A wireless resource allocation method, apparatus, system, and medium

Abstract

The application provides a wireless resource allocation method, device, system and medium, the method comprising: calculating the first distance between each terminal direct connection user pair and the base station and the second distance between each terminal direct connection user pair and each cellular user respectively; based on the quality of service requirement of each cellular user, calculating the first shortest access distance meeting the minimum signal-to-noise ratio requirement of each cellular user respectively; based on the quality of service requirement of each terminal direct connection user pair, calculating the second shortest access distance meeting the minimum signal-to-noise ratio requirement of each terminal direct connection user pair respectively; for each terminal direct connection user pair, screening the cellular user set whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance; based on the preset throughput optimization target, screening the target cellular user from the cellular user set to perform resource multiplexing with the current terminal direct connection user pair. The interference between the terminal direct connection user pair and the cellular user can be reduced, and the system total throughput and resource multiplexing efficiency can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electronic communication technology, in particular to a wireless resource allocation method, device, system and medium. BACKGROUND

[0002] With the rapid development of the information age, especially the advent of 5G technology, not only can users enjoy low latency and high reliability services, but also provide a native platform for massive access. The rapidly increasing number of cellular users not only generates a huge load on base station (BS) communication, but also makes the limited frequency spectrum resource face serious challenges. Therefore, how to reduce the communication load of the base station and reasonably use the limited communication frequency spectrum resource is particularly important.

[0003] Under this trend of communication development, terminal direct connection (D2D) communication technology has attracted widespread attention due to its unique communication method. It is a short-range wireless communication technology that uses licensed spectrum, allows direct data transmission between devices, and can reuse other cellular (CU) user communication resources. However, the reuse of resource blocks can cause interference between primary CU users and secondary D2D users: including D2D user interference with CU user and CU user interference with D2D user, so interference must be mitigated during resource sharing. The research on interference mitigation technology mainly has two directions, that is, BS uses power control or resource allocation method to mitigate interference. However, previous studies have mostly only considered the communication quality between D2D users or only considered the reliability of CU users, and depend on the BS to know the channel state information (CSI) of all related links, which has large system complexity and overhead.

[0004] Therefore, in actual situations, the complexity and overhead problems of resource allocation in D2D communication need to be considered, so a low-overhead resource allocation method based on distance can be used. However, previous distance-based resource allocation methods mostly only consider the communication quality between D2D users or only consider the reliability of CU users, ignoring the optimization of system total throughput and resource reuse efficiency. SUMMARY

[0005] Therefore, in actual situations, the complexity and overhead problems of resource allocation in D2D communication need to be considered, so a low-overhead resource allocation method based on distance can be used. However, previous distance-based resource allocation methods mostly only consider the communication quality between D2D users or only consider the reliability of CU users, ignoring the optimization of system total throughput and resource reuse efficiency.

[0006] According to a first aspect, the embodiments of the present application provide a wireless resource allocation method applied to a wireless resource allocation system, the wireless resource allocation system comprising a base station, a plurality of cellular users and a plurality of terminal direct connection user pairs, the method comprising:

[0007] respectively calculate a first distance between each terminal direct user pair and the base station and a second distance between each terminal direct user pair and each cellular user;

[0008] respectively calculate a first shortest access distance satisfying a minimum signal-to-interference-and-noise ratio requirement of each cellular user based on a quality of service requirement of each cellular user;

[0009] respectively calculate a second shortest access distance satisfying a minimum signal-to-interference-and-noise ratio requirement of each terminal direct user pair based on a quality of service requirement of each terminal direct user pair;

[0010] for each terminal direct user pair, screen a set of cellular users whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance;

[0011] based on a preset throughput optimization target, screen a target cellular user from the set of cellular users of a current terminal direct user pair for resource reuse with the current terminal direct user pair.

[0012] Optionally, the screening, for each terminal direct user pair, of the set of cellular users whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance, comprises:

[0013] obtaining a current cellular user and determining whether a first distance between a current terminal direct user pair and the base station is greater than a first shortest access distance corresponding to the current cellular user;

[0014] when the first distance between the current terminal direct user pair and the base station is greater than the first shortest access distance corresponding to the current cellular user, determining whether a second distance between the current terminal direct user pair and the current cellular user is greater than a second shortest access distance corresponding to the current terminal direct user pair;

[0015] when the second distance between the current terminal direct user pair and the current cellular user is greater than the second shortest access distance corresponding to the current terminal direct user pair, adding the current cellular user to the set of cellular users of the current terminal direct user pair and continuing to determine a next cellular user until all cellular users are traversed.

[0016] Optionally, the screening, based on a preset throughput optimization target, of a target cellular user from the set of cellular users of a current terminal direct user pair for resource reuse with the current terminal direct user pair, comprises:

[0017] determining an evaluation index parameter based on the preset throughput optimization target;

[0018] respectively obtaining a parameter value of the evaluation index parameter corresponding to each cellular user in the set of cellular users;

[0019] calculating a resource selection function value corresponding to each cellular user based on a parameter value of an evaluation index parameter corresponding to each cellular user in the set of cellular users;

[0020] determining the cellular user with the largest resource selection function value as the target cellular user for resource reuse with the current D2D user pair.

[0021] Optionally, the evaluation index parameter comprises a channel bandwidth, a reuse number and a distance parameter of the cellular user, wherein,

[0022] when the preset throughput optimization target is the system total throughput, the distance parameter is a distance between the cellular user and the current D2D user pair;

[0023] when the preset throughput optimization target is the D2D user pair throughput, the distance parameter is a distance between the cellular user and the current D2D user pair and a first distance between the current D2D user pair and the base station;

[0024] when the preset throughput optimization target is the cellular user throughput, the distance parameter is a distance between the cellular user and the base station.

