To provide a CATV system that can make Internet service by using the same CATV network even when a utility charge system of a user is a meter rate charge system or a fixed rate charge system.
The CATV system is a system where a CATV device making CATV broadcast and subscriber devices receiving the broadcast mutually transmit/receive data via a CATV network, each subscriber device has a uniquely set modem serial number as subscriber information, and the CATV device is provided with a control means that retrieves subscriber information with respect to a subscriber stored in a charging information table, a frequency changeover means that selects a frequency area of a carrier to transmit/receive a data signal on the basis of the subscriber information provided with a subscriber device retrieved by the control means and a center modem that transmits the data signal in two ways for a prescribed frequency area by using a CATV transmission line.
SAITO TAKAHISA
YAMADA MASAO