• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.10
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• pp.921-932
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• 2016

In this paper, a modified FSA(Frequency Scaling Algorithm) is proposed for KOMPSAT-5 high-resolution SAR image generation. In order to enhance performance of azimuth compression, degraded in sub-aperture processing due to the imperfect geometric parameter of data acquisition, the full-aperture signal processing algorithm is designed based on the exact time-frequency analysis. In addition, an azimuth scaling function is newly devised to make the full-aperture processing algorithm suitable for KOMPSAT-5 sliding-spotlight mode. Different from the previous sub-aperture FSA schemes, the suggested technique could accommodate the merit of unified signal processing structure regardless of operational modes of KOMPSAT-5. Through the point target simulation, it is verified that the suggested algorithm provides superior performance of azimuth compression over the existing full-aperture processing methods. The experimental results using real data acquired by KOMPSAT-5 are also given to demonstrate the effectiveness of our scheme as well.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6C
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• pp.498-504
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• 2008

In this paper, an efficient hardware platform for the digital signal processing for OFDM Communication systems is presented. The hardware platform consists of a single FPGA, two DSPs with 8000 MIPS of maximum at 1 GHz clock, 2-channel ADC and DAC supporting maximum 125 MHz sampling rate, and flexible data bus architecture, so that a wide variety of baseband signal processing algorithms for practical OFDM communication systems may be implemented and tested. The IEEE 802.16 software modem is also presented in order to verify the effectiveness and usefulness of the designed platform.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.12
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• pp.1859-1867
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• 2021

Multi LiDAR sensors are being mounted on autonomous vehicles, and a system to multi LiDAR sensors data is required. When sensors data is transmitted or processed to the main processor, a huge amount of data causes a load on the transport network or data processing. In order to minimize the number of load overhead into LiDAR sensor processors, only semantic data is transmitted through data comparison between frames in LiDAR data. When data from 4 LiDAR sensors are processed in a static environment without moving objects and a dynamic environment in which a person moves within sensor's field of view, in a static experiment environment, the transmitted data reduced by 89.5% from 232,104 to 26,110 bytes. In dynamic environment, it was possible to reduce the transmitted data by 88.1% to 29,179 bytes.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.85-94
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• 2004

Loop detection systems have been used in real-time signal control system to collect traffic information for estimating queue lengths. The queue length algorithm uses speed as a key variable estimated from occupancy time and average vehicle length. The measurement of average vehicle length is affected from the lengths of feeder cable, but their effects have not yet been evaluated. In this study, the variability of average vehicle length due to the lengths of feeder cable is assessed through a field study, and a practical guidelines is proposed. By applying this result, the operational performance of real-time signal control system could be improved.

• Journal of the Institute of Convergence Signal Processing
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• v.23 no.2
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• pp.91-96
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• 2022

At the current camera-based technology level, sensor-based basic life pattern recognition technology has to suffer inconvenience to obtain accurate data, and commercial band products are difficult to collect accurate data, and cannot take into account the motive, cause, and psychological effect of behavior. the current situation. In this paper, radar technology for life pattern recognition is a technology that measures the distance, speed, and angle with an object by transmitting a waveform designed to detect nearby people or objects in daily life and processing the reflected received signal. It was designed to supplement issues such as privacy protection in the existing image-based service by applying it. For the implementation of the proposed system, based on TI IWR1642 chip, RF chipset control for 60GHz band millimeter wave FMCW transmission/reception, module development for distance/speed/angle detection, and technology including signal processing software were implemented. It is expected that analysis of individual life patterns will be possible by calculating self-management and behavior sequences by extracting personalized life patterns through quantitative analysis of life patterns as meta-analysis of living information in security and safe guards application.

• Journal of Advanced Navigation Technology
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• v.13 no.3
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• pp.311-318
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• 2009

This paper shows the research about the development of software receiving platform processing GPS/Galileo L1/E1/E5a signal. Various researches for new GNSS signal character are possible using software receiving platform by facile program code modification. In addition, the program that processes GPS and Galileo signal integration is expected to help developing integration of receiver algorithm that deal with new various GNSS signal. In this paper, it is introduced the structure of GPS/Galileo receiving platform using sampled IF data as a program input. The function of the software platform embodied using MATLAB tool is tested by live data from Galileo test satellites. The software platform is modulated according to their roll and function. Each module is able to use selective function on GNSS signal.

