Resource allocation method based on potential game in VLC-wifi heterogeneous network

Abstract

The present application relates to a kind of resource allocation methods based on potential game in VLC-WiFi heterogeneous network, belong to optical wireless communication technical field.The method described in the present application makes all the VLC access points with overlapping coverage area use different color spectrum, and makes each user access the VLC or WiFi access point with strongest received power;VLC access point and WiFi access point respectively use the resource allocation algorithm based on proportional fair function and equal time resource, calculate the time resource factor of user, and calculate the satisfaction of all users according to time resource factor;Using the access point updating algorithm based on potential game to calculate the potential function value of all users accessing VLC or WiFi, user re-accesses the VLC or WiFi access point with greater potential function value;Calculate the average satisfaction of user in WiFi access point, if the average satisfaction of user is lower than the set threshold, then increase the value of fairness index, and repeat the above resource allocation step.The method described in the present application can improve the throughput of VLC-WiFi heterogeneous network and guarantee the satisfaction of user.

Description

Technical Field

[0001] This invention belongs to the field of optical wireless communication technology and relates to a resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks. Background Technology

[0002] Visible Light Communication (VLC) has garnered significant attention and research due to its advantages such as low power consumption, absence of electromagnetic interference, and no need for spectrum certification. VLC utilizes light-emitting diodes (LEDs) for signal transmission. Existing commercial LEDs offer various colors, including red, green, blue, and yellow, enabling the construction of multi-color VLC systems. To meet indoor lighting requirements, VLC networks often employ an access point layout with overlapping illumination ranges, leading to inter-cell interference and impacting system throughput. Multi-color LEDs, however, can utilize multi-color spectrum multiplexing to reduce the impact of inter-cell interference on users. At the receiver, filters can directly separate the signals, minimizing system complexity. Furthermore, single-color VLC networks suffer from weaknesses such as fragile optical links susceptible to blockage and difficulties in implementing uplinks. Existing research indicates that introducing Wireless Fidelity (WiFi) networks into VLC networks can compensate for these shortcomings and improve system throughput. However, heterogeneous networks employ different channel transmission models and possess varying network propagation characteristics. Most users accessing heterogeneous networks will be connected to WiFi access points, leading to uneven network load. Therefore, addressing the load problem between heterogeneous networks using resource allocation methods in VLC-WiFi heterogeneous networks is a key research focus. Summary of the Invention

[0003] The core of this invention lies in providing a resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks, which solves the problems of uneven load on access points and low resource utilization, thereby improving system throughput.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] The resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks includes the following steps:

[0006] S1: Define the user set, access point set, VLC access point set, and VLC multicolor spectrum set. Define the user request rate as C, the VLC access point transmission power as D, the WiFi access point transmission power as E, the average satisfaction threshold as m, the time period as T, the fairness index α as 0, and the fairness index increment l as F, with a value range of 0.1≤F≤0.5. Initialize the user set as {1,2,…,N}, the access point set as {0,1,…,A}, where 0 represents a WiFi access point, the VLC access point set as {1,2,…,A}, and the VLC multicolor spectrum set as { Red, green, blue, yellow}; VLC access points with overlapping coverage areas are configured using different multicolor spectra from the multicolor spectrum set. The channel gain from the user to the VLC access point is calculated based on the VLC Lambertian radiation model, and the channel gain from the user to the WiFi access point is calculated based on the Rayleigh fading channel model. The received power from the user to the VLC access point is obtained by multiplying the transmit power of the VLC access point by the channel gain from the user to the VLC access point, and the received power from the user to the WiFi access point is obtained by multiplying the transmit power of the WiFi access point by the channel gain from the user to the WiFi access point. The user selects the access point with the highest received power.

[0007] S2: VLC access points use a resource allocation algorithm based on the proportional fairness function to calculate the user's time resource factor, WiFi access points use a resource allocation algorithm based on equal time resource allocation to calculate the user's time resource factor, the user's channel capacity is calculated using the Shannon formula, the user's throughput is obtained by multiplying the time resource factor and the channel capacity, and the user's satisfaction is obtained by the ratio of the user's throughput to the request rate.

