• Journal of Advanced Navigation Technology
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• v.3 no.1
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• pp.52-59
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• 1999

Digital microwave wideband receiver including linear amplifier, analog-to-digital converter(ADC) and digital signal processor is able to analyze its performance using sensitivity and dynamic range of system. Determination of gain, third-order intermodulation products and ADC characteristics and design criteria for the linear amplifier chain is essential problem for sensitive and dynamic range. Also, if there are two signals with frequencies very close, digital signal processor must be able to separate the two signals. In this paper, we measured dynamic range as gain was changed and determined gain value for the proper sensitivity and dynamic range and high resolution spectrum estimation was used to separate two close signals.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.879-885
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• 2004

This paper describes an adaptive signal processing of digital receiver with digital down convertor(DDC). DDC is composed of numerically controlled oscillator(NCO) and digital low pass filler and the received signal is processed by numerical algorithm. The simulation results of digital receiver using the passband sampling technique are presented and we confirmed that the received low IF signal is converted to zero IF by numerically processed DDC. Direction of arrival(DOA) estimation technique using multiple signal classification(MUSIC) algorithm with high resolution is also discussed. We knew that an accurate resolution of DOA depends on the input sampling numbers and antenna element numbers.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.11b
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• pp.71-75
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• 1999

본 논문은 한국형 디지털 TV 방송 규격/sup [1]/을 따르는 디지털 지상파 방송 신호를 수신할 수 있는 DTV 수신기의 구조에 관한 것이다. 국내 방송은 99년 10월 실험 방송이 시작될 예정이며 현재 제한된 지역에서 일부 방송을 하고 있는 상태다. 본 셋트는 8 VSB로 전송되는 디지털 방송신호를 수신할 수 있으며, ATSC 표준/sup [2]/에서 규정한 18가지 영상 포맷을 디코딩하여 화면에 디스플레이 할 수 있다. 특히 고화질 변환기능을 채용해 디지털 방송 활성화 이전에도 아날로그 TV방송, DVD, VCR 등 프로그램을 고화질로 즐길 수 있다. 또한 본 시스템을 구현하기 위해 자사가 개발한 DTV용 칩 셋을 사용하였다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.2111_2112
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• 2009

본 연구는 화재감시용 R형 중계기와 수신기에 일반방송 및 비상방송기능을 추가하여 이를 통합적으로 운영할 수 있도록 한 것이다. 이를 위해 소방용 중계기에 구역별로 스피커를 제어할 수 있는 기능을 부가하고, 화재수신기에는 디지털방식의 초소형으로 제작된 방송앰프를 내장하여 제작하였다. 제작된 시스템은 기존의 방식과 비교하여 장비의 설치공간을 감소시킴과 동시에 간선공사비용을 최소화하여 경제적인 시공이 가능한 것을 확인하였다.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.4
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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.

• Information and Communications Magazine
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• v.13 no.7
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• pp.40-50
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• 1996

본고에서는 디지털 DBS 방송시스템 기술을 설명하는데 있어 먼저 국제적 추세를 논하고 나서 무궁화호 위성을 위한 디지털 위성방송 시스템에 관한 구조를 송신국, RSMS 및 수신기로 나누어 논한 뒤 디지털 DBS 방송시스템 기술에 대해서는 비디오 기술, 오디오 기술, 데이터 기술, 변조 및 채널 부호기술 및 링크 분석을 중심으로 설명하였으며 마지막으로 디지털 DBS 방송시스템 기술을 향상시키기 위한 방안에 대해서 논하였다.

• Journal of Korea Multimedia Society
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• v.15 no.3
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• pp.364-371
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• 2012

Currently, CMMB(China Mobile Multimedia Broadcasting) and the conventional analog TV broadcasting have transmitted by using UHF(Ultra High Frequency : 474MHz~754MHz) band. Normally, the transmission power of the digital TV broadcasting is lower than the conventional analog TV broadcasting to protect the reception quality of the conventional analog TV broadcasting. The reception sensitivity of CMMB receiver has severely deteriorated due to adjacent the conventional analog TV broadcasting signals which called ACI (Adjacent Channel Interference). To improve the reception sensitivity of a CMMB receiver on ACI environment, this paper proposed a simple method which is tuning a cut off frequency of LPF (Low Pass Filter). From the experiment, the reception sensitivity of CMMB receiver was improved as 11.3dB.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.3
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• pp.282-288
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• 2014

In this paper, we have analyzed and designed a digital RF receiver based on the optimization of the dynamic range parameter to secure the wideband characteristics and linearity of digital radar receivers. To improve the wideband characteristics and dynamic range, a low noise amplifier is matching design with a noise source to minimize the noise figure in 1 GHz bandwidth and we improved the linearity of RF-receiver by securing the conversion gain characteristics of receiver through the design of active mixer. RF receiver is designed to give gain 63 dB, noise figure 1.2 dB and dynamic range of RF receiver has 75.8 dB in a wide band of 8.8~9.8 GHz. It is shown to be applicable to X-band digital radar receiver.

• Broadcasting and Media Magazine
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• v.8 no.1
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• pp.78-85
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• 2003

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.5
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• pp.568-573
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• 2019

Modern Radars are evolving into MFRs which can search multiple targets simultaneously and then track them. Additionally they should be able to avoid some external jamming signals. Applying to these MFRs, Antennas should be able to perform DBF including to not only real-time beam steering but also multi-beam forming simultaneously. And they can cancel the beam at the specific direction. In this paper, we describe the implementation of sub-array type antenna hardware which can be applying DBF. Also we propose the modified amplitude aperture distribution for suppressing the side lobe level and explain the sub-array receiver design with amplitude tapering. It consists in making the amplitude weighting in 2 steps. In order to compare two weighting cases, we investigate the G/T performance for the array antenna. At the conclusion, we make a comparative study for the dynamic range of every sub-array receiver and present the hardware implementation that is more advantageous for sub-array alignment and calibration in DBF.