Coverage Prediction for ATSC interference form ISDB-T system

According to the rapid development of the digital technology, the broadcasting environments are changing into the digital television transmission including the ATSC, ISDB-T, Digital Video Broadcasting – Terrestrial (DVB-T), etc of the high quality and high-efficiency from the existing analog television transmission. In the transition to digital broadcasting, the methods that can efficiently use the limited broadcasting frequency resources are studied in many countries. Particularly, in the digital television broadcasting environment, since the countries using the different digital television broadcasting system(for example ATSC in Korea, ISDB-T in Japan) is positioned nearby, the interference is generated each other and the frequencies are unable to be efficiently used. Therefore, the mutual interference effect must be analyzed through setting up the Protection Ratio(PR) which is interference allowed value between the different broadcasting systems. The PR is the minimum value of wanted-to-unwanted signal ratio, usually in decibels (dB) at the receiver input. By this analysis, the digital broadcasting channel must be arranged to minimize the interference, then the broadcasting frequencies can be efficiently shared and used. In this paper, we measured the PR of the ATSC broadcasting system from the ISDB-T broadcasting system through the laboratory test. By using the measured PR value, the coverage prediction considering the interference was performed between the adjacent nations which use the different digital broadcasting system.