[0008] S3: Execute the access point update algorithm based on potential game for all users in the user set, calculate the potential function value of the user's access to VLC or WiFi, and reconnect the user to the VLC or WiFi access point with the larger potential function value.

[0009] S4: Calculate the average satisfaction of users within the WiFi access point, determine whether the average satisfaction of users within the WiFi access point is lower than the average satisfaction threshold m and whether α is less than 2. If so, make α = α + 1 and go to step S2; otherwise, end the algorithm.

[0010] Furthermore, the specific method of S1 is as follows:

[0011] S101: Let the user set be {1,2,…,N} and the user numbers be {1,2,…,N}. Let u = 1 and the fairness index increment l be F. Set the access points in the VLC access point set to be evenly distributed on the ceiling in an array, with their numbers increasing sequentially from left to right and from top to bottom. Starting from the access point with the smallest number, for VLC access points with non-overlapping coverage, randomly select a color spectrum from the multicolor spectrum set. For VLC access points with overlapping coverage areas, allocate a color spectrum from the multicolor spectrum set until all access points have been allocated a spectrum.

[0012] S102: Based on the Lambertian radiation model, calculate the user channel gain between user u and the VLC access point, and the channel gain of user u. The calculation formula is:

[0013]

[0014] Where A represents the receiving area of ​​the optical receiver, and the Lambertian radiation coefficient m = -ln2 / log2[cos(θ)] 1 / 2 )], θ 1 / 2 It is the half-power angle of the LED, d u θ is the straight-line distance between the LED and the u-th user. u and φ u These are the emission angle of the LED and the reception angle of the u-th user, respectively. FoV It is the field of view of the optical receiver, TS(φ) u ) is the gain of the optical concentrator, g(φ) u ) is the optical filter gain;

[0015] S103: Based on the Rayleigh fading model, calculate the user channel gain between user u and the WiFi access point, and the channel gain of user u. The calculation formula is:

[0016]

[0017] Where H0 represents the channel transfer function, which follows a standard Rayleigh distribution; X σ It is a Gaussian random variable with zero mean and a standard deviation of 10 dB; L(d u This represents the path loss of information transmitted by a WiFi access point after propagating through free space.

[0018] S104: The received power from the user to the VLC access point is obtained by multiplying the transmit power of the VLC access point by the channel gain from the user to the VLC access point. The received power from the user to the WiFi access point is obtained by multiplying the transmit power of the WiFi access point by the channel gain from the user to the WiFi access point. The access points are sorted in descending order of received power from user u to each access point. User u selects the access point with the highest received power. It is determined whether the user set has been traversed. If so, proceed to step S201; otherwise, u = u + 1 and proceed to step S102.

[0019] Furthermore, the specific method of S2 is as follows:

[0020] S201: The time resource factor for each user within each VLC access point is calculated using a resource allocation method based on the proportional fairness function. Specifically, when the fairness index is 0 and u' is the user with the largest channel capacity within AP i, the time resource factor for user u' is 1, and the time resource factors for the remaining users u within AP i are 0. When the fairness index is greater than 0, the calculation formula based on the proportional fairness function is as follows:

[0021]

[0022] Among them, a u,i δ is the time resource factor that VLC access point i allocates to user u. u α is the request rate of user u, α is the fairness index, K is the total number of users in the VLC access point, and R is the number of users in the VLC access point. u,i R is the channel capacity between user u and access point i. u,i =B i log(1+ξ u,i ), B i It is the multicolor spectrum bandwidth of access point i, B i =10MHz, ξ u,i It is the signal-to-noise ratio between user u and access point i. γ is the photoelectric conversion efficiency, γ = 0.53 A / W, P i It is the transmit power of VLC access point i. N is the channel gain between user u and access point i, and N0 is the VLC channel noise power spectral density, N0 = 1 × 10⁻⁶. -21 ;

[0023] S202: The time resource factor for users within the WiFi access point is calculated using a resource allocation algorithm based on equal time resource allocation. The calculation formula based on equal time resource allocation is as follows:

[0024]

[0025] Among them, a u,wη is the time resource factor allocated by the WiFi access point to user u, η is the maximum downlink transmission time of the WiFi access point, T-η is the uplink transmission time, η is set to 0.8 by default, and K is the total number of users in the WiFi access point.