[0025] Optionally, when there are multiple cellular users with the largest resource selection function value, the method further comprises:

[0026] respectively acquiring a third distance between each cellular user with the largest resource selection function value and the base station;

[0027] determining the target cellular user in the order of the third distance from small to large.

[0028] Optionally, before the target cellular user is selected from the set of cellular users of the current D2D user pair based on the preset throughput optimization target for resource reuse with the current D2D user pair, the method further comprises:

[0029] determining an access order of each D2D user pair in the order of the first distance from large to small;

[0030] selecting the target cellular user from the set of cellular users of the current D2D user pair based on the preset throughput optimization target for resource reuse with the current D2D user pair in the access order.

[0031] Optionally, when the preset throughput optimization target is the system total throughput, the resource selection function value corresponding to the cellular user is calculated by the following formula:

[0032]

[0033] wherein, W ji denotes the resource selection function value corresponding to the i-th cellular user in the cellular user set of the j-th terminal direct user pair, BW ci denotes the channel bandwidth of the i-th cellular user, n denotes the number of terminal direct user pairs which commonly reuse the channel resource of the i-th cellular user, d i，j denotes the distance between the i-th cellular user in the cellular user set of the j-th terminal direct user pair and the j-th terminal direct user pair.

[0034] Optionally, when the cellular user set of the current terminal direct user pair is an empty set, the current terminal direct user pair is rejected to access the wireless resource allocation system.

[0035] According to a second aspect, embodiments of the present application further provide a wireless resource allocation apparatus, applied to a wireless resource allocation system, the wireless resource allocation system comprising a base station, a plurality of cellular users and a plurality of terminal direct user pairs, the apparatus comprising:

[0036] a first calculation module, configured to calculate a first distance between each terminal direct user pair and the base station and a second distance between each terminal direct user pair and each cellular user, respectively;

[0037] a second calculation module, configured to calculate a first shortest access distance satisfying a minimum signal-to-interference-and-noise ratio requirement of each cellular user based on a quality-of-service requirement of each cellular user, respectively;

[0038] a third calculation module, configured to calculate a second shortest access distance satisfying a minimum signal-to-interference-and-noise ratio requirement of each terminal direct user pair based on a quality-of-service requirement of each terminal direct user pair, respectively;

[0039] a first processing module, configured to, for each terminal direct user pair, screen a cellular user set whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance;

[0040] a second processing module, configured to screen a target cellular user from the cellular user set of the current terminal direct user pair to perform resource reuse with the current terminal direct user pair based on a preset throughput optimization target.

[0041] According to a third aspect, embodiments of the present application further provide a wireless resource allocation system, the wireless resource allocation system comprising a base station, a plurality of cellular users and a plurality of terminal direct user pairs, the wireless resource allocation system further comprising a controller, the controller comprising a memory and a processor, the memory and the processor being communicatively connected with each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the wireless resource allocation method according to the first aspect or any optional implementation manner thereof.

[0042] According to a fourth aspect, the embodiments of the present application provide a computer readable storage medium storing computer instructions for causing a computer to perform the wireless resource allocation method of the first aspect, or any of the optional implementation forms thereof.

[0043] The technical scheme of the present application has the following advantages:

[0044] The wireless resource allocation method provided by the embodiments of the present application, by calculating the first distance between each terminal direct user pair and the base station and the second distance between each terminal direct user pair and each cellular user respectively; based on the quality of service requirement of each cellular user, calculating the first shortest access distance meeting the minimum signal-to-interference-and-noise ratio requirement of each cellular user respectively; based on the quality of service requirement of each terminal direct user pair, calculating the second shortest access distance meeting the minimum signal-to-interference-and-noise ratio requirement of each terminal direct user pair respectively; for each terminal direct user pair, screening the cellular user set whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance; based on the preset throughput optimization target, screening the target cellular user from the cellular user set of the current terminal direct user pair for resource reuse with the current terminal direct user pair. Thus, based on the screening of the resource reuse objects of the terminal direct user pair and the cellular user quality of service, the quality of service performance of the cellular user and the terminal direct user pair after resource sharing can be ensured, the reliability of the access user is ensured, and in combination with the resource selection based on the preset throughput optimization target, the interference between the terminal direct user pair and the cellular user can be effectively reduced, and the system total throughput and resource reuse efficiency can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the specific embodiments of the present application or the technical scheme in the prior art, the drawings needed in the specific embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings based on these drawings without creative labor.

[0046] Figure 1 The structure diagram of a wireless resource allocation system according to an embodiment of the present application;

[0047] Figure 2 The flowchart of a wireless resource allocation method according to an embodiment of the present application;

[0048] Figure 3 The specific working process diagram of the wireless resource allocation according to an embodiment of the present application;

[0049] Figure 4 The step diagram of the D2D user pair pre-grouping method according to an embodiment of the present application;

[0050] Figure 5A Performance analysis diagram of system total throughput under three optimization objectives of the embodiment of the present application;

[0051] Figure 5B Performance analysis diagram of CU user SINR-CDF of the embodiment of the present application;

[0052] Figure 5C Comparison diagram of system total throughput under two algorithms of the embodiment of the present application;

[0053] Figure 5D Performance analysis diagram of system average multiplexing efficiency under two algorithms of the embodiment of the present application;

[0054] Figure 6 Structure diagram of a wireless resource allocation device of the embodiment of the present application;

[0055] Figure 7 Structure diagram of a controller in a wireless resource allocation system of the embodiment of the present application. DETAILED DESCRIPTION

[0056] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0057] The technical features involved in different embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0058] The embodiment of the present application proposes a low-overhead resource allocation scheme based on distance, and the specific implementation process mainly consists of two parts. The first part is D2D user access control and pre-grouping based on the positions of D2D users. This part is to determine which D2D user pairs can be allowed to access the network under the condition of meeting their own and CU user quality of service (hereinafter referred to as QoS). And the accessible D2D user pairs are grouped to determine which CU users they can share resources with. The second part is to define a resource selection function, which can be set according to needs. The default is to optimize the system total throughput, or to optimize the D2D user throughput or the CU user throughput, or to set a custom selection function according to actual communication needs. Through the selection function, the accessible D2D user pairs are calculated to make the final resource selection in the potential CU user set.

