RSMA-NOMA-based power distribution method

Abstract

The invention discloses an RSMA-NOMA-based power distribution method, which comprises the following steps of: on one hand, absorbing multi-user interference through a public message by utilizing the advantages of an RSMA technology, and converting part of interference into an effective signal; and on the other hand, the same frequency interference of private information of part of users can be reduced by using the NOMA technology. However, as the power of downlink data transmission of a base station is limited, how to allocate the data to a plurality of users sharing the same frequency point at limited power and low complexity based on the RSMA-NOMA technology is a key problem needing to be solved in the invention. Based on the above problem, the invention provides a power distribution method based on RSMA-NOMA, the power of the public rate, the power of the private rate of the user and the optimization problem of the leader jointly form a game model, and an optimal solution is obtained through a convex optimization theory. The invention aims to provide a unique and low-complexity solution. The method physically accords with the scene of practical application and can be effectively applied to engineering practice.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of multiple access technology, and in particular to a power allocation method based on RSMA-NOMA. BACKGROUND

[0002] Rate-Splitting Multiple Access (RSMA) technology is one of the key multiple access technologies in the evolution from 5G to 6G. As the demand for spectral efficiency, user fairness, and system capacity of mobile communication systems continues to rise, traditional Orthogonal Multiple Access (OMA) and Non-Orthogonal Multiple Access (NOMA) technologies face challenges such as spectrum resource scarcity and complex interference management. In this context, RSMA achieves more efficient spectrum utilization and flexible interference management by splitting user data into public and private parts, combining Superposition Coding and Successive Interference Cancellation (SIC) techniques. RSMA can dynamically adjust the ratio of public and private streams to adapt to different user channel conditions, significantly improving system performance in high-load and strong-interference scenarios. Its technical advantages include higher spectral efficiency, stronger user fairness, and robustness to incomplete channel state information, making it one of the core technologies for supporting massive connectivity and ultra-low latency communication in future 6G networks. The present application focuses on the power allocation method based on RSMA-NOMA, which combines the power of public rate, the power of user's private rate, and the optimization problem of the leader into a game model, and obtains the optimal solution through convex optimization theory. The present application aims to provide a unique and low-complexity solution that is physically consistent with real-world application scenarios and can be effectively applied to engineering practice. SUMMARY

[0003] The present application discloses a power allocation method based on RSMA-NOMA, which includes the following steps:

[0004] Step 1, collect parameters: communication bandwidth , receiver noise , user channel gain and , and the power value P of RSMA-NOMA cluster;

[0005] Step 2, calculate , solve the roots and of the equation group and ;

[0006] Step 3, if and and and 4 The optimal power value supporting the common rate based on the RSMA-NOMA technology is

[0007]

[0008] The optimal power value supporting the private rate of user 1 based on the RSMA-NOMA technology is

[0009]

[0010] The optimal power value supporting the private rate of user 2 based on the RSMA-NOMA technology is

[0011]

[0012] Preferably, in order to reduce the interference between users in the private information transmission, the NOMA technology is adopted. That is, in the RSMA-NOMA technology, on the one hand, the advantages of the RSMA technology are used to absorb the multi-user interference through the common message, and part of the interference is converted into an effective signal; on the other hand, the advantages of the NOMA technology are used to reduce the same-frequency interference of the private information of part of the users through the SIC technology.

[0013] Preferably, the optimization problem of the common information based on the RSMA technology is modeled as

[0014]

[0015] The optimization problem of the private information of user 1 based on the NOMA technology is modeled as

[0016]

[0017] The optimization problem of the private information of user 2 based on the NOMA technology is modeled as

[0018]

[0019] Preferably, in step 2, the game optimal pricing of the leader is , and the roots and of the equation group and ;

[0020] Preferably, in step 3, when , and , and , and , the optimal power value supporting the common rate based on the RSMA-NOMA technology is

[0021]

[0022] The optimal power value for supporting user 1's private rate based on RSMA-NOMA technology is

[0023]

[0024] The optimal power value for supporting user 2's private rate based on RSMA-NOMA technology is

