| 摘要 |
PROBLEM TO BE SOLVED: To attain network management at all times by providing a cable MODEM required for 2-way communication between a terminal equipment and a CATV center station in a network utilizing the CATV to an adaptor. SOLUTION: A cable MODEM that conducts modulation/demodulation and communication control for 2-way communication between a terminal equipment 50 and a communication system of a CATV center station 1 is provided for adaptors 30, 31,... of houses. A MODEM 155 of the adaptor demodulates a video image, an audio signal and a control signal transmitted from a lobby interphone set 61, outputs the demodulated signal to a house information panel 70, modulates a received audio signal and sends it to the lobby interphone set 61, and an RF modulator demodulates the video and audio signal from the lobby interphone set 61 and the modulates the signal again and provides an output of the modulated signal to the television receiver 50. The power is always supplied to the adaptors 30,... and so long as power is failed in the multiple dwelling house, the adaptors conduct address management and operating state management of each cable MODEM in the CATV center station 1. |
