| 摘要 |
<P>PROBLEM TO BE SOLVED: To continuously retransmit a broadcasting signal even when the receiving state of the broadcasting signal is deteriorated intermittently with a movement. <P>SOLUTION: Terrestrial digital broadcasting signals are received by antennas 10 and 30 installed to tail and head cars 1-1 and 1-3 in an electric railcar. The broadcasting signal received by either one is multiple-synthesized to transmission cables 18-1 to 18-3 connected astride among cars and transmitted to each car, and retransmitted from retransmitters 21, 23 and 40. In this case, the broadcasting signal on the tail car side is selected preferentially while using the tail car side as a master and the receiving state of the selected broadcasting signal is monitored. The deterioration of a receiving signal is discriminated from the result of monitoring, and then control changeover is conducted for retransmission of the broadcasting signal received by the head car side depending on the degree of the deterioration of the receiving signal. <P>COPYRIGHT: (C)2009,JPO&INPIT |
