Ofdm generation apparatus in a multi-carrier data transmission system

PURPOSE: An OFDM generation apparatus in a multi-carrier data transmission system is provided to prevent the common phase rotation of an OFDM subcarrier by mixing the plural time domains of an OFDM symbol from a baseband frequency and a pass band frequency. CONSTITUTION: In an OFDM generation apparatus in a multi-carrier data transmission system, a transmitter(1) collects an OFDM transmission signal. The transmitter comprises a transmitter unit(11) for supplying the collected OFDM transmission signal to a cable network(3). A receiver(2) comprises a receiving unit(20) and an OFDM decoder(21). The receiver unit receives the OFDM transmission signal from the cable network. An OFDM decoder decodes the OFDM transmission signal into an OFDM symbol.