• Journal of Broadcast Engineering
• /
• v.17 no.6
• /
• pp.990-1003
• /
• 2012

In this paper, the possibility and necessity of the digital broadcasting propulsion in AM and FM is presented based on DRM and DRM+ transmission modes, They are the members of series technological family in digital radio development. As the frequency utilization, the application of DRM+ is flexible in any mode such as IN-BAND or OUT-OF-BAND. When the digital audio broadcasting is planned at LOW-VHF bandwidth such as TV channel No.5 and NO.6 being adjacent to FM band and OUT-Of-BAND DRM+ technology is applied, there is no collision and jamming. Particularly, in the IN-BAND Hybrid mode, it is mentioned that there was the difficulty problem for multiple SFN transmitters uses. Not like the IN-BAND mode the OUT-OF-BAND mode lets multiple transmitters, because neighbor transmitters do not interfere each other. Digital transmitter can be combined with the existing FM transmitter. The intensity of power and size of area can be easily determined according to local broadcasters' condition. And the OUT-OF-BAND mode is advantageous for AM/FM integration in digital radio receiver manufacturing, which makes the conversion schedule much shorter.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.837-840
• /
• 2007

We propose a novel digital driving method for AM-OLED (Active Matrix-Organic Light Emitting Diode) display. Proposed method modulates $V_{DD}$ so that luminance may be weighted in accordance with the bit significance. We can increase the minimum emission time or slower scan circuits are applicable by using proposed method.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.4 no.4
• /
• pp.264-271
• /
• 2011

ILS(Instrument Landing System) is the international standard system for approach and landing guidance. ILS was adopted by ICAO(International Civil Aviation Organization) in 1947 and is currently being used in commercial systems. To design the digital transmitter and receiver modules that can be mounted in the integrated ILS, we propose the digital design methods of digital double AM modulator and demodulator using FPGA chip, DDS(Direct Digital Synthesizer) for generation of sampling clock, demodulator of DDC(Digital Down Converter) structure, and spectrum analyzer using DSP chip. We demonstrate the efficiency of the proposed design method through experiments using developed transmitter and receiver modules. This system can be used as a high-performance commercial system.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2001.11b
• /
• pp.83-88
• /
• 2001

최근 ITU-R에서는 디지털 AM 라디오 방송과 관련하여 DRM(Digital Radio Mondiale)의 권고안을 채택하였다. 본 논문은 표준화된 DRM 방송 방식에 대하여 알아보고, 경쟁 관계에 있는 IBOC(In-Band On-Channel) DSB(Digital Sound Broadcasting) 방송 방식과 비교 분석하여 국내 디지털 AM 방송 방식의 결정과 실용화 전략 수립 과정에 도움이 되고자 한다.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
• /
• v.11 no.3
• /
• pp.45-55
• /
• 2000

DAB(Digital Audio Broadcasting)는 기존 아날로 그 방식 AM과 FM 라디오 방송의 한계와 문제점을 극복하고 CD 수준 음질의 오디오를 포함한 다양한 멀티미디어 서비스를 제공하는 차세대 라디오 방송이다. DAB는 전송 주파수 대역에 따라 기존의 FM/AM 대역과 다른 새로운 대역을 사용하는 Out-of-Band 방식과 기존의 FM/AM 대역을 사용하는 In-Band 방식으로 분류할 수 있다. Out-of-Band 방식으로는 유럽의 Eureka-147과 일본의 협대역 ISDB-T(Integrated Services Digital Broadcasting-Terrestrial) 방식이 있으며, In-Band 방식은 미국의 USADR(USA Digital Radio)사와 LDR(Lucent Digital Radio)사가 개발하고 있는 IBOC(In-Band On Channel) 방식과 국내 한국전자통신연구원(ETRI)에서 개발 중인 IBAC(In-Band Adjacent Channel) 방식이 있다. 본 고에서는 DAB의 전송 주파수 대역에 따른 방식별 특성을 고찰하고 유럽, 일본, 미국과 국내에서 상용화 서비스 또는 개발되고 있는 DAB 시스템의 기술동향을 분석 한다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.22 no.2
• /
• pp.220-227
• /
• 2011

With the rapid development of mobile communication technology, the technologies based on the diverse digital modulation schemes have been used for the frequency range of over 800 MHz. The only radiation immunity has been tested using only AM signal based on IEC 61000-4-3 without any consideration of the influence of electromagnetic radiation in Korea. However, it has not been tested by wideband digital modulation signals such as cdmaone(IS-95), WCDMA and PM signal. The purpose of this study was to review the standards. In addition, the input signals were analyzed and tested considering the environments in Korea. The results showed that the devices were influenced by digital modulation signal or PM signal more than by AM signal.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.133-136
• /
• 2007

IGZO TFTs were fabricated by conventional photolithography and wet-etching processes on metal substrates for the flexible display. The characteristics of TFTs on metal substrates were comparable to those of TFTs on glass substrates. Moreover, AM-OLED panels based on IGZO TFT arrays on metal substrates were successfully driven, for the first time.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.48 no.5
• /
• pp.643-649
• /
• 1999

In this paper, we proposed that ｉ) noise-tolerant four kinds of AM(Amplitude Modulation)-FM(Frequency Modulation) demodulators are designed, ⅱ) we derived undersampling frequency through the product via energy operator of the monocomponent AM-FM signals separated form two-component AM-FM signals, and ⅲ) these four kinds of AM-FM demodulators detect respectively information signals of the IA(Instantaneous Amplitude) and IF(Instantaneous Frequency) by undersampling frequency to be different each other from the undersampled monocomponet AM-FM signals. Particularly, the proposed algorithm can control undersampling frequency by an integer factor. And these efficient AM-FM demodulators are well worked with the undersampled AM-FM signals.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.6
• /
• pp.1061-1068
• /
• 2017

A RVDT is a sensor that measures angular displacement and the output signal of RVDT is a DSBSC-AM signal. For this reason, a DSBSC-AM demodulation processor is required to determine the angular displacement from the output signal. In this paper, DADC(Digital Angle to DC) which extracts the angular displacement from the output signal of a RVDT is implemented based-on modified Costas Loop usually used in the demodulation of DSBSC-AM signal by using FPGA. DADC can used with both 4-wire and 5-wire RVDTs and can exactly compensate the phase difference between the input excitation and output signals of a RVDT unlike the conventional analog RVDT signal conditioners which require external components. Since digital signal processing technique that can enhance the linearity is exploited, DADC shows 0.035% linearity error, which is smaller than 0.005% that of a conventional analog signal conditioner. The DADC are tested in an integrated experimental environment which includes a commercial RVDT sensor, ADC and an analog output block.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.1
• /
• pp.116-126
• /
• 1997

As the digital system with high sampling rates is required to process numerous data, it is difficult to realize the real time processing for this system. By using the nonlinear energy tracking signal operator, in this paper four kinds of AM/FM demodulators are proposed and designed by the undersampling scheme of decreasing the sampling rate. Particularly, the undersampling frequency and 3dB bandwidth are controllable of these systems and their conditions are respectively. Through the analysis of the designed detectors, useful results are obtained in respect to characteristics and errors.