[0059] This invention proposes a distance-based low-overhead resource allocation scheme. Considering the scenario where multiple direct-connect user pairs (D2D user pairs) reuse the resources of multiple cellular users (CU users), a resource allocation scheme is proposed based on the communication distance between D2D users, CU users, and the base station, while simultaneously ensuring the QoS (Quality of Service) requirements of both CU users and D2D user pairs. This scheme combines pre-grouping and resource selection with a resource reuse function matrix, comprehensively reducing C2D and D2C interference and improving the overall system throughput. Numerical simulation results show that compared with the greedy heuristic algorithm, this scheme can improve the overall system throughput by approximately 4% and the average system reuse efficiency by more than 2 times.

[0060] Specifically, embodiments of the present invention provide a wireless resource allocation method, applied to, for example... Figure 1 The wireless resource allocation system shown includes: a base station (BS), four cellular users (CU1, CU2, CU3, CU4), and three direct-connect user pairs (Pair1, Pair2, Pair3). The system also includes a controller. Figure 1 (Not shown in the diagram). For a detailed description of the controller's operation in the method embodiments below, please refer to the relevant description; it will not be repeated here. It should be noted that... Figure 1 This explanation uses a system with 4 CU users and 3 D2D user pairs as an example. In practical applications, the number of CU users and D2D user pairs can be flexibly set, and this invention is not limited thereto. Furthermore, in this embodiment of the invention, to ensure the quality of resource reuse, the maximum number of resources reused by each CU user is limited to k=2. That is, each CU user's resource block can ultimately only be reused by 2 D2D user pairs. In practical applications, the value of k can be flexibly chosen according to the actual situation, and this invention is not limited thereto.

[0061] Figure 2 A flowchart of a wireless resource allocation method according to an embodiment of the present invention is shown, such as... Figure 2 As shown, the wireless resource allocation method specifically includes the following steps:

[0062] Step S101: Calculate the first distance between each terminal's direct-connected user pair and the base station, and the second distance between each terminal and each cellular user.

[0063] The first distance and the second distance can be calculated based on the distribution of direct-connected user pairs, cellular users and base stations, according to the distance between the two points.

[0064] Step S102: based on the quality of service requirement of each cellular user, respectively calculate the first shortest access distance satisfying the minimum signal to interference and noise ratio requirement of each cellular user.

[0065] Wherein, the quality of service requirement of different cellular users may also be different, and the minimum signal to interference and noise ratio (hereinafter referred to as SINR) requirement is also different, and the calculation process of calculating the first shortest access distance satisfying the minimum signal to interference and noise ratio requirement of each cellular user according to the quality of service requirement of the cellular user is the prior art, which can be referred to the relevant description of the prior art, and will not be repeated here.

[0066] Step S103: based on the quality of service requirement of each terminal direct connection user pair, respectively calculate the second shortest access distance satisfying the minimum signal to interference and noise ratio requirement of each terminal direct connection user pair.

[0067] Wherein, similar to the cellular user, the quality of service requirement of different terminal direct connection user pairs may also be different, and the minimum signal to interference and noise ratio (hereinafter referred to as SINR) requirement is also different, and the calculation process of calculating the second shortest access distance satisfying the minimum signal to interference and noise ratio requirement of each terminal direct connection user pair according to the quality of service requirement of the terminal direct connection user pair is the prior art, which can be referred to the relevant description of the prior art, and will not be repeated here.

[0068] Step S104: for each terminal direct connection user pair, screen the cellular user set whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance.

[0069] Specifically, in an embodiment, when the cellular user set of the current terminal direct connection user pair is empty, the current terminal direct connection user is rejected to access the wireless resource allocation system. If the cellular user set is empty, it means that the current terminal direct connection user pair cannot match the CU user for resource reuse, that is, it cannot be allocated with resources, therefore, the system will reject its access request to prompt the D2D user pair.

[0070] Step S105: based on the preset throughput optimization target, screen the target cellular user from the cellular user set of the current terminal direct connection user pair for resource reuse with the current terminal direct connection user pair.

[0071] Wherein, each cellular user in the cellular user set is a cellular user that can perform resource reuse for the current terminal direct connection user pair, and by screening the CU user for resource reuse from the set, the system throughput optimization target can be achieved, and the resource reuse efficiency can be improved.

[0072] Specifically, in an embodiment, the above step S104 specifically includes the following steps:

[0073] Step S41: Acquire the current cellular user, and determine whether the first distance between the current terminal direct connection user pair and the base station is greater than the first shortest access distance corresponding to the current cellular user.

[0074] Step S42: When the first distance between the current terminal direct connection user pair and the base station is greater than the first shortest access distance corresponding to the current cellular user, determine whether the second distance between the current terminal direct connection user pair and the current cellular user is greater than the second shortest access distance corresponding to the current terminal direct connection user pair.

[0075] Step S43: When the second distance between the current terminal direct connection user pair and the current cellular user is greater than the second shortest access distance corresponding to the current terminal direct connection user pair, add the current cellular user to the cellular user set of the current terminal direct connection user pair, and continue to determine the next cellular user until all cellular users are traversed.