[0026] S203: Calculate user satisfaction using the following formula:

[0027]

[0028] Where, θ u,i It represents the satisfaction level of user u within the VLC access point, θ u,w It is the satisfaction level of user u within the WiFi access point, R u,w R is the channel capacity between user u and access point i. u,w =B w log(1+ξ u,w ), B w It is the bandwidth of the WiFi access point, B w =20MHz, ξ u,w It is the signal-to-noise ratio between user u and the WiFi access point. P w It is the transmission power of the WiFi access point. N is the channel gain between user u and the WiFi access point. w It is the WiFi channel noise power spectral density, N w = -86dBm;

[0029] Furthermore, the specific method of S3 is as follows:

[0030] S301: Define all players in the player set of a potential game as all users in the user set. The utility of a user in a potential game is the user's satisfaction. A user's strategy in a potential game is to choose an access point from the set of access points. All strategies constitute the user's strategy set. Calculate the potential function value for a user accessing VLC or WiFi using the following formula:

[0031]

[0032] Among them, B u This is the current user's access policy, B. -u ={B1,B2,…,B u-1, B u+1 ,…,B Nu} represents the access point access policy for all users except user u, T u θ refers to other users within the same access point as user u. u (B -u B u ) represents user u's utility and user u's satisfaction. User u uses B u The strategy is an influencing factor on this access point, θ e (B -u B u ) represents the utility of user e when user u is at that access point. It is the utility of user e when user u is not at the access point;

[0033] S302: The user calculates the potential function value of the access point currently connected and counts the potential function values ​​of all access strategies. The user determines whether the access point with the largest potential function value is the access point connected by the current strategy. If so, the current state is maintained and the user is removed from the user set. Otherwise, the user selects the access point used by the strategy with the largest potential function value and the user is removed from the user set.

[0034] S303: Determine whether all users have been traversed. If yes, proceed to step S401; otherwise, select a new user from the remaining users in the user set and proceed to step S302.

[0035] Furthermore, the specific method of S4 is as follows:

[0036] S401: Calculate the average user satisfaction in the WiFi AP. The calculation formula is as follows:

[0037]

[0038] Where K is the total number of users within the WiFi access point, θ u,w It represents the satisfaction level of user u within the WiFi access point;

[0039] S402: Determine whether the average user satisfaction within the WiFiAP is lower than the user satisfaction threshold m and the value of α is less than 2. If so, make α = α + 1 and go to step S201; otherwise, end the algorithm.

[0040] The beneficial effects of this invention are as follows: This invention provides a resource allocation method based on potential game theory in an indoor VLC-WiFi heterogeneous network. First, VLC access points in overlapping indoor areas are assigned different multi-color spectrum resources, and users access the access point with the highest received power. Then, the VLC access points use a resource allocation algorithm based on a proportional fairness function to calculate the user's time resource factor, while the WiFi access points use a resource allocation algorithm based on equal time resource allocation to calculate the user's time resource factor. Finally, through an access point selection algorithm based on potential game theory, users rationally select access points for access based on potential function values, which can balance the load of each access point.

[0041] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will now be described in detail with reference to the figures, wherein:

[0043] Appendix Figure 1 Example diagram of downlink model in indoor multi-color VLC-WiFi heterogeneous network;

[0044] Appendix Figure 2 Example diagram of resource allocation method based on proportional fairness function in VLC access points

[0045] Appendix Figure 3 Flowchart of a potential game-based resource allocation method in VLC-WiFi heterogeneous networks;

[0046] Appendix Figure 4 Flowchart of the access point update algorithm based on potential game theory; Detailed Implementation

[0047] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0048] The figures are for illustrative purposes only and are schematic diagrams, not actual pictures, and should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some components in the figures may be omitted, enlarged, or reduced, and do not represent the actual product size. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the figures.

