Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Journal of Korean Institute of Communications and Information Sciences
Journal Basic Information
Journal DOI :
The Korean Institute of Communications and Information Sciences
Editor in Chief :
Volume & Issues
Volume 33, Issue 12C - Dec 2008
Volume 33, Issue 12B - Dec 2008
Volume 33, Issue 12A - Dec 2008
Volume 33, Issue 11C - Nov 2008
Volume 33, Issue 11B - Nov 2008
Volume 33, Issue 11A - Nov 2008
Volume 33, Issue 10C - Oct 2008
Volume 33, Issue 10B - Oct 2008
Volume 33, Issue 10A - Oct 2008
Volume 33, Issue 9C - Sep 2008
Volume 33, Issue 9B - Sep 2008
Volume 33, Issue 9A - Sep 2008
Volume 33, Issue 8C - Aug 2008
Volume 33, Issue 8B - Aug 2008
Volume 33, Issue 8A - Aug 2008
Volume 33, Issue 7C - Jul 2008
Volume 33, Issue 7B - Jul 2008
Volume 33, Issue 7A - Jul 2008
Volume 33, Issue 6C - Jun 2008
Volume 33, Issue 6B - Jun 2008
Volume 33, Issue 6A - Jun 2008
Volume 33, Issue 5C - May 2008
Volume 33, Issue 5B - May 2008
Volume 33, Issue 5A - May 2008
Volume 33, Issue 4C - Apr 2008
Volume 33, Issue 4B - Apr 2008
Volume 33, Issue 4A - Apr 2008
Volume 33, Issue 3C - Mar 2008
Volume 33, Issue 3B - Mar 2008
Volume 33, Issue 3A - Mar 2008
Volume 33, Issue 2A - Feb 2008
Volume 33, Issue 2C - Feb 2008
Volume 33, Issue 2B - Feb 2008
Volume 33, Issue 1C - Jan 2008
Volume 33, Issue 1B - Jan 2008
Volume 33, Issue 1A - Jan 2008
Selecting the target year
Design of MuIti-Weight 2-Dimensional Optical Orthogonal Codes
Piao, Yong-Chun ; Shin, Dong-Joon ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 1~5
Optical code division multiple access(OCDMA) systems make the active users to share the bandwidth by simply assigning distinct optical orthogonal codeword to each active user. An optical orthogonal code(OOC) is a collection of binary sequences with good correlation properties which are important factors of determining the capacity of OCDMA systems. Recently, 2-D OOC construction method is frequently researched which is able to support more users than 1-D OOC. In this paper, a combinatorial construction of simple multi-weight 2-D OOC with autocorrelation 0 and crosscorrelation 1 is proposed and the bound on the size of these codes is derived.
Linear Complexity of 1-Symbol Insertion Sequences from m-Sequences
Chung, Jin-Ho ; Yang, Kyeong-Cheol ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 6~11
From a periodic sequence, we can obtain new sequences with a longer period by r-symbol insertion to each period. In this paper we review previous results on the linear complexity of periodic sequences obtained by r-symbol insertion. We derive the distribution of the linear complexity of 1-symbol insertion sequences obtained from m-sequences over GF(p), and prove some relationship between their linear complexity and the insertion position. Then, we analyze the k-error linear complexity of the 1-symbol insertion sequences from binary m-sequences.
New Non-linear Inverse Quantization Algorithm and Hardware Architecture for Digital Audio Codecs
Moon, Jong-Ha ; Baek, Jae-Hyun ; SunWoo, Myung-Hoon ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 12~18
This paper This paper proposes a new inverse-quantization(IQ) table interpolation algorithm, specialized Digital Signal Processor(DSP) instructions and hardware architecture for digital audio codecs. Non-linear inverse quantization algorithm is representatively used in both MPEG-1 Layer-3 and MPEG-2/4 Advanced Audio Coding(AAC). The proposed instructions are optimized for the non-linear inverse quantization. The proposed algorithm can minimize operational complexity which reduces total computational load. Performance comparisons show a significant improvement of average error. The proposed instructions and hardware architecture can reduce 20% of the instruction counts and minimize computational loads of IQ algorithms effectively compared with existing IQ table interpolation algorithms. Proposed algorithm can implement commercial DSPs.
