In recent years, multicarrier communication has attracted considerable attention as a promising technology that enables transmission of high data rates. One of major drawbacks of multicarrier communications is the high peak-to-average power ratio (PAPR) of transmitted signals. Sequences and codes can be used as a solution to handle this problem.;This thesis focuses on the correlations and the power characteristics of special classes of binary sequences with ideal two-level autocorrelation. The aperiodic autocorrelations of the four classes of sequences with length n = 2m - 1 are calculated and analyzed via merit factors, peak sidelobe levels (PSL), and average sidelobe levels (ASL). It is shown that merit factors of 3-term, 5-term and Welch-Gong sequences asymptotically approach to 3.0. Moreover, new growth rates of PSLs and ASLs of these sequences are conjectured. The power characteristics are calculated and discussed via peak-to- mean-envelope-power ratios (PMEPR) of the four classes of sequences with short length n = 2 m - 1 (5 ≤ m ≤ 8) , where PMEPRs give the upper bounds of PAPRs. Also, the PMEPRs of orthogonal codes generated by the sequences are calculated. Compared to the PMEPRs of Walsh code sets, it is claimed that the orthogonal codes generated by binary sequences can replace Walsh codes to obtain small PAPRs in multicarrier communications.
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