Hidden wireless communication system and method applied to distributed sensitive information perception

Abstract

The invention discloses a concealed wireless communication system and method applied to distributed sensitive information perception, and a cooperative node is used for perceiving sensitive data information, coding the perceived sensitive data information based on a limited block length, and carrying out concealed communication with a destination node by using a distributed beam forming technology. The destination node decodes the sensitive data information after receiving the sensitive data information; meanwhile, the number of the cooperative nodes and the communication power are optimized with the purpose of maximizing the average effective hidden throughput of the system. Compared with traditional single-node sensing transmission during specific operation, the distributed beamforming method has the advantages that reliability and concealment of the system can be improved, the distributed beamforming method can be applied to complex scenes, and compared with a traditional covert communication system, the distributed beamforming technology provided by the distributed beamforming method can obtain higher covert throughput.

Description

Technical Field

[0001] The present invention belongs to the field of wireless network information security communication, and particularly relates to a covert wireless communication system and method applied to distributed sensitive information perception. Background Art

[0002] With the rapid development of wireless communication technology and the explosive growth of communication users, communication security issues have become increasingly prominent. In some important places, the collection and transmission of sensitive data are particularly important. In scenarios such as the vehicle-to-everything (V2X) network and the Internet of Things (IoT), distributed information perception can effectively improve the information perception and transmission capabilities as well as the security performance. During the transmission of sensitive information, information leakage is also a very thorny problem, which may cause irreparable losses. Traditional information security technologies use encryption algorithms and keys to encrypt information so that it cannot be deciphered by the enemy, thereby ensuring the security of the information content. However, on the one hand, with the significant improvement in computing power, even the most secure encryption technology may be cracked. On the other hand, how to avoid the communication behavior of legitimate parties from being detected by potential adversaries is a more critical security consideration.

[0003] In recent years, with the rise of covert wireless communication technology, new methods have been provided for solving communication security. Covert communication aims to hide the communication behavior of signals so that detectors can hardly detect the existence of communication behavior. Regarding the construction and performance optimization of covert wireless communication systems in various application scenarios, extensive research has also been carried out in the academic community. In actual communication scenarios, scholars have studied covert communication with the cooperation of other nodes.

[0004] The literature "Covert communication with a spectrum sharing relay in the finite blocklength regime," China Communications, vol. 20, no. 4, pp. 195-211, April 2023 analyzed the performance of increasing relay nodes for covert transmission and derived the effective covert rate from the relay to the destination node. The literature "Covert Wireless Communication With Artificial Noise Generation, IEEE Transactions on Wireless Communications, vol. 17, no. 11, pp. 7252-7267, Nov. 2018 studied the covert wireless communication scheme with the cooperation of multiple interfering nodes, and the results showed that the interfering signals can confuse the judgment of the detection node and effectively improve the covert performance. The above works have effectively demonstrated that cooperative nodes can improve the covertness of the system.

[0005] The literature "Research on Covert Communication Technology Based on Multi-User Collaboration. University of Electronic Science and Technology of Sichuan, 2023" studied the covert communication scenario under distributed multiple antennas and proved that constant-rate covert communication transmission can be achieved through distributed beamforming technology. However, its research is on the distributed beamforming covert wireless communication model under line-of-sight conditions, and there is currently a lack of in-depth research on more general fading channel scenarios. Therefore, the present invention studies a distributed sensitive information perception covert wireless communication method under Rayleigh fading channels. Summary of the Invention

[0006] In view of the above problems, the object of the present invention is to provide a covert wireless communication system and method for distributed sensitive information perception, which, based on finite blocklength coding, can enhance the communication concealment and increase the system reliability by using distributed beamforming technology.

[0007] The specific technical solution for achieving the object of the present invention is as follows:

[0008] A covert wireless communication system for distributed sensitive information perception, comprising cooperative nodes, a destination node, and a monitoring node;

[0009] Among them, the cooperative nodes are used to sense sensitive data information and send the sensed sensitive data information to the destination node;

[0010] The monitoring node is a possible monitoring party, which observes the wireless transmission environment to determine whether the cooperative nodes send sensitive data information to the destination node;

[0011] The destination node decodes the sensitive data information after receiving it;

[0012] The cooperative nodes, the destination node, and the monitoring node are all configured with single antennas and operate in a half-duplex mode.