[0025]

[0026] The beneficial effects of this invention are as follows: This invention discloses a power allocation method based on RSMA-NOMA. In traditional RSMA, multi-user interference is absorbed through common messages, converting some interference into effective signals. However, during the transmission of private information, each user suffers from co-channel interference from other users. In this invention, NOMA technology is adopted to reduce interference between users during the transmission of private information. That is, in the proposed RSMA-NOMA technology, on the one hand, the advantages of RSMA technology are utilized to absorb multi-user interference through common messages, converting some interference into effective signals; on the other hand, the advantages of NOMA technology are utilized to reduce co-channel interference of some users' private information through SIC technology. However, since the downlink data transmission power of the base station is limited, how to allocate the limited power based on RSMA-NOMA technology with low complexity to multiple users sharing the same frequency point is the key problem that this invention needs to solve. Based on the above problem, this invention proposes a power allocation method based on RSMA-NOMA, which combines the power of the common rate, the power of the user's private rate, and the leader optimization problem into a game model, and obtains the optimal solution through convex optimization theory. This invention aims to provide a unique and low-complexity solution. It physically conforms to real-world application scenarios and can be effectively applied to engineering practice. Attached Figure Description

[0027] Figure 1 This is a flowchart of a power allocation method based on RSMA-NOMA proposed in this invention. Detailed Implementation

[0028] A power allocation method based on RSMA-NOMA includes the following steps:

[0029] Step 1: Collect parameters: Communication bandwidth Receiver noise User channel gain and And the power value P of the RSMA-NOMA cluster;

[0030] Step 2, Calculation Solve the system of equations and The root and ;

[0031] Step 3, if and and And 4 The optimal power value for supporting common rates based on RSMA-NOMA technology is...

[0032]

[0033] The optimal power value for supporting user 1's private rate based on RSMA-NOMA technology is

[0034]

[0035] The optimal power value for supporting user 2's private rate based on RSMA-NOMA technology is

[0036]

[0037] To reduce interference between users during the transmission of private information, NOMA technology is adopted. Specifically, in the proposed RSMA-NOMA technology, on the one hand, the advantages of RSMA technology are utilized to absorb multi-user interference through public messages, converting some interference into effective signals; on the other hand, the advantages of NOMA technology are utilized to reduce co-channel interference of some users' private information through SIC technology.

[0038] Modeling the optimization problem of public information based on RSMA technology as follows

[0039]

[0040] Modeling the optimization problem for user 1's private information based on NOMA technology as follows:

[0041]

[0042] Modeling the optimization problem for user 2's private information based on NOMA technology as follows:

[0043]

[0044] In step 2, the leader's optimal game pricing is as follows: and the system of equations and The root and ;

[0045] In step 3, when and and And 4 At that time, the optimal power value for supporting common rates based on RSMA-NOMA technology is

[0046]

[0047] The optimal power value for supporting user 1's private rate based on RSMA-NOMA technology is

[0048]

[0049] The optimal power value for supporting user 2's private rate based on RSMA-NOMA technology is

[0050]

[0051] Combination Figure 1 As shown, the design of the present invention will be further analyzed and described in detail.

[0052] The advantages of the RSMA (Rate-Splitting Multiple Access) technology studied in this invention are: 1) High spectral efficiency, allowing multiple users to share the same time-frequency resources, with resource utilization significantly higher than OMA; 2) Absorbing multi-user interference through common messages, converting some interference into effective signals (superior to NOMA (Non-Orthogonal Multiple Access)); 3) Flexible adjustment of the power ratio of common / private messages to adapt to channel changes and interference fluctuations; 4) Simultaneous service of high-priority (private messages) and low-priority (common messages) data streams. The disadvantages are: 1) Serial interference cancellation (SIC) is required to decode common and private messages, increasing hardware complexity; 2) Dynamic resource allocation (power, precoding) involves non-convex optimization, resulting in high algorithm complexity.

