A rate division multiple access secrecy method combining antenna selection and digital network coding

Abstract

The application discloses a rate division multiple access security method combining antenna selection and digital network coding. In a first time slot, a source user divides a signal into a public stream and a private stream and sends a multiple access signal to a relay. The relay selects an optimal antenna to send artificial noise according to instantaneous channel state information between the relay and trusted users, and selects an optimal antenna to receive a signal sent by the source user according to instantaneous channel state information between the source user and the remaining antennas of the relay. In addition, the trusted users generate artificial noise to interfere with untrusted users. In a second time slot, the relay uses network coding to combine signals of the trusted users whose signals are successfully decoded in the first time slot and artificial noise generated by the relay, and then combines the signals with signals of the untrusted users to form a new multiple access signal and forwards the new multiple access signal. The application combines antenna selection and digital network coding, thereby ensuring security of communication between the source user and the trusted users and improving transmission reliability between the source user and the untrusted users.

Description

Technical Field

[0001] This invention relates to a communication transmission method, and more particularly to an RSMA communication physical layer security method. Background Technology

[0002] The surge in wireless communication services has led to increasingly scarce spectrum resources. Rate-splitting multiple access (RSMA), with its flexible interference management capabilities, has become crucial for improving spectrum efficiency and system robustness. RSMA achieves more flexible interference management than traditional orthogonal multiple access (OMA) and non-orthogonal multiple access (NOMA) by splitting user messages into public and private components and transmitting them in superimposed form. This makes RSMA a key technology for further improving spectrum efficiency and system robustness in future wireless communication networks. Furthermore, RSMA can exhibit superior transmission rate performance compared to NOMA under various channel correlations and load conditions by adjusting the power allocation between public and private flows.

[0003] However, the open nature of wireless communication makes it highly vulnerable to eavesdropping attacks by unauthorized users. Physical layer security technologies can leverage the physical characteristics of wireless signals and channels to fundamentally ensure the wireless security performance of RSMA communication. In particular, artificial noise technology reduces the eavesdropping capabilities of untrusted users by sending interference signals, thereby improving system security. However, traditional solutions often sacrifice the transmission reliability of untrusted users while enhancing security. How to balance security gains with user fairness has become a pressing contradiction in current RSMA system design. Summary of the Invention

[0004] Purpose of the invention: To address the aforementioned existing technologies, this invention proposes a rate division multiple access (RDBMI) encryption method that combines antenna selection and digital network coding to ensure the security of communication between the source user and trusted users, while simultaneously improving the transmission reliability between the source user and untrusted users.

[0005] Technical Solution: A rate division multiple access (RDBMI) encryption method combining antenna selection and digital network coding, applied to a RDBMI wireless communication scenario, the scenario including a source user, a relay equipped with multiple antennas, a full-duplex trusted user, and an untrusted user, the method comprising: in a first time slot, the source user transmits a multiple access signal. ,in This indicates a common stream signal sent to the user. and These represent signals sent to trusted users and untrusted users, respectively. , and These represent the power allocation coefficients for the common flow signal, trusted user signal, and untrusted user signal, respectively; the relay selects the optimal antenna to generate artificial noise. Trusted users generate artificial noise. Additionally, the relay selects the optimal antenna from the remaining antennas to receive the signal transmitted by the source user. The relay decodes the received signal.

[0006] In the second time slot, the relay decodes the trusted user signal from the first time slot. Artificial noise generated by the first time slot relay The signal is then merged using network coding, and subsequently combined with untrusted user signals. Constructing new multiple access signals Simultaneously, the optimal antenna is selected to forward the new multiple access signal; then, the interruption probability and eavesdropping probability of trusted users, as well as the interruption probability of untrusted users, are calculated based on the received signal-to-interference-plus-noise ratio.

