• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.10
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• pp.39-46
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• 1999

In this paper, we propose new hardware architecture of a fast searcher for an initial code acquisition in wideband CDMA wireless local loop systems. The proposed searcher uses double-dwell serial search algorithm and has N active correlators for the high performance code acquisition. Since the N active correlators are designed with pipelined architecture, it is possible to reduce the hardware complexity with only one energy calculation. Our architecture is designed using VHDL to meet wideband CDMA wireless local loop standard and verified under JTC wideband channels. Average code acquisition time of the proposed fast searcher which has 16 correlators is about 40 seconds in case of initial installation and 0.16 seconds when a base station is known. The verified fast searcher is synthesized with in $0.6\mu\textrm{m}$ LG library. The synthesized searcher has 15.8K rates when the number of 4he correlators is 16.

• Journal of Advanced Navigation Technology
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• v.21 no.3
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• pp.258-263
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• 2017

This paper analyzed GNSS signal acquisition performance of a regional navigation receiver when an interference cancellation capability is applied. Intereference between the regional navigation and GNSS signal can be mitigated by the interference cancellation technique such as the successive interference cancellation (SIC) algorithm. However signal acquisition performance will be degraded when jamming-to-signal ratio (J/S) is large due to a cross-correlation properties of residual signals. In this paper we analyzed signal acquisition performance degradation due to the interference between the Kasami and GNSS Gold code signal. Monte Carlo simulation is used for the analysis and compared results with those of GNSS Gold code only condition.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.16 no.4
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• pp.12-19
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• 2008

GIOVE-B is the second experimental Galileo satellite for the Galileo In-Orbit Validation, which was launched by a Soyuz/Fregat rocket departing from the Baikonur cosmodrome in Kazakhstan on 27 April and now operated successfully. This paper presents the results obtained from processing of the E5a signal transmitted from the GIOVE-B. The acquisition and tracking of the data and pilot channels are performed by the E5a software receiver implemented by ETRI. Moreover, the paper suggests the GIOVE-B E5a-I/E5a-Q secondary code, which is determined by analyzing the correlation output of the primary correlator using the primary code.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.329-333
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• 2008

As construction projects become getting bigger and complicated, the importance of resource management in construction sites is to be emphasized all the more than ever, but the reality is now gone far away leaving data filing and management dependent on the hands of in-field managers, which gives rise to a variety of problems such as decreased productivity. The manually-dependent data management makes it hard to acquire data and information needed for projects both quickly and correctly with abundant cost and endeavor by accumulating the related data, and efficient project management, being exemplified by such practical applications as Bar-code, RFID(Radio Frequency Identification), GPS(Global Positioning System), PDA(Personal Digital Assistants), USN(Ubiquitous Sensor Network) and DAT(Data Acquisition Technology). In this context literature survey is made theoretically, taken into account 14 classification of construction works, 31 types of work classification in CIS, Masterformat as follows;

• Journal of Korea Multimedia Society
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• v.24 no.8
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• pp.1012-1019
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• 2021

Currently, since the black-white QR (Quick Response) codes have limited storage capacity, color QR codes have been actively being studied. By multiplexing 3 colors, the color QR codes can allow the code capacity to be increased by three times, however, the color multiplexing brings about the possibility of crosstalk and noises in the acquisition process of the final image, incurring the decrease of bit-recognition rate. In order to improve the bit recognition rate, while keeping the storage capacity high, this paper proposes a new type of color QR code which uses the pattern information as well as the color information, and then analyzes how to increase the bit recognition rate. For this aim, the paper presents an efficient system which extracts embedded information from color QR code and then, through practical experiments, it is shown that the proposed color QR codes improves the bit recognition rate and are useful for commercial applications, compared to the conventional color codes.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.1247-1250
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• 2005

이 논문은 multicarrier CDMA 이동 통신 시스템에서 직-병렬 혼합 pseudo-noise (PN) 코드 동기 획득 기술을 제안 했으며 다중경로 페이딩 채널에서 multiple access interference (MAI) 의 영향을 분석하였다. 직-병렬 혼합 동기 획득 방식은 입력되는 코드 위상의 불확정 영역 전체를 직렬 획득 방식과 병렬 획득 방식을 조합하여 탐색하는 방식이다. 이러한 방식은 완전 병렬획득보다 MAI의 환경에서 mean acquisition time (MAT)이 조금 늦어지지만 하드웨어의 구조를 훨씬 단순화 할 수 있다. 검파 및 오경보 확률을 closed-form 표현으로 mean acquisition time (MAT)를 유도하였다.

• Journal of information and communication convergence engineering
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• v.16 no.3
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• pp.153-159
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• 2018

In this paper, we present a three-dimensional (3D) optical encryption technique for quick response (QR) code using computational synthesized integral imaging, computational volumetric reconstruction, and double random phase encryption. Two-dimensional (2D) QR code has many advantages, such as enormous storage capacity and high reading speed. However, it does not protect primary information. Therefore, we present 3D optical encryption of QR code using double random phase encryption (DRPE) and an integral imaging technique for security enhancement. We divide 2D QR code into four parts with different depths. Then, 2D elemental images for each part of 2D QR code are generated by computer synthesized integral imaging. Generated 2D elemental images are encrypted using DRPE, and our method increases the level of security. To validate our method, we report simulations of 3D optical encryption of QR code. In addition, we calculated the peak side-lobe ratio (PSR) for performance evaluation.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.309-318
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• 2010

Simulation-based acquisition(SBA) is a new acquisition paradigm to deliver combat systems cheaper, faster, and better. ROK MND adopts the vision of SBA and is pushing ahead with dramatic reform. However, ROK MND does not develop the SBA architecture framework which facilitates the reuse of tools and techniques and data software code and algorithms among participants of collaborative environments. In this paper, we propose a conceptual Model of architecture framework for SBA. To do so, we analyse acquisition process of MND and propose the to-be operational view that describes fundamental concept for how Government, Industry, and Academia can collaborate and share information more effectively throughout the acquisition process. Furthermore, we identify the tools and techniques that supports the operational nodes, and propose technical view and all view, too. technical view compose of set of standards that can ensure interoperability among tools, techniques and data, and all view provide an overarching description of the architecture.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.230-230
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• 2006

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.587-587
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• 2006