[0053] In traditional RSMA, it is assumed that there are a total With multiple users existing simultaneously, without loss of generality, assume the channel gain from the base station to the user is... Sort in ascending order, that is Based on RSMA technology, it is known that the user with the lowest channel gain determines the upper limit of the common rate; therefore, the common rate can be obtained as follows:

[0054]

[0055] in, For communication bandwidth, For receiver noise, This refers to the base station's transmission power for public information. This represents the total transmit power of the base station for private data streams.

[0056] Meanwhile, users The private rate obtained based on RSMA is

[0057]

[0058] in, For base stations for users The transmission power of private information This represents the total transmission power of the base station for the private information of the remaining users.

[0059] As can be seen from the above, in RSMA, although multi-user interference can be absorbed through public messages and some interference can be converted into effective signals, each user will suffer from co-channel interference from other users during the transmission of private information.

[0060] Therefore, in this invention, NOMA technology is employed to reduce interference between users during the transmission of private information. Specifically, in the proposed RSMA-NOMA technology, on the one hand, the advantages of RSMA technology are utilized to absorb multi-user interference through common messages, converting some interference into effective signals; on the other hand, the advantages of NOMA technology are utilized to reduce co-channel interference of some users' private information through SIC technology. However, since the downlink data transmission power of the base station is limited, how to allocate the limited power with low complexity to multiple users sharing the same frequency point based on RSMA-NOMA technology is a key problem that this invention needs to solve.

[0061] To reduce the additional complexity and decoding latency caused by the use of SICs on user receivers, each RSMA-NOMA cluster is limited to containing two users in this invention. (If there are multiple users in the network, these users can be divided into multiple RSMA-NOMA clusters for communication, and the downlink total power of the base station in each RSMA-NOMA cluster is the average of its total power).

[0062] In RSMA-NOMA, two users compete for limited power resources, and both public and private rates need to be considered. Therefore, in this invention, the optimization problem for public information based on RSMA technology is modeled as follows:

[0063]

[0064] in, This represents the price a leader sets for a unit of power in a resource game based on RSMA (Resources, Power, and Information) technology. For common rates based on RSMA technology (about (a function whose value varies with) It increases with the increase in size, but the growth rate slows down; There is a corresponding cost to obtaining power supporting the common rate based on RSMA technology. Therefore, in the game, the more power supporting the common rate purchased based on RSMA technology, the greater the common rate obtained, but the greater the cost.

[0065] In this invention, the optimization problem for user 1's private information based on NOMA technology is modeled as follows:

[0066]

[0067] in, This represents the price per unit of power that the leader sets for user 1's private information based on NOMA technology in a resource game. For User 1 private rate based on NOMA technology (about (a function whose value varies with) It increases with the increase in size, but the growth rate slows down; There is a corresponding cost to obtaining power to support User 1's private rate based on NOMA technology. Therefore, in the game, the more power that User 1 purchases to support its private rate based on NOMA technology, the greater the public rate it obtains, but the greater the cost it pays.

[0068] Similarly, the optimization problem for user 2's private information based on NOMA technology is modeled as follows:

[0069]

[0070] in, This represents the price per unit of power that the leader sets for user 2's private information based on NOMA technology in a resource game. For User 2 private rates based on NOMA technology (about (a function whose value varies with) It increases with the increase in size, but the growth rate slows down; There is a corresponding cost to acquiring power to support User 2's private rate based on NOMA technology. Therefore, in the game, the more power purchased to support User 2's private rate based on NOMA technology, the greater the public rate obtained, but the greater the cost.

[0071] The leader (base station) sells limited power to multiple competing public rates, user 1's private rate, and user 2's private rate for transmitting their respective messages. Therefore, the optimization problem for the leader in this game is modeled as follows:

[0072]

[0073] st

[0074] in, The power value allocated to this RSMA-NOMA cluster; objective function This represents the total revenue generated by a base station selling limited power resources to multiple competing public rates, user 1's private rate, and user 2's private rate for transmitting their respective messages; the constraint is that the total power sold by the base station is less than or equal to the power value allocated to the RSMA-NOMA cluster.