[0076] Specifically, in an example, as shown in Figure 3 The first part of the above resource allocation process needs to perform access control on the D2D user pair requesting access and perform pre-grouping, and the pre-grouping process is as shown in Figure 4 The specific steps are as follows:

[0077] 1) Obtain the resource reuse indication function matrix P according to the system model as shown in Figure 1

[0078]

[0079] 2) Rearrange the column vectors in the matrix P according to the distance between the CU user and the BS from near to far, i.e., according to d i，B (CU user distance from BS) from small to large. Assuming that the distance between each CU user and the BS in the system is d 2，B <d 1，B <d 4，B <d 3，B , the above matrix P becomes:

[0080]

[0081] 3) According to the QoS of the CU user, calculate the shortest access distance d i，min that satisfies the minimum SINR (signal-to-interference noise ratio) requirement for each CU user. Only when the distance d j between the D2D user pair D j，B and the BS is greater than the shortest access distance of the CU user CU i , D j can reuse the resource of CU i . Specifically, for each CU user CU i ​(i∈{1,2,3,4}) and D2D user pair D j (j∈{1,2,3}) calculate the shortest access distance and After the calculation, distance judgment is made.

[0082] 4) According to the QoS of the D2D user, calculate the shortest access distance d j，min for each D2D user pair D j only when the distance d i between D i，j and CU j is greater than the shortest access distance of D j , D i will choose the channel resource of CU j for reuse.

[0083] 5) For each D2D user pair D j，min trying to access the network, according to the calculated shortest access distance d i , judge whether each CU user in the system can be selected for reuse. If it is satisfied, compare the distance d j between D j，B and the BS with the shortest access distance d i of the user CU i，min , further judge whether D j can reuse the resource of CU i . If it is satisfied, put CU i into the potential reuse user set R j of D j , otherwise set the resource reuse indication function in the matrix P to 0. Observe the potential reuse user set R j of each D2D user pair D j , if R j is an empty set, it means that D j cannot access the system network, and the dimension of the matrix P is reduced.

[0084] Exemplarily, first for CU2, compare the distances between D2D user pairs D1, D2, D3 and the BS with the shortest access distance of CU2 in turn. The comparison results are and Since D3 does not meet the access condition of CU2, set to 0. Since the CU users behind CU2 are not allowed to access, set and to 0. D1 and D2 can meet the access condition of CU2, further judge the distance d2，1 Shortest access distance to D1 Comparison is made, and the following is obtained The multiplexing condition is satisfied, and CU2 is put into the potential multiplexing set R1 of D1. Then the distance d 2，2 Shortest access distance to D2 Comparison is made, and the following is obtained The multiplexing condition is satisfied, and CU2 is put into the potential multiplexing set R2 of D2.

[0085] Then, for the user CU1, the distance judgment is also made. Since Has been set to zero, only the judgment of D1 and D2 is needed. The following is obtained D1 and D2 can satisfy the access condition of CU1, and further judgment is made. The distance d 1，1 The distance d 1，2 Between D2 and CU1 is compared with the shortest access distance of D1 and D2 respectively, and the following is obtained Therefore, it is known that CU1 can satisfy the multiplexing condition of D2, while CU1 cannot satisfy the multiplexing condition of D1, and Is set to 0.

[0086] Similarly, the distance judgment is made for CU4 and CU3, and the potential multiplexing sets of the three D2D user pairs are R1={CU2, CU4}, R2={CU1, CU2, CU4}, And the resource multiplexing indication function matrix P is valued.

[0087] The matrix P after pre-grouping is as follows:

[0088]

[0089] From the potential multiplexing set of the D2D user pair, it is known that the D2D user pair D3 is not allowed to access the network. In summary, after the access control and pre-grouping in the first step, the allocation result of the D2D user pair is shown in the following Table 1:

[0090] Table 1 Allocation result of D2D user pair after pre-grouping

[0091] D2D user pair Whether to allow access Potential multiplexing set [CD AT D1] Yes CU2, CU4 [D2] Yes CU1, CU2, CU4 [D3] No /

[0092] In addition, the matrix P can be further simplified to the matrix P' as follows:

[0093]

[0094] Specifically, in an embodiment, the above step S105 specifically includes the following steps:

[0095] Step S51: determining the evaluation index parameter based on a preset throughput optimization target.

[0096] Specifically, the evaluation index parameter comprises a channel bandwidth of the cellular user, a multiplexing number and a distance parameter. When the preset throughput optimization target is the system total throughput, the distance parameter is a distance between the cellular user and the current D2D user pair. When the preset throughput optimization target is the D2D user pair throughput, the distance parameter is a distance between the cellular user and the current D2D user pair and a first distance between the current D2D user pair and the base station. When the preset throughput optimization target is the cellular user throughput, the distance parameter is a distance between the cellular user and the base station.

[0097] Step S52: Obtain the parameter value of the evaluation index parameter corresponding to each cellular user in the cellular user set respectively.

[0098] Step S53: Calculate the resource selection function value corresponding to each cellular user based on the parameter value of the evaluation index parameter corresponding to each cellular user in the cellular user set respectively.

[0099] Specifically, in an embodiment, when the preset throughput optimization target is the system total throughput, the resource selection function value corresponding to the cellular user is calculated by the following formula:

[0100]

[0101] wherein, W j i denotes the resource selection function value corresponding to the i th cellular user in the cellular user set of the j th D2D user pair, BW ci denotes the channel bandwidth of the i th cellular user, n denotes the number of D2D user pairs which commonly multiplex the channel resource of the i th cellular user, d i，j denotes the distance between the i th cellular user in the cellular user set of the j th D2D user pair and the j th D2D user pair.

[0102] Step S54: Determine the cellular user with the maximum resource selection function value as the target cellular user to perform resource multiplexing with the current D2D user pair.

[0103] Specifically, in an embodiment, before performing the above step S105, the wireless resource allocation method provided by the embodiment of the present application further comprises the following steps:

[0104] Step S106: Determine the access order of each D2D user pair in the order of the first distance from large to small. Then, perform the above step S105 on each current D2D user pair in the access order. In actual application, the farther the D2D user pair is from the base station, the higher the priority of the D2D user pair to access the system and perform resource multiplexing with the cellular user, so as to guarantee the communication quality of the D2D user pair far from the base station and improve the user experience.

