METHOD FOR GENERATING COMPLEX QUASI-ORTHOGONAL CODE AND APPARATUS AND METHOD FOR SPREADING CHANNEL DATA USING THE QUASI-ORTHOGONAL CODE IN CDMA COMMUNICATION SYSTEM

摘要

A method for generating a complex quasi-orthogonal code for channel spreadin g in a CDMA communication system is disclosed. The method comprises generating an M-sequences having a length N and a specific sequence having a good full correlation property with the M-sequence; generating a predetermined number of other specific sequences by circularly shifting said specific sequence; generating a predetermined number of other M-sequences by circularly shiftin g said M-sequence, and column permutating the circularly shifted specific sequences in a same method as a column permutating method for converting the generated M-sequences to Walsh orthogonal codes to generate canditate masks; generating quasi-orthogonal code representatives by operating the canditate masks and the Walsh orthogonal codes having the same length as the mask candidates; and selecting quasi-orthogonal codes out of the generated quasi- orthogonal code representatives and a partial correlation between different quasi-orthogonal codes, and selecting masks pertinent to generating the selected quasi-orthogonal codes.