[0075] The aforementioned public rate, user 1's private rate, user 2's private rate, and the leader's optimization problem together constitute a game theory model. By having both sides engage in game actions according to certain rules, a final equilibrium can be obtained. The optimal solution can be obtained using convex optimization theory; the steps are detailed below:

[0076] The objective function for optimizing user 2's private rate in the game relationship is applied to the optimization variables. Taking the first-order partial derivative, we can obtain

[0077]

[0078] in, Indicates when hour, ;otherwise, .

[0079] Therefore, when At that time,

[0080]

[0081] The objective function for optimizing user 1's private rate in the game relationship is applied to the optimization variables. Taking the first-order partial derivative, we can obtain

[0082]

[0083] Therefore, when and ,have

[0084]

[0085] The objective function for optimizing the common rate in the game relationship is applied to the optimization variables. Taking the first-order partial derivative, we can obtain

[0086]

[0087] Therefore, when and and ,have

[0088]

[0089] In game theory, a leader can pursue higher gains by selling all of their power values; therefore, when and and Sometimes,

[0090]

[0091] achievable

[0092]

[0093] Therefore, there is

[0094]

[0095] Therefore, when and and And 4 At that time, the optimization problem of the leader (base station) becomes

[0096]

[0097] The above is a convex optimization problem, and the optimal solution can be obtained through convex optimization theory. and Satisfy the following two equations

[0098]

[0099] and

[0100]

[0101] Based on the above conclusions, a power allocation method based on RSMA-NOMA under a game theory mechanism is presented below:

[0102] Step 1: Collect parameters: Communication bandwidth Receiver noise User channel gain and And the power value P of the RSMA-NOMA cluster;

[0103] Step 2, Calculation Solve the system of equations and The root and ;

[0104] Step 3, if and and And 4 The optimal power value for supporting common rates based on RSMA-NOMA technology is...

[0105]

[0106] The optimal power value for supporting user 1's private rate based on RSMA-NOMA technology is

[0107]

[0108] The optimal power value for supporting user 2's private rate based on RSMA-NOMA technology is

[0109] .

Claims

1. A power allocation method based on RSMA-NOMA, characterized in that, Includes the following steps: Step 1: Collect parameters: Communication bandwidth Receiver noise User channel gain and And the power value P of the RSMA-NOMA cluster; Step 2, Calculation Solve the system of equations and The root and ; Step 3, if and and And 4 The optimal power value for supporting common rates based on RSMA-NOMA technology is... The optimal power value for supporting user 1's private rate based on RSMA-NOMA technology is The optimal power value for supporting user 2's private rate based on RSMA-NOMA technology is 2. The power allocation method based on RSMA-NOMA according to claim 1, characterized in that, To reduce interference between users during the transmission of private information, NOMA technology is employed. Specifically, in the proposed RSMA-NOMA technology, on the one hand, the advantages of RSMA are utilized to absorb multi-user interference through public messages, converting some interference into effective signals; on the other hand, the advantages of NOMA are utilized to reduce co-channel interference of some users' private information through SIC technology.

3. The power allocation method based on RSMA-NOMA according to claim 1, characterized in that, Modeling the optimization problem of public information based on RSMA technology as follows in, This represents the price a leader sets for a unit of power in a resource game based on RSMA (Resources, Power, and Information) technology. Modeling the optimization problem for user 1's private information based on NOMA technology as follows: in, This represents the price per unit of power that the leader sets for user 1's private information based on NOMA technology in a resource game. Modeling the optimization problem for user 2's private information based on NOMA technology as follows: in, This represents the price per unit of power that the leader sets for the private information of User 2 based on NOMA technology in a resource game.

4. The power allocation method based on RSMA-NOMA according to claim 1, characterized in that, In step 2, the leader's optimal game pricing is as follows: and the system of equations and The root and .

5. The power allocation method based on RSMA-NOMA according to claim 1, characterized in that, In step 3, when and and And 4 At that time, the optimal power value for supporting common rates based on RSMA-NOMA technology is The optimal power value for supporting user 1's private rate based on RSMA-NOMA technology is The optimal power value for supporting user 2's private rate based on RSMA-NOMA technology is

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