• Journal of electromagnetic engineering and science
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• v.15 no.4
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• pp.250-257
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• 2015

This paper presents an experimental measurement system for 3-6 GHz microwave tomography (MT) of the breast. The measurement system is constructed as a minimal test bed to verify key components such as the sensing antennas, radio frequency (RF) transceiver, sensing mechanism, and image reconstruction method for our advanced MT system detecting breast cancer at an early stage. The test bed has eight RF channels operating at 3 to 6 GHz for high spatial resolution and a two-axis scanning mechanism for three-dimensional measurement. The measurement results from the test bed are shown and discussed.

• Electronics and Telecommunications Trends
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• v.24 no.3
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• pp.91-102
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• 2009

FCC(Federal Communications Commission 미국 연방통신위원회)는 2008년 11월 스펙트럼 사용 효율을 높이고 새로운 서비스 도입을 용이하게 하기 위해 TV White Spaces를 대상으로 주파수 공유 기술인 Cognitive Radio 기술을 적용하기로 하고 관련 규정을 개정하였다. FCC는 TV White Spaces에서 고정 서비스와 개인/휴대서비스기기 사용을 허용하기로 방침을 정하고 2009년 5월 12일 DTV 전환 완료 이후 관련 기기 사용을 허용하기로 하였다. 본 논문에서는 FCC의 법규 개정 현황과 함께 이를 기술적으로 뒷받침하기 위한 IEEE 802.22, TV White Spaces ECSG, ECMA에서의 표준화 동향을 설명하고, 핵심 기술로서 스펙트럼 센싱 기술, 무선자원관리 기술, PHY/MAC 관련 기술 개발 동향에 대해 요약 기술하였다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.8
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• pp.828-837
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• 2014

With the rapid development of radio technologies, there have been actively researching the convergence between radio technology and other industry as well as wireless communications itself. In this paper, we investigate the paradigm shift of radio policy as radio technologies such as small cells and cognitive radio advance, and analyze the directions of spectrum policy and radio technology to promote the creative use of radio waves. In particular, we propose the spectrum policy for the expansion of open spectrum policy, technology development of interference management, and restructuring of the Korean radio law.

• Journal of radiological science and technology
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• v.6 no.1
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• pp.69-80
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• 1983

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.4
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• pp.442-450
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• 2014

This paper is a study of the propagation characteristic of matching liquids in the skin-covered breast model. In order to evaluate the matching liquids, we investigated six kinds of matching liquids applied to proposed 1-D breast model from frequency range of 3~6 GHz. A uniform plane wave is projected / transmitted inside the multi-layered breast model. Then the propagation characteristics inside the model and the transmission loss of each matching liquids were analyzed. The studying method presented in the paper can be used in the breast cancer detection system, the field of cancer detection using human tissue and the field of other medical devices. This paper was applied to the breast cancer detection system. Consequently, these studies could be used to determine the suitable type of matching liquids for breast cancer detection system and to apply useful for performance analysis.

• Electronics and Telecommunications Trends
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• v.35 no.5
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• pp.69-82
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• 2020

In many technologies, artificial intelligence (AI) is becoming an important topic for areas based on the field of big data. However, applied AI cases and the research status of radio wave technology are not widely known to the public. The spread of AI to other areas is being followed by radio wave technologies, and much effort is being taken to evolve it into intelligent radio wave technologies in the future. This paper presents the recent areas of interest in radio wave technology, such as spectral sharing, illegal spectrum monitoring, radar detection, radio wave medical imaging, and channel modeling; examines the requirements for applying AI; and describes the applied cases, research trends, and standardization efforts that apply AI technology to them. On this basis, we will discuss the prospects of AI application to the expected radio wave technology of the future.

• Korean Journal of Digital Imaging in Medicine
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• v.6 no.1
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• pp.41-49
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• 2003

• Journal of radiological science and technology
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• v.13 no.2
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• pp.1-14
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• 1990

As the institute of education teaching radiologic technology in Korea, different from others, junior college is the only institute which has been managed for it as a two-year educational course for 27 years since 1963 when it was established for the first time in our country irrespective of the needs of the times. But according to the development of medical equipment, variety of medical skill, increase of medical demands now a days, the supply of radiologic technology in modern medicine not only makes it advance as an inevitable factor but also broadens the area of its business systematically. Therefore, we got the following results after we had considered the necessity to lengthen the term of education and searched for the most reasonable way. 1. The term of study of the radiologic technologists in junior college must be lengthened to 3 years from 2 or 3 years regulated in the law of education. 2. In three-year curriculum, the subjects like basic medical science, science and engineering and ultramodern science, etc., which are lated to the new radiologic science must be taught in the junior colleges, and hospital practice also must be a compulsory subject in curriculum. 3. As the school years becomes longer, a lot of programs to make the study effective must be searched, researched and propelled forward.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.110-115
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• 2000

A K-band GaAs MMIC receiver module has been developed using 0.15 ${\mu}{\textrm}{m}$ HEMT technology process. It incorporates two front end low noise amplifiers, a double balanced diode mixer, and filters. The RF input frequency ranges 20.1 to 21 GHz and the IF output 1.1 to 2 GHz. Test results show an overall conversion gain of more than 27 dB, and less than a 2.2 dB noise figure. The image-rejection ratio greater than 21 dB has been obtained. The isolation between RF and IF ports is better than 27 dB, and between LO and IF is more than 50 dB.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.11b
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• pp.77-79
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• 1999

In this paper, designed scheme and the performance results of implemented Grand alliance DTV RF up-converter are described. It can generate all channel band (ch.2-ch.60) of Korean broadcasting channel band. The experiment result shows the implemented RF up-converter satisfy the ATSC standards.