Scrambling system and method for peak power reduction in MC-CDMA, and recording medium for storing corresponding program

A communication method in multicarrier code division multiple access (MC-CDMA), comprising:

• (a-1) modulating a bit stream of at least one user having an orthogonal code combination into modulation symbols, multiplying the respective modulation symbols by an orthogonal code Ck, and spreading them into chip sequences;
• (a-2) adding the chip sequences spread by said modulating in synchronization with symbol timing, interleaving the chip sequences of M symbols that will be transmitted in parallel, and arranging the chips belonging to an identical symbol by an M chip interval;
• and
• (a-3) converting the chip sequences arranged by said adding into parallel chip signals having a number of subcarriers, multiplying the parallel chip signals by a fixed scrambling code which is predetermined according to the at least one user's orthogonal code combination, modulating each chip for each subcarrier through inverse fast Fourier transform, and generating and outputting multicarrier signals.

A recording medium storing a program having instructions for causing a computer to execute a method comprising:

• (a) modulating a bit stream of at least one user having an orthogonal code combination into modulation symbols, multiplying the respective modulation symbols by an orthogonal code Ck, and spreading them into chip sequences;
• (b) adding the chip sequences spread in (a) in synchronization with symbol timing, interleaving the chip sequences of M symbols that will be transmitted in parallel, and arranging the chip sequences belonging to an identical symbol by an M chip interval;
• and
• (c) converting the chip sequences arranged in (b) into parallel chip sequence signals, multiplying the parallel chip signals by a fixed scrambling code which is predetermined according to the at least one user's orthogonal code combination, modulating each chip for each subcarrier through inverse fast Fourier transform, and generating and outputting multicarrier signals.