APPARATUS AND METHOD FOR GENERATING TETRA COMPLEX QUASI-ORTHOGONAL CODE OF CODE DIVISION MULTIPLE ACCESS COMMUNICATION SYSTEM, AND APPARATUS AND METHOD OF SPREADING USING THEREOF

摘要

PURPOSE: An apparatus and a method for generating a quasi-orthogonal code mask for generating tetra complex quasi-orthogonal code giving minimum interference to an orthogonal code, and generating a quasi-orthogonal code for channel classification using the quasi-orthogonal code mask and a Walsh orthogonal code is provided. CONSTITUTION: A method for generating tetra complex quasi-orthogonal code in a code division multiple access communication system comprises the processes of: generating M sequence and specific sequences having good full correlation property; generating a mask candidate by column permutation of the specific sequence based upon the same method as the column permutation method of converting the M sequence into the Walsh code; generating a quasi-orthogonal code representatives by the arithmetic calculation of the mask candidates and the Walsh codes having the same length as the mask candidates; and selecting a quasi-orthogonal code satisfying the partial correlation with the Walsh codes among the generated quasi-orthogonal code representatives, and selecting a mask related with the generation of the selected quasi-orthogonal code.