Digital Mobile TV Launched In Japan

Australian IT: Broadcast mobile TV has launched in Japan, under the name one-seg, short for one segment. I can’t find any details of the technology used, just that it’s digital and the phone batteriers will therefore last for three hours rather than the one hour they lasted for the analogue signal. I know Japan had its own standard, ISDB-T, and I assume this is what the carriers are using.
From all accounts the mobile TV service is provided free with carriers and broadcasters hoping to recoup costs by offering watchers the chance to purchase things and respond to advertising interactively. Initially the shows will be the same as on TV, but I’m guessing that will change. Also: “NTT DoCoMo has tied up with Nippon Television and Fuji Television. DoCoMo’s main rival, KDDI, has forged a partnership with TV Asahi.”
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