• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.391-394
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• 2006

The paper deals with the experimental GNSS receiver built at the Czech Technical University for experiments with the real GNSS signal. The receiver is based on software defined radio architecture. Receiver consists of the RF front end and a digital processor based on programmable logic. Receiver RF front end supports GPS L1, L2, L5, WAAS/EGNOS, GALILEO L1, E5A, E5B signals as well as GLONASS L1 and L2 signals. The digital processor is based on Field Programmable Gate Array (FPGA) which supports embedded processor. The receiver is used for various experiments with the GNSS signals like GPS L1/EGNOS receiver, GLONASS receiver and investigation of the EGNOS signal availability for a land mobile user. On the base of experimental GNSS receiver the GPS L1, L2, EGNOS receiver for railway application was designed. The experimental receiver is also used in GNSS monitoring station, which is independent monitoring facility providing also raw monitoring data of the GPS, EGNOS and Galileo systems via internet.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.487-489
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• 2005

This paper proposes a symbol timing recovery method that is simple in structure and can provide high speed symbol synchronization. Transmitter and receiver are not synchronized in communication systems using digital modulation. Receiver should search the timing variation of transmitter continuously. The proposed timing recovery method searches sample position by comparing previous sample value with next sample value. This method can be applied to digital and optical transceivers with high data rate.

• 한국군사과학기술학회지
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• 제11권4호
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• pp.36-45
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• 2008

LYNX ESM system operates digital receiver for analyzing radar of intrapulse modulation signal. This paper contains DC offset compensation method of IQ channels, imbalancing comensation method of amplitude and phase, precisional PW measurement using adaptive threshold set, analyzing algorithm of intrapulse modulation signals. Its effectiveness was proven by technical and operational test.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(1)
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• pp.69-72
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• 2000

This paper shows the more improved design of MRI receiver compared to conventional one based on Elscint Spectrometer. At first, the low-cost ADC is 16 bits, 3MHz sampling A/D converter Comparing to conventional one with signal bits of 14 bits, this device with those of 16 bits helps getting Improved the image resolution improved. If frequency is designed centering around 7.6 MHz to be satisfied in 10 MHz of maximum input bandwidth of ADC. For 1st demodulation, fixed IF is used for the purpose of the implementing multi nuclei system. Control parts & partial digital parts are integrated on one chip(FPGA). In DDC(Digital Down Converter), we got required bandwidth of LPF by controlling its decimation rate. With above considerations, we designed optimal receiver for high resolution imaging to be implemented through PC interface & experimental test of receiver of MRI after receiver's fabrication.

• The Journal of the Acoustical Society of Korea
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• 제23권3E호
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• pp.74-78
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• 2004

As analog audio systems are changing to digital systems, the DAB (Digital Audio Broadcasting) is expected to provide CD quality audio, various data services with interactiveness and excellent mobile reception ability. The DMB (Digital Multimedia Broadcasting), as more advanced successor of the DAB, adds video capability on the audio and data services. The DAB system assures high quality audio services even when the reception is through portable and mobile receivers. In this paper, USB-DAB receiver and PCI-DMB receiver are designed and implemented. The DAB receiver and the DMB receiver incorporate with PC to make use of computational power and application software of Pc. This enables the developed system to be more flexible and to meet various applications easier.

• 디지털산업정보학회논문지
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• 제8권1호
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• pp.117-123
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• 2012

This paper implements mobile Worldwide Interoperability for Microwave Access (WiMAX) receiver using Software Defined Radio (SDR) technology. SDR system is difficult to implement on the mobile handset because of restrictions that are computing power and under space constraints. The implemented receiver processes mobile WiMAX software modem on Open Multimedia Application Platform (OMAP) System on Chip (SoC) and Field Programmable Gate Array (FPGA). OMAP SoC is composed of ARM processor and Digital Signal Processor (DSP). ARM processor supports Single Instruction Multiple Data (SIMD) instruction which could operate on a vector of data with a single instruction and DSP is powerful image and video accelerators. For this reason, we suggest the possibility of SDR technology in the mobile handset. In order to verify the performance of the mobile WiMAX receiver, we measure the software modem runtime respectively. The experimental results show that the proposed receiver is able to do real-time signal processing.

• 대한임베디드공학회논문지
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• 제3권4호
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• pp.235-243
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• 2008

In this paper, a software-based Digital Radio Modiale(DRM) receiver is implemented on a Digital Signal Processor(DSP). DRM stands for the European radio broadcasting standard to bring AM radio into digital radio, designed to work at frequencies below 30MHz. DRM can offer various data services such as text messaging and slideshow services as well as audio services. The DRM receiver implemented on the Tensilica DSP core performs well at low signal strength indication of -102dBm.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.198-202
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• 2003

An engineer prefers DIFM receiver which is superior to instantaneous response rather than superheterodyne receiver which has a scan rate in normal wide band receiver designing. But DIFM receiver has weak point in sensitivity and continuous wave signal because of special environments. In this paper we propose the method which is certificated through simulation and prototype testing to improve sensitivity of DIFM receiver. And we analyze the important factors of DIFM receiver from our results.

• 전자공학회논문지
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• 제54권1호
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• pp.139-146
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• 2017

ISDB-T(Integrated Service Digital Broadcasting Terrestrial)는 OFDM(Orthogonal Frequency Division Multiplexing) 기반의 전송기술 및 Time Interleaving 기술을 사용하고 있기 때문에 다중 경로 및 Impulse Noise에 대응 가능하며, 이동 수신 환경에서도 어느 정도 양호한 성능을 나타낸다. 원세그(One-Seg), 풀세그(Full-Seg)는 할당된 세그먼트 개수에 따라 구분하며, 원세그 수신기는 변복조 방법으로 QPSK(Quadrature Phase Shift Keying)를 사용하기 때문에 64QAM(64 Quadrature Amplitude Modulation)을 사용하는 풀세그 수신기와 비교하여 높은 기술력 없이도 구현 가능하지만, 영상 데이터율의 한계로 화면 사이즈와 해상도의 제한이 크다. 본 논문에서는 셋탑박스, 고정형 TV, 일체형 네비게이션 등에 적용 가능한 HD급 해상도를 지원하는 풀세그 ISDB-T 방송 수신 모듈을 설계하고 구현한다. 실험을 통해 개발된 풀세그 ISDB-T 방송 수신 모듈의 기능이 정상적으로 동작함을 확인하였다.

• 한국군사과학기술학회지
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• 제9권3호
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• pp.116-122
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• 2006

A fast scan digital-IF FFT receiver at the radio communication band is presented for spectrum monitoring applications. It is composed of three parts: RF front-end, fast LO board, and signal processing board. It has about 19GHz/s scan rate, multi frequency resolution from 10kHz to 2.5kHz, and high sensitivity of below -99dBm. The design and performance analysis of the digital-IF FFT receiver are presented.