• Journal of the Institute of Convergence Signal Processing
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• v.7 no.4
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• pp.184-188
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• 2006

This paper presents DSP based narrow band satellite communication signal power detector for tracking control of mobile satellite antenna system. An analog filter based conventional power detector has poor performance due to frequency drift of carrier. Also, it is very difficult to change an analog filter bandwidth according to changed bandwidth of transmitted signal. To solve these difficulties, we proposed DSP based signal power detector, which is easy to change bandwidth of filter and to match shifted frequency of carrier. The proposed signal power detector consists of a FFT function to measure frequency drift of carrier, a programmable filter bank function to limit of received signal bandwidth and a power calculation function to measure power of filtered signal in 12-bit linear scale. Test results of implemented signal power detector, based on TMS320C5402 DSP, showed that it satisfied required functions and performances and properly operated.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2803-2805
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• 2002

멀티미디어의 표준화에 대한 관심이 컴퓨터, 방송, 통신 등의 분야에서 더욱 높아지고 있다. JPEG2000 표준안은 영상 부호화에 따른 새로운 형태의 영상압축 뿐만 아니라 높은 성능에 부응하고자 하는 것으로 기존의 표준안보다 왜곡율과 특정부분의 영상품질을 한 차원 상승시킬 수 있어서 효율적인 면에서 더욱 우수하다. 영상의 손실 및 무손실 압축, 대용량 영상압축, 그리고 화소의 정밀도와 해상도의 차이에 의한 점진적 전송이나 관심영역의 지정과 처리 등이 그 특징특이다 JPEG2000 표준안은 인터넷, 컬러 팩시밀리, 인쇄, 스캐닝, 디지털 사진, 원격 감지, 휴대기기 등과 의료 영상 디지털 도서관, 전자 상거래 등에 다양하게 응용할 수 있다. 본 논문은 JPEG2000 표준안의 최신동향과 전반적인 기술내역에 대하여 설명하고 영상압축 효율과 화질, 그리고 처리 속도 등을 기존 알고리즘과 비교하여 그 기술적 특징을 실험을 통하여 비교 제시한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.05a
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• pp.806-808
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• 2013

야간에 항로를 알려주는 등명기는 항상 점등 되어 있어야 한다. 따라서 중요한 장소에는 주 등명기 뿐만 아니라 예비 등명기를 추가 설치 운영해야한다. 이는 추가적인 경제적 비용 및 설치공간부족 등 많은 제약조건이 따르게 된다. 하지만 연구 중인 예비기능을 구비한 등명기가 개발되면 이러한 문제점을 해결할 수 있다. 본 논문에서는 예비기능을 구비한 등명기와 통신을 하기 위한 프로토콜을 제안한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.7
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• pp.1543-1551
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• 2011

Dithering scheme has been widely used to improve the resolution of DCO(Digitally Controlled Oscillator) in conventional ADPLLs(All Digital Phase Locked Loop). In this paper a new resolution improvement scheme is proposed where a simple DAC(Digital-to-Analog Converter) is employed to overcome the problems of dithering scheme. The frequencies are controled by varactors in coarse, fine, and DAC bank. The DAC bank consists of an inversion mode NMOS varactor. The other varactor banks consist of PMOS varactors. Each varactor bank is controlled by 8bit digital signal. The proposed DCO has been designed in a $0.13{\mu}m$ CMOS process. Measurement results shows that the designed DCO oscillates in 2.8GHz~3.5GHz and has a frequency tuning range of 660MHz and a resolution of 73Hz at 2.8GHz band. The designed DCO exhibits a phase noise of -119dBc/Hz at lMHz frequency offset. The DCO core consumes 4.2mA from l.2V supply. The chip area is $1.3mm{\times}1.3mm$ including pads.

• Journal of Satellite, Information and Communications
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• v.11 no.2
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• pp.23-28
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• 2016

In this paper, we proposed the novel algorithm which controls the resolution of the HDMI(High Definition Multimedia Interface) by the channel estimation from WiFi-AP(Access Point) in the ISM(Industry-Science-Medical) band. The 2.4 and 5 GHz channel models are widely used since they have identical RF property as RSSI(Received Signal Strength Indication). Especially, the performance degradation of signal-transmission and streaming of WiFi will be occurred by the co-channel interference between AP(Access Point) and increased number of smart devices. Therefore, the optimization scheme of video format timing was designed by HDMI-CEC(Consumer Electronics Control) which considers the transmission speed of radio channel. The HDMI resolution, video quality of home-gateway and digital TV and the decision of PIP position can be maintained by the protocols between smart devices and DLNA(Digital Living Network Alliance) via proposed technique.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.7
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• pp.1289-1295
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• 2007

