Rieman integrals of a two-dimensional Gaussian Q-function over Voronoi cells. A set of interesting features of the Voronoi cells is also characterised systematically. An optimum rotation angle yielding the minimum BER is also studied. The differences between the proposed exact method and the previous approximate analysis method are investigated in terms of the corresponding BERs and the derived optimum angles.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.5
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• pp.454-463
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• 2013

The smart phone has already proliferated, and the smart devices of the living appliances and vehicles embedded with communication device, sensors and connected with the smart phone have been developed. Currently it can provide simple remote controller and user interfaces, it could be envisaged that intelligent technology is converged with the smart phone, and Personal Environment Service in which the smart devices are configured automatically as reflecting personal preference, device attribute, and living environment condition would be activated in the future. In this paper PES services, system architecture, and core technology are described.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.11
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• pp.976-978
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• 2013

In this paper, we address data transmission systems using multiple linear polarized antennas over pure line-of-sight (LoS) wireless channels. We investigate the impact of antenna angles from the perspective of both channel capacity and error performance. We show that the optimal angles from the two perspectives are different, and evaluate the performance of the two optimal angles.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.11
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• pp.979-981
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• 2013

In this paper, this study is aimed how to estimate the position of scattered pilot to be used to estimate channel in the OFDM System. The proposed method is possible to estimate the accurate position of scattered pilot to remove the phase error through cross-correlation between received signal and 4 symbol delay received signal.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.11
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• pp.973-975
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• 2013

In this paper, the carrier-to-noise power ratio estimation performances for commercial GPS receiver are shown by simulation and are analyzed under weak signal reception, high sensitivity signal reception, and the matched spectrum jamming signal reception environments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.11
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• pp.967-969
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• 2013

In this paper, we propose an efficient mult-signature scheme based on a bilinear mapping for shared data in the cloud and prove the security of the proposed scheme using the difficulty of the computational Diffie-Hellman problem. For verification, the scheme is using the sum of the hash values of stored data rather than the entire data, which makes it feasible to reduce the size of the downloaded data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.11
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• pp.938-943
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• 2013

In this paper, we propose a transmission parameter optimization scheme based on genetic algorithm for dynamic spectrum access systems. Specifically, we represent a multiple objective fitness function as a weighted sum of single objective fitness functions to optimize transmission parameters, and then, obtain optimized transmission parameters based on genetic algorithm for given transmission scenarios. From numerical results, we confirm that the transmission parameters are well optimized by using the proposed optimization scheme.