Safe transmission method based on five-dimensional integer domain chaotic system
阅读说明：本技术 一种基于五维整数域混沌系统的安全传输方法 (Safe transmission method based on five-dimensional integer domain chaotic system ) 是由 陈远祥 鲁帆 邓怡珺 李嘉豪 刘畅 马炳 张橹 程竟爽 余建国 于 2021-08-02 设计创作，主要内容包括：本发明公开了一种基于五维整数域混沌系统的安全传输方法,在发送端,原始发送的数据首先利用产生的x序列进行异或加密,然后经过QPSK映射,映射后的数据利用y和z序列进行置乱加密和利用w和t序列进行插值加密之后,通过RRC滤波器以及HPA后送入卫星信道；在接收端,首先对接收到的信号进行补偿,然后再进行解插值和解置乱,再通过QPSK解调之后通过异或操作,恢复出未加密的信号。本发明通过使用五维的整数域混沌系统进行卫星系统的安全通信,在具有较低复杂度的同时解决了传统的混沌系统由于计算机精度有限导致的混沌动力学退化的短周期现象。(The invention discloses a safe transmission method based on a five-dimensional integer domain chaotic system, at a transmitting end, originally transmitted data are firstly subjected to exclusive OR encryption by utilizing a generated x sequence, then are subjected to QPSK mapping, and after being subjected to scrambling encryption by utilizing y and z sequences and interpolation encryption by utilizing w and t sequences, the mapped data are transmitted into a satellite channel through an RRC filter and HPA; at a receiving end, the received signal is compensated firstly, then de-interpolation and descrambling are carried out, and then the unencrypted signal is recovered through XOR operation after QPSK demodulation. The invention uses the five-dimensional integer domain chaotic system to carry out the safe communication of the satellite system, and solves the short period phenomenon of chaotic dynamics degradation of the traditional chaotic system caused by limited computer precision while having lower complexity.)
1. A safe transmission method based on a five-dimensional integer domain chaotic system is characterized in that an iterative equation of the five-dimensional integer domain chaotic system is expressed as follows:
wherein x, y, z, w and t are chaotic state values of five dimensions, and the value is 0-2N1, N is the number of bits in a binary number representation, Sn、Un、Vn、LnAnd MnIs a unilateral infinite random sequence with the value of 0-2N-1；
The transmission process of the safe transmission method comprises the following steps:
at a transmitting end, the originally transmitted data is firstly subjected to exclusive OR encryption by using a generated x sequence, then is subjected to QPSK mapping, and after the mapped data is subjected to scrambling encryption by using y and z sequences and interpolation encryption by using w and t sequences, the data is transmitted into a satellite channel through an RRC filter and HPA; at a receiving end, the received signal is compensated firstly, then de-interpolation and descrambling are carried out, and then the unencrypted signal is recovered through XOR operation after QPSK demodulation.
2. The safe transmission method based on the five-dimensional integral number domain chaotic system as claimed in claim 1, wherein the XOR encryption equation is expressed as:
where Data is the original unencrypted input Data and x _ sequence is the resulting chaotic sequence.
3. The safe transmission method based on the five-dimensional integral number domain chaotic system as claimed in claim 1, wherein the scrambling encryption method comprises:
grouping data into N groups, wherein each group of data comprises 256 points, taking a generated y sequence as the number of groups to be scrambled, taking a generated z sequence as the position of the data to be scrambled in each group, and then scrambling, wherein N is M/256, M is the number of data, N which cannot be evenly divided by 256 is firstly added with 0 and then evenly divided.
4. The safe transmission method based on the five-dimensional integral number domain chaotic system as claimed in claim 1, wherein the interpolation encryption method comprises:
and taking the value of the w sequence as the position for inserting Data in the Data _ scrambles, taking the value of the t sequence as the position for taking out the inserted Data in the Data _ scrambles, and then inserting the taken out Data into the position represented by the w sequence.
Technical Field
The invention relates to the technical field of satellite communication, in particular to a safe transmission method based on a five-dimensional integer domain chaotic system.
Background
Due to the openness of the wireless channel, the satellite communication is easily threatened by safety, and the guarantee of the satellite communication safety is very important.
The chaotic sequence has the characteristics of initial value sensitivity, unpredictability and pseudo-randomness, so that the chaotic sequence can be effectively applied to the encryption of a physical layer of a satellite communication system to realize safe communication. And the initial value of the chaotic system is used as a key, and the state value of the chaotic sequence is utilized to realize encryption on a physical layer.
