A Frequency Division Hybrid Multiple Access Cellular Access Network Planning Method

Abstract

The present invention discloses a frequency division hybrid multiple access cellular access network planning method, comprising the following steps: (1) constructing a hybrid multiple access model for a wireless communication system including a base station configured with M antennas and two single-antenna users; (2) constructing a downlink optimization transmission model with multiple constraints aiming at minimizing the system energy consumption; (3) solving the multi-objective energy minimization problem by using a method of continuous resource allocation interaction iteration; (4) performing access according to the obtained optimal power allocation solution; the present invention utilizes the advantages of orthogonal and non-orthogonal multiple access methods, and can reduce interference and improve the coverage range while improving the throughput by sharing resource elements.

Description

Technical Field

[0001] The present invention relates to the technical field of communication engineering, and particularly to a frequency division hybrid multiple access cellular access network planning method. Background Art

[0002] In today's communication environment, with the rapid development of the mobile Internet, the number of mobile devices and data traffic have increased sharply. 5G networks and their subsequent technologies require more efficient spectrum utilization to cope with the explosive growth of bandwidth demand. In traditional orthogonal multiple access technologies (such as TDMA, FDMA, OFDMA, etc.), different users are assigned to different resource blocks (such as time, frequency, or orthogonal codes) to avoid mutual interference. However, the spectrum utilization of this method is limited, and the demand for high-speed growing data and large-scale connections has gradually emerged. Non-orthogonal multiple access technologies can improve spectrum efficiency and support large-scale user connections. Non-orthogonal multiple access technologies improve throughput, but they introduce additional interference, thus reducing the coverage range. Summary of the Invention

[0003] Object of the Invention: The object of the present invention is to provide a frequency division hybrid multiple access cellular access network planning method, which optimizes the frequency band allocation coefficient and power spectral density allocation coefficient by constructing a hybrid multiple access model, designing a downlink optimization transmission model with multiple constraints, and solving the multi-objective energy minimization problem, so as to maximize the use of limited spectrum resources to overcome the respective disadvantages of orthogonal and non-orthogonal multiple access technologies.

[0004] Technical Solution: A frequency division hybrid multiple access cellular access network planning method according to the present invention includes the following steps:

[0005] (1) For a wireless communication system including a base station with M configured antennas and two users with single antennas, construct a hybrid multiple access model;

[0006] (2) With the goal of minimizing the system energy consumption, construct a downlink optimization transmission model under multiple constraints;

[0007] (3) Use the method of continuous resource allocation interactive iteration to solve the multi-objective energy minimization problem;

[0008] (4) Perform access according to the obtained optimal power allocation solution.

[0009] Further, in step (1), the hybrid multiple access model is specifically as follows: Use a downlink cellular network, and a base station serves two users in each resource element RE through frequency division hybrid multiple access, namely and , and mix and transmit the signals of two users with different powers;

[0010] Sort two UEs according to the channel strength metric: According to the base station at coordinate system 0, sort the UEs according to the connection distance R between it and the UEs uniformly distributed within a disk with as the radius; call the strong terminal with a shorter link distance , and call the weak terminal with a longer link distance ; in the frequency division hybrid multiple access, the frequency band resource units are divided into three regions, namely , and , and share the proportion of the REs in the region, which is represented by , and use to represent the proportion of the REs in the region that only can enter, where ; then represents the proportion of the bandwidth of , and represents the non-overlapping part; the base station provides OMA services in the region of user and the region of , and provides NOMA services in the region where and overlap. Overlapping region.

[0011] Furthermore, in step (1), the hybrid multiple access model formula is as follows: In different frequency band regions, namely , and , the terminal receives the following signals:

[0012] ;

[0013] ;

[0014] ;

[0015] ;

[0016] Among them, represents the signal received in the region, and represents the signal received in the overlapping part of and in the region, and represents the signal received in the The signals received in the region are represented as the channel gains in each terminal where $h_{ij}$ is the transmit power spectral density, $s$ is the transmitted signal, and $n$ is the received noise.

