Patent ID: 7366227

Claim:
A method for despreading a received spreaded code as a function of a correlation code, comprising the steps of: generating a despreading output as a function of said received spreaded code and said correlation code, said despreading output sample being identified by a despreading output index; identifying the index of the particular despreading output sample having the maximum absolute value of all of said despreading output sample, k max ; and mapping said k max to a symbol in a set of symbols, said set of symbols corresponding to information encoded in said received spreaded code, wherein said correlation code is generated from a symbol in said set of symbols that has been mapped into a set of differential encoded PN codes, said correlation code being generated by the following steps: selecting a symbol from said set of symbols; mapping said selected symbol to form a mapped symbol; upsampling said mapped symbol; repeating said upsampled symbol; and after repeating said upsampled symbol, cyclically shifting said repeated upsampled symbol to the right to form said correlation code.