[0013] Further, there are k cooperative nodes, and when there is sensitive data information to be sent, it is encoded into a finite-length data packet with the number of channel uses being N and then sent.

[0014] Further, when the cooperative node U r , r ∈ [1,..., k] senses sensitive data information and transmits it to the destination node, the transmission power P r of the covert transmission satisfies the communication concealment constraint to prevent being detected by the monitoring node:

[0015]

[0016] where d rw represents the distance between the cooperative node and the monitoring node; α represents the path loss factor; σ2 denotes the noise power; ε is an arbitrarily small real number representing the tolerance value of covert communication.

[0017] Furthermore, when the destination node decodes the received signal, the average effective covert throughput from the cooperative node to the destination node is:

[0018]

[0019] where R represents the amount of information transmitted per channel use, and E(δ) represents the average packet error rate of the system.

[0020] Furthermore, with the goal of maximizing the average effective covert throughput of the system, the number of cooperative nodes and the transmit power P of the cooperative nodes r are determined according to the following formula:

[0021]

[0022] The present invention also provides a covert wireless communication method applied to distributed sensitive information perception, including the following steps:

[0023] Step 1, the cooperative node perceives the privacy data information through radar;

[0024] Step 2, the cooperative node encodes the perceived privacy data packet and sends the privacy data packet to the destination node;

[0025] Step 3, the destination node decodes the received signal.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] In the specific operation of the solution of the present invention, multiple cooperative nodes perceive sensitive data information through radar, and then use beamforming technology to transmit the signal to the legitimate receiving node; compared with the traditional single-node perception and transmission, the present invention can improve the reliability and concealment of the system, and can be applied to complex scenarios. Moreover, compared with the traditional covert communication system, the distributed beamforming technology provided by the present invention can obtain higher covert throughput.

[0028] The following further describes the present invention in conjunction with specific embodiments. Description of the Drawings

[0029] Figure 1 is a schematic diagram of the covert wireless communication system model applied to distributed sensitive information perception of the present invention.

[0030] Figure 2 is a schematic diagram of the comparison of the average packet error rate of the system under different transmit power conditions in the embodiment of the present invention.

[0031] Figure 3 Schematic diagram of the comparison of the average effective covert throughput that can be achieved under different data packet lengths in the embodiments of the present invention. Detailed implementation manners

[0032] In order to clearly describe the technical solutions of the present invention and the achieved effects, the following combines the accompanying drawings of the present invention and specific embodiments to clearly illustrate the technical solutions of the present invention, so that those skilled in the art can implement the invention without creative labor. The structures shown in the drawings are not all of the actual structures but only a part of the actual structures. It should be noted that all other embodiments made by those of ordinary skill in the art without creative labor based on the embodiments of the present invention shall fall within the protection scope of the present invention.

[0033] Some of the following listed embodiments are only for better illustrating the present invention, but the content of the present invention is not limited to the applied embodiments. Therefore, those skilled in the art who make non-essential modifications to the implementation manners based on the above-mentioned invention content and apply them to other embodiments are still within the protection scope of the present invention. In addition, for the experimental methods without specific conditions marked in the following embodiments, they should be carried out according to the conventional or the conditions recommended by the manufacturer. If the expressions in the text are not specially explained, they are only used for distinction and do not have other meanings.

[0034] Embodiment

[0035] Combined with Figure 1 , a covert wireless communication system applied to distributed sensitive information perception, including cooperative nodes, destination nodes, and monitoring nodes;

[0036] Among them, the cooperative nodes are used to sense sensitive data information through radar and send the sensed sensitive data information to the destination nodes;

[0037] The monitoring nodes are potential monitoring parties, and judge whether the cooperative nodes send sensitive data information to the destination nodes by observing the wireless transmission environment;

[0038] After receiving the sensitive data information, the destination nodes decode it;

[0039] The cooperative nodes, destination nodes, and monitoring nodes are all configured with single antennas and operate in a half-duplex mode.

