This paper presents a process variation sensing circuit technique for maintaining the performance benefit of CMOS digital circuits and reducing variations in delay and robustness. The new process sensor consists of two inverter chains with different loading capacitances and a time-to-digital converter (TDC) that detects delay variations between the inverter chains. Results based on the measured TDC data are used to adjust the supply voltages of systems to optimal values. This technique considerably saves power in digital circuits and increases yield in high performance bins. In order to verify the operation and performance of the novel sensor, an all-digital delay-locked-loop (DLL) was designed and its jitter was measured. The circuits, which were fabricated with a 0.13um CMOS process, showed the 20% improved jitter variations compared with a conventional DLL without process compensation.

Large prime numbers are one of inevitable ingredients in the public key crypto-systems. However, the decision of the primality requires significant computational resources. In this paper, we proposed two efficient methods to generate large prime numbers. Firstly, an accelerating method by utilizing pre-installed modular multiplier which is used to calculate public key algorithm is proposed. Secondly, new improved algorithm which reduces computational resources is presented. In the latter algorithm, the requirement for the related parameters are reinforced in order to prevent generating random numbers with small prime factors. In addition, by slightly releasing the requirement for the parameters, it is possible to remove the unit generation procedure in Joye and Paillier's scheme. Through these modifications, it is possible to obtain new efficient prime number generation algorithm.

In this paper, a new generation method of quaternary sequences of period 2(2n-1) with ideal autocorrelation and balance property is proposed using the binary sequences of period 2n- 1 with ideal autocorrelation and reverse Gray mapping. The autocorrelation distribution of the proposed quaternary sequences is also derived.

In this paper, for an odd prime p, new quaternary sequences of even period 2p with ideal autocorrelation property are constructed using the Legendre sequences of period p. The distribution of autocorrelation function of the proposed quaternary sequences is also derived.

We propose a new construction of quaternary sequences using the reverse Gray mapping of a pair of binary Sidel'nikov sequences. The proposed construction provides sequences of even period N with the maximum nontrivial auto-correlation magnitude, Rmax= 2. For N ≡ 0 mod 4, the new quaternary sequences have the optimal Rmax= 2 and are almost-balanced in contrast to the only earlier optimal construction Sj[1].

In this paper, a new extending method of q-ary low correlation zone(LCZ) sequence sets is proposed, which is a generalization of binary LCZ sequence set by Kim, Jang, No, and Chung. Using this method, q-ary LCZ sequence set with parameters (N,M,L, isin) is extended as a q-ary LCZ sequence set with parameters (pN, pM, plfloor(L + 1)/plfloor - 1, pisin), where p is prime and p|q.

In this paper, we proposed a new quaternary low correlation zone(LCZ) sequence set with parameters (2(2n− 1),M, L, 2). The new LCZ sequence set is constructed from the binary sequence with ideal autocorrelation of period 2n− 1. The proposed construction method corresponds to the generalization of the construction method of binary LCZ sequence set by using binary sequence with ideal autocorrelation proposed by Kim, Jang, No, and Chung [1].

In this correspondence, three methods of constructing low-correlation zone (LCZ) sequences are proposed. In the first method, we constructed binary LCZ sequence sets of period 2n-1 using the Legendre sequences of period 2m-1 as a column sequence when m|n. In the second method, we devise a column sequence set of length 2m+1-1 from a binary sequence of period 2m-1 having ideal autocorrelation property and this column sequence set is used to construct binary LCZ sequence sets of period 2n-1 when (m+1)|n. In the third method, p-ary LCZ sequence sets are constructed by adopting p-ary sequence of period pm-1 with ideal autocorrelation for integers n and m such that m|n as a column sequence. The second and third methods give us the optimal sets with respect to the bound by Tang, Fan, and Matsufuji. Finally, a construction method of pntimespnp-ary Hadamard matrices from optimal LCZ sequence sets is proposed