For example, document 1(Zhang, x., g.zhu and s.ma, Remote-sensing image encryption in hybrid domains. optics Communications,2012.285(7): p.1736-1743) proposes a new mixed domain image encryption algorithm that performs two-dimensional Logistic mapping diffusion and spatial xor operations on an image reconstructed by IDWT. Document 2(Usama, m., et al., Chaos-based secure image cryptography, computers & Mathematics with Applications,2010.60(2): p.326-337) utilizes various chaotic maps, such as Logistic, Henon, Tent, Cubic, Sine, and Chebyshev, to enhance the key space, robustness, and security of satellite images. However, when the chaotic system is implemented in a hardware device with limited calculation precision, the degradation problem of chaotic dynamics inevitably occurs.
To solve the problem of chaotic dynamics degradation, document 3(Zhongyun, Hua, yigong, & Zhou. (2017). One-dimensional nonlinear model for producing chaos. Document 4(Nagaraj N, Shasty M C, Vaidya P G. incorporated Average Period Switching of Robust Chaos Maps in Fine Precision [ J ]. European Physical Journal Topics,2008,165(1):73-83) proposes to increase the Average Period length of the chaotic sequence by Switching continuously in a plurality of identical or different chaotic systems. Document 5(CN104022863B an integer domain chaotic circuit) realizes a circuit of an integer domain chaotic system.
The existing scheme for solving the problem of chaotic dynamics degradation is carried out in a mode of cascading a plurality of chaotic systems and increasing the calculation precision. Therefore, the cost is increased, the cycle length and the calculation complexity of the period are improved by the scheme of cascading a plurality of chaotic systems, and the problem of uneven distribution of output sequences is introduced. Therefore, the problem of chaotic dynamics degradation is not fundamentally solved by the chaotic system.
Therefore, how to eliminate the degradation of the chaotic dynamics without introducing other problems is a problem to be solved urgently at present.
Disclosure of Invention
The invention aims at the technical problems and provides a safe transmission method based on a five-dimensional integer domain chaotic system, which realizes the safe transmission of a satellite communication system, and simultaneously can fundamentally solve the problem of chaotic dynamics degradation compared with the scheme, and has lower calculation complexity and no other problems.
In order to achieve the above purpose, the invention provides the following technical scheme:
the invention provides a safe transmission method based on a five-dimensional integer domain chaotic system, which is expressed by an iterative equation:
wherein x, y, z, w and t are chaotic state values of five dimensions, and the value is 0-2N1, N is the number of bits in a binary number representation, Sn、Un、Vn、LnAnd MnIs a unilateral infinite random sequence with the value of 0-2N-1；
The transmission process of the satellite secure transmission method comprises the following steps:
at a transmitting end, the originally transmitted data is firstly subjected to exclusive OR encryption by using a generated x sequence, then is subjected to QPSK mapping, and after the mapped data is subjected to scrambling encryption by using y and z sequences and interpolation encryption by using w and t sequences, the data is transmitted into a satellite channel through an RRC filter and HPA; at a receiving end, the received signal is compensated firstly, then de-interpolation and descrambling are carried out, and then the unencrypted signal is recovered through XOR operation after QPSK demodulation.
In the above secure transmission method based on the five-dimensional integer domain chaotic system, the xor encryption equation is expressed as:
where Data is the original unencrypted input Data and x _ sequence is the resulting chaotic sequence.
In the secure transmission method based on the five-dimensional integer domain chaotic system, the scrambling encryption method comprises the following steps:
grouping data into N groups, wherein each group of data comprises 256 points, taking a generated y sequence as the number of groups to be scrambled, taking a generated z sequence as the position of the data to be scrambled in each group, and then scrambling, wherein N is M/256, M is the number of data, N which cannot be evenly divided by 256 is firstly added with 0 and then evenly divided.
In the secure transmission method based on the five-dimensional integer domain chaotic system, the interpolation encryption method comprises the following steps:
and taking the value of the w sequence as the position for inserting Data in the Data _ scrambles, taking the value of the t sequence as the position for taking out the inserted Data in the Data _ scrambles, and then inserting the taken out Data into the position represented by the w sequence.
Compared with the prior art, the invention has the beneficial effects that:
compared with the traditional encryption modes such as AES (advanced encryption standard) and the like, the safe transmission method based on the five-dimensional integer domain chaotic system provided by the invention has the advantages that the calculation complexity is greatly reduced, meanwhile, as the chaotic system provided by the invention is iterated in the integer domain, the precision is determined, the problem of chaotic dynamics degradation is avoided, and the safety of the chaotic encryption system is greatly improved.
Drawings
In order to more clearly illustrate the embodiments of the present application or technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to the drawings.
Fig. 1 is a flowchart of a secure transmission method based on a five-dimensional integer domain chaotic system according to an embodiment of the present invention.
