The Design Of The ZCZ Sequence Pair Set In The Quasi-Synchronous CDMA System

In the quasi-synchronous CDMA system, the request to adopt the spreadingsequence is that the sequence should have perfect correlation properties in thesynchronous error (near the zero time delay), the zero-correlation zone (ZCZ)sequence is just fit for the need. After summarizing and comparing the knowndesign methods of ZCZ sequence, to alter the deficiency of the binary ZCZsequence, applying the sequence pair theory and combining the properties ofZCZ sequence, the paper defines a multi-value self-correlation sequence pair(ZCZ sequence pair) which has zero correlation zone. Based on these matters,the paper makes a series of theory study for the ZCZ sequence pair set. Themain work is just as following:(1)The basic concepts of sequence pair, the correlation properties of thesequence pair and the applications of the sequence pair in the signal process andcommunication system are introduced.(2)The paper presents the definition of the ZCZ sequence pair, and extendsto the definition of the ZCZ complementary sequence pair. The paper alsodiscusses the necessary condition of the being of ZCZ sequence pair, peak valuecharacteristic, construction methods and the transform properties of theself-correlation function. (3)The paper defines the concept of the ZCZ sequence set, presents andproves the several transform properties of the ZCZ sequence set. The paperdeduces the theory bound of the ZCZ sequence set, and also combining thestudy actuality of zero correlation sequence makes some discussion about thebound. The paper presents two construction methods of the ZCZ sequence pair.The ZCZ sequence sets which are constructed by the two methods can approachor get the upper bound. Finally, through comparing with the common ZCZsequence the paper makes some analysis about the performance of the ZCZsequence pair set.(4)The paper summarizes the design methods of ZCZ sequence, presents anew means to structure binary ZCZ sequence: that is step link method. Throughcomparing with the known structure methods, the text makes integratedevaluation to the step link method. At last, the paper introduces two applicationsof the ZCZ sequence in the practice system.The result indicates that the ZCZ sequence pair set is a peculiar binary zerocorrelation sequence. At the same time, its performance is perfect, it is befittingto use as the spread spectrum sequence in the quasi-synchronous CDMA system.