[0007] Beneficial Effects: In situations where existing RSMA systems lack user fairness, this invention proposes a rate division multiple access (RDM) encryption method combining antenna selection and digital network coding. This method ensures the security of communication between the source user and trusted users while improving the transmission reliability between the source user and untrusted users. Specifically, the entire communication process can be divided into two time slots. In the first time slot, the source user sends an RSMA signal to the relay, while the relay uses its optimal antenna to send artificial noise to interfere with the untrusted user. It also selects the optimal antenna from the remaining antennas to receive the RSMA signal sent by the source user. Additionally, the trusted user generates artificial noise to interfere with the untrusted user. In the second time slot, the relay uses network coding to combine the successfully decoded trusted user signal from the first time slot with the artificial noise generated by the relay. This combined signal and the untrusted user signal are then used to construct a new multiple access signal for forwarding. Finally, the outage probability and eavesdropping probability of the trusted user, as well as the outage probability of the untrusted user, are calculated based on the received signal-to-interference-plus-noise ratio (SINR).

[0008] Compared with existing technologies, this method has the following specific advantages:

[0009] 1. This invention proposes an optimized scheme that balances the security of trusted users with the transmission reliability of untrusted users by combining antenna selection and digital network coding, thereby ensuring user fairness in the RSMA system.

[0010] 2. By leveraging RSMA technology to significantly enhance spectrum utilization and system robustness, and further combining it with relay cooperation mechanisms, the aim is to effectively expand the coverage boundaries of wireless communication and achieve signal transmission over longer distances.

[0011] 3. It not only ensures the security of communication between the source user and the trusted user, but also improves the transmission reliability between the source user and the untrusted user. Attached Figure Description

[0012] Figure 1 A model diagram illustrating the application scenario of the method of this invention;

[0013] Figure 2 This is a flowchart of the method of the present invention;

[0014] Figure 3 This is a comparison chart of the interruption probability and eavesdropping probability of trusted and untrusted users for the present invention and the comparative scheme.

[0015] Figure 4 This is a comparison chart showing the compromise performance of the present invention and the comparative scheme in terms of security and reliability for trusted and untrusted users. Detailed Implementation

[0016] The invention will now be further explained with reference to the accompanying drawings.

[0017] A rate division multiple access (RDBMA) encryption method combining antenna selection and digital network coding is applied to RSMA-assisted cooperative communication scenarios, such as... Figure 1 As shown, the scenario includes a source user, a relay with 6 antennas, a full-duplex trusted user, and a single-antenna untrusted user.

[0018] like Figure 2 As shown, the specific steps of the confidentiality method of the present invention are as follows: In the first time slot, the source user sends a multiple access signal. ,in This indicates a common stream signal sent to the user. and These represent signals sent to trusted users and untrusted users, respectively. , and These represent the power allocation coefficients for the common flow signal, trusted user signal, and untrusted user signal, respectively; the relay selects the optimal antenna to generate artificial noise. Trusted users generate artificial noise. Additionally, the relay selects the optimal antenna from the remaining antennas to receive the signal transmitted by the source user. The relay decodes the received signal.

[0019] In the second time slot, the relay decodes the trusted user signal from the first time slot. Artificial noise generated by the first time slot relay This signal is then merged through network coding and subsequently combined with untrusted user signals. Constructing new multiple access signals Simultaneously, the optimal antenna is selected to forward the new multiple access signal; then, the interruption probability and eavesdropping probability of trusted users, as well as the interruption probability of untrusted users, are calculated based on the received signal-to-interference-plus-noise ratio.

[0020] Specifically, in the first time slot, the relay uses the following transmit antenna selection algorithm: The receiving antenna selection algorithm is as follows: ,in This represents the channel gain coefficient from the j-th antenna of the relay to the trusted user. Let represent the channel gain coefficient from the source user to the t-th antenna of the relay. This represents the set of antennas at the relay point. This represents the set of antennas remaining after removing the i-th antenna at the relay point; therefore, the signal received by the relay is:

[0021] ;

[0022] in This represents the channel gain coefficient between the source user and the relay's receiving antenna. This represents the channel gain coefficient between the trusted user and the relay receiving antenna. This represents the self-interference channel gain coefficient of the relay. and The transmit power of the source user and the trusted user are respectively. The noise power at the relay receiving antenna is... Additive white Gaussian noise with a mean of 0.