Adaptive Selection of Fast Block Matching Algorithms for Efficient Motion Estimation
Kim, Jung-Jun ; Jeon, Gwang-Gil ; Jeong, Je-Chang ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 19~33
A method that is adaptively selecting among previous fast motion estimation algorithms and a newly proposed fast motion estimation algorithm(UCDS) is presented in this paper. The algorithm named AUDC and a newly proposed fast motion estimation algorithms are based on the Diamond Search(DS) algorithm and Three Step Search(TSS). Although many previous fast motion estimation algorithms have lots of advantages, those have lots of disadvantages. So we thought better adaptive selection of fast motion estimation algorithms than only using one fast motion estimation algorithm. Therefore, we propose AUDC that is using length of the MV, Search Point, SAD of the neighboring block and adaptively selecting among Cross Three Step Search(CTSS), Diamond Search(DS) and Ungraded Cross Diamond Search(UCDS). Experimental results show that the AUDC is much more robust, provides a faster searching speed, and smaller distortions than other popular fast block-matching at algorithms.
A Rate-Distortion Estimation Method for Fast Mode Decision in H.264
Moon, Jeong-Mee ; Kim, Jae-Ho ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 34~44
In this paper, a new rate-distortion estimation method is proposed for fast rate-distortion optimized(RDO) mode decision in H.264 encoder. A bit-rate and distortion should be calculated by encoding and reconstruction of each macroblock mode in order to select the optimal RDO mode. To reduce the computations for getting them, a bit-rate and distortion is efficiently estimated in DCT domain. Simulation results show that the proposed method achieves computational saving about 81% of RDO mode decision and saves about 26% of total encoding time without noticeable degradation in coding performance.
Histogram Matching Algorithm for Content-Based Dnage Retrieval
You, Kang-Soo ; Yoo, Gi-Hyoung ; Kwak, Hoon-Sung ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 45~52
In this paper, we describe the Perceptually Weighted Histogram(PWH) and the Gaussian Weighted Histogram Intersection(GWHI) algorithms. These algorithms are able to provide positive results in image retrieval. But these histogram methods alter the histogram of an image by using particular lighting conditions. Even two pictures with little differences in lighting are not easily matched. Therefore, we propose that the Histogram Matching Algorithm(HMA) is able to overcome the problem of an image being changed by the intensity or color in the image retrieval. The proposed algorithm is insensitive to changes in the lighting. From the experiment results, the proposed algorithm can achieve up to 32% and up to 30% more recall than the PWH and GWHI algorithms, respectively. Also, it can achieve up to 38% and up to 34% more precision than PWH and GWHI, respectively Therefore, with our experiments, we are able to show that the proposed algorithm shows limited variation to changes in lighting.
Mdlti-View Video Generation from 2 Dimensional Video
Baek, Yun-Ki ; Choi, Mi-Nam ; Park, Se-Whan ; Yoo, Ji-Sang ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 53~61
In this paper, we propose an algorithm for generation of multi-view video from conventional 2 dimensional video. Color and motion information of an object are used for segmentation and from the segmented objects, multi-view video is generated. Especially, color information is used to extract the boundary of an object that is barely extracted by using motion information. To classify the homogeneous regions with color, luminance and chrominance components are used. A pixel-based motion estimation with a measurement window is also performed to obtain motion information. Then, we combine the results from motion estimation and color segmentation and consequently we obtain a depth information by assigning motion intensity value to each segmented region. Finally, we generate multi-view video by applying rotation transformation method to 2 dimensional input images and the obtained depth information in each object. The experimental results show that the proposed algorithm outperforms comparing with conventional conversion methods.
Wavelet based Blind Watermarking using Self-reference Method
Piao, Yong-Ri ; Kim, Seok-Tae ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 62~67
In this paper, wavelet based blind watermarking using self-reference method is proposed. First, we process wavelet transform of original image. Then, we set all domain except for the low-frequency domain to zero and make self-reference image after wavelet reverse transformation. By choosing specific domain according to the pixel value difference between original image and self-reference image, we make random sequence, use as watermark and embed. The experimental results of the watermark embedding and extraction on various images show that the proposed scheme not only has good image quality, but also has stability on JPEG lossy compression, filtering, sharpening, blurring and noise.
