A spectrum resource allocation method based on blockchain technology

Abstract

The present invention belongs to the field of wireless communication technology, and specifically relates to a spectrum resource allocation method based on blockchain technology. The present invention can provide a spectrum allocation plan more quickly by querying a shared spectrum priority list in a short time by dividing the shared spectrum priorities of PAL users, and when the spectrum resources of a single PAL user cannot meet the needs of GAA users, the priority list can quickly collaborate with other PAL users to provide additional spectrum allocation plans, thereby improving the spectrum allocation efficiency and the utilization rate of spectrum resources; by dividing the spectrum access priorities of GAA users, the request conflict problem of GAA users can be solved to a certain extent, and an optimization method is proposed for the request conflict problem between GAA users at different priorities, further reducing the conflict rate of GAA user requests, improving the success rate of GAA user requests, and improving the efficiency of GAA user spectrum access.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications, and in particular relates to a spectrum resource allocation method based on blockchain technology. Background Art

[0002] Spectrum resources are limited. As the number of wireless services and user devices continues to grow at an alarming rate, dynamic spectrum sharing becomes particularly important. The Federal Communications Commission (FCC) has established the Citizen Broadband Radio Service (CBRS) to improve the spectrum utilization efficiency of the 3550-3700MHz band. In the CBRS system, there are three levels of users, namely: Primary service (such as US Navy radar and fixed satellite earth stations) Incumbents: have the highest priority and must ensure interference protection from other layers; Priority Access License (PAL) users: these users can access the 3550-3650MHz channel through bidding; the license allows the use of 10MHz channels in census areas for 3 years; they need interference protection from general authorized access users (GAA); General Authorized Access (GAA) users: GAA users are the lowest priority users; when no higher priority users use the channel, they can access the idle spectrum in the form of opportunistic spectrum access, and they must comply with SAS instructions to switch channels or stop operations to accommodate any higher priority users.

[0003] At present, the CBRS system dynamically allocates spectrum to users through a centralized spectrum access system (SAS). The management pressure of SAS increases with the number of CBSD devices. When blockchain technology is used to build a CBRS system, the management pressure of SAS can be effectively alleviated. However, since it takes time to update spectrum data on the blockchain, the spectrum data returned by SAS to GAA users may not be updated in time, which will lead to the failure of this spectrum access request. Summary of the invention

[0004] The present invention proposes a spectrum resource allocation method based on blockchain technology. By using the Channel feature of the Hyperledger Fabric structure as the main body of the system framework, Channel 1 has multiple PAL users, and Channel 2 has PAL users and multiple Domain Proxy. Through hierarchical management, the management pressure of SAS can be effectively reduced. By setting Priority-Groups with different priorities, GAA users are regrouped. When GAA users bid to enter the Priority-Group, a part of conflicting requests can be screened according to the group entry rule, and a conflict resolution method is designed for conflicting spectrum requests of users in different Priority-Groups. By judging the geographical location, the frequency band used, and the usage time, the usage time of the GAA users in the Priority-Group with a lower priority is modified to not conflict with the GAA users in the group with a higher priority. At the same time, it is ensured that the modified scheme does not affect the GAA users in this Priority-Group. The spectrum access scheme is optimized again, the management cost is saved, the success rate of spectrum access is improved, and the spectrum utilization rate is effectively improved.

[0005] The technical solution of the present invention is:

[0006] A spectrum resource allocation method based on blockchain technology is used in a spectrum sharing system. The spectrum sharing system is composed of a centralized spectrum access system SAS, a first channel and a second channel. In the first channel, priority is given to accessing licensed PAL users to build a PAL user alliance chain. In the second channel, a PAL user builds an alliance chain with multiple Domain Proxy nodes. Public PAL users in the first channel and the second channel are defined as T-PAL users. The T-PAL users are used to record the spectrum access priority of general authorized access GAA users and implement spectrum access management for GAA users according to the priority order. The spectrum resource allocation method is:

[0007] The PAL user in the first channel sends a spectrum usage information query request to the SAS, and the SAS returns the spectrum usage information query result to the PAL user;

[0008] The PAL user obtains the sharable spectrum information based on the spectrum usage information query result and sends it to the SAS. The SAS calculates and determines the priority of the PAL user to share the spectrum based on the sharable spectrum information. The SAS generates a priority list and informs the PAL users in the first channel.