[0023] Relay decoding signal , and The corresponding signal-to-interference-plus-noise ratios are as follows: ;

[0024] ;

[0025] ;

[0026] in This indicates self-interference at the relay node. This is the threshold for interference cancellation.

[0027] Trusted users and untrusted users The signals received in the first time slot are as follows:

[0028] ;

[0029] ;

[0030] in and These represent the relay optimal antenna to the trusted user. and untrusted users The channel gain coefficient, and These represent the self-interference channel gain coefficient of the trusted user and the channel gain coefficient from the trusted user to the untrusted user, respectively. Indicates a trusted user The noise power at the location is Additive Gaussian noise with a mean of 0; Indicates untrusted user The noise power at the location is Additive Gaussian noise with a mean of 0.

[0031] Therefore, trusted users and untrusted users decode signals. The signal-to-interference-plus-noise ratios are as follows:

[0032] ;

[0033] ;

[0034] in This indicates self-interference at the trusted user location in the first time slot. This indicates the transmission power of the first time slot of the relay.

[0035] In the second time slot, the relay employs the optimal antenna selection algorithm. Send encoded multiple access signal For trusted users and untrusted users, among which Let be the channel gain coefficient from the j-th antenna of the second time slot relay to the trusted user; therefore, the received signals at the trusted user and the untrusted user are respectively:

[0036] ;

[0037] ;

[0038] in and These represent the optimal antenna to trusted user relayed in the second time slot, respectively. and untrusted users Channel gain coefficient between This indicates the transmission power of the second time slot of the relay.

[0039] Trusted User Decoding and The signal-to-interference-plus-noise ratios are as follows:

[0040] ;

[0041] ;

[0042] Untrusted user decoding signal , and The signal-to-interference-plus-noise ratios are as follows:

[0043] ;

[0044] ;

[0045] ;

[0046] Therefore, the probability of interruption and the probability of eavesdropping for a trusted user are respectively:

[0047] ,

[0048] ;

[0049] in, This indicates that an untrusted user is eavesdropping on signals. The probability, , , and They represent signals respectively. , and The decoding threshold and the security threshold of the confidential signal, Indicates decoding interference signal The threshold; the interruption probability of untrusted users is:

[0050] .

[0051] The following is a simulation using Matlab on a computer to realize the interruption probability of trusted and untrusted users, as well as the eavesdropping probability of trusted users. In the simulation, it is assumed that the wireless channels are independent and follow Rayleigh fading. and They respectively follow the mean of and The exponential distribution, where and .set up , , , , , , dB , , , , , and Furthermore, the noise power at each node is the same. .

[0052] Figure 3 The graph shows the interruption probability and eavesdropping probability of trusted and untrusted users when the relay antenna N=6. Figure 3 This indicates that increasing the transmission power can improve the transmission reliability of a rate division multiple access (RDBMI) communication system, but it reduces the system's transmission security, demonstrating that security and reliability are mutually restrictive. Furthermore, the trusted user in this invention achieves superior security performance compared to traditional artificial noise schemes, while its reliability is almost identical. For untrusted users, the artificial noise scheme proposed in this invention exhibits significantly better reliability than traditional artificial noise schemes.

[0053] Figure 4 The graph shows the security and reliability trade-off between trusted users and traditional artificial noise schemes. For trusted users, the proposed artificial noise scheme demonstrates a better security and reliability trade-off performance than traditional artificial noise schemes. Specifically, given a certain system reliability, the eavesdropping probability of the proposed artificial noise scheme is significantly lower than that of traditional artificial noise schemes, indicating that the proposed artificial noise scheme improves transmission security. Furthermore, Figure 4 This indicates that as the number of antennas increases, the security and reliability of trusted users also increases.