• Annual Conference of KIPS
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• 2001.04b
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• pp.751-754
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• 2001

열교환기(Heat Exchanger)는 원전 운영에 핵심적인 설비이다. 따라서 열교환기 전열관의 건전성 유무를 판단키 위해 정기적으로 비파괴검사의 일종인 와전류검사(ECT, Eddy Current Testing)를 수행하고 있다. 이러한 와전류검사 공정은 크게 3가지로 분류할 수 있다. 첫 번째는 전열관 상태검사를 위한 신호데이터 취득공정이고, 두 번째는 취득된 신호를 판독하여 전열관의 건전성 여부를 진단하는 평가공정, 마지막으로 평가공정에서 발생하는 방대한 데이터를 토대로 추이분석 자료를 제공할 수 있는 공정이 필요하다. 본 논문에서는 세 번째 공정에서 필요한 열교환기 Tubesheet를 사용자 정의에 따라 자동으로 구현할 수 있는 기능을 정의하고, 평가공정에서 발생한 데이터를 직접 Tubesheet상에 Mapping 처리하여 시각적으로 전열관 상태를 확인할 수 있는 프로그램 구현방법을 제시한다.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10a
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• pp.724-726
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• 1998

본 논문에서는 방대한 양의 데이터를 실시간으로 처리하기 위한 병렬 디지털 신호처리시스템을 제안한다. 버스와 메모리의 구조가 다른 네 가지 신호처리부 모델을 제안하고 그들의 성능을 분석한다. 신호처리부의 분석은 소나 알고리즘을 실행하는데 소요되는 하드웨어 지연시간과 버스 지연시간의 합을 척도로 한 성능 분석과 보드의 복잡도를 비교하는 방법을 통하여 이루어졌다. 성능분석한 결과, 지역 메모리와 공유 메모리를 함께 사용하는 모델이 가장 효율적인 것으로 나타났다.

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.501-504
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• 2000

근본적으로 방대한 양의 실시간 연산을 요구하는 영상 신호처리, 소나, 레이다와 같은 시스템에서는 시스템의 성능을 최대화하기 위해 병렬 신호처리 시스템의 사용이 불가피하다. 본 논문은 방대한 양의 데이터를 실시간으로 처리할수 있는 병렬 신호처리보드를 설계 및 구현하였다. 이 보드는 DSP칩간의 통신과 보드간의 통신이 가능하며, DSP칩이 마스터가 되어 EMIF(External Memory Interface Port)포트를 통해 다른 DSP칩의 지역메모리를 액세스 할수 있다. 또한 외부의 호스트 프로세서가 보드 내의 DSP칩에 프로그램을 다운로딩 할수 있다. 보드간의 통신은 PCI 버스를 통하여 이루어지며, DSP칩간의 통신과 DSP칩과 그의 지역메모리와의 통신은 지역버스를 통해 직접적으로 이루어진다. 보드에서 가장 핵심인 DSP-to-PCI제어기는 하드웨어 언어인 VHDL로 설계하였으며, 시뮬레이션 환경은 Synopsys ＆ ALTERA MaxplusⅡ를 사용하여 검증하였으며, 최종적으로 CPLD(Complex Programable Logic Device)칩을 사용하여 구현하였다.

• Journal of the Korea Society of Computer and Information
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• v.17 no.7
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• pp.97-106
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• 2012

Management of biosignal data in mobile devices causes many problems in real-time transmission of large volume of multimedia data or storage devices. Therefore, this research paper intends to suggest an m-Health system, a clinical data processing system using mobile in order to provide quick medical service. This system deployed health system on IP network, compounded outputs from many bio sensing in remote sites and performed integrated data processing electronically on various bio sensors. The m-health system measures and monitors various biosignals and sends them to data servers of remote hospitals. It is an Android-based mobile application which patients and their family and medical staff can use anywhere anytime. Medical staff access patient data from hospital data servers and provide feedback on medical diagnosis and prescription to patients or users. Video stream for patient monitoring uses a scalable transcoding technique to decides data size appropriate for network traffic and sends video stream, remarkably reducing loads of mobile systems and networks.