[0017] Furthermore, in step (1), the decoding rate of each UE in different frequency band regions is as follows:

[0018] ;

[0019] where $R_{i1}$ represents the rate of decoding $s_{i1}$ in the $B_{i1}$ region ; $R_{i2}$ represents the rate of decoding its own signal $s_{i2}$ in the overlapping part of the $B_{i1}$ and $B_{i2}$ regions ; $R_{j1}$ represents the rate of decoding $s_{j1}$ in the overlapping part of the $B_{j1}$ and $B_{j2}$ regions ; $R_{j2}$ represents the rate of decoding its own signal $s_{j2}$ in the overlapping part of the $B_{j1}$ and $B_{j2}$ regions ; $R_{i3}$ represents the rate of decoding $s_{i3}$ in the $B_{i3}$ region. The model uses the noise power as normalized; through frequency division hybrid multiple access, the data rate $R$ is obtained, where the minimum unit frequency band rate:

[0020] .

[0021] Furthermore, step (2) is specifically as follows:

[0022] ;

[0023] where $P_{1a}$ represents the transmit power of the base station for $s_{i1}$ ; $P_{1b}$ represents the transmit power of the base station for $s_{i2}$ , , $(P1a)$ is the optimization objective function, that is, the minimum energy consumption of the system, and $(P1b)$ and $(P1c)$ represent that the $s_{i1}$ and $s_{i2}$

[0024] ;

[0025] Among them, , .

[0026] Furthermore, step (3) includes the following steps:

[0027] (31) Set and to the initial value of 0.5;

[0028] (32) Use the method of continuous resource allocation to solve the optimal power allocation solution of (P2);

[0029] (33) Optimize and solve for the occupied by R1, the RE bandwidth shared by the R2 region is , and the bandwidth of the non-overlapping part is ; and ;

[0030] (34) Judge whether the obtained and converge. If they do not converge, go back to step (32). If they converge, the and obtained in step (32) of this iteration and the and obtained in step (33) are the optimal allocation solutions sought.

[0031] Furthermore, step (32) is specifically as follows: First, write the Lagrangian function of (P2) as follows:

[0032] ;

[0033] Among them, is the Lagrange multiplier;

[0034] Then, take the partial derivatives of the Lagrangian function with respect to respectively and set them equal to 0 to obtain and which is the optimal power spectral density allocation solution The formula is as follows:

[0035] ;

[0036] Finally, use the constraint condition (P2d) to verify the obtained and : If in the above formula, then (10) and (11) are the solutions sought. If Then It is expressed as:

[0037] 。

[0038] Furthermore, step (33) is specifically as follows: First, write out the Lagrangian function of (P1) as follows:

[0039] ;

[0040] Wherein, is the Lagrange multiplier;

[0041] Then, take the partial derivative of the Lagrangian function with respect to and set it equal to 0 to obtain and That is, the optimal frequency band allocation coefficient formula is as follows:

[0042] 。

[0043] An electronic device according to the present invention includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the computer program is loaded into the processor, it implements any one of the frequency division hybrid multiple access cellular access network planning methods described above.

[0044] A storage medium according to the present invention stores a computer program, and when the computer program is executed by a processor, it implements any one of the frequency division hybrid multiple access cellular access network planning methods described above.

[0045] Beneficial effects: Compared with the prior art, the present invention has the following remarkable advantages: Using the frequency division non-orthogonal multiple access technology can ensure that each user fully benefits from the advantages of orthogonal multiple access and non-orthogonal multiple access transmissions; By combining multiple access methods, the limited spectrum resources can be utilized to the maximum extent, enabling the network to flexibly adjust resource allocation according to user needs and service types; The optimal power allocation solution obtained by the multi-resource allocation interactive iteration method of the present invention can make the frequency division hybrid multiple access output have low energy consumption and high reliability, etc., and the proposed interactive iteration method has strong universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a flowchart of the planning method of the present invention;

[0047] Figure 2 is a schematic diagram of the frequency division hybrid multiple access scheme of the present invention;

[0048] Figure 3 is a simulation diagram of the total transmit power of the base station vs. the minimum communication rate of the user of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0049] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings.

[0050] As Figure 1 shown, an embodiment of the present invention provides a frequency division hybrid multiple access cellular access network planning method, including the following steps:

[0051] (1) For a wireless communication system including a base station with M configured antennas and two single-antenna configured users, a hybrid multiple access model is constructed; as Figure 2 shown, the hybrid multiple access model is specifically as follows: A downlink cellular network is adopted, and a base station serves two users in each resource element RE through frequency division hybrid multiple access, namely and , and the signals of two users with different powers are mixed and transmitted; the two UEs are sorted according to the channel strength metric: According to the base station at the coordinate system 0, the UEs are sorted according to the connection distance R between it and the UEs uniformly distributed within a disk with as the radius; the strong terminal with a shorter link distance is called , and the weak terminal with a longer link distance is called ; in frequency division hybrid multiple access, the frequency band resource units are divided into three regions, namely , and , and in the region, the proportion of the shared RE is represented by , and is used to represent the proportion of the RE in the area where only can enter , where ; then the proportion of the bandwidth is represented by , the non-overlapping part is represented by ; the base station provides OMA services in the region of user and the region of , and provides NOMA services in the and overlapping region.

