論文ID: 2021EAL2109
Codebooks with small maximal cross-correlation amplitudes have important applications in code division multiple access (CDMA) communication, coding theory and compressed sensing. In this letter, we design a new codebook based on a construction of Ramanujan graphs over finite abelian groups. We prove that the new codebook with length K = q + 1 and size N = q2 + 2q + 2 is asymptotically optimal with nearly achieving the Levenshtein bound when n = 3, where q is a prime power. The parameters of the new codebook are new.