An Earthquake Early Warning (EEW) is a service of Japan Meteorological Agency (JMA), which issues the advance warning of a large-scale earthquake before the arrival of its main tremor when it occurs. The service is based on the prompt estimation of the focus and magnitude of the earthquake by analyzing its initial tremor observed near the epicenter. NHK has been automatically broadcasting JMA's EEW on television and radio programs as soon as it is issued. The Japanese digital terrestrial television broadcasting system has special carriers called Auxiliary Channel (AC) besides the main signals of video, audio and so on. ACs have advantageous characteristics to be used for the broadcast of an EEW: short delay transmission without any data compression coding such as video or audio information and channel coding such as data interleaving during transmission; robustness against noise and interference due to the use of DBPSK modulation. We studied a transmission of ACs in One-Seg to carry the information of an EEW. The results showed the promising good transmission characteristics under noise and fading environments.