[0052] The hybrid multiple access model formula is as follows: In different frequency band regions, namely , and , the terminal receives the following signals:

[0053] ;

[0054] ;

[0055] ;

[0056] ;

[0057] Among them, represents the signal received in the area, represents and the signal received in the overlapping part of the area, represents the signal received in the area, which is expressed as the channel gain of each terminal in , is the transmit power spectral density, s is the transmitted signal, and n is the received noise.

[0058] The decoding rate of each UE in different frequency band regions is as follows:

[0059] ;

[0060] Among them, represents the rate of decoding in the area, represents the rate of decoding itself in the overlapping part of the area, represents the rate of decoding in the overlapping part of the area, represents the rate of decoding itself in the overlapping part of the area, represents the rate of decoding in the area. The model uses the noise power as normalized; through frequency division hybrid multiple access, the

[0061] data rate is obtained, where the minimum unit frequency band rate:

[0061] .

[0062] (2) With the goal of minimizing the system energy consumption, a downlink optimization transmission model with multiple constraints is constructed; specifically as follows:

[0063] ;

[0064] Among them, represents the transmission power of the base station to , represents the transmission power of the base station to , , , (P1a) is the optimization objective function, that is, the minimum energy consumption of the system. In (P1b) and (P1c), the transmission data rates of and need to be greater than or equal to the minimum transmission rate . (P1d) is the power difference requirement set for successful decoding using SIC in the NOMA working mode. The common value range of the constant c is 3 - 10. The objective problem (P1) with minimum energy consumption is rewritten by identity transformation as:

[0065] ;

[0066] Among them, , .

[0067] (3) Use the method of continuous resource allocation interaction iteration to solve the multi-objective energy minimization problem; it includes the following steps:

[0068] (31) Set the initial values of and to be 0.5;

[0069] (32) Use the method of continuous resource allocation to solve the optimal power allocation solution of (P2); specifically as follows: First, write the Lagrangian function of (P2) as follows:

[0070] ;

[0071] Among them, is the Lagrange multiplier;

[0072] Then, take the partial derivatives of the Lagrangian function with respect to and set them equal to 0 to obtain and , that is, the optimal power spectral density allocation solution The formula is as follows:

[0073] ;

[0074] Finally, use the constraint condition (P2d) to verify the obtained and : If in the above formula, then (10) and (11) are the solutions. If , then is expressed as:

[0075] 。

[0076] (33)For the frequency band width occupied by R1 being , and the RE frequency band width shared by the R2 region being , and the frequency band width of the non-overlapping part being of the and perform optimization and solution; specifically as follows: First, write out the Lagrangian function of (P1) as follows:

[0077] ;

[0078] where is the Lagrange multiplier;

[0079] Then, take the partial derivative of the Lagrangian function with respect to and set it equal to 0 to obtain and That is, the optimal frequency band allocation coefficient formula is as follows:

[0080] .

[0081] (34)For the obtained and judge whether it converges. If it does not converge, go to step (32). If it converges, the and obtained in step (32) of this iteration and the and obtained in step (33) are the required optimal allocation solutions.

[0082] (4)Perform access according to the obtained optimal power allocation solution.

[0083] As Figure 3 shows, the simulation diagram of the total transmission power vs. the user decoding rate of the present invention, based on the simulation of the continuous resource allocation interactive iterative optimization strategy, compares the proposed frequency division hybrid multiple access cellular access method with the existing non-orthogonal multiple access technology and orthogonal access technology. It can be seen that while the target data transmission rate is increased, the total energy consumption is also significantly increased, but the energy consumption of orthogonal multiple access is significantly greater than that of frequency division hybrid multiple access, and the non-orthogonal multiple access is slightly higher than that of frequency division hybrid multiple access. Using downlink frequency division hybrid multiple access can achieve significant performance gains. The method we proposed has lower energy consumption and higher stability.

[0084] The embodiment of the present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the computer program is loaded into the processor, it implements any one of the frequency division hybrid multiple access cellular access network planning methods.