[0049] This invention calculates the time resource factor for each user in each VLC access point based on a resource allocation method using a proportional fairness function. Specifically, when the fairness index is 0 and u' is the user with the largest channel capacity within AP i, the time resource factor for user u' is 1, and the time resource factors for the remaining users u within AP i are 0. When the fairness index is greater than 0, the calculation formula based on the proportional fairness function is as follows:

[0050]

[0051] Where, δ u α is the request rate of user u, α is the proportional fairness index, K is the total number of users in the VLC access point, and R is the percentage of users. u,i R is the channel capacity between user u and access point i. u,i =B i log(1+ξ u,i ), B i It is the multicolor spectrum bandwidth of access point i, B i =10MHz, ξ u,i It is the signal-to-noise ratio between user u and access point i. γ is the photoelectric conversion efficiency, γ = 0.53 A / W, P i H is the transmit power of VLC access point i. u,i N is the channel gain between user u and access point i, and N0 is the VLC channel noise power spectral density, N0 = 1 × 10⁻⁶. -21 ;

[0052] This invention calculates the time resource factor for users within a WiFi access point based on a resource allocation algorithm that equally distributes time resources. The time resource factor a for user u is... u,w The calculation method is as follows:

[0053]

[0054] Where η is the maximum downlink transmission time of the WiFi access point, T-η is the uplink transmission time, η is set to 0.8 by default, and K is the total number of users within the WiFi access point; calculate the channel capacity R for user u within the WiFi access point. u,w R u,w =B w log(1+ξ u,w ), B w It is the bandwidth of the WiFi access point, B w =20MHz, ξ u,w It is the signal-to-noise ratio between user u and the WiFi access point. P w It is the transmit power of the WiFi access point, H u,w N is the channel gain between user u and the WiFi access point.w It is the WiFi channel noise power spectral density, N w = -86dBm;

[0055] This invention sets user satisfaction based on the user's obtained time resource factor and user demand rate. The method for calculating user satisfaction is as follows:

[0056]

[0057] Where, θ u,i It represents the satisfaction level of user u within the VLC access point, θ u,w It represents the satisfaction level of user u within the WiFi access point;

[0058] This invention calculates the average user satisfaction within a WiFi access point (AP) based on the ratio of total user satisfaction to the total number of users. The calculation method is as follows:

[0059]

[0060] Where K is the total number of users within the WiFi access point, θ u,w It represents the satisfaction level of user u within the WiFi access point;

[0061] This invention determines whether a user should switch based on the magnitude of the potential function value at each selected access point. The method for calculating the potential function value of user u is as follows:

[0062]

[0063] Among them, B u This is the current user's access policy, B. -u ={B1,B2,…,B u-1 B u+1 ,…,B Nu} represents the access point access policy for all users except user u, T u θ refers to other users within the same access point as user u. u (B -u B u ) represents user u's utility and user u's satisfaction. User u uses B u The strategy is an influencing factor on this access point, θ e (B -u B u ) represents the utility of user e when user u is at that access point. It is the utility of user e when user u is not at the access point.

[0064] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0065] Appendix Figure 1 This diagram illustrates a downlink model in an indoor multi-color VLC-WiFi heterogeneous network. VLC access points are arranged in an array on the ceiling, with overlapping coverage areas using different multi-color spectra. WiFi access points are placed in the center of the room. In this paper, visible light access points are primarily responsible for downlink signal transmission, while WiFi access points handle uplink signal transmission and some downlink signal transmission. All VLC and WiFi access points are connected to the same central controller. VLC or WiFi access points transmit resource allocation information to users via the downlink.

[0066] Appendix Figure 2 This is an example diagram of a resource allocation method based on the proportional fairness function in a VLC access point. Assuming the number of users N = 3, namely u1, u2, and u3, calculate the channel capacity R for each of the three users. 1,i R 2,i R 3,i The data are sorted in descending order according to channel capacity, and the time resource factor a for the three users is calculated according to formula (1). 1,i a 2,i a 3,i The time resource factors of the three users change with the fairness index α; the value of α is related to the average satisfaction of users within the WiFi network and is dynamically changing. To illustrate the dynamic nature of the fairness index α, examples are given for α = 0 and α = 0.5.

