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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 world's 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. [ABSTRACT FROM AUTHOR]

As the broadcasting communication R&D subject supported by the government is diversifying gradually, it becomes more difficult to prioritize investment of limited resources. In this respect, the importance of a strict and objective evaluation index for the national R&D project is growing much bigger in using available resources to achieve the corresponding goal by the R&D project. In addition, recently, the importance of a method to effectively express and evaluate achievement of targets, selection of projects and allocation of resources etc. in the whole process of the national R&D project is being emphasized for the scientific national R&D project. To improve efficiency and effectiveness of the process to select the broadcasting communication R&D project, therefore, this study would like to investigate methodologies and models to select projects including more systematic and scientific verification systems and indexes etc. for the R&D planning suitable for the broadcasting communication field focused on major precedent studies and advanced cases and to derive a method to improve them. [ABSTRACT FROM AUTHOR]

Eight microwave links operating at frequencies ranging from 6 to 8 GHz and with path lengths ranging from 5.7 to 37.4 km traversing the city of Seoul, Korea are used to detect rainfall and estimate path-averaged rainfall rates. Rainfall detection using rain-induced attenuation (dB) was validated by rain detectors installed at automatic weather stations, and the results confirmed that microwave links can be used to detect rainfall with an accuracy ≥80%. The power-law R-k relationships between rain-induced specific attenuation, k (dB km−1), and the rainfall rate, R (mm h−1), were established and cross-validated by estimating the path-averaged rainfall rate. The mean bias of the path-averaged rainfall rate, as compared to the rainfall rate from ground rain gauges, was between −3 and 1 mm h−1. The improved accuracy of rainfall detection led to the improved accuracy of the path-averaged rainfall rate. Hence, it was confirmed that microwave links, used for broadcasting and media communications, can identify rainy or dry periods (rain spells or dry spells) in a way comparable to rain detectors and provide high time-resolution rainfall rates in real time. [ABSTRACT FROM AUTHOR]