• Journal of IKEEE
• /
• v.13 no.4
• /
• pp.116-124
• /
• 2009

Recently the CPU performance of modem chipsets or multimedia processors of mobile phone is as high as notebook PC. That is why mobile phone has been emerged as a leading ICON on the convergence of consumer electronics. The various applications of mobile phone such as DMB, digital camera, video telephony and internet full browsing are servicing to consumers. To meet all the demands the image quality has been increasingly important. Mobile phone is a portable device which is widely using in both the indoor and outside environments, so it is needed to be overcome to deteriorate image quality depending on environmental light source. Furthermore touch window is popular on the mobile display panel and it makes contrast loss because of low transmittance of ITO film. This paper presents the image enhancement algorithm to be embedded on image enhancement SoC. In contrast enhancement, we propose Clipped histogram stretching method to make it adaptive with the input images, while S-shape curve and gain/offset method for the static application And CIELCh color space is used to sunlight readability enhancement by controlling the lightness and chroma components which is depended on the sensing value of light sensor. Finally the performance of proposed algorithm is evaluated by using histogram, RGB pixel distribution, entropy and dynamic range of resultant images. We expect that the proposed algorithm is suitable for image enhancement of embedded SoC system which is applicable for the small-sized mobile display.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.16 no.5 s.96
• /
• pp.541-548
• /
• 2005

The research deals with the prediction and the measurement of electromagnetic wave propagation in rectangular shaped tunnels at f=2.65 GHz. The received power level was measured in the straight and the curved tunnel by using a spectrum analyzer and Satellite DMB mobile phone. Thus we have gotten the data for two cases, the straight and the curved tunnel whose radius is 300m. In addition, the prediction of wave propagation was conducted based on the ray-launching method, in same tunnel where measurement was performed. A good agreement of the measured and the predicted path loss could be confirmed. The measured path loss shows a marked difference in propagation loss: the path-loss exponent, 3.21, and 3.98, for a straight and a curved tunnel, respectively. The reason that path-loss exponent is high in a curved tunnel is that there is no direct wave but only the reflected waves, which attenuates rapidly with distance due to multiple reflections. Also the predicted path loss shows path loss exeponent, 3.2 and 3.95, for a straight and a curved tunnel which are similar to the simulation results.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.18 no.4
• /
• pp.473-479
• /
• 2008

With the advent of mobile phone, digital multimedia broadcasting(DMB) service is to be realized for multimedia data communication. For an acoustic part, a smaller and lighter microspeaker is also soon to be realized as an MP3 song player and a speakerphone. Sound quality in the microspeaker is becoming more important in mobile phones. It is evaluated by total harmonic distortion(THD). THD is the proportion of higher order frequencies output response to sinusoidal input signal. It is affected by uneven magnetic distribution and nonlinear response of diaphragm. In this paper, harmonic distortion is analyzed by considering magnetic and mechanical coupling effects. Simulated results of THD are compared with experimental data. Results show that THD in lower frequency range is higher due to high displace on voice coil and high mechanical response of high order frequency.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.04a
• /
• pp.236-241
• /
• 2008

With the advent of mobile phone, Digital multimedia broadcasting (DMB) service is to be realized for multimedia data communication. For an acoustic part, a smaller and lighter microspeaker is also soon to be realized as an MP3 song player and a speakerphone. Sound quality in the microspeaker is becoming more important in mobile phones. It is evaluated by total harmonic distortion (THD). THD is the proportion of higher order frequencies output response to sinusoidal input signal. It is affected by uneven magnetic distribution and nonlinear response of diaphragm. In this paper, harmonic distortion is analyzed by considering magnetic and mechanical coupling effects. Simulated results of THD are compared with experimental data. Results show that THD in lower frequency range is higher due to high displace on voice coil and high mechanical response of high order frequency.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2006.05a
• /
• pp.378-380
• /
• 2006

국내 휴대 단말기기(Mobile Phone, PDA 및 DMB 폰 등)의 하드웨어적 컨버젼스 기술은 국제 경쟁력을 충분히 확보하고 세계 시장에서 선두 역할을 수행하고 있으나, 휴대 단말기기에 필수적으로 구성되어지는 UI(User Interface)는 상대적으로 낙후된 실정이다. 이에 따라 3차원 그래픽 UI의 구현과 휴대 단말기기의 이벤트에 반응하는 3차원 아바타 시스템 개발을 통해 경쟁력 있는 소프트웨어적 컨버젼스 시대의 대비는 필수적이며, 본 논문에서는 휴대 단말기에서 3차원 UI의 구현 뿐 아니라 쉽고 빠르게 UI를 구축 할 수 있는 Authoring Tool 개발의 시급성을 인식하여 연구를 진행하고 있다.

