Efficient Generation and Correlation of Sequence Pairs With Three Zero-Correlation Zones

This paper presents three novel methods to efficiently generate and correlate sequence pairs with three zero correlation zones in the sum of their aperiodic correlation functions. These sequences have achieved great importance in communications systems when the maximum transmission delay is less than the length of these zones, because the multiple access interference (MAI) and the intersymbol interference (ISI) can be removed. The proposed algorithms are based on the properties of complementary sets of sequences (CSS) and they offer an efficient hardware implementation of the corresponding generators and correlators that reduces the total number of operations to be performed in comparison with straightforward implementations. That makes possible real-time operation as well as the use of very long sequences.