Secret key generation method based on reconstructed discrete power system
Technical Field
The invention relates to the field of information safety, in particular to a chaotization method and a chaos sequence generation method of a high-dimensional power system.
Background
The existing general chaotic design method mainly depends on Chen-Lai algorithm, and gives an initial state x0For control system x1=f0(x0)+B0x0Calculate its jacobian matrix
J0(x0)=f0'(x0)+B0x0,
And remember T0=J0(x0). Get B0x0=σ0I and selecting a constant sigma0> 0 such that the matrix [ T0T0 T]Limited and diagonal predominance. For k 0,1,2, consider a control system
xk+1=fk(xk)+Bkxk,
In the formula Bkxk=σkI has been determined from the previous step. Now the following calculations are made:
step 1, calculating a Jacobian matrix
Jk(xk)=fk'(xk)+Bkxk
Note Tk=JkTk-1。
Step 2, selecting a constant sigmak> 0, so that the matrix
[TkTk T]-e2kcI
Limited and diagonal predominance, wherein the constant c > 0 satisfies 0 < c ≦ λi(x0)<∞,i=0,1,2,...,n,。
And 3, performing the following modular operation on the control system:
xk+1=fk(xk)+Bkxk(mod1)
the first two steps of the algorithm described above make the Lyapunov (Lyapunov) exponent of the controlled system strictly positive, so that the system trajectory expands in all directions. A simple controller that satisfies steps 1 and 2 is
uk=Bkxk=σkIk,σk=N+ec。
The modulo operation of the third step makes the entire orbit globally bounded.
The Chen-Lai algorithm can only ensure that the chaotic system has positive Lyapunov (Lyapunov) indexes, and cannot realize accurate control on all Lyapunov (Lyapunov) indexes.
Secondly, selecting a discrete dynamic system, and piecing together a positive Lyapunov (Lyapunov) index by using a Jacobian method:
discrete chaotic system with m dimension
The jacobian matrix is:
iterating the jacobian matrix J n timesi=J(x1(i),x2(i)...xm(i) I ═ 0,1,2.. n). Let P be J0·J1·····JnAnd m eigenvalues of the matrix P are λ0,λ1,...,λmThen the Lyapunov (Lyapunov) index is
If a positive Lyapunov (Lyapunov) index exists, the discrete power system has chaotic behavior, the method utilizes parameters to piece together the positive Lyapunov (Lyapunov) index, has no clear design direction, and cannot accurately control the Lyapunov (Lyapunov) index, and the design of the high-dimensional hyperchaotic system is very difficult by utilizing the method.
Disclosure of Invention
Based on the problems, the chaotization of the high-dimensional power system and the chaos sequence generation method thereof are provided, the problems that the high-dimensional hyper-chaos system is difficult to design and the Lyapunov exponent in the chaos system is difficult to control are solved, and all the Lyapunov exponents in the designed chaos system can be well controlled by the method.
The technology adopted by the invention is as follows: a chaotization method of a high-dimensional power system and a chaos sequence generation method thereof are as follows:
discrete power system with m dimensions
Sn+1=ASn modc
Wherein SnIs a state vector (x)1(n),x2(n),x3(n)......xm(n))TAnd A is a constant coefficient matrix,
since there are no non-linear terms in the m-dimensional discrete dynamical system, the jacobian matrix is a, so P ═ anLet m eigenvalues of matrix A be λ0,λ1,...,λmAnd m Lyapunov indexes in the m-dimensional discrete chaos are as follows:
therefore, the eigenvalues of the parameter matrix a determine the lyapunov exponent of the system; the construction method of the parameter matrix A is as follows:
(1) given the Lyapunov index value LE
1,LE
2,...LE
mAnd calculating the characteristic value
The diagonal matrix Lambda based on eigenvalues is constructed as
(2) Designing an m x m dimensional nonsingular matrix q;
(3) calculating parameter matrix A ═ q Λ q-1And the data are brought into the original model to reconstruct a discrete power system;
(4) and taking the initial value of the state vector as an initial key, and generating a chaotic sequence by utilizing the reconstructed discrete power system.