[0054] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A rate division multiple access (RDBMI) encryption method combining antenna selection and digital network coding, characterized in that, The method is applied to a rate-division multiple access (RDBMI) wireless communication scenario, which includes a source user, a relay equipped with multiple antennas, a full-duplex trusted user, and an untrusted user. The method includes: in a first time slot, the source user transmits a multiple access signal. ,in This indicates a common stream signal sent to the user. and These represent signals sent to trusted users and untrusted users, respectively. , and These represent the power allocation coefficients for the common flow signal, trusted user signal, and untrusted user signal, respectively; the relay selects the optimal antenna to generate artificial noise. Trusted users generate artificial noise. Additionally, the relay selects the optimal antenna from the remaining antennas to receive the signal transmitted by the source user. The relay decodes the received signal. In the second time slot, the relay decodes the trusted user signal from the first time slot. Artificial noise generated by the first time slot relay The signal is then merged using network coding, and subsequently combined with untrusted user signals. Constructing new multiple access signals Simultaneously, the optimal antenna is selected to forward the new multiple access signal; then, the interruption probability and eavesdropping probability of trusted users, as well as the interruption probability of untrusted users, are calculated based on the received signal-to-interference-plus-noise ratio.

2. The rate division multiple access encryption method based on joint antenna selection and digital network coding according to claim 1, characterized in that, In the first time slot, the relay uses the following transmit antenna selection algorithm: The receiving antenna selection algorithm is as follows: ,in This represents the channel gain coefficient from the j-th antenna of the relay to the trusted user. Let represent the channel gain coefficient from the source user to the t-th antenna of the relay. This represents the set of antennas at the relay point. This represents the set of antennas remaining after removing the i-th antenna at the relay point.

3. The rate division multiple access encryption method based on joint antenna selection and digital network coding according to claim 1 or 2, characterized in that, In the first time slot, the signal received by the relay is: ； in This represents the channel gain coefficient between the source user and the relay's receiving antenna. This represents the channel gain coefficient between the trusted user and the relay receiving antenna. This represents the self-interference channel gain coefficient of the relay. and The transmit power of the source user and the trusted user are respectively. The noise power at the relay receiving antenna is... Additive white Gaussian noise with a mean of 0; Relay decoding signal , and The corresponding signal-to-interference-plus-noise ratios are as follows: ， ， ； in This indicates self-interference at the relay node. This is the threshold for interference cancellation.

4. The rate division multiple access encryption method based on joint antenna selection and digital network coding according to claim 3, characterized in that, Trusted users and untrusted users The signals received in the first time slot are as follows: ， ； in and These represent the relay optimal antenna to the trusted user. and untrusted users The channel gain coefficient, and These represent the self-interference channel gain coefficient of the trusted user and the channel gain coefficient from the trusted user to the untrusted user, respectively. Indicates a trusted user The noise power at the location is Additive Gaussian noise with a mean of 0; Indicates untrusted user The noise power at the location is Additive Gaussian noise with a mean of 0; Trusted users and untrusted users decode signals The signal-to-interference-plus-noise ratios are as follows: ， ； in This indicates self-interference at the trusted user location in the first time slot. This indicates the transmission power of the first time slot of the relay.

5. The rate division multiple access encryption method based on joint antenna selection and digital network coding according to claim 4, characterized in that, In the second time slot, the relay employs the optimal antenna selection algorithm. Send encoded multiple access signal For trusted users and untrusted users, among which is the channel gain coefficient from the j-th antenna of the second time slot relay to the trusted user.

6. The rate division multiple access encryption method based on joint antenna selection and digital network coding according to claim 5, characterized in that, In the second time slot, the signals received at the trusted user and the untrusted user are as follows: ， ； in and These represent the optimal antenna to trusted user relayed in the second time slot, respectively. and untrusted users Channel gain coefficient between This indicates the transmission power of the second time slot of the relay; Trusted User Decoding and The signal-to-interference-plus-noise ratios are as follows: ， ； Untrusted user decoding signal , and The signal-to-interference-plus-noise ratios are as follows: ， ， 。 7. The rate division multiple access encryption method based on joint antenna selection and digital network coding according to claim 6, characterized in that, The probability of interruption for a trusted user is: ； The probability of a trusted user being eavesdropped on is: ； in, , , and They represent signals respectively. , and The decoding threshold and the security threshold of the confidential signal, Indicates decoding interference signal The threshold; the interruption probability of untrusted users is: 。

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