HIGH-SPEED MULTICARRIER SPREAD SPECTRUM COMMUNICATION SYSTEM

PROBLEM TO BE SOLVED: To provide a high-speed multicarrier spread spectrum communication system which can significantly improve frequency utilization efficiency in a multicarrier system. SOLUTION: A transmitter T1 has a serial-parallel conversion unit 1, direct spead units 2, a multicarrier modulation unit 3 which modulates respective output data of the direct spread units 2 having different carriers to outputs multicarrier signals, and an antenna 4 for sending out the multicarrier signals in the air. A receiver R1 has an antenna 5 for receiving the multicarrier signals, a multicarrier demodulation unit 6 which separates the received multicarrier signals into data with respective different carriers, inverse-spread units 7, limiters 8 which convert the respective output data of the inverse-spread units 7 into positive or negative polarity information, and a parallel/serial conversion unit 9. The multicarrier modulation unit 3 makes the intervals between the different carriers equal to one-fourth of the symbol rates of the output data of the serial/parallel conversion unit 1.