In this paper, the autocorrelations of maximal period Feedback with Carry Shift Register sequences (l-sequences) are discussed. For an l-sequence a with connection integer q = p^e(e ≥ 2) and period T = p^t-1(p- ...In this paper, the autocorrelations of maximal period Feedback with Carry Shift Register sequences (l-sequences) are discussed. For an l-sequence a with connection integer q = p^e(e ≥ 2) and period T = p^t-1(p- 1), and for any integer i, 1 ≤ i ≤ e/2, by calculating the number of certain sets, it is shown that the autocorrelation of a with shift τ= kT/2p^i is Ca(τ) =(-1)^k-1 T/p^2i-1, where 1 ≤ k ≤ 2p^i - 1, and gcd(k,2p^i) = 1. This result shows there do exist some shifts such that the autocorrelations of l-sequences are high although most autocorrelations are low. Such result also holds for the decimations of l-sequences.展开更多
The linear complexity of a new kind of keystream sequences.FCSR sequences,is discussed by use of the properties of cyclotomic polynomials.Based on the results of C.Seo's,an upper bound and a lower bound on the li...The linear complexity of a new kind of keystream sequences.FCSR sequences,is discussed by use of the properties of cyclotomic polynomials.Based on the results of C.Seo's,an upper bound and a lower bound on the linear complexity of a significant kind of FCSR sequences—l-sequences are presented.展开更多
基金the 863 Project of China (No.2006AA01Z417) the National Natural Science Foundation of China (No.60673081).
文摘In this paper, the autocorrelations of maximal period Feedback with Carry Shift Register sequences (l-sequences) are discussed. For an l-sequence a with connection integer q = p^e(e ≥ 2) and period T = p^t-1(p- 1), and for any integer i, 1 ≤ i ≤ e/2, by calculating the number of certain sets, it is shown that the autocorrelation of a with shift τ= kT/2p^i is Ca(τ) =(-1)^k-1 T/p^2i-1, where 1 ≤ k ≤ 2p^i - 1, and gcd(k,2p^i) = 1. This result shows there do exist some shifts such that the autocorrelations of l-sequences are high although most autocorrelations are low. Such result also holds for the decimations of l-sequences.
基金The work is supported by the Special Fund of National Excellently Doctoral Paper and HAIPURT.
文摘The linear complexity of a new kind of keystream sequences.FCSR sequences,is discussed by use of the properties of cyclotomic polynomials.Based on the results of C.Seo's,an upper bound and a lower bound on the linear complexity of a significant kind of FCSR sequences—l-sequences are presented.