[0085] An embodiment of the present invention further provides a storage medium storing a computer program, which, when executed by a processor, implements any one of the frequency division hybrid multiple access cellular access network planning methods described above.

Claims

1. A method for planning a frequency division hybrid multiple access cellular access network, characterized in that: The following steps are involved: (1) For a wireless communication system including a base station with M antennas and two users with single antennas, a hybrid multiple access model is constructed. The hybrid multiple access model is as follows: a downlink cellular network is used, and a base station serves two users in each resource unit RE through frequency division hybrid multiple access. and , the signals of two users with different powers are mixed and transmitted; Sort the two UEs according to the channel strength metric: According to the base station at coordinate 0, it is evenly distributed with The UEs are sorted by the connection distance R between the UEs in the disk with a radius of 1. The strong terminals with shorter link distances are called , the weak terminal with a longer link distance is called ; The frequency band resource unit in frequency division multiple access is divided into three areas, namely , and , and exist The proportion of RE shared by the region is expressed as Indicates that To indicate that only Accessible areas The proportion of RE in ;but The ratio of bandwidth to express, The non-overlapping part Indicates that the base station is in the user of Region and of OMA services are available in the region. and Overlapping NOMA service is provided in different frequency band areas. , and In the process, the terminal receives the following signal: ； ； ； ； in, express exist The signal received in the area express and exist The received signal in the overlapping area, express exist The signal received in the area Represented as each terminal The channel gain, is the transmit power spectral density, s is the transmit signal, and n is the receive noise; (2) With the goal of minimizing system energy consumption, a downlink optimization transmission model under multiple constraints is constructed; the details are as follows: ； in, Indicates base station pair The transmission power, Indicates base station pair The transmission power, , , (P1a) is the optimization objective function, i.e., the minimum energy consumption of the system, (P1b) and (P1c) represent and The transmission data rate must be greater than or equal to the minimum transmission rate , (P1d) is the power difference requirement set for successful decoding using SIC in NOMA mode, and the constant c is commonly in the range of 3-10; the problem (P1) with energy minimization as the goal is rewritten through identity transformation as: ； in, , ; (3) Solve the multi-objective energy minimization problem by using the method of continuous resource allocation interactive iteration; (4) Access is performed based on the obtained optimal power allocation solution.

2. A method for planning a frequency division hybrid multiple access cellular access network according to claim 1, characterized in that: In step (1), the decoding rate of each UE in different frequency band areas is as follows: ； in, Indicated in Decoding in Region The rate of Indicated in Overlapping area The rate at which the decoder itself is Indicated in Overlapping area decoding The rate of Indicated in Overlapping area The rate at which the decoder itself is Indicated in Region decoding The model uses noise power as normalization; through frequency division hybrid multiple access, we get The data rate is Minimum unit bandwidth rate: 。 3. A method for planning a frequency division hybrid multiple access cellular access network according to claim 2, characterized in that ,Step (3) includes the following steps: (31) Settings and The initial value of is 0.5; (32) Using the continuous resource allocation method, find the optimal solution for the power allocation of (P2); (33) For R1, the bandwidth occupied is , the RE bandwidth shared by the R2 region is , the bandwidth of the non-overlapping part is of and Perform optimization solution; (34) What you ask for and Determine whether it converges. If not, go to step (32). If converged, the result of step (32) of this iteration is and and the one obtained in step (33) and This is the optimal allocation solution.

4. A method for planning a frequency division hybrid multiple access cellular access network according to claim 3, characterized in that ,Step (32) is as follows: First, write the Lagrangian function of (P2) as follows: ； in, is the Lagrange multiplier; Then, the Lagrangian function is respectively After taking the partial derivative and setting it equal to 0, we get and That is, the optimal power spectral density allocation solution The formula is as follows: ； Finally, the constraint condition (P2d) is used to obtain and Verification: If the above formula , then (10) and (11) are solved if but Expressed as: 。 5. A method for planning a frequency division hybrid multiple access cellular access network according to claim 4, characterized in that ,Step (33) is as follows: First, write the Lagrangian function of (P1) as follows: ； in, is the Lagrange multiplier; Then, the Lagrangian function is Taking the partial derivative and setting it equal to 0 yields and That is, the formula for the optimal frequency band allocation coefficient is as follows: 。 6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the computer program is loaded into a processor, it implements a frequency division hybrid multiple access cellular access network planning method according to any one of claims 1-5.

7. A storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, a frequency division hybrid multiple access cellular access network planning method according to any one of claims 1-5 is implemented.

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