Frequency division hybrid multiple access cellular access network planning method

Abstract

The invention discloses a frequency division hybrid multiple access cellular access network planning method, which comprises the following steps of: (1) constructing a hybrid multiple access model for a wireless communication system comprising a base station configured with M antennas and two users configured with single antennas; (2) taking system energy consumption minimization as a target, and constructing a downlink optimization transmission model under a multi-constraint condition; (3) solving a multi-target energy minimization problem by adopting a continuous resource allocation interactive iteration method; (4) accessing according to the obtained optimal power distribution solution; according to the method, the advantages of the orthogonal and non-orthogonal multiple access methods are utilized, and the interference can be reduced and the coverage range can be expanded under the condition that the throughput is improved by sharing the resource elements.

Description

Technical Field

[0001] The present invention relates to the technical field of communication engineering, and in particular 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 mobile Internet, the number of mobile devices and data traffic have increased dramatically. 5G networks and their subsequent technologies require more efficient spectrum utilization to cope with the explosive growth in 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 rapidly growing data and large-scale connections has gradually become prominent. Non-orthogonal multiple access technology can improve spectrum efficiency and support large-scale user connections. Non-orthogonal multiple access technology improves throughput, but it introduces additional interference, thereby reducing coverage. Summary of the invention

[0003] Purpose of the invention: The purpose 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 the power spectral density allocation coefficient by constructing a hybrid multiple access model, designing a downlink optimization transmission model under multiple constraints, and solving a multi-objective energy minimization problem, so as to maximize the use of limited spectrum resources and overcome the shortcomings of both 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 comprises the following steps: (1) A hybrid multiple access model is constructed for a wireless communication system consisting of a base station with M antennas and two users with single antennas. (2) With the goal of minimizing system energy consumption, a downlink optimization transmission model under multiple constraints is constructed; (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.

[0005] Furthermore, in step (1), 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, namely 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 available in the region.

[0006] Furthermore, in step (1), the formula of the hybrid multiple access model is as follows: , 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.

[0007] Furthermore, 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 decoded, Indicated in Overlapping area decoding The rate of Indicated in Overlapping area The rate at which the decoder itself is decoded, 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: .

[0008] Furthermore, step (2) is 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, , .

[0009] Furthermore, 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.

[0010] Furthermore, 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: .

[0011] Furthermore, 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: .

[0012] An electronic device described in the present invention includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is loaded into the processor, any one of the frequency division hybrid multiple access cellular access network planning methods described is implemented.

[0013] A storage medium described in 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.

[0014] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the use of 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 transmission; by combining multiple access methods, limited spectrum resources can be used to the maximum extent, so that the network can flexibly adjust resource allocation according to user needs and service types; the optimal power allocation solution obtained by the interactive iterative method of multi-resource allocation of the present invention can make the frequency division hybrid multiple access output have the advantages of low energy consumption and high reliability, and the proposed interactive iterative method has strong universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A flow chart of the method for planning the present invention; Figure 2 A schematic diagram of a frequency division hybrid multiple access scheme of the present invention; Figure 3 This is a simulation diagram of the total transmission power of the base station vs. the minimum communication rate of the user according to the present invention. DETAILED DESCRIPTION

[0016] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0017] like Figure 1 As shown, an embodiment of the present invention provides a method for planning a frequency division hybrid multiple access cellular access network, comprising the following steps: (1) For a wireless communication system consisting of a base station with M antennas and two users with single antennas, a hybrid multiple access model is constructed; Figure 2 As shown in the figure, 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 , mix and transmit the signals of two users with different powers; sort the two UEs according to the channel strength metric: according to the base station at coordinate system 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 available in the region.

[0018] The formula of hybrid multiple access model is as follows: , 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.

[0019] 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 decoded, Indicated in Overlapping area decoding The rate of Indicated in Overlapping area The rate at which the decoder itself is decoded, 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: .

[0020] (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, , .

[0021] (3) Using the method of continuous resource allocation interactive iteration to solve the multi-objective energy minimization problem; including the following steps: (31) Settings and The initial value of is 0.5; (32) The optimal solution of power allocation of (P2) is solved by using the continuous resource allocation method; the details are 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: .

[0022] (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 Optimize and solve; the details are 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: .

[0023] (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.

[0024] (4) Access is performed based on the obtained optimal power allocation solution.

[0025] like Figure 3 As shown in the figure, the simulation diagram of total transmission power vs user decoding rate of the present invention is based on the simulation of continuous resource allocation interactive iterative optimization strategy, and the proposed frequency division hybrid multiple access cellular access method is compared 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 consumed by orthogonal multiple access is significantly greater than that of frequency division hybrid multiple access, and non-orthogonal multiple access is slightly higher than that of frequency division hybrid multiple access. The use of downlink frequency division hybrid multiple access can achieve significant performance gains. The method proposed by us has lower energy consumption and higher stability.

[0026] An embodiment of the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the computer program is loaded into the processor, any one of the frequency division hybrid multiple access cellular access network planning methods is implemented.

[0027] An embodiment of the present invention further provides a storage medium storing a computer program, wherein the computer program, when executed by a processor, implements any one of the frequency division hybrid multiple access cellular access network planning methods.

Claims

1. A method for planning a frequency division hybrid multiple access cellular access network, characterized in that: The following steps are involved: (1) A hybrid multiple access model is constructed for a wireless communication system consisting of a base station with M antennas and two users with single antennas. (2) With the goal of minimizing system energy consumption, a downlink optimization transmission model under multiple constraints is constructed; (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 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, namely 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 available in the region.

3. A method for planning a frequency division hybrid multiple access cellular access network according to claim 2, characterized in that: In step (1), the formula of hybrid multiple access model is as follows: , 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.

4. A method for planning a frequency division hybrid multiple access cellular access network according to claim 3, 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: 。 5. A method for planning a frequency division hybrid multiple access cellular access network according to claim 1, characterized in that: Step (2) is 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, , .

6. A method for planning a frequency division hybrid multiple access cellular access network according to claim 1, 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.

7. A method for planning a frequency-division hybrid multiple access cellular access network according to claim 6, 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: 。 8. A method for planning a frequency-division hybrid multiple access cellular access network according to claim 6, 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: 。 9. 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 1-8.

10. 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 1-8 is implemented.

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