[0009] GAA users in the second channel enter the Priority-Group through bidding, obtain the corresponding spectrum access priority and save the information on the alliance chain in the second channel;

[0010] The GAA user in the second channel sends a spectrum authorization request to the T-PAL user. When the spectrum requests of GAA users in different Priority-Groups conflict, the conflict optimization smart contract is executed;

[0011] The T-PAL user integrates the spectrum authorization requests of GAA users in the second channel and packages them into a local database. The T-PAL user gives a spectrum allocation strategy based on the priority list of PAL users sharing the spectrum.

[0012] PAL users in the first channel provide spectrum resources to GAA users in the second channel according to the spectrum allocation strategy, update their respective spectrum usage data to the alliance chain in the first channel and inform SAS;

[0013] The GAA user in the second channel performs spectrum access according to the spectrum allocation strategy forwarded by the T-PAL user.

[0014] Furthermore, the T-PAL user provides a specific method of spectrum allocation strategy based on the PAL user shared spectrum priority list generated by SAS calculation:

[0015] When the spectrum resources provided by the PAL user at the top of the priority list are greater than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user at the top of the list directly provides spectrum for the GAA user. After the PAL user at the top of the list has allocated all the spectrum, it needs to send its own sharable spectrum information to the SAS again. The SAS determines the priority of the PAL user's shared spectrum through calculation and updates the PAL user shared spectrum priority list.

[0016] When the spectrum resources provided by the PAL user at the top of the priority list are less than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user at the top of the list will provide its own allocatable spectrum to the GAA user, and the remaining part will be provided by the PAL user at the second top of the priority list. After the PAL user has allocated the spectrum, it is necessary to resend the sharable spectrum information to the SAS to update the spectrum sharing priority list.

[0017] Furthermore, the method for determining the spectrum access priority of the GAA user is:

[0018] The T-PAL node publishes the spectrum access priority to be auctioned and related information, including the starting price, starting time, deadline, and the limit on the number of users in the Priority-Group; GAA users participate in the auction and enter the Priority-Group according to their needs;

[0019] GAA users participating in the auction should indicate the frequency band, usage time and geographic location information they want to use during the registration phase, and then initiate a bid. The smart contract will compare all valid bids, determine the number of valid bids according to the restriction rules for entering the Priority-Group and the number of users, and allow the GAA users corresponding to the bids to join the Priority-Group. Among them, the restriction rules of the Priority-Group are: GAA user requests in the same Priority-Group can coexist, and the frequency band, usage time and distance between adjacent users required by the GAA user are judged. When a GAA user wins the auction, that is, when he obtains the right to enter the Priority-Group, these GAA users are labeled on the blockchain. Different labels correspond to different Priority-Groups to which this GAA user belongs. When a GAA user sends a spectrum query, it will also send a label query to confirm the Priority-Group to which the user belongs based on the information stored on the alliance chain in the second channel. The serial number of the label corresponds to the spectrum access priority of the GAA user.

[0020] Furthermore, the spectrum access management method of the T-PAL user to the GAA user is:

[0021] The GAA user who is about to apply for spectrum access sends a spectrum authorization request to the T-PAL user through each Domain Proxy node in the second channel; if the GAA user belongs to the first spectrum access priority, the T-PAL user directly returns the available spectrum information to the GAA user of the first spectrum access priority;

[0022] If the GAA user belongs to the second spectrum access priority, the T-PAL user triggers the smart contract to determine whether the access of the GAA user with the second spectrum access priority conflicts with the user with the first spectrum access priority. If not, the T-PAL user returns the available spectrum information to the GAA user with the second spectrum access priority. If yes, the conflict optimization smart contract is triggered to optimize the spectrum access plan of the user with the second spectrum access priority, and the plan is notified to the GAA user. If the user agrees to the optimization plan, T-PAL saves the optimized plan. If the user disagrees to modify the plan, a rejection signal is returned to the T-PAL user, and the T-PAL user discards the spectrum request.

[0023] If the GAA user belongs to the third spectrum access priority, the T-PAL user triggers the smart contract to determine whether the access of the GAA user with the third spectrum access priority conflicts with the GAA user with the first spectrum access priority and the GAA user with the second spectrum access priority. If not, the T-PAL user returns the available spectrum information to the GAA user with the third spectrum access priority. If so, the conflict optimization smart contract is triggered to optimize the spectrum access plan of the user with the third spectrum access priority, and the plan is notified to the GAA user. If the user agrees to the optimization plan, the T-PAL user saves the optimized plan. If the user disagrees to modify the plan, a rejection signal is returned to the T-PAL user, and the T-PAL user discards the spectrum request.