[0067] When α = 0, calculate the time resource factors for the three users. In this case, without considering fairness, allocate all time resources to the user with the largest channel capacity. If R... 1,i >R 2,i >R 3,i Then a 1,i =1, a 2,i =0, a 3,i =0, the resource allocation process is as follows: Figure 2 As shown in (a). When α = 0.5, calculate the time resource factor for the three users. At this time, the request rate of all users is C, and formula (1) can be simplified to: R 总 =R 1,i +R 2,i +R 3,i Therefore, The resource allocation process is as follows: Figure 2 As shown in (b).

[0068] Appendix Figure 3 This is a flowchart of a resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks, which will be explained in detail below:

[0069] Step 1: Define the user set, access point set, VLC access point set, and VLC multicolor spectrum set. Define the user request rate as C, the VLC access point transmission power as D, the WiFi access point transmission power as E, the average satisfaction threshold as m, the time period as T, the fairness index α as 0, and the fairness index increment l as F.

[0070] Step 2: Initialize the user set to {1,2,…,N}, the access point candidate user set to an empty set, the access point set to {0,1,…,A}, where 0 represents a WiFi access point, the VLC access point set to {1,2,…,A}, and the VLC multicolor spectrum set to {red,green,blue,yellow}.

[0071] Step 3: Set the access points in the VLC access point set to be evenly distributed on the ceiling in an array, with their sequence numbers increasing sequentially from left to right and from top to bottom. Starting from the access point with the smallest sequence number, for VLC access points with non-overlapping coverage, randomly select a spectrum of a color from the multicolor spectrum set. For VLC access points with overlapping coverage areas, assign different multicolor spectra from the multicolor spectrum set until all access points have been assigned spectrum.

[0072] Step 4: Initialize user ID u = 1. Calculate the channel gain from the user to all VLC access points in the VLC access point set using the VLC Lambertian radiation model, and calculate the channel gain from the user to the WiFi access point using the Rayleigh fading channel model. Calculate the received power from the user to all VLC access points in the VLC access point set by multiplying the channel gain by the transmit power of the VLC access point, and calculate the received power from the user to the WiFi access point by multiplying the channel gain by the transmit power of the WiFi access point. User u accesses the access point with the highest received power.

[0073] Step 5: Determine if u is equal to the total number of users N. If not, set u = u + 1 and go to step 4. If yes, calculate the channel gain value between the user and the VLC access point in each VLC access point, and sort the users in the access point in descending order of the channel gain value. Set the user with the strongest channel gain value in the access point as a premium user, and set the rest as ordinary users. Reconnect the ordinary users to the WiFi access point. Calculate the time resource factor obtained by the users in the VLC access point and WiFi access point according to formula (1) and formula (2) respectively, and calculate the satisfaction of all users according to formula (3).

[0074] Step 6: Execute the access point update algorithm based on potential game for all users in the user set. The user calculates the value of the potential function brought by all access strategies according to formula (5), and judges whether the one with the largest potential function value is still the access point accessed by the current strategy. If so, the current state is maintained; otherwise, the user selects the access point adopted by the strategy with the largest potential function value.

[0075] Step 7: Calculate the average user satisfaction in the current WiFi access point using formula (4), determine whether the average user satisfaction in the WiFi AP is lower than the user satisfaction threshold m and whether the value of α is less than 2. If so, make α = α + l and go to step S201; otherwise, end the algorithm.

[0076] Appendix Figure 4 This is a flowchart of the access point update algorithm based on potential game theory, which will be explained in detail below:

[0077] Step 1: Initialization. Define all players in the player set of a potential game as all users in the user set. The utility of a user in a potential game is the user's satisfaction. The strategy of a user in a potential game is to choose an access point from the set of access points. All strategies constitute the user's strategy set.

