A pair of quadriphase sequences whose aperiodic auto and cross-correlation functions take pure imaginary values

Sequences and sequence pairs with imaginary correlation sidelobes

“…the real and imaginary part of sðnÞ have to form a complementary sequence pair as defined by Golay in Reference [6]. To obtain uniform IS with elements sðnÞ 2 fAE1; AEjg, Matsufuji et al [4,5] defined an IS with a suitable factor as…”

“…Furthermore, the number of known perfect periodic binary and quadriphase sequences is very limited [1][2][3]. Matsufuji, Suehiro and Kuroyanagi [4,5] have considered the construction of quadriphase sequences and sequence pairs with purely imaginary sidelobes of their aperiodic autocorrelation and crosscorrelation functions. The notion behind this approach is that if only the real part of the correlation function is considered, these sequences are equivalent to perfect sequences.…”

“…The original work by Matsufuji et al [4,5] considered only quadriphase aperiodic sequences. In this paper, we extend their results to periodic and odd-periodic cases.…”

A new class of Quadriphase Even-Shift Orthogonal Sequences

“…Imaginary Sequences (IS), on the other hand, have ideal real aperiodic correlation functions [6], so they can be used for timing synchronization and time domain channel estimation in communication system. Motivated by Matsufuji's methods, Lüke et al developed some efficient ways to obtain quadriphase and 8-phase sequences and sequences pairs with imaginary correlation sidelobes [7].…”

Construction of complementary arrays

“…Recently those have been discussed for application to CDMA communications [7]- [9], because of the good correlation property.…”