Error Concealment Based on Multiple Representation for Wireless Transmission of JPEG2000 Image
Ou, Yang ; Lee, Won-Young ; Yang, Tae-Uk ; Chee, Sung-Taek ; Rhee, Kyung-Hyune ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 68~78
The transmission of multimedia information over error-prone channels such as wireless networks has become an important area of research. In this paper, we propose two Error Concealment(EC) schemes for wireless transmission of JPEG2000 image. The Multiple Representation(MR) is employed as the preprocessing in our schemes, whereas the main error concealing operation is applied in wavelet domain at receiver side. The compressed code-stream of several subsampled versions of original image is transmitted over a single channel with random bit errors. In the decoder side, the correctly reconstructed wavelet coefficients are utilized to recover the corrupted coefficients in other sub-images. The recovery is carried out by proposed basic(MREC-BS) or enhanced(MREC-ES) methods, both of which can be simply implemented. Moreover, there is no iterative processing during error concealing, which results a big time saving. Also, the simulation results confirm the effectiveness and efficiency of our proposed schemes.
Modified Block Diagonalization Precoding with Greedy Approach
Kim, Sung-Tae ; Seo, Woo-Hyun ; Kwak, Kyung-Chul ; Hong, Dae-Sik ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 79~85
Dirty Paper Coding(DPC) can achieve the sum capacity of a multiuser multiple-input multiple-output(MU MIMO) broadcast channels. However, due to the high computational complexity of the successive encoding and decoding, deploying DPC in real systems is impractical. As one of practical alternatives to DPC, Block Diagonalization(BD) was researched. BD is an extension of the zero-forcing preceding technique that eliminates interuser interference(IUI) in downlink MIMO systems. Though BD has lower complexity than DPC, BD shows poor sum capacity performance. We show that sum capacity performance of BD is degraded due to no IUI constraint. Then, we modify BD to improve its sum capacity performance with relaxing the constraint and sub optimal channel set searching. With simulation results, it can be verified that our modification in BD induces some improvement in sum capacity performance.
A Tracking Scheme using Correlation Value at Advanced Offset Range in Galileo BOC(1,1) Signal
Yoo, Seung-Soo ; Kim, Sang-Hun ; Yoon, Seok-Ho ; Song, Iick-Ho ; Kim, Jun-Tae ; Kim, Sun-Yong ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 86~93
The Galileo system, a global navigation satellite system(GNSS) developed by E.U., uses the direct sequence/spread spectrum(DS/SS) modulation. A DS/SS-based system performs a fine synchronization between the received and locally generated spreading signals, via attacking process. In the absence of multipath signals, using the symmetric characteristic of the correlation function, the delay lock loop with the early minus late discriminator(EL-DLL) offers the best performance in tracking. However, in the presence of multipath signals, the symmetry of the correlation function could be lost, causing a tracking bias. In this paper, we observe that the correlation values in the advanced offset range remain almost unchanged, due to the multipath signals being received later than a line-of-sight signal. Based on this observation, we propose a novel tracking scheme for a Galileo BOC(1,1) system.
A Feed-forward Microsecond Level Real-time SOP Finding System
Jung, Hyun-Soo ; Shin, Seo-Yong ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 94~101
In this paper, we introduce a real-time state-of-polarization(SOP) finding system. The system divides the optical wave into linear horizontal- and vertical-SOP components and measures two different beat-signals, which are produced by superposition with reference optical source, in time domain. From these measured beat signals we can get SOP information of the signal instantly. Since the proposed scheme is a feed-forward measurement system, comparing with conventional systems which require an optical feedback loop, the measurement time becomes reduced tremendously. We also introduced a novel calibration method for compensating birefringence-related errors which may occur during the measurement. We prove the operation and performance of the proposed system through computer simulation and actual experiments.
Frequency Domain Turbo Equalization for Multicode DS-CDMA in Frequency Selective Fading Channel
Lee, Jun-Kyoung ; Lee, Taek-Ju ; Chae, Hyuk-Jin ; Kim, Dong-Ku ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 102~109
The higher data rate of mobile communications has been required for various multimedia services. In DS-CDMA system, one of the solutions to increase the throughput is to use multicode. However, multipath channel destorys the orthogonality of spreading codes, which causes the intercede interference(ICI). ICI gives severe effect on multicode DS-CDMA for BER performance. Conventionally, multicode DS-CDMA system uses the Rake receiver with turbo code, which cannot overcome error floor caused by ICI. In this paper, we propose frequency domain turbo equalization based on minimum mean squared error(FDTE-MMSE) for multicode DS-CDMA in frequency selective channel and evaluate its BER performance by computer simulation. The simulation results show that FDTE-MMSE gives much better performance in high Eb/N0 than the Rake receiver with turbo code in multipath length L>1.