[0078] Step 2: Randomly select one player from the player pool;

[0079] Step 3: Calculate the potential function value of the player using the current strategy according to formula (5);

[0080] Step 4: Randomly select a strategy from the strategy set, calculate the player's potential function value when using the strategy, and then remove the strategy from the strategy set;

[0081] Step 5: Determine whether to traverse the strategy set. If yes, proceed to step 6; otherwise, proceed to step 4.

[0082] Step 6: Determine if the strategy with the largest potential function value is the current access strategy. If so, maintain the current state and remove the player from the player set, then proceed to Step 7; otherwise, access the access point adopted by the strategy with the largest potential function value and remove the player from the player set.

[0083] Step 7: Determine if all players in the player set have been visited. If so, end the access point update algorithm based on potential game theory. Otherwise, go to step 2.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks, characterized by: The method includes the following steps: S1: Define the user set, access point set, VLC access point set, VLC multicolor spectrum set, and define the user request rate as C, the VLC access point transmit power as D, the WiFi access point transmit power as E, the average satisfaction threshold as m, the time period as T, and the fairness index. The initial user set is {1,2,…,N}, the access point set is {0,1,…,A}, where 0 represents a WiFi access point, the VLC access point set is {1,2,…,A}, and the VLC multicolor spectrum set is {red, green, blue, yellow}. VLC access points with overlapping coverage areas are configured to use different multicolor spectra from the multicolor spectrum set. The channel gain from the user to the VLC access point is calculated based on the VLC Lambertian radiation model, and the channel gain from the user to the WiFi access point is calculated based on the Rayleigh fading channel model. The received power from the user to the VLC access point is obtained by multiplying the VLC access point's transmit power by the channel gain from the user to the VLC access point, and the received power from the user to the WiFi access point is obtained by multiplying the WiFi access point's transmit power by the channel gain from the user to the WiFi access point. The user selects the access point with the highest received power. S2: VLC access points use a resource allocation algorithm based on the proportional fairness function to calculate the user's time resource factor, WiFi access points use a resource allocation algorithm based on equal time resource allocation to calculate the user's time resource factor, the user's channel capacity is calculated using the Shannon formula, the user's throughput is obtained by multiplying the time resource factor and the channel capacity, and the user's satisfaction is obtained by the ratio of the user's throughput to the request rate. S3: Execute the access point update algorithm based on potential game for all users in the user set, calculate the potential function value of the user's access to VLC or WiFi, and reconnect the user to the VLC or WiFi access point with the larger potential function value. The specific method of S3 is as follows: S301: Define all players in the player set of a potential game as all users in the user set. The utility of a user in a potential game is the user's satisfaction. A user's strategy in a potential game is to choose an access point from the set of access points. All strategies constitute the user's strategy set. Calculate the potential function value for a user accessing VLC or WiFi using the following formula: ； Among them, B u This is the current user's access policy, B. -u = {B1, B2, …, B u-1, B u+1, …, B Nu } represents the access point access policy for all users except user u, T u These are other users within the same access point as user u. It is the utility of user u, and also the satisfaction of user u. User u uses B u The strategy is an influencing factor on this access point. It is the utility of user e when user u is at this access point. It is the utility of user e when user u is not at the access point; S302: The user calculates the potential function value of the access point currently connected and counts the potential function values ​​of all access strategies. The user determines whether the access point with the largest potential function value is the access point connected by the current strategy. If so, the current state is maintained and the user is removed from the user set. Otherwise, the user selects the access point used by the strategy with the largest potential function value and the user is removed from the user set. S303: Determine whether all users have been traversed. If yes, proceed to step S4; otherwise, select a new user from the remaining users in the user set and proceed to step S302. S4: Calculate the average satisfaction level of users within the WiFi access point, determine whether the average satisfaction level of users within the WiFi access point is lower than the average satisfaction threshold m, and determine... Is it less than 2? If so, then make If the condition is met, proceed to step S2; otherwise, terminate the algorithm.

