Kyu-Tae Yang

Development of terrestrial DMB transmission system based on Eureka-147 DAB system

This paper introduces T-DMB transmission system in Korea based on Eureka-147 DAB and presents a new architecture of transmission system for digital multimedia services. For transmission of the digital multimedia contents in mobile environment by using the existing DAB, we developed a T-DMB processor which performs T-DMB encoding and insertion of the media stream into the existing DAB transmission system. After the implemented T-DMB processor can be connected to the front of the commercial Eureka-J47 DAB system, and the performance of the T-DMB system is confirmed through the T-DMB experimental broadcasting in Korea.

System and Services of Terrestrial Digital Multimedia Broadcasting (T-DMB)

Commercial terrestrial digital multimedia broadcasting (T-DMB) service was launched on December 1st, 2005, in the Seoul metropolitan area of the Republic of Korea. As the worlds first commercial terrestrial mobile multimedia broadcasting service, T-DMB garnered huge attention in the field of mobile broadcasting. This paper presents the history, system, and services of T-DMB

Study on the Performance of Hierarchical Modulation for AT-DMB System

This paper introduces an Advanced Terrestrial DMB (AT-DMB) system which provides higher efficiency of transmission and better quality of service than conventional T-DMB system. In AT-DMB, a hierarchical modulation method is applied to transmit more data while maintaining backward compatibility to conventional T-DMB receivers. This method can provide not only high quality video service but also lots of broadcasting channels. In this paper, the performance of the hierarchical modulation in AT-DMB system is analyzed with computer simulation in several environments compared with the performance of T-DMB system. Keyword : T-DMB, Advanced T-DMB, hierarchical modulation, mobile broadcasting, OFDM, Turbo code

The Conditional Access Flow Using Smart Card With KOREASAT Digital DBS Receiver

The KOREASAT Digital DBS System adopted MPEG-2 digital compression and multiplex. The KOREASAT Digital DBS system provides a conditional access service. The conditional access service is that only subscribers who pay receiving fee can watch programs. This paper presents the conditional access flow mechanism using subscriber smart card with KOREASAT Digital DBS Receiver.

Channel Allocation and Interference Analysis for DAB System in Frequency Band III Environment With Legacy T-DMB

For Eureka-147-based digital audio broadcasting (DAB) system, frequency band III has been generally used in many countries. However, in some countries, other legacy broadcasting services have been adopted in the same frequency band. Especially, in South Korea, T-digital multimedia broadcasting (DMB) service has been already broadcasted through the band III since early 2005. In this paper, to adopt the DAB system in band III, channel allocation method and interference analysis are investigated for Korea broadcasting environment with legacy T-DMB. To allocate DAB channel, actual FM radio broadcasting stations and geographical features are considered. Furthermore, interference analysis and evaluation are performed between co-channel broadcasting areas and adjacent channel broadcasting areas. These evaluation results provide the DAB service channel allocation method in broadcasting environment with legacy broadcasting system, and can be used as a reference to determine the DAB service channel allocation through the frequency band with existing broadcasting system.

Mobile multimedia applications: Speech enabled location based data services

This paper presents the speech enabled location based data services by employing the location associated elements to VoiceXML. Specifically, <;location> elements and the related system behaviors are defined and integrated into the Voice Applications. Besides, we implemented the Voice Applications platform with the GPS emulator to verify the location functionalities. With this new feature, the position of user on the move can be triggered to the Web pages which can be presented in a spoken, visual way or concurrent way.

Mobile multimedia broadcasting applications: Speech enabled data services

This paper introduces a service framework of voice applications for mobile multimedia broadcasting featuring the “multimodal” concept which enables user interaction via speech and conventional GUI interfaces concurrently. We present the profiling of VoiceXML to develop a mobile version of speech enabled data service platform. In addition, the synchronization management, the broadcasting network interface and the GPS interfaces are newly defined for the mobile context.

An Implementation Of Digital Dbs Encoder With Dvb Scrambler

Koreasat DBS(Digita1 Broadcasting Satellite) system is composed with 3 subsystems such us RSMS (Resources and Subscribers Management System), TSS(Trunsmitter Station Subsystem), and DBS receivers. In order to implement the CAS(Conditi0nal Access System), DBS video/audio program should be scrambled by D VB(Digita1 Video Broadcasting) scrambler. This paper shows how the video/audio encoder should work with other subsystem such as RSMS and MUX(MuUltiplexer). Also, we introduce how to implement the video/audio encoder with DVB scrambler which is to scramble video/audio programs. In addition, it describes how we control program for subscription and pay-per-view channels.