The invention has the following advantages and beneficial effects: the method can realize the accurate control of the Lyapunov exponent, and because the Lyapunov exponent is accurately controlled, a periodic system with a periodic attractor and a system with a stationary point attractor are realized, and the chaotic sequence output by the method has more complex chaotic behaviors.
Drawings
FIG. 1 is a flow chart of a power system for controlling the Lyapunov exponent configuration;
fig. 2 is a diagram of a chaotic sequence generator constructed by using a positive lyapunov exponent.
Detailed Description
The invention is further illustrated by way of example in the accompanying drawings of the specification:
example 1
As shown in fig. 1-2, a chaos method of a high-dimensional power system and a chaos sequence generation method thereof are as follows:
discrete power system with m dimensions
Sn+1=ASn modc
Wherein SnIs a state vector (x)1(n),x2(n),x3(n)......xm(n))TAnd A is a constant coefficient matrix,
since there are no non-linear terms in the m-dimensional discrete dynamical system, the jacobian matrix is a, so P ═ anLet m eigenvalues of matrix A be λ0,λ1,...,λmAnd m Lyapunov (Lyapunov) indexes in the m-dimensional discrete chaos are as follows:
thus, the eigenvalues of the parameter matrix a determine the Lyapunov (Lyapunov) exponent of the system; the construction method of the parameter matrix A is as follows:
(1) given a Lyapunov (Lyapunov) index value LE
1,LE
2,...LE
mAnd calculating the characteristic value
The diagonal matrix Lambda based on eigenvalues is constructed as
(2) Designing an m x m dimensional nonsingular matrix q;
(3) calculating parameter matrix A ═ q Λ q-1And the data are brought into the original model to reconstruct a discrete power system;
(4) and taking the initial value of the state vector as an initial key, and generating a chaotic sequence by utilizing the reconstructed discrete power system.
Example 2
1. Any given 8 eigenvalues greater than 1, such as 40,41,42,43,44,45,46,47, and c is defined as 1. Rounded Lyapunov (Lyapunov) indices are 3.69,3.71,3.74, 3.76,3.78,3.81,3.83,3.85.
2. A non-singular matrix q is defined as:
where the element q (i, i) is 2, i is 1,2,3.. m, and the remaining elements are all 1. It is easy to prove that q is a non-singular matrix. When m is 8, q may be defined
And the rounded inverse matrix q-1Is composed of
3. The parameter matrix is
And reconstructing the discrete power system.
(4) And taking the initial value of the state vector as an initial key, and generating a chaotic sequence by utilizing the reconstructed discrete power system. The quantization is 1 when the output sequence is greater than 0.5 and 0 when the output sequence is less than 0.5.
Example 3
The effect of the present invention can be further illustrated by the following detection results of this embodiment:
1. the detection method and the content are as follows:
the randomness of the chaotic sequence output by the chaotic sequence generator in embodiment 2 of the present invention is detected by using the SP800-22 random number detection standard provided by national institute of standards and technology, NIST, wherein the detection standard comprises 15 detection contents, and a detection result generated by each detection contains a P value. When the P value is larger than 0.01, the detection content is passed.
2. And (3) detection results:
referring to example 2, 100 sets of 10000000 random sequences were generated and tested using the SP800-22 random number test standard provided by the national institute of standards and technology NIST, wherein one set of results are shown in tables 1-8:
TABLE 1 x1(n) output sequence testing
TABLE 2 x2(n) output sequence testing
TABLE 3 x3(n) output sequence testing
TABLE 4 x4(n) output sequence testing
TABLE 5 x5(n) output sequence testing
TABLE 6 x6(n) output sequence testing
TABLE 7 x7(n) output sequence testing
TABLE 8 x8(n) output sequence testing
The 100 groups of data are tested, and the passing rate value is not lower than 0.96.