[0105] Specifically, in an embodiment, when there are multiple cellular users with the maximum resource selection function value, the above method further comprises the following steps:

[0106] Step S55: A third distance between each cellular user with the maximum resource selection function value and the base station is obtained respectively.

[0107] Step S56: A target cellular user is determined in the order of the third distance from small to large.

[0108] Specifically, since the closer to the base station the CU user is, the better the quality of the resource signal of the CU user is, the CU user closest to the base station is preferentially selected for resource reuse, so as to further improve the resource reuse efficiency and guarantee the service quality of the CU user and the D2D user.

[0109] Specifically, in an example, in the first part of the above resource allocation process, a set of potential CU users R j has been found for each accessible D2D user pair D j by the distance-based pre-grouping method. j Resource selection is performed in the set of potential CU users R

[0110] Exemplarily, the resource selection considers the following aspects, first, a channel bandwidth is preferentially selected. Second, a distance variable d i，j (CU user to D2D user pair distance), which affects C2D interference. In addition, since interference also occurs between D2D user pairs that select the same resource block, a variable n is introduced in the resource selection function to represent the number of times the resource block is reused, and n is incremented each time the resource block of the user CU i is reused. They are represented in the form of a ratio in the resource selection function. The larger the ratio is, the smaller the interference to the D2D user pair is.

[0111] The resource allocation scheme provided by the embodiment of the application can select the calculation of the resource selection function as needed, and exemplarily, the optimization target of the resource selection can be optimizing the total system throughput, optimizing the D2D user throughput, and optimizing the CU user throughput, etc., and in actual application, a selection function can also be customized. Wherein, the embodiment of the application is described by taking the calculation formula of the resource selection function as an example of optimizing the total system throughput, and the optimal CU user resource is found in the potential set R j for each accessible D2D user pair D j to select.

[0112] Exemplarily, the resource selection function formula can be calculated according to the following three formulas as needed:

[0113] Default selection: (Optimize total system throughput);

[0114] Option 1: (Optimize D2D user throughput)

[0115] Option 2: W j i =BW ci *d i，B (Optimize CU user throughput)

[0116] Among them, W j i BW represents the resource selection function value corresponding to the i-th cellular user in the cellular user set of the j-th terminal direct-connected user pair. ci Let d represent the channel bandwidth of the i-th cellular user, n represent the number of terminal direct-connect user pairs that share the channel resources of the i-th cellular user, and d represent the channel bandwidth of the i-th cellular user. i，j d represents the distance between the i-th cellular user and the j-th direct-connected user pair in the cellular user set of the j-th terminal direct-connected user pair. j，B d represents the distance between the j-th terminal directly connected user pair and the base station. i，B This represents the distance between the i-th cellular user and the base station. The specific resource selection steps are as follows:

[0117] (1) is a set R j Each CU user in the process performs a resource selection function value W. j i Calculation;

[0118] (2) In set R j The CU user with the largest function value is selected for reuse. The selection result is then mapped to matrix P′. For example, if D... j With CU i Resource selection function value W j i If the maximum value is found, then the corresponding matrix P' will be... Set to 1.

[0119] Finally, the final matrix P′ was determined based on the results of the resource selection function, resulting in the final resource allocation scheme.

[0120] For example, the second part of the above resource allocation process is based on the default resource selection function W. j i Perform resource selection. Before selecting resources, first categorize the accessible D2D pairs according to their distance d from the BS. j，BReordering from large to small, which will determine the access order of D2D pairs. Assume that the distances between the accessible D2D pairs D1, D2 and the BS are d 1，B > d 2，B , which is exactly the same as the previous order, so the D2D pairs do not need to be rearranged, and the matrix P' also does not need to be transformed.

[0121] First, D2D pair D1, respectively, calculate the resource selection function of D1 and CU2, CU4 and Assume that the bandwidth of each channel resource is consistent, all w. And the resources of CU2 and CU4 are not reused at this time, so the reuse times n of the two are both 1. At this time, the resource selection functions of the two are: At this time, mainly compare the size of d 1，1 and d 2，1 , select the CU user corresponding to the distance to be reused. In the system model of this example, d 1，1 = d 2，1 , so that the resource selection functions of the two are equal. At this time, further consider the distance of CU2 and CU4 from the BS, and prefer to select the CU user closer to the BS for reuse. Since d 2，B < d 1，B in this example, D1 selects CU2 for reuse, and sets in matrix P' to 1.

[0122] Next, D2D pair D2, respectively, calculate the resource selection function of D2 and CU t , CU2, CU4 Since CU2 has been reused, the reuse times n of CU2 = 2, compared with the system limit reuse times k = 2, since n ≤ k, therefore CU2 can still be reused. At this time, the resource selection functions of the three are: and In the system model of this example, d 4，2 < d 1，2 < d 2，2 , but since D2 selects CU1 for reuse, and sets in matrix P' to 1. According to the characteristics of matrix , other resource reuse indicator functions can be set to zero.

[0123] The final matrix P' is as follows:

[0124]

[0125] ​From the matrix P', it can be seen that after the resource selection, the multiplexing result of the D2D user pairs is shown in Table 2:

[0126] Table 1 Final result of resource allocation

[0127] D2D user pair Whether to allow access Final resource selection [D1] Yes CU2 [D2] Yes CU1 [D3] No /

[0128] In the prior art, the resource allocation scheme based on distance is mainly to utilize the distance between the cellular user and the receiving end of the D2D user, and form a two-dimensional distance matrix. The pre-grouping of the cellular user resource multiplexing is completed by judging the distance in the matrix, and each cellular user resource can be multiplexed by at most 3 D2D user pairs. The main optimization goal is to ensure the communication quality requirement between users of all D2D user pairs. The resources of the whole system are allocated for multiplexing multiple cellular user resources by multiple D2D user pairs. However, in this scheme, the priority of the communication quality requirement of the cellular user is not taken into account.