Fig. 2-6 are sequence diagrams generated by the x, y, z, w, t dimensions provided by the embodiment of the invention.
Fig. 7 is a sequence diagram of encryption without position scrambling according to an embodiment of the present invention.
Fig. 8 is a sequence diagram of the location scrambled encryption according to the embodiment of the present invention.
Fig. 9 is a sequence diagram of non-interpolation encryption according to an embodiment of the present invention.
Fig. 10 is a sequence diagram of interpolation encryption according to an embodiment of the present invention.
Fig. 11 is a simulated error rate result graph according to an embodiment of the present invention.
Detailed Description
For a better understanding of the present solution, the method of the present invention is described in detail below with reference to the accompanying drawings.
The invention provides a safe transmission method based on a five-dimensional integer domain chaotic system, which is expressed by an iterative equation:
wherein x, y, z, w and t are chaotic state values of five dimensions, and the value is 0-2N1, N is the number of bits in a binary number representation, Sn、Un、Vn、LnAnd MnIs a unilateral infinite random sequence with the value of 0-2N-1; the resulting sequence diagram is shown in FIG. 1.
As shown in fig. 1, the transmission process of the safe transmission method based on the five-dimensional integer domain chaotic system is as follows:
at a transmitting end, firstly carrying out exclusive or encryption on originally transmitted data by using a generated x sequence, then mapping by using Quadrature Phase Shift Keying (QPSK), scrambling and encrypting the mapped data by using y and z sequences and carrying out interpolation encryption by using w and t sequences, and then transmitting the data into a satellite channel after passing through an RRC filter and a high-power amplifier (HPA); at a receiving end, the received signal is compensated firstly, then de-interpolation and descrambling are carried out, and then the unencrypted signal is recovered through XOR operation after QPSK demodulation.
In the above secure transmission method based on the five-dimensional integer domain chaotic system, the xor encryption equation is expressed as:
where Data is the original unencrypted input Data and x _ sequence is the resulting chaotic sequence. Data xor is QPSK mapped and then position scrambling encryption and interpolation encryption are performed.
In the secure transmission method based on the five-dimensional integer domain chaotic system, the scrambling encryption method comprises the following steps:
grouping data into N groups, wherein each group of data comprises 256 points, taking a generated y sequence as the number of groups to be scrambled, taking a generated z sequence as the position of the data to be scrambled in each group, and then scrambling, wherein N is M/256, M is the number of data, N which cannot be evenly divided by 256 is firstly added with 0 and then evenly divided.
The sequence without scrambling and encryption is shown in fig. 7, the sequence with scrambling and encryption is shown in fig. 8, and it can be seen from fig. 8 that the chaos sequence randomly controls the position of the scrambled data to complete the scrambling of the data, and the process is chaotic and unpredictable.
In the secure transmission method based on the five-dimensional integer domain chaotic system, the interpolation encryption method comprises the following steps:
and taking the value of the w sequence as the position for inserting Data in the Data _ scrambles, taking the value of the t sequence as the position for taking out the inserted Data in the Data _ scrambles, and then inserting the taken out Data into the position represented by the w sequence. The sequence which is not subjected to interpolation encryption is shown in fig. 9, the sequence which is subjected to interpolation encryption is shown in fig. 10, and the positions for generating interpolation and the positions for taking out interpolation data are controlled by chaotic sequences and have the advantages of disorder and unpredictability, so that the generated interpolation encryption effect is good.
The bit error rate result after simulation by the method of the present invention is shown in fig. 11, under the condition that the receiving end knows the correct key, the bit error rate of the solution is the same as the bit error rate of the original QPSK system, and the bit error rate gradually approaches 0 along with the increase of the signal-to-noise ratio; at the illegal receiver end, the error rate is kept about 0.744 under the condition that the correct key is not known. It can be seen from the bit error rate curve that the bit error rate of the chaotic system is high under the condition that a correct key is unknown, an illegal receiver cannot correctly decrypt the transmission information, and the chaotic system has high safety.
The invention uses the five-dimensional integer domain chaotic system to carry out the safe communication of the satellite system, and solves the short period phenomenon of chaotic dynamics degradation of the traditional chaotic system caused by limited computer precision while having lower complexity.
In conclusion, the method has better safety, simultaneously has lower calculation complexity, does not introduce other problems, can fundamentally solve the problem of chaotic dynamics degradation, and can be applied to a satellite communication system for the safe transmission of information.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: it is to be understood that modifications may be made to the technical solutions described in the foregoing embodiments, or equivalents may be substituted for some of the technical features thereof, but such modifications or substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.