• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.1
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• pp.55-59
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• 2004

전파의 특성을 측정하기 위해서 사용되는 디지털 주파수 측정기는 안테나를 통해서 수신기에 입력된 고주파 신호의 주파수를 측정하는 장치로써, 전파 정보 수집 장비의 중요한 구성품 중 하나이다. 이 분야는 고주파 기술이 발달된 미국이나 유럽에서 대부분의 장비를 개발해 왔으나 금번에 설계 제작된 주파수 측정기는 온도보상 등을 고려하여 정밀하게 설계제작 함으로써 수신 감도 -70㏈m에서 펄스폭이 l00㎱ 이상인 펄스 신호와 지속파(CW)신호의 주파수를 정확하게 측정하였다.

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.635-638
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• 2000

멀티미디어 기술의 총아라고 불리는 차세대 디지털 방송은 현재 선진 각 국에서 표준안 제정에 심혈을 기울이고 있으며 그 핵심적인 기술은 대부분 MPEG-2를 근간으로 하고 있는 실정으로 현재는 양방향 서비스에 대한 논의가 제한적으로 이루어지고 있다. 이에 차세대 영상압축 기술인 MPEG-4에서는 시스템 차원에서 사용자와의 상호작용을 지원할 수 있는 구조로 개발되어 있다. 본 논문에서는 이러한 기술적 차이에 착안해서 현재 제정된 디지털 방송 표준안을 기본으로 하고 사용자와의 상호작용을 지원하는 부가 데이터 방송은 MPEG-4 시스템 표준을 이용하여 양방향성이 강조된 디지털 방송 시스템 모델을 제안한다. 제안된 기술은 별도의 하드웨어의 지원 없이 소프트웨어만으로 처리할 수 있으며 차후 하드웨어로 제작될 디지털 TV 수신기모델을 손쉽게 검증, 제시함으로써 셋톱박스 및 디지털 TV 개발에 응용할 수 있다.

• The Magazine of the IEIE
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• v.29 no.7
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• pp.51-58
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• 2002

This paper describes functions required for implementation of digital television (DTV) broadcast receivers. The necessary functions for the DTV receiver vary with the transmission media-terrdstrial, cable and satellite. This paper briefly introduces its hardware and software structure, This paper also presents the future of DTV receivers according to the tomorrow's broadcast environment.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.338-338
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• 2004

• The Science & Technology
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• v.30 no.5 s.336
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• pp.28-29
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• 1997

노래방기기 모니터에 가사가 자막으로 처리되는 '영상자막 처리보드'를 국내 처음으로 개발한 (주)건인. 대당 3천만원씩 전량 일본에서 수입하던 이 제품을 대당 50만원씩 파격적인 가격으로 보급해 선풍을 일으킨 (주)건인은 올해 디지털 인공위성 수신기 자체개발로 제2의 변신을 시도하고있다.

• Journal of Broadcast Engineering
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• v.7 no.3
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• pp.211-218
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• 2002

This paper introduces the HD 3DTV camera and 3DTV receiver that are compatible with the ATSC HDTV broadcasting system. The developed 3DTV camera is based on stereoscopic techniques, and it has control function to control both left and right zoom lens simultaneously and to control the vergence. Moreover, in order to control the vergence manually and to eliminate the synchronization problem of the both images, the 3DTV camera has the 3DTV video multiplexing function to combine the left and right images into the single image. The developed 3DTV signal, and it has the various analog/digital interfaces. The performance of the developed system is confirmed by shooting the selected soccer game in 2002 FIFA KOREA/JAPANTM World Cup and by broadcasting the match. The HD 3DTV camera and receiver will be applied to the 3DTV industries such as 3D movie, 3D game, 3D image processing, 3DTV broadcasting system, and so on.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.37 no.6
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• pp.25-34
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• 2000

This paper describes design of a 250-Mbps 10-channel optical receiver array for parallel optical interconnection with the general-purpose CMOS technology The optical receiver is one of the most important building blocks to determine performance of the parallel optical interconnection system. The chip in CMOS technology makes it possible to implement the cost-effective system also. Each data channel consists of analog front-end including the integrated photo-detector and amplifier chain, digital block with D-FF and off-chip driver. In addition, the chip includes PLL (Phase-Lock Loop) for synchronous data recovery. The chip was fabricated in a 0.65-${\mu}{\textrm}{m}$ 2-poly, 2-metal CMOS technology. Power dissipation of each channel is 330㎽ for $\pm$2.5V supply.

• Journal of Broadcast Engineering
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• v.15 no.3
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• pp.414-425
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• 2010

When we implement the single frequency network (SFN) in ATSC terrestrial DTV system, there is an interference problem to DTV receivers due to the use of same frequency channel among transmitters and repeaters. To resolve this problem, it is recommended to adopt the transmitter identification signals in transmitting equipments. In this paper, we analyzed the influence suffered by legacy DTV receivers when the TxID signal is added to the DTV transmitting signals and the results were further verified by computer simulation, laboratory test and field test. The above tests show that if the TxID signal is added to the level of -30dB compared to the original DTV signal, the TOV(Threshold Of Visibility) increment in legacy receivers is about 0.17 dB. It means that we can insert and transmit the TxID signal in ATSC terrestrial DTV system without making the negative effect to the legacy DTV receivers.

• Journal of Digital Contents Society
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• v.1 no.1
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• pp.39-52
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• 2000

In this paper, we derive the BER performance of an asynchronous DS/CDMA system and analyze the improvement of BER performance through turbo coding and RAKE receiver in multipath Rayleigh fading and impulsive noise environments. As a result, impulsive noise affects the performance of the system more than multipath fading in lower $E_b/N_o$ than a certain threshold. However, in higher $E_b/N_o$, multipath fading are more dominant than impulsive noise. It is found that in lower $E_b/N_o$, turbo code improves the performance of the system against impulsive noise, and in higher $E_b/N_o$, RAKE receiver improves the performance of the system against multipath fading. Therefore, great improvement can be obtained by employing turbo code and RAKE receiver in multipath Rayleigh fading and impulsive noise environments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.8B
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• pp.1012-1020
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• 2011

In this paper a design of $\pi$/4-DQPSK baseband receiver for the exchange of digital data and e-mail between shore and ship stations and/or among ship stations in the maritime mobile service VHF channels is described. Due to the permitted relatively big frequency instability of local oscillators at the transmitter and the receiver of maritime communication system, the designed baseband receiver should have the capabilities of correct estimation and compensation of the synchronization parameters, such as symbol timing and frequency offset, from the received signal which might include relatively big frequency error. Simulated BER results show that the designed baseband receiver works less than 0.5dB loss under AWGN channel when the normalized frequency offset of the received signal is more then 20%.