[0129] According to the resource allocation scheme in the prior art, first, a two-dimensional distance matrix Q is formed according to the system model as shown in Figure 1 The matrix Q is as follows:

[0130]

[0131] Next, the D2D user pairs are sequentially found to be farthest from the CU user. The first one is the D2D user D1. Assuming that the distance between D1 and each CU user in the model is in the order of d 1，1 <d 2，1 <d 4，1 <d 3，1 , D1 selects the resource of CU3 for multiplexing. The second one is the D2D user D2. Assuming that the distance between D2 and each CU user is in the order of d 4，2 <d 3，2 <d 1，2 <d 2，2 , D2 selects the resource of CU2 for multiplexing. The third one is the D2D user D3. Assuming that the distance between D3 and each CU user is in the order of d 2，3 <d 4，3 <d 1，3 <d 3，3 , CU3 is farthest from D3, and since the multiplexing number of CU3 does not exceed the set maximum multiplexing number k, D3 also selects the resource of CU3 for multiplexing. After the resource selection of this scheme, the multiplexing result of the D2D user pairs is shown in Table 3:

[0132] Table 2 Final result of resource allocation of the prior art scheme

[0133] D2D user pair Whether to allow access Final resource selection [D1] Yes CU3 [D2] Yes CU2 [D3] Yes CU3

[0134] Although the access rate of D2D user pairs is higher in the prior art scheme, it does not consider the QoS of CU users after being resource multiplexed. Meanwhile, it does not consider the interference between D2D user pairs when multiplexing the same resource block.

[0135] The resource allocation scheme provided by the embodiment of the application supports multiplexing multiple D2D user pairs with the resources of multiple CU users, and can guarantee the QoS performance of CU users and D2D users after resource sharing, and guarantee the reliability of access users. The pre-grouping and resource selection are combined with the resource multiplexing function matrix, the interference of D2D user pairs to CU users and the interference of CU users to D2D users are comprehensively reduced, and the system total throughput and resource multiplexing efficiency are improved.

[0136] The beneficial effects achieved by the application will be described below from two aspects. First, the reliability of the application is described, that is, it is verified that the application can achieve the target to be achieved. Second, the effectiveness of the application is described by comparing the improved resource allocation scheme of the prior art, and it is verified that the application has significant improvement in the system total throughput and resource multiplexing efficiency.

[0137] In the experiment, M CU users and N pairs of D2D users are randomly deployed in a cell with the BS as the origin and the radius R, and they all share the uplink bandwidth W of the network. Since the communication distance of D2D user pairs is usually short and dynamically changes, in this paper, the transmitting end and the receiving end of a pair of D2D users are uniformly distributed in a cluster with a radius r, and the cluster center is randomly distributed in the cell. N pairs of D2D users are in N independent clusters. The specific simulation parameters are given in Table 4.

[0138] Table 3 Experimental parameter table

[0139] Parameter Value Cell radius R (m) 500 D2D cluster radius r (m) 100 Cellular user transmit power (dBm) 21 D2D transmitter transmit power (dBm) 21 Number of CU users M 20 Number of D2D user pairs N 2，4，6…18 Number of resource blocks K 20 Path loss constant λ 10 -2 ]] Path loss exponent α 4 Multipath fading Exponential distribution with mean 1 Shadow fading Lognormal distribution with standard deviation 8 dB Channel bandwidth (MHz) 1 Noise power (dBm) -114 User SINR threshold (dB) 2，5 Resource block multiplexing limit k 1，2，3 Simulation times 100000

[0140] First, the reliability of the application is verified by the following two indexes: the system total throughput and the cumulative distribution function (CDF) of the SINR of CU users. They are respectively the sum of the throughputs of CU users and accessed D2D user pairs in the system and the cumulative distribution function of the SINR of CU users after resource sharing.

[0141] The optimization target of the present application is to simultaneously satisfy the QoS conditions of CU users and D2D users, and to comprehensively improve the throughput of CU users and D2D users, thereby maximizing the system throughput. The prior art mainly considers the following two optimization targets: ① maximizing the throughput of D2D users while satisfying the QoS conditions of CU users; and ② maximizing the throughput of CU users while satisfying the QoS conditions of D2D users. In fact, the total system throughput under the optimization target of the present application should include the maximum value of the total system throughput under the above two targets. Therefore, the present application compares and analyzes the total system throughput under the three optimization targets, as shown in FIG. 8. Figure 5A As shown in FIG. 8, the results show that the total system throughput under the optimization target of the present application is higher than that under the other two targets.

[0142] Figure 5B The cumulative distribution function of SINR of CU users after resource sharing is compared between the method proposed in the present application (denoted as Proposed scheme in the figure) and the prior art scheme (hereinafter referred to as Heuristic algorithm, denoted as Greedy heuristic in the figure). As shown in FIG. 9, assuming that the SINR threshold of CU users in the system is 5 dB, about 30% of the CU users in the Heuristic algorithm cannot satisfy the QoS requirements, while all the CU users in the algorithm proposed in the embodiment of the present application can satisfy the requirements, achieving the optimization target. Figure 5B

[0143] Secondly, the following two indicators are used to verify the effectiveness of the proposed application: the total system throughput and the average multiplexing efficiency of the system. The former has been discussed, and the latter refers to the ratio of the total throughput of D2D users to the reduced throughput of CU users before and after resource sharing. For example, when the total throughput of D2D users is the same, the less the throughput sacrificed by CU users, the higher the resource multiplexing efficiency.