[0024] By analogy, the T-PAL user implements spectrum access management for the GAA user according to the spectrum access priority of the GAA user and according to the priority order.

[0025] Furthermore, the specific method of the conflict optimization smart contract is:

[0026] When GAA user requests in different Priority-Groups conflict, the alliance chain in the second channel executes the following smart contract: first, determine whether the conflicting request is a frequency band conflict. If so, determine whether the interference cannot allow the user requests to coexist based on the geographical location of the corresponding user of the conflicting request; if not, determine whether it is a user request usage time conflict. If so, suspend the conflicting transaction first, and then postpone the usage time of the conflicting request in the Priority-Group with a lower priority, and arrange the start time of the spectrum request of this user after the end time of the request with which it conflicts. Once the spectrum usage of the request with a higher priority ends, this request can be connected; notify the corresponding GAA user of the modified plan. If the user agrees to the modification, the optimized plan will be updated to the chain. If the user disagrees with the modification, the request will be invalidated.

[0027] The beneficial effect of the present invention is that the present invention provides a spectrum resource allocation method based on blockchain technology. The method further subdivides the CBSD device priority of the original CBRS system, thereby achieving a better allocation of spectrum resources. The present invention proposes a method for generating a spectrum allocation scheme through the spectrum priority of PAL users, a method for determining the spectrum access priority of GAA users, and a conflict optimization method for solving GAA user requests at different spectrum access priorities. By dividing the shared spectrum priority of PAL users, a spectrum allocation scheme can be provided more quickly by querying the shared spectrum priority list in a short time, and when the spectrum resources of a single PAL user cannot meet the needs of GAA users, the priority list can be used to quickly collaborate with other PAL users to provide additional spectrum allocation schemes, thereby improving the spectrum allocation efficiency and the utilization rate of spectrum resources; by dividing the spectrum access priority of GAA users, the request conflict problem of GAA users can be solved to a certain extent, and an optimization method is proposed for the request conflict problem between GAA users at different priorities, further reducing the conflict rate of GAA user requests, improving the success rate of GAA user requests, and improving the efficiency of GAA user spectrum access. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The spectrum resource allocation system model in the present invention is shown;

[0029] Figure 2 shows a system execution timing diagram in the present invention;

[0030] Figure 3 It shows the timing diagram of the GAA user auction entering the Priority-Group in the present invention;

[0031] Figure 4 The conflict optimization timing diagram of GAA user spectrum requests in different Priority Groups in the present invention is shown;

[0032] Figure 5 A bar chart showing the probability of GAA users agreeing to modification and the success rate of spectrum trading in the design solution of the present invention;

[0033] Figure 6 A histogram showing the number of GAA user requests and transaction success rate in the design solution of the present invention is shown. DETAILED DESCRIPTION

[0034] The present invention is described in detail below with reference to the accompanying drawings and simulation examples.

[0035] Figure 1The system model diagram designed for the present invention is to build a spectrum sharing system in a geographical area. The system consists of two channels of Hyperledger Fabric structure, wherein Channel 1 is a consortium chain composed of multiple PAL users, and Channel 2 is a consortium chain composed of T-PAL user nodes and multiple Domain Proxy nodes, wherein SAS is responsible for returning spectrum information to PAL users and generating a shared spectrum priority list, and the subsequent processes are all completed within the system; the PAL user nodes coexisting in Channel 1 and Channel 2 are recorded as T-PAL; GAA users in different Priority-Groups are selected by auction; GAA users issue spectrum access requests through Domain Proxy nodes, and Domain Proxy is a system that can manage multiple GAA users. T-PAL users are responsible for recording the spectrum access priority of GAA users and implementing spectrum access management for GAA users according to the priority order.

[0036] PAL users in Channel 1 will send spectrum usage information query requests to SAS, and SAS will return spectrum usage information query results to PAL users. PAL users send information such as the available spectrum usage range, the duration of shared spectrum usage, and interference margin to SAS. SAS determines the priority of PAL users' shared spectrum through calculations and generates a priority list of PAL users' shared spectrum. SAS will inform PAL users in Channel 1 of the generated priority list. When the spectrum access request of GAA users in Channel 2 reaches Channel 1, it can quickly give a spectrum allocation strategy based on the priority list of PAL users' shared spectrum. PAL users in Channel 1 synchronize their respective spectrum usage on the chain, and PAL users in Channel 1 have the function of allocating spectrum to GAA users.