2. The resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks as described in claim 1, characterized in that: The specific method of S1 is as follows: S101: Let the user set be {1,2,…,N} and the user numbers be {1,2,…,N}. Let u=1 and the fairness index increment be l. Set the access points in the VLC access point set to be evenly distributed on the ceiling in an array, with their numbers increasing sequentially from left to right and from top to bottom. Starting from the access point with the smallest number, for VLC access points with non-overlapping coverage, randomly select a color spectrum from the multicolor spectrum set. For VLC access points with overlapping coverage areas, allocate a color spectrum from the multicolor spectrum set until all access points have been allocated a spectrum. S102: Based on the Lambertian radiation model, calculate the user channel gain between user u and the VLC access point, and the channel gain of user u. The calculation formula is: ； Where A represents the receiving area of ​​the optical receiver, and the Lambertian radiation coefficient is... , It is the half-power angle of the LED. It is the straight-line distance between the LED and the u-th user. and These are the emission angle of the LED and the reception angle of the u-th user, respectively. It is the field of view of the optical receiver. It is the gain of the optical concentrator. It is the gain of the optical filter; S103: Based on the Rayleigh fading model, calculate the user channel gain between user u and the WiFi access point, and the channel gain of user u. The calculation formula is: ； Where H0 represents the channel transfer function, which follows a standard Rayleigh distribution; It is a Gaussian random variable with zero mean and a standard deviation of 10 dB; L(d u This represents the path loss of information transmitted by a WiFi access point after propagating through free space. S104: The received power from the user to the VLC access point is obtained by multiplying the transmit power of the VLC access point by the channel gain from the user to the VLC access point. The received power from the user to the WiFi access point is obtained by multiplying the transmit power of the WiFi access point by the channel gain from the user to the WiFi access point. The access points are sorted in descending order of received power from user u to each access point. User u selects the access point with the highest received power. It is determined whether the user set has been traversed. If so, proceed to step S201; otherwise, let u = u + 1 and proceed to step S102.

3. The resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks as described in claim 1, characterized in that: The specific method of S2 is as follows: S201: The time resource factor for each user within each VLC access point is calculated using a resource allocation method based on a proportional fairness function. Where the fairness index is 0 and... When the user is the user with the largest channel capacity in AP i, the user When the time resource factor is 1 and the time resource factors of the other users u within AP i are 0, the calculation formula based on the proportional fairness function is as follows when the value of the fairness index is greater than 0: ； in, It is the time resource factor that VLC access point i allocates to user u. It is the request rate of user u. This is a fairness index, where K is the total number of users within the VLC access point. It is the channel capacity of user u and access point i. B i It is the multicolor spectrum bandwidth of access point i, B i =10MHz, It is the signal-to-noise ratio between user u and access point i. , It is the photoelectric conversion efficiency. P i It is the transmit power of VLC access point i. It is the channel gain between user u and access point i. It is the noise power spectral density of the VLC channel. ; S202: The time resource factor for users within the WiFi access point is calculated using a resource allocation algorithm based on equal time resource allocation. The calculation formula based on equal time resource allocation is as follows: ； in, It is the time resource factor that the WiFi access point allocates to user u. This is the maximum downlink transmission time of the WiFi access point. This is the uplink transmission time. The default setting is 0.8, where K is the total number of users within the WiFi access point; S203: Calculate user satisfaction using the following formula: ； in, It is the satisfaction level of user u within the VLC access point. It is the satisfaction level of user u within the WiFi access point. It is the channel capacity of user u and access point i. B w It is the bandwidth of the WiFi access point, B w =20MHz, It is the signal-to-noise ratio between user u and the WiFi access point. P w It is the transmission power of the WiFi access point. It is the channel gain between user u and the WiFi access point. It is the noise power spectral density of the WiFi channel. .

4. The resource allocation method based on potential game theory in VLC-WiFi heterogeneous networks as described in claim 1. Its features are: The specific method of S4 is as follows: S401: Calculate the average user satisfaction in the WiFi AP. The calculation formula is as follows: ； Where K is the total number of users within the WiFi access point. It represents the satisfaction level of user u within the WiFi access point; S402: Determine whether the average user satisfaction level within the WiFi AP is lower than the user satisfaction threshold m and the value of α is less than 2. If so, make... Proceed to step S201; otherwise, terminate the algorithm.

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