This invention is a digital signal processor capable of performing correlation of data with pseudo noise for code division multiple access (CDMA) decoding using clusters. Each cluster includes plural multipliers. The multipliers multiply real and imaginary parts of packed data by corresponding pseudo noise data. Within a cluster the real parts and the imaginary parts of the products are summed separately. This forms plural complex number outputs equal in number to the number of clusters. The pseudo noise data is offset relative to the data input differing amounts for different clusters. The clusters are divided into first half clusters receiving data from even numbered slots and second half clusters receiving data from odd numbered slots. The correlation unit includes a mask input to selectively zero a multiplier product.