[0040] In the present application, there are k cooperative nodes. When there is sensitive data information to be sent, it is encoded into a finite-length data packet with a channel usage number of N for transmission. Based on k cooperative nodes for radar sensing and information transmission, compared with a single node, the reliability of the system is effectively improved;

[0041] When the collaborative node U r , r ∈ [1, ..., k], after sensing the sensitive data information, when transmitting it to the destination node, the transmission power P of the covert transmission r satisfies the communication concealment constraint to prevent being detected by the monitoring node:

[0042]

[0043] where f 1 (y W ) and f 0 (y W ) respectively represent the probability distributions of the observation samples of the monitoring node when the collaborative node has and does not have private data packets to send; represents the relative entropy between f 0 (y W ) and f 1 (y W ); E(·) represents taking the expectation; ε is an arbitrarily small real number, representing the tolerance value of covert communication. Using a mixture Gaussian model to approximate, the communication concealment constraint can be further derived as:

[0044]

[0045] Furthermore, the transmission power P r should satisfy:

[0046]

[0047] where d rw represents the distance between the collaborative node and the monitoring node; α represents the path loss factor; σ 2 represents the noise power; ε is an arbitrarily small real number, representing the tolerance value of covert communication.

[0048] Furthermore, when the destination node decodes the received signal, the received signal-to-noise ratio of the destination node can be expressed as:

[0049]

[0050] where, is the Gaussian Q function, and R represents the amount of information transmitted per channel use. The average packet error rate can be expressed as:

[0051]

[0052] Only when the data packet is correctly decoded does it contribute to the system's covert throughput. Then, the average effective covert throughput from the collaborative node to the destination node can be expressed as:

[0053]

[0054] Among them, R represents the amount of information transmitted per channel use, and E(δ) represents the average packet error rate of the system.

[0055] Furthermore, with the goal of maximizing the average effective covert throughput of the system, the number of cooperative nodes and the transmission power P of the cooperative nodes r are determined according to the following formula:

[0056]

[0057] The present invention also provides a covert wireless communication method applied to distributed sensitive information perception, including the following steps:

[0058] Step 1: The cooperative node senses the privacy data information through radar;

[0059] Step 2: The cooperative node encodes the sensed privacy data packet and sends the privacy data packet to the destination node;

[0060] When the cooperative node encodes the sensed privacy data packet, it encodes it into a finite-length data packet with the number of channel uses being N for transmission.

[0061] In addition, when the cooperative node sends the privacy data packet to the destination node, the transmission power P of the covert transmission r satisfies the communication covertness constraint:

[0062]

[0063] where d rw represents the distance between the cooperative node and the possible monitoring node; α represents the path loss factor; σ 2 represents the noise power; ε is an arbitrarily small real number, representing the tolerance value of the covert communication.

[0064] Step 3: The destination node decodes the received signal;

[0065] When decoding, the average effective covert throughput from the cooperative node to the destination node is:

[0066]

[0067] where R represents the amount of information transmitted per channel use, and E(δ) represents the average packet error rate of the system,

[0068] Therefore, with the goal of maximizing the average effective covert throughput of the system, the number of cooperative nodes and the transmission power P of the cooperative nodes in this method r are determined according to the following formula:

[0069]

[0070] The simulation of the variation of the average packet error rate with the number of cooperative nodes in the method of the present invention is as Figure 2 shown, where the amount of information transmitted per channel use is R = 0.3 nat / s / Hz, the coding length N = 100, and the distance between nodes is d rb = d rw = 150 m, the path loss factor α = 3, and the noise power The transmission powers of the cooperative nodes are respectively: P r = -22 dBm, -25 dBm, -28 dBm. It can be seen from Figure 2 that, secondly, E(δ) decreases with the increase of k, because increasing k means an increase in the total transmission power, the received signal-to-noise ratio at the destination node B increases, and thus the communication connection performance is improved; finally, when the transmission power increases, E(δ) decreases faster, which indicates that appropriately increasing the transmission power can reduce the average packet error rate at the destination node B. In summary, for a specific environment, jointly selecting the optimal k value and transmission power can effectively reduce the average connection interruption probability while meeting the covert constraint conditions.

