This paper is devoted to the choice of chaotic spreading sequence for asynchronous DS-CDMA communication.Aiming at the characteristic of asynchronous DS-CDMA system

some criteria on optimizing spreading sequences are proposed.The method of choosing is also presented.According to the method

chaotic spreading sequences with better performance are obtained.Calculation shows that these optimized chaotic spreading sequences are much better than Gold sequences.At last

5 kinds of chaotic sequences' performance are compared.