METHOD AND APPARATUS FOR MC/MC-DS DUAL-MODE SPREADING FOR ADAPTIVE MULTICARRIER CODE DIVISION MULTIPLE ACCESS SYSTEM

摘要

PURPOSE: An adaptive MC(Multi-Carrier)-CDMA device capable of performing a direct sequence conversion function is provided to independently vary reciprocal conversions between an MC-DS(Direct Sequence) CDMA system and an MC-CDMA system as well as each user modulation degree and a repeated transmission degree, thereby reducing an additional signal processing. CONSTITUTION: A user signal processor performs symbol modulation, repetition, and spread processes according to transmission methods appropriate for channel environments of each user relating to bit strings of each user. A synthesizer(210) synthesizes all chip strings of the users. The first interleaving processor(211) receives the added chip strings, and performs an interleaving process. The second interleaving processor(212) selectively performs an additional interleaving process for a signal transmitted from the first interleaving processor(211), depending on whether a determined direct sequence system is an MC-DS CDMA system or an MC-CDMA system.