Data Delivery System with Convergence of Terrestrial Digital Broadcasting and Communication for Cellular Phone

In Japan, a terrestrial digital broadcasting service for cellular phone will start for the first time in the world in April, 2006. We already prototyped a cellular phone terminal with terrestrial digital broadcasting function. The evaluation result indicated the need of a quick recovery mechanism for packet loss error of broadcasted data. In addition, an efficient mechanism for developing collaborated applications which fully utilize the both-way communication capability of the broadcasting service with cellular phones as the uplink is expected. However simply transmitting the audience's information (e.g. user account information, channel selection and his/her location) via the cellular phone may cause traffic burden on the cellular network. In this paper we propose a new packet loss recovery mechanism which uses the cellular network for retransmitting the lost packets. Next, we propose a gateway architecture for upload information to reduce the traffic from the terminals to solve the second issue. We demonstrate the effectiveness of these mechanisms through the evaluation using the prototype terminal. We also show the detail implementation of the prototype terminal.