[0144] Figure 5C ​The system total throughput of the algorithm (denoted as Proposed scheme in the figure) provided by the embodiment of the present application and the Heuristic algorithm (denoted as Greedy heuristic in the figure) is compared, and the influence of the resource reuse number k on the system throughput is analyzed. In the algorithm, when k increases, the system throughput also increases. This is because when the resource block reuse number increases, the accessed D2D user pairs also increase. In the Heuristic algorithm, when the D2D user pairs increase, the system total throughput when the resource block reuse number k of the CU user is 2 or 3 is smaller than when k is 1, because the Heuristic algorithm does not consider the interference between the D2D user pairs when sharing the same resource. When the D2D user pairs increase, the interference between them also increases, which leads to a significant decrease in the throughput of the D2D user pairs. When the reuse number is the same, the system total throughput of the algorithm is about 4% higher than that of the Heuristic algorithm on average.

[0145] From Figure 5D It can be seen that the system reuse efficiency of the technical solution (denoted as Proposed scheme in the figure) provided by the embodiment of the present application is much higher than that of the Heuristic algorithm (denoted as Greedy heuristic in the figure). This is because the technical solution provided by the present application improves the throughput of the D2D user pairs while controlling the sacrifice of the throughput of the CU user. Under the same conditions, the reuse efficiency of the technical solution provided by the embodiment of the present application can be increased by more than 2 times.

[0146] By performing the above steps, the wireless resource allocation method provided by the embodiment of the present application can ensure the service quality performance of the cellular user and the terminal direct connection user pair after resource sharing, ensure the reliability of the accessed user, effectively reduce the interference between the terminal direct connection user pair and the cellular user, and improve the system total throughput and the resource reuse efficiency by screening the resource reuse objects based on the service quality of the cellular user and the terminal direct connection user pair.

[0147] Figure 6 The structure schematic diagram of the wireless resource allocation device provided by the present application is shown, as Figure 6 shown, the wireless resource allocation device specifically includes:

[0148] The first calculation module 101 is configured to calculate the first distance between each terminal direct connection user pair and the base station and the second distance between each terminal direct connection user pair and each cellular user, respectively. For details, refer to the related description of step S101 in the method embodiment.

[0149] The second calculation module 102 is configured to calculate a first shortest access distance meeting a minimum signal-to-interference-and-noise ratio requirement of each cellular user based on a quality-of-service requirement of each cellular user.

[0150] The third calculation module 103 is configured to calculate a second shortest access distance meeting a minimum signal-to-interference-and-noise ratio requirement of each terminal direct connection user pair based on a quality-of-service requirement of each terminal direct connection user pair. For details, refer to the related description of step S103 in the method embodiment.

[0151] The first processing module 104 is configured to, for each terminal direct connection user pair, screen a set of cellular users whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance. For details, refer to the related description of step S104 in the method embodiment.

[0152] The second processing module 105 is configured to, based on a preset throughput optimization target, screen a target cellular user from the set of cellular users of the current terminal direct connection user pair for resource multiplexing with the current terminal direct connection user pair. For details, refer to the related description of step S105 in the method embodiment.

[0153] The wireless resource allocation apparatus provided by the embodiment of the present application is used to execute the wireless resource allocation method provided by the above-mentioned embodiment, and the implementation manner and principle are the same, and for details, refer to the related description of the method embodiment, which will not be repeated here.

[0154] Through the cooperation of the above-mentioned components, the wireless resource allocation apparatus provided by the embodiment of the present application can guarantee the quality-of-service performance of the cellular user and the terminal direct connection user pair after resource sharing, guarantee the reliability of the access user, effectively reduce the interference between the terminal direct connection user pair and the cellular user, and improve the system total throughput and resource multiplexing efficiency through the screening of the resource multiplexing objects based on the quality-of-service of the terminal direct connection user pair and the cellular user.

[0155] Figure 7 The structure diagram of the controller in the wireless resource allocation system of the embodiment of the present application is shown in FIG. 9. Figure 7 As shown in FIG. 9, the controller can include a processor 901 and a memory 902, wherein the processor 901 and the memory 902 can be connected through a bus or other means, Figure 7 For example, the connection through the bus.

[0156] The processor 901 can be a central processing unit (CPU). The processor 901 can also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, or combinations thereof.

[0157] The memory 902, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs and modules, such as program instructions / modules corresponding to the methods in the above method embodiments. The processor 901 performs various functional applications and data processing of the processor by running the non-transitory software programs, instructions and modules stored in the memory 902, that is, implements the methods in the above method embodiments.

[0158] The memory 902 can include a program storage area and a data storage area, where the program storage area can store an operating system, at least one application required by a function; and the data storage area can store data created by the processor 901 and the like. In addition, the memory 902 can include a high-speed random access memory, and can also include a non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state memory device. In some embodiments, the memory 902 can optionally include a memory disposed remotely with respect to the processor 901, and these remote memories can be connected to the processor 901 through a network. Examples of the above network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0159] One or more modules are stored in the memory 902, and when executed by the processor 901, the methods in the above method embodiments are performed.

[0160] The above controller specific details can be understood by referring to the corresponding related descriptions and effects in the above method embodiments, which will not be repeated here.

[0161] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The program can be stored in a computer readable storage medium. When the program is executed, the program can include the processes of the above-mentioned embodiment methods. The storage medium can be a magnetic disc, an optical disc, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), etc. The storage medium can also include a combination of the above-mentioned types of memories.