[0071] The simulation of the variation of the average effective covert throughput with the number of cooperative nodes in the method of the present invention is as Figure 3 shown, where the amount of information transmitted per channel use is R = 0.3 nat / s / Hz, the coding length N = 100, and the distance between nodes is d rb = d rw = 150 m, the path loss factor α = 3, and the noise power The transmission power of the cooperative node is the maximum transmission power that satisfies the covert constraint. It can be seen from Figure 3 that the average effective covert throughput of the method of the present invention increases effectively significantly with the increase of the number of cooperative nodes.

[0072] The above embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A covert wireless communication system for distributed sensitive information perception, characterized in that: Includes collaboration nodes, destination nodes and monitoring nodes; The cooperation node is used to sense sensitive data information and send the sensed sensitive data information to the destination node; The monitoring node is a possible monitoring party, which observes the wireless transmission environment to determine whether the cooperative node sends sensitive data information to the destination node; The destination node receives the sensitive data information and decodes it; The cooperation node, the destination node and the monitoring node are all configured with a single antenna and work in a half-duplex mode.

2. The covert wireless communication system for distributed sensitive information perception according to claim 1, characterized in that: There are k cooperative nodes, and when sensitive data information needs to be sent, it is encoded into a finite-length data packet with a channel usage number of N for transmission.

3. The covert wireless communication system for distributed sensitive information perception according to claim 2, characterized in that: When the cooperation node U r ,r∈[1,...,k] After sensing the sensitive data information, when transmitting it to the destination node, the covert transmission power P r Satisfy communication concealment constraints to prevent being monitored by monitoring nodes: Among them, d rw represents the distance between the cooperation node and the monitoring node; α represents the path loss factor; σ 2 represents the noise power; ε is an arbitrarily small real number, which represents the tolerance value of covert communication.

4. The covert wireless communication system for distributed sensitive information perception according to claim 3 is characterized in that: When the destination node decodes the received signal, the average effective concealed throughput from the cooperation node to the destination node is: Where R represents the amount of information transmitted by each channel, and E(δ) represents the average packet error rate of the system.

5. The covert wireless communication system for distributed sensitive information perception according to claim 3, characterized in that: To maximize the average effective concealed throughput of the system, the number of cooperative nodes and the transmission power P of the cooperative nodes are r Determined according to the following formula:

6. A covert wireless communication method for distributed sensitive information perception, characterized in that: The following steps are involved: Step 1: The collaborative node senses the private data information through radar; Step 2: The cooperative node encodes the perceived privacy data packet and sends the privacy data packet to the destination node; Step 3: The destination node decodes the received signal.

7. The covert wireless communication method for distributed sensitive information perception according to claim 6, characterized in that: When the cooperative node in step 2 encodes the perceived privacy data packet, it encodes it into a finite-length data packet with a channel usage number of N for transmission.

8. The covert wireless communication method for distributed sensitive information perception according to claim 6, characterized in that: When the cooperative node sends a privacy data packet to the destination node, the transmission power P of the covert transmission is r Satisfy the communication concealment constraint: Among them, d rw represents the distance between the cooperation node and the possible monitoring node; α represents the path loss factor; σ 2 represents the noise power; ε is an arbitrarily small real number, which represents the tolerance value of covert communication.

9. The covert wireless communication method for distributed sensitive information perception according to claim 8, characterized in that: When the destination node decodes the received signal, the average effective concealed throughput from the cooperation node to the destination node is: Where R represents the amount of information transmitted by each channel, and E(δ) represents the average packet error rate of the system.

10. The covert wireless communication method for distributed sensitive information perception according to claim 9, characterized in that: To maximize the average effective concealed throughput of the system, the number of cooperative nodes and the transmission power P of the cooperative nodes are r Determined according to the following formula:

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