Patent ID: 6963601
Filing Date: 2005-11-08
Classification: H04B,H04J

Abstract:
1. A channel spreading method in a CDMA (Code Division Multiple Access) communication system which spreads a pair of symbols obtained by repeating a first symbol with a quasi-orthogonal code having a given length to transmit the spread symbols through a first antenna and spreads a second symbol and an inverted symbol of said second symbol obtained by repeating said second symbol with said quasi-orthogonal code to transmit the spread symbols through a second antenna at the same time, the method comprising the steps of: spreading one of said pair of symbols obtained by repeating said first symbol with a portion of said quasi-orthogonal code and spreading another symbol of said pair of symbols with a remaining portion of said quasi-orthogonal code; spreading the second symbol with a portion of said quasi-orthogonal code and spreading said inverted symbol of said second symbol with the remaining portion of said quasi-orthogonal code; generating a mask index and a Walsh code index corresponding to an input index for generating the quasi-orthogonal code; generating a mask for the quasi-orthogonal code corresponding to the mask index, and generating a Walsh code corresponding to the Walsh code index; and outputting, as the quasi-orthogonal code, a quasi-orthogonal code generated by mixing a mask for the generated quasi-orthogonal code with the Walsh code.