COMMUNICATION SYSTEM, COMMUNICATION TERMINAL, COMMUNICATION METHOD, CHIP CLOCK GENERATION METHOD, AND ORTHOGONAL CODE GENERATION METHOD

摘要

When a plurality of communication terminals (1) access a base station by using CDMA involving the spreading of a transmission signal with an orthogonal code, the orthogonal codes of CDMA signals transmitted from the communication terminals (1) are synchronized on a communication channel. Each of the communication terminals (1) is provided with: an information acquisition unit (310) that acquires reference time information common to the communication terminals (1); a transmission timing generation unit (23) that generates a chip clock with reference to the time information; an orthogonal code generation unit (22) that generates an orthogonal code in synchronism with the timing of the chip clock; a CDMA spreading unit (21) that generates a code division multiple access signal by spreading the transmission signal with the orthogonal code; a carrier wave generation unit (26) that generates a carrier wave; and a BPSK modulation unit (25) that modulates the carrier wave generated by the carrier wave generation unit (26) with the code division multiple access signal for transmission.