In this paper, we implemented high-performance concurrent control system which manages whole RF systems with digital type and communicates with remote station on both wire and wireless networking. It consists of FPGA (Field Programmable Gate Array) part which controls forward/reverse LPA (Linear Power Amplifier), forward/reverse LNA (Low Noise Amplifier), channel cut wire/wireless TCP/IP, etc, master microprocessor (AVR), which manages the whole control system, Slave microprocessor which communicates SA (Spectrum Analyzer) and observes frequency spectrum of each channel with the resolution of 5KHz, 10 channel card microprocessor which independently observes each channel card and sets frequency synthesizer in channel cut and other peripherals and logics. The whole system is divided to two parts of H/W (hardware) and S/W (software) considering operational efficiency and concurrency, and implementation and cost. H/W consists of FPGA and microprocessor. We expected the optimized operation through H/W and SW co-design and hybrid H/W architecture.

• The Journal of the Acoustical Society of Korea
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• v.38 no.4
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• pp.371-377
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• 2019

In this paper, we present the sea trial results of long distance underwater acoustic communication in the East Sea, October 2018. One transmitter and sixteen vertical array receivers were used to collect underwater acoustic communication signals, and the maximum distance between the transmitter and the receiver was 90 km. Information was transmitted by BFSK (Binary Frequency Shift Keying) and BCSK (Binary Chirp Shift Keying) method, which are typical digital frequency modulation techniques. Experimental results show that there is no error in all cases at the transmission distance of 60 km, and BFSK and BCSK have average uncoded bit error rate of 0.0197 and 0.0007 respectively without channel coding at 90 km transmission distance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1202-1210
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• 2005

For the efficient and safe navigation management of ships cruising across oceans, international maritime law environments have been reinforced and the demand of information sharing between ships and shore has also been increasing. According to these environments and demand. researches about digital ships, ship integration, and ship integration networks have been active recently in US and Europe. In this raper, we first investigate about the proper ship integration platform, and then design and implement a ship integration network based upon the ship integration platform. We construct networks connecting various devices and systems into a layered architecture, and design an integration protocols. Based upon this architecture and protocols, we implement an ship integration system which manages all data and information of ship in a standardized platform and support ship-shore information sharing through which the more efficient and safer ship navigation management are supported with help from shore. We test our ship integration system by applying it to real operating ships and we find our system reliability and verify the efficiency of ship-shore information sharing and management.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.431-436
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• 2003

It's about time we had to think an alternative to recover out insufficient fishery market caused by IMF locally as well as the fishery agreement on Japan and China. The Ministry of Maritime Affairs ＆ Fisheries have planning the advancing fishery information integrated system for the fishing present condition, marine resource administration and applicability consideration. The fishery information communication system is build up to the raw data ＆ process-network-content. The communication system must be small size, low cost and adapted SSB transceiver, that is using fishery shipping. In this paper We present digital data communication network to exchange information for fishery and safety between fishing ship and coast station in cheeper communication fee using SSB(single Side Band) in HF(High Frequency) band.

• Electronics and Telecommunications Trends
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• v.31 no.1
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• pp.111-120
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• 2016

최근 디스플레이 기기의 해상도에 대한 관심이 높아지면서 고화질용 멀티미디어 인터페이스의 중요성이 부각되고 있다. 화질 저하를 막기 위해 과거의 아날로그 인터페이스에서 디지털 인터페이스로 변화되었고, 이후 포트의 크기 축소와 음성지원의 필요성이 대두됨에 따라 고화질 멀티미디어 인터페이스(High-Definition Multimedia Interface: HDMI) 기술이 개발되었다. 2002년에 HDMI 규격이 발표된 이후, PC, DVD 플레이어, TV 등 다양한 멀티미디어 기기에서 그 사용이 꾸준히 증가되고 있다. 또한, HDMI 케이블의 전송거리 제한을 극복하기 위한 노력의 일환으로 최근 수백 meter에서 수십 km까지 전송이 가능한 광 HDMI 기술이 개발되어 그 활용도가 높아지고 있다. 본고에서는 HDMI의 기술동향을 살펴보고 최근 개발된 광 HDMI 기술의 개발현황을 소개하고자 한다.