• Journal of the Korea Society of Computer and Information
• /
• v.15 no.8
• /
• pp.41-49
• /
• 2010

Digital broadcasting system has various affecting factors unlike analog broadcasting system, and has possibility of no signal reception in case of errors due to characteristics of digital system. And, digital broadcasting system has monitoring system for error occurrences handling various factors. ATSC mobile DTV system uses legacy frequency and provides mobile broadcasting services, and also requires monitoring systems for monitoring online broadcasting services and reporting to administrator about interference or influence with legacy systems, and error situations. In this paper, we propose efficient monitoring system which monitors online broadcasting status of ATSC mobile DTV, reports on poor signal reception, video streaming failures to administrator, and maintains reliable digital broad ca sting system.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.11
• /
• pp.2379-2384
• /
• 2010

The reception quality of broadcasting in car radio system may become poor due to the noise such as week signal strength, multipath, Adjacent Channel and so on. To improve this, some european nations and US. serve RDS(Radio Data System) on FM radio, AF(Alternative Frequency) and PI(Programme Identification) code contained information in RDS data are used to switch to the broadcasting having the best reception quality. There are many techniques and studies of maintaining the best reception quality. But many previous techniques are no longer the best way because RF chips are improved every year and noise components can be distinguished in detail. So this research will suggest the best switching technique to maintain the best reception quality.

• Journal of Broadcast Engineering
• /
• v.14 no.3
• /
• pp.311-321
• /
• 2009

In a single frequency network (SFN) for Advanced Television Systems Committee (ATSC) terrestrial digital television (DTV) system, the interference due to the use of same frequency among multiple transmitters or repeaters is inevitable for receivers. This problem can be solved by adjusting transmit power and time of each transmitter and repeater. To adjust SFNs, the ATSC recommended practice (RP) introduces a transmitter identification (TxID) signal which is embedded in a signal from each transmitter or repeater. This paper proposes an efficient method to estimate the individual reception power from each transmitter or repeater based on the channel profile of SFN and the total reception power. Moreover, field test results are provided to evaluate the performance of the proposed method.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.1B
• /
• pp.144-153
• /
• 2010

Flooding based routing protocols are usually used to disseminate information in wireless sensor networks. Those approaches, however, require message retransmissions to all nodes and induce huge collision rate and high energy consumption. In this paper, HoGoP (Hop based Gossiping Protocol) in which all nodes consider the number of hops from sink node to them, and decide own gossiping probabilities, is introduced. A node can decide its gossiping probability according to the required average reception percentage and the number of parent nodes which is counted with the difference between its hop and neighbors' ones. Therefore the decision of gossiping probability for network topology is adaptive and this approach achieves higher message reception percentage with low message retransmission than the flooding scheme. Through simulation, we compare the proposed protocol with some previous ones and evaluate its performance in terms of average reception percentage, average forwarding percentage, and forwarding efficiency. In addition, average reception percentage is analyzed according to the application requirement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.05a
• /
• pp.127-130
• /
• 2010

The reception quality of broadcasting in car radio system may become poor due to the noise such as week signal strength, multipath, Adjacent Channel and so on. To improve this, some european nations and U.S. serve RDS(Radio Data System) on FM radio. AF(Alternative Frequency) and PI(Programme Identification) code contained information in RDS data are used to switch to the broadcasting having the best reception quality. There are many techniques and studies of maintaining the best reception quality. But many previous techniques are no longer the best way because RF chips are improved every year and noise components can be distinguished in detail. So this research will suggest the best switching technique to maintain the best reception quality.

• International journal of advanced smart convergence
• /
• v.11 no.4
• /
• pp.41-46
• /
• 2022

This study is a Ku-band array antenna for the manufacture of low-orbit satellite communication terminals, designed to have miniaturization, high gain, and wide beam width. The transmission of low-orbit satellite communication has a right-rotating circularly polarized wave, and the reception has a left-rotating circularly polarized wave. The 4×8 array antenna was separated for transmission and reception, and it was combined with the RF circuit part of the transmitter and receiver, and was terminated in the form of a waveguide for RF signal impedance matching in the form of a transition from the microstrip line to the waveguide. The 30° beam width of the receiver maximum gain of 19 dBi and the 29° beam width of the transmitter maximum gain of 18 dBi are shown. Through this antenna configuration, the system was configured to suit the low-orbit satellite transmission/reception characteristics.

• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.9-11
• /
• 2008

In this paper, we describe a 1/4 rate robust modulation algorithm for Enhanced-xVSB system which is fully backward compatible with ATSC 8-VSB standard. Laboratory test results of proposed Enhanced-xVSB 1/4 rate mode is shown a significantly improved reception performance under multipath as well as AWGN channel. We suggest an Enhanced-xVSB terrestrial broadcasting system for in-band Pedestrian/Portable TV broadcasting service.

• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.183-184
• /
• 2008

From the beginning of a new millennium, the digital broadcasting services had been adopted to cable, satellite and radio broadcasting services as well as the terrestrial TV broadcasting services. The government established the installation standard of digital receiving equipment in 2007, which is needed for taking the new digital broadcasting services without additional facilities in an apartment house. In this paper, I will show the installation standard of digital receiving equipment in an apartment house and give a detailed explanation for the main criteria of it.

• Electronics and Telecommunications Trends
• /
• v.23 no.3
• /
• pp.130-137
• /
• 2008

최근 위성방송 기술은 고선명/고음질을 실현하고, 다양한 부가서비스를 제공하는 고품질의 디지털 전송방식으로 변화하고 있다. 이러한 위성방송의 수요확대에 다채널 데이터 전송 및 HD급 고품질의 영상을 전송할 수 있는 DVB-S2 시스템 개발에 한창이다. 본 논문에서는 DVB-S2 전송방식을 적용하기 위한 Ku-Ka 대역의 강우감쇠 등을 효과적으로 보상하여 보다 나은 위성방송 수신 가용도를 높이기 위한 방안에 대해 논한다.

• Proceedings of the IEEK Conference
• /
• 2003.11b
• /
• pp.251-254
• /
• 2003

DMB is a next-generation multimedia broadcasting system that not only enables digital broadcasting services such as transmission of CD-duality audio, traffic information, and real-time stock information, but also allows reception of high-quality digital TV in high-speed driving conditions. In the DMB system, MPEG-2 TS(Transport Stream) multiplex method and MPEG-4 System SL(Sync Layer) have been selected as the delivery layer. In this paper, an efficient interface scheme between an MPEG-2 TS processing hardware and software-implemented MPEG-4 system within a DMB terminal device is proposed.