[0162] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A wireless resource allocation method, applied to a wireless resource allocation system, the wireless resource allocation system comprising: A base station, a number of cellular users, and a number of terminal-directly-connected user pairs, characterized in that the method includes: Calculate the first distance between each terminal's directly connected user pair and the base station, and the second distance between each terminal and each cellular user; Based on the service quality requirements of each cellular user, calculate the first shortest access distance that meets the minimum signal-to-interference-plus-noise ratio requirement of each cellular user; Based on the service quality requirements of each terminal direct-connected user pair, calculate the second shortest access distance that meets the minimum signal-to-interference-plus-noise ratio requirement of each terminal direct-connected user pair. For each terminal-connected user pair, filter the set of cellular users where the first distance is greater than the first shortest access distance and the second distance is greater than the second shortest access distance; Based on a preset throughput optimization target, target cellular users are selected from the set of cellular users of the current terminal directly connected user pairs for resource reuse. The step of selecting target cellular users from the set of cellular users directly connected to the current terminal for resource reuse based on a preset throughput optimization target includes: The evaluation index parameters are determined based on the preset throughput optimization target; Obtain the parameter values ​​of the evaluation index parameters corresponding to each cellular user in the cellular user set; Based on the parameter values ​​of the evaluation index parameters corresponding to each cellular user in the cellular user set, calculate the resource selection function value corresponding to each cellular user; The cellular user with the largest resource selection function value is identified as the target cellular user and the current terminal directly connected user is used for resource reuse. The evaluation metrics include: cellular user channel bandwidth, multiplexing frequency, and distance parameters, among which... When the preset throughput optimization target is the total system throughput, the distance parameter is the distance between the cellular user and the current terminal directly connected user pair; When the preset throughput optimization target is the throughput of the terminal direct connection user pair, the distance parameter is the distance between the cellular user and the current terminal direct connection user pair and the first distance between the current terminal direct connection user pair and the base station; When the preset throughput optimization target is cellular user throughput, the distance parameter is the distance between the cellular user and the base station.

2. The method according to claim 1, characterized in that, The step of filtering a set of cellular users for each terminal-directly connected user pair where the first distance is greater than the first shortest access distance and the second distance is greater than the second shortest access distance includes: Obtain the current cellular user and determine whether the first distance between the current terminal directly connected user and the base station is greater than the first shortest access distance corresponding to the current cellular user; When the first distance between the current terminal directly connected user pair and the base station is greater than the first shortest access distance corresponding to the current cellular user, it is determined whether the second distance between the current terminal directly connected user pair and the current cellular user is greater than the second shortest access distance corresponding to the current terminal directly connected user pair. When the second distance between the current terminal directly connected user pair and the current cellular user is greater than the second shortest access distance corresponding to the current terminal directly connected user pair, the current cellular user is added to the cellular user set of the current terminal directly connected user pair, and the next cellular user is determined, until all cellular users have been traversed.

3. The method according to claim 1, characterized in that, When there are multiple cellular users with the largest resource selection function value, the method further includes: Obtain the third distance between the cellular user and the base station that has the largest resource selection function value for each user. Target cellular users are determined according to the third distance from smallest to largest.

4. The method according to claim 1, characterized in that, Before selecting target cellular users and current terminal directly connected user pairs from the set of cellular users of the current terminal directly connected user pairs for resource reuse based on a preset throughput optimization target, the method further includes: The access order of each terminal's direct-connection user pair is determined according to the order of the first distance from largest to smallest; According to the access order, based on the preset throughput optimization target, target cellular users are selected from the set of cellular users of the current terminal directly connected user pairs for resource reuse.

5. The method according to claim 1, characterized in that, When the set of cellular users for the current terminal directly connected user pair is empty, the current terminal directly connected user is denied access to the radio resource allocation system.

6. A wireless resource allocation device, applied to a wireless resource allocation system, the wireless resource allocation system comprising: A base station, a plurality of cellular users, and a plurality of terminal-directly-connected user pairs, characterized in that the apparatus comprises: The first calculation module is used to calculate the first distance between each terminal directly connected user and the base station and the second distance between each terminal and each cellular user. The second calculation module is used to calculate the first shortest access distance that meets the minimum signal-to-interference-plus-noise ratio requirement for each cellular user based on the service quality requirements of each cellular user. The third calculation module is used to calculate the second shortest access distance that meets the minimum signal-to-interference-plus-noise ratio requirement for each terminal direct-connected user pair based on the service quality requirements of each terminal direct-connected user pair. The first processing module is used to filter, for each terminal-connected user pair, a set of cellular users whose first distance is greater than the first shortest access distance and whose second distance is greater than the second shortest access distance; The second processing module is used to select target cellular users from the set of cellular users of the current terminal directly connected user pairs for resource reuse based on a preset throughput optimization target. The process of selecting target cellular users from the set of cellular users of the current terminal directly connected user pairs for resource reuse based on the preset throughput optimization target includes: determining evaluation index parameters based on the preset throughput optimization target; obtaining the parameter values ​​of the evaluation index parameters corresponding to each cellular user in the set of cellular users; calculating the resource selection function value corresponding to each cellular user based on the parameter values ​​of the evaluation index parameters corresponding to each cellular user in the set of cellular users; and applying the resource selection function value to the target cellular user pair. The cellular user with the largest function value is determined as the target cellular user and the current terminal directly connected user pair for resource reuse. The evaluation index parameters include: the channel bandwidth, reuse count, and distance parameter of the cellular user. When the preset throughput optimization target is the total system throughput, the distance parameter is the distance between the cellular user and the current terminal directly connected user pair; when the preset throughput optimization target is the throughput of the terminal directly connected user pair, the distance parameter is the distance between the cellular user and the current terminal directly connected user pair and the first distance between the current terminal directly connected user pair and the base station; when the preset throughput optimization target is the throughput of the cellular user, the distance parameter is the distance between the cellular user and the base station.

7. A wireless resource allocation system, the wireless resource allocation system comprising: A base station, several cellular users, and several terminal-directly-connected user pairs, characterized in that the wireless resource allocation system further includes: a controller, The controller includes a memory and a processor, which are communicatively connected to each other. The memory stores computer instructions, and the processor executes the computer instructions to perform the wireless resource allocation method according to any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the wireless resource allocation method according to any one of claims 1-5.

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