• Journal of the Ergonomics Society of Korea
• /
• v.29 no.1
• /
• pp.55-59
• /
• 2010

Driver distraction is a major cause of traffic accidents in Korea. Various measures are being introduced to detect and warn driver distraction. The objective of this research is to investigate changes in driver's physiological signals due to distraction during driving. Driving simulator experiments have been carried out to investigate discrepancy in EEG signals among normal driving, DMB watching during driving, and cellular phone use during driving. Based on the discrepancy, combination of EEG signals have been identfied as candidate variables for detecting driver distraction. Statistical analysis has been carried out to verify their statistical significance.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.06a
• /
• pp.382-384
• /
• 2006

유비쿼터스 시대에 진입하면서 시장은 편의성과 휴대성을 점점 요구하고 한 장치에서 다양한 기능들을 수행할 수 있는 "all-in-one" 제품을 지향하고 있다. 특히 mp3player, 동영상 레이어 같은 멀티미디어요소는 모바일 디바이스에서 빠질 수 없는 기능이 되었다. 그러나 디바이스가 다양한 기능을 수행하게 될수록 내부의 하드웨어들은 더 많은 전원을 필요로 하고 있지만, 휴대성이 강조되는 모바일 디바이스에서 전지의 발전 속도가 모바일 디바이스에서 요구되는 전원모델을 충족시키지 못하고 있다. 따라서 전원 관리는 모바일 디바이스의 휴대 시간 증가를 위해서 매우 중요한 사항이 되었다. 본 논문에서는 임베디드환경의 모바일 멀티미디어 플랫폼에서 전력을 통합적으로 관리 할 수 있는 시스템 구현에 대해서 기술한다. 어플리케이션이 요구하는 전력공급 시스템을 설계하고, 이를 응용프로그램에서 제어할 수 있는 통합 소프트웨어인 디바이스 드라이버와 API를 설계하여 현재 산업계에서 요구하는 middle & high range 제품군(Smart Phone/PMP/DMB 등)에 최적화된 전력 관리 솔루션을 제공하고자 한다.

• Journal of Information Display
• /
• v.9 no.1
• /
• pp.6-13
• /
• 2008

Mobile phones use the embedded memory in LDI (LCD Driver IC). In memory accessing mode, data overlapping phenomenon can occur. These days, various contents such as DMB, Camera, Game are merged to phone. Accordingly, with more data transmission, there would be more data overlapping phenomenon in memory accessing mode. Human eyes perceive this data overlapping phenomenon as simply horizontal line noise. The cause of the data overlapping phenomenon was analysed in this paper. The data overlapping phenomenon can be changed by the speed of data transmission between the host and LDI. The optimum memory accessing position can be defined. This paper proposes a new algorithm for avoiding data overlapping.

• Electronics and Telecommunications Trends
• /
• v.21 no.2 s.98
• /
• pp.53-65
• /
• 2006

1990년대 말 본격화된 인터넷 서비스는 일반 개인들의 라이프스타일은 물론 정치, 경제, 사회, 문화적 측면에서 많은 변화를 야기시켰을 뿐만 아니라 텔레비전의 출현만큼이나 우리 생활양식을 크게 변화시켜 왔다. 나아가 통신망의 광대역화 및 방송의 디지털화에 따라 One phone, VoIP, WiBro, HSDPA, DMB, IPTV 등 유. 무선 통합, 음성. 데이터 통합 및 통신. 방송 융합이 발현되는 신규 서비스들이 속속 선보이면서 서비스, 사업자, 단말기 등이 융합되는 컨버전스 패러다임이 본격화되고 있는 양상이다. 이중 인터넷과 TV가 만나는 IPTV는 통신과 방송이라는 이종산업간의 대표적 융합서비스로서 VoIP, 초고속인터넷, TV 서비스를 동시에 제공하려는 통신사업자들의 TPS 사업전략의 일환으로 현재 전세계 280여 개 이상의 사업자에 의해 추진되고 있다. 이에최근 급부상하고 있는 IPTV 서비스에 관한 개념, 발전과정, 기술 배경, 국내. 외 사업자 추진 현황 및 향후 시장전망을 살펴봄으로써 IPTV 서비스의 발전가능성을 가늠해보고자 한다.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
• /
• v.8 no.2
• /
• pp.64-71
• /
• 2009

In this paper, This thesis is cell phone for make CAS service be for hand joining broadcasting Create a way CAS Chip. PerSam issue card inside use Seed Key and algorithm make CID Key and record CAS Chip. PerSam member Card inside use Seed Key and algorithm make Subscriber Key after include Subscriber. Key CAS Chip for record CID Key register EMM. make CAS CHIP in accordance with issue CAS Chip. broadcast service entry be for hand treatment so make low bandwidth for joining massage and make increase a member.