Patent ID: 7272168

Claim:
A method for determining the correlation between consecutive sets of samples of a code modulated signal received at a receiver on the one hand and samples of an available replica code sequence on the other hand, a respective next set of samples being formed by adding at least one new sample of said received signal to a current set of samples and by removing at least the oldest sample from said current set of samples, the samples of a respective set of samples and of said replica code sequence being aligned to each other, wherein positions of samples in said replica code sequence are grouped, each of said grouped positions and a predetermined number of respective subsequent positions forming a subgroup and each group comprising the respective first position of all subgroups with positions associated with a similar composition of consecutive samples of said replica code sequence, said method comprising: combining the values of those samples of a first set of samples, which are associated by their position to a respective group, separately for each group to obtain a respective preliminary result; determining a correlation value for each of said sets of samples by combining the obtained preliminary results for all groups separately for each of said sets of samples taking into account for each group the respective composition of consecutive samples of said replica code sequence associated with those subgroups which are associated by their first positions to the respective group, and by adding the products between samples of the respective set of samples and of said replica code sequence at the same position for those positions at which said samples are not comprised in said preliminary results; and using said correlation value for each of said sets of samples to determine the correlation between each of said sets of samples and said replica code sequence.