[0037] Figure 2 It is a complete timing diagram of the design method of the present invention, which includes the following processes: the process of spectrum query between T-PAL users and SAS, the process of SAS generating a priority list of shared spectrum for PAL users, the process of PAL user alliance chain maintaining spectrum data, the process of GAA user spectrum access, the execution process of conflict optimization smart contracts and the process of PAL user alliance chain returning spectrum allocation plan.

[0038] The process of spectrum query between T-PAL users and SAS, and the process of SAS generating a priority list of shared spectrum for PAL users are as follows:

[0039] PAL users in Channel 1 will send spectrum usage information query requests to SAS, and SAS will return spectrum usage information query results to PAL users. PAL users send information such as the available spectrum usage range, the duration of shared spectrum usage, and interference margin to SAS. SAS determines the priority of PAL users' shared spectrum through calculation and generates a PAL user shared spectrum priority list. SAS informs PAL users in Channel 1 of the generated priority list. When the spectrum access request of GAA users in Channel 2 reaches Channel 1, it can quickly give a spectrum allocation strategy based on the PAL user shared spectrum priority list.

[0040] The process of maintaining spectrum data in the PAL user alliance chain is as follows:

[0041] The T-PAL user queries the PAL user shared spectrum priority list in Channel 1 and provides the following spectrum allocation scheme: when the spectrum resources provided by the PAL user at the top of the priority list are greater than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user directly provides the spectrum to the GAA user. After the PAL user allocates the spectrum, it will send information such as the scope of spectrum use that it can provide, the duration of use of the shared spectrum, and the interference margin to the SAS again. The SAS determines the priority of the PAL user's shared spectrum through calculation and updates the PAL user shared spectrum priority list; when the spectrum resources provided by the PAL user at the top of the priority list are less than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user provides the spectrum that it can allocate to the GAA user, and the insufficient part is provided by the PAL user at the second place in the priority list. After the PAL user allocates the spectrum, it needs to send relevant information to the SAS again to update the spectrum sharing priority list.

[0042] The process of GAA user spectrum access is:

[0043] GAA users send the spectrum access priority they want to the Domain Proxy node, and the Domain Proxy node participates in the auction of spectrum access priority according to the needs of GAA users. The GAA user who successfully bids will be attached with a label, and the label number corresponds to the spectrum access priority of the GAA user (that is, the GAA label number is 1, indicating that the GAA user has the first spectrum access priority); there can be multiple users with the same spectrum access priority, and GAA users with the same spectrum access priority can be members of CCG (Common Channel Group) and ICG (Interference Coordination Group). It is necessary to ensure that the spectrum access requests of GAA users with the same spectrum priority can coexist. The DomainProxy node notifies the GAA user of the auction results, and the GAA user who failed the auction can still participate in the next auction. The GAA user sends a spectrum query request to the T-PAL user, carrying information such as the frequency band used, the time of use, the geographical location, and the transmission power. The T-PAL user stores the user-related information obtained in the local database, and the T-PAL user returns the spectrum query result to the GAA user.

[0044] The GAA user who is about to apply for spectrum access sends a spectrum authorization request to the T-PAL user through each Domain Proxy node in Channel 2. If the GAA user belongs to the first spectrum access priority, the T-PAL user directly returns the available spectrum information to the GAA user with the first spectrum access priority. If the GAA user belongs to the second spectrum access priority, the T-PAL user triggers the smart contract to determine whether the access of the GAA user with the second spectrum access priority conflicts with the user with the first spectrum access priority. If not, the T-PAL user returns the available spectrum information to the GAA user with the second spectrum access priority; if so, the conflict optimization smart contract is triggered to optimize the spectrum access plan of the user with the second spectrum access priority and notify the GAA user of the plan. If the user agrees to the optimization plan, T-PAL saves the optimized plan; if the user disagrees to modify the plan, a rejection signal is returned to the T-PAL user, and the T-PAL user discards the spectrum request. If the GAA user belongs to the third spectrum access priority, the T-PAL user triggers the smart contract to determine whether the access of the GAA user with the third spectrum access priority conflicts with the GAA user with the first spectrum access priority and the GAA user with the second spectrum access priority. If not, the T-PAL user returns the available spectrum information to the GAA user with the third spectrum access priority. If yes, the conflict optimization smart contract is triggered to optimize the spectrum access plan of the third spectrum access priority user and notify the GAA user of the plan. If the user agrees to the optimization plan, the T-PAL user saves the optimized plan. If the user disagrees to modify the plan, a rejection signal is returned to the T-PAL user and the T-PAL user discards the spectrum request.

[0045] T-PAL users will package the spectrum authorization requests of GAA users and store them in the local database. T-