In this paper, we propose the new construction methods of constructing optimal low correlation zone (LCZ) sequences. We construct the new p-ary LCZ sequence sets by adopting p-ary sequence of period pm- 1 with ideal autocorrelation for integers n and m such that m n as a column sequence. The new construction methods give us the optimal sets with respect to the bound by Tang, Fan, and Matsufuji

In this paper, given an integer e and n such that e|n, and a prime p, we propose a method of constructing optimal p2-ary low correlation zone (LCZ) sequence set with parameters (pn- 1,pe- 1, (pn- 1)/(p - 1), 1) from a p-ary sequence of the same length with ideal autocorrelation. The resulting p2-ary LCZ sequence set can be viewed as the generalization of the optimal quaternary LCZ sequence set by Kim, Jang, No, and Chung in respect of the alphabet size. But the method used in the proof is quite different from that used in the quaternary LCZ sequence. The proof used in this paper can be used for the proof of quaternary LCZ sequence

In this paper, we define quasi-cyclic (QC) generalized Hadamard matrices and balanced QC generalized Hadamard matrices. Then we propose a new construction method for QC generalized Hadamard matrices. The proposed matrices are constructed from the balanced optimal low correlation zone (LCZ) sequence set which has correlation value -1 within low correlation zone

In this paper, we present several construction methods for low-correlation zone (LCZ) sequence sets. First, we propose a design scheme for binary LCZ sequence sets with parameters (2n+1-2,M,L,2). In this scheme, we can freely set the LCZ length L and the resulting LCZ sequence sets have the size M, which is almost optimal with respect to Tang, Fan, and Matsufuji bound. Second, given a q-ary LCZ sequence set with parameters (N,M,L,epsi) and even q, we construct another q-ary LCZ sequence set with parameters (2N,2M,L,2epsi) or (2N,2M,L-1,2epsi). Especially, the new set with parameters (2N,2M,L,2) can be optimal in terms of the set size if a q-ary optimal LCZ sequence set with parameters (N,M,L,1) is used

In this paper, for integers e and n such that e|n and 2e- 1 is a prime, we propose a method of constructing binary low correlation zone (LCZ) sequences of period 2n- 1 by using the extended form sequence with the same period. These new LCZ sequences use Legendre sequences as their column sequences

In this paper, given a composite integer n, we propose a method of constructing quaternary low correlation zone (LCZ) sequences of period 2n$1 from binary sequences of the same length with ideal autocorrelation. These new sequences are optimal with respect to the bound by Tang, Fan, and Matsufuji. The correlation distributions of these new quaternary LCZ sequences constructed from m-sequences and GMW sequences are derived

In this paper, given a composite integer n, we propose a method of constructing quaternary low correlation zone (LCZ) sequences of period 2/sup n/-1 from binary sequences of the same length with ideal autocorrelation. These new sequences are optimal with respect to the bound by Tang, Fan, and Matsufuji. The correlation distributions of these new quaternary LCZ sequences constructed from m-sequences and Gordon-Mills-Welch (GMW) sequences are derived.

In this paper, using p-ary bent functions defined on vector space over the intermediate finite field, we generalized the construction method of the families of p-ary bent sequences with balanced and optimal correlation properties introduced by Kumar and Moreno for an odd prime p, called generalized p-ary bent sequences.

For an odd prime p and integers n, m, and k such that n=(2m+1)k, a new family of p-ary sequences of period p/sup n/-1 with optimal correlation property is constructed using the p-ary Helleseth-Gong sequences with ideal autocorrelation, where the size of the sequence family is p/sup n/. That is, the maximum nontrivial correlation value R/sub max/ of all pairs of distinct sequences in the family does not exceed p/sup n/2/+1, which means the family has optimal correlation in terms of Welch's lower bound. The symbol distribution of the sequences in the family is enumerated. It is also shown that the linear span of the sequences in the family is (m+2)n except for the m-sequence in the family.