Patent ID: 7023903

Claim:
A method of receiving a spread spectrum signal, comprising: receiving a combination signal comprising user signals spread with various spreading codes; generating samples from the received combination signal; selecting a sample set including N successive samples, where N is an integer number of at least two; reading from a sample memory one or more samples belonging to said sample set; reading user signal estimates from a correlation memory, and correlating the samples using the spreading codes and the user signal estimates to generate improved user signal estimates; generating sample estimates for the spread user signals corresponding to the sample by means of user signal estimates and the spreading codes; synchronising the sample memory and the correlation memory in such a way that the user signal estimates are read from the correlation memory to the sample estimate generation stage substantially at the same time as the samples are read from the sample memory to the user signal estimate generation stage; subtracting the generated sample estimates from the sample corresponding to them to generate a residual signal sample; using the residual signal sample in the generation of specified user signal estimates to be used in a following sample estimate generation stage; returning to said sample reading stage until all samples in the sample set that are necessary for generating the user signal estimates are processed; generating final user signal estimates for M oldest samples in the sample set on the basis of the specified user signal estimates generated for them, where M is an integer of at least one; and removing M oldest samples from the sample set and returning to the sample set selection stage by selecting M new samples to the sample set of N samples in addition to the N−M samples belonging to the previous interference-cancelling stage.