From the introduction: Code-Division Multiple-Access (CDMA) allows several users simultaneous access to a common channel by assigning a distinct code or signature sequence to each user, enabling him to distinguished his signal from those of the other users. It is desirable to have large sets of sequences possessing low values of \(C_{\max}\), maximum magnitude of the periodic cross-correlation and out-of-phase auto-correlation, to minimize interference as well as to help synchronization. Optimal binary sequences have been studied extensively and used in binary phase shift keying modulated CDMA communication systems. Such sequences are optimal in terms of having the minimum possible value of \(C_{\max}\) for the given famly size and symbol alphabet. In recent years, quadriphase sequences for use in QPSK modulated CDMA communication systems have been studied. Motivated by these results and by code constructions over \(Z_4\), we find the correlation distribution of the Kasami code over \(Z_4\). From the correlation distribution of the quaternary Kasami code, the weight distribution also follows.
For the entire collection see [Zbl 0974.00035].