Two Classes of Codebooks Nearly Meeting the Welch Bound
Aixian Zhang, Keqin Feng · IEEE Transactions on Information Theory · 2011
In this paper, the value of Imax(C) for codebooks C = C(D) constructed by certain almost difference sets D in Fqxis determined and expressed in terms of Jacobi sums from which it shows that such codebooks nearly meet the Welch bound. This result is an answer of a question raised by C.Ding and T.Feng in [2]. We also present another series of codebooks which nearly meet the Welch bound, where the codebook is constructed by a subset R = Fq1⊕ Fq2. When q1= q2, Dεis an almost difference set of R.