http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Song, Iickho,Koo, Jinkyu,Kwon, Hyoungmoon,Park, So Ryoung,Lee, Sung Ro,Chung, Bo-Hyun IEEE 2005 IEEE Transactions on Vehicular Technology VT Vol.54 No.6
In this paper, we propose a novel criterion for the detection of weak m-ary signals. In the sense of minimizing the error probability, the proposed criterion is optimal when the signal strength approaches zero. Based on the proposed criterion, a detection scheme for ultrawideband multiple access systems is proposed and analyzed in the presence of impulsive interference. Numerical results show that the proposed detector requires less complexity than, and possesses almost the same performance as, the maximum likelihood detector. In impulsive interference, the proposed detector also offers significant performance improvement over the detector optimized for a Gaussian environment.
Youngkwon Ryu,Iickho Song,Taejoo Chang,Suk Chan Kim 한국정보과학회 1996 Journal of Electrical Engineering and Information Vol.1 No.1
Adaptive code rate change schemes in DS-SSMA systems are proposed. In the proposed schemes, the error correcting code rate is changed according to the channel states, Two channel stales having significant effects on the bit error probability are considered: one is the effective number of users, and the other is the fading environment. These channel states are estimated based on retransmission requests. The criterion for the change of the code rate is to maximize the throughput under given error bound.
Complexity-Reduced Scheme for Feature Extraction With Linear Discriminant Analysis
Yuxi Hou,Iickho Song,Hwang-Ki Min,Cheol Hoon Park IEEE 2012 IEEE transactions on neural networks and learning Vol.23 No.6
<P>Owing to the singularity of the within-class scatter, linear discriminant analysis (LDA) becomes ill-posed for small sample size (SSS) problems. Null-space-based LDA (NLDA), which is an extension of LDA, provides good discriminant performances for SSS problems. Yet, as the original scheme for the feature extractor (FE) of NLDA suffers from a complexity burden, a few modified schemes have since been proposed for complexity reduction. In this brief, by transforming the problem of finding the FE of NLDA into a linear equation problem, a novel scheme is derived, offering a further reduction of the complexity.</P>
Taehun An,Iickho Song,Hyoungmoon Kwon,Yun Hee Kim,Seokho Yoon,Jinsoo Bae IEEE 2009 IEEE Transactions on Vehicular Technology VT Vol.58 No.7
<P>In this paper, we propose a near maximum likelihood (ML) scheme for the decoding of multiple-input-multiple-output (MIMO) systems. By employing the metric-first search method, Schnorr-Euchner enumeration, and branch-length thresholds in a single frame systematically, the proposed technique provides efficiency that is higher than those of other conventional near-ML decoding schemes. From simulation results, it is confirmed that the proposed scheme has computational complexity lower than those of other near-ML decoders while maintaining the bit error rate (BER) very close to the ML performance. The proposed scheme, in addition, possesses the capability of allowing flexible tradeoffs between the computational complexity and BER performance.</P>
Taehun An,Iickho Song,Seungwon Lee,Hwang-Ki Min IEEE 2014 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS Vol.13 No.12
<P>We address detection schemes of spectrum sensing for cognitive radio with multiple receive antennas operating over a wideband channel composed of a multitude of subbands. By taking the observations in all subbands into consideration in the likelihood functions for sensing a subband, the test statistics of the proposed schemes are functions of the sample covariance matrix in the subband under consideration and that in the subband exhibiting the lowest power spectral density. The false alarm and detection probabilities of the proposed schemes are analyzed theoretically and confirmed via simulations when the numbers of observations are the same for all the subbands. It is shown through computer simulations that the proposed schemes can provide considerable performance gains over conventional schemes for wideband spectrum sensing when the observations are spatially correlated and temporally independent/dependent.</P>
Do, Thinh Phu,Song, Iickho,Kim, Yun Hee IEEE 2017 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS Vol.16 No.3
<P>We consider a simultaneous wireless transfer of information and power in a two-way relaying network, where a decode-and-forward protocol is employed for data exchange between two source devices at different rates. The data exchange is accomplished in two time phases (TPs) with possibly asymmetric TP ratios, where the relay is powered by the source devices in the first phase through simultaneous wireless information and power transfer (SWIPT) either by power splitting (PS) or by time switching (TS). For the network, resource allocation of the PS and TP ratios for the PS-based SWIPT and that of the TS and TP ratios for the TS-based SWIPT are studied to minimize the system outage probability. We first solve the joint optimization problem of each case with the instantaneous channel state information and then propose suboptimal schemes utilizing one or two values for the TP ratio to lower the implementation complexity. The results from analysis and simulation show that the proposed schemes outperform the benchmark scheme with equal resource allocation and that the gain gets more prominent as the rates of the data exchanged or the relay locations become more asymmetric.</P>