12 A Search for Barker like Ternary Sequences for Direct Sequence CDMA

The performance of a spread spectrum code division multiple access system depends on the correlation properties of the employed spreading codes. In order to suppress the multiple access interference among the competitive users of the channel it is desirable that, the cross-correlation values between spreading sequences should be as low as possible, and to achieve proper synchronization and to suppress inter-symbol interference the auto-correlation of every sequence should be as peaky as possible. In addition to these two requirements the spread spectrum multiple access communication requires large number of sequences to increase the channel capacity. In this paper we propose Barker like ternary sequences with ortho-normal odd-shift property, and are optimized using combinatorial optimization technique such as Hamming scan.