Initialization of Cost Function for ML-Based DOA Estimation
Jo, Sang-Ho ; Lee, Joon-Ho ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 110~116
Maximum likelihood(ML) diretion-of-arrival(DOA) estimation is essentially optimization of multivariable nonlinear cost function. Since the final estimate is highly dependent on the initial estimate, an initialization is critical in nonlinear optimization. We propose a multi-dimensional(M-D) search scheme of uniform exhaustive search and improved exhaustive search. Improved exhaustive search is superior to uniform exhaustive search in terms of the computational complexity and the accuracy of the estimates.
Design of Unproved Diffie-Hellman Key Agreement Protocol Based on Distance Bounding for Peer-to-peer Wireless Networks
Park, Sern-Young ; Kim, Ju-Young ; Song, Hong-Yeop ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 117~123
We propose an improved Diffie-Hellman(DH) key agreement protocol over a radio link in peer-to-peer networks. The proposed protocol ensures a secure establishment of the shared key between two parties through distance bounding(DB). Proposed protocol is much improved in the sense that we now reduce the number of messages exchanged by two, the number of parameters maintained by four, and 2(7682(k/64)-64) of XOR operations, where k is the length of the random sequence used in the protocol. Also, it ensures a secure reusability of DH public parameters. Start after striking space key 2 times.
A Wavelet-Based Video Watermarking Approach Robust to Re-encoding
Yoo, Kil-Sang ; Lee, Won-Hyung ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 124~130
We present in this paper a method of digital watermarking for video data based on the discrete wavelet transform. In the proposed method, a watermark signal is inserted into the decompressed bitstream while detection is performed using the uncompressed video. This method allows detection if video has been manipulated or its format changed. We embed the watermark in the lowest frequency components of each frame in the un-coded video by using wavelet transform. The watermark can be extracted directly from the decoded video without access to the original video. Experimental results show that the proposed method gives the watermarked video of better quality and is robust against MPEG coding, down sampling and re-encoding to other type of video format such as MPEG4, H.264
Scalable Dual-Field Montgomery Multiplier Using Multi-Precision Carry Save Adder
Kim, Tae-Ho ; Hong, Chun-Pyo ; Kim, Chang-Hoon ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 131~139
This paper presents a scalable dual-field Montgomery multiplier based on a new multi-precision carry save adder(MP-CSA), which operates in both types of finite fields GF(p) and GF(
). The new MP-CSA consists of two carry save adders(CSA). Each CSA is composed of n = [w/b] carry propagation adders(CPA) for a modular multiplication with w-bit words, where b is the number of dual field adders(DFA) in a CPA. The proposed Montgomery multiplier has roughly the same timing complexity compared with the previous result, however, it has the advantage of reduced chip area requirements. In addition, the proposed circuit produces the exact modular multiplication result at the end of operation unlike the previous architecture. Furthermore, the proposed Montgomery multiplier has a high scalability in terms of w and m. Therefore, it can be used to multiplier over GF(p) and GF(
) for cryptographic applications.
A Low Complexity and A Low Latency Systolic Arrays for Multiplication in GF(
) Using An Optimal Normal Basis of Type II
Kwon, Soon-Hak ; Kwon, Yun-Ki ; Kim, Chang-Hoon ; Hong, Chun-Pyo ;
The Journal of Korean Institute of Communications and Information Sciences, volume 33, issue 1C, 2008, Pages 140~148
Using the self duality of an optimal normal basis(ONB) of type II, we present a bit parallel and bit serial systolic arrays over GF(
) which has a low hardware complexity and a low latency. We show that our multiplier has a latency m+1 and the basic cell of our circuit design needs 5 latches(flip-flops). Comparing with other arrays of the same kinds, we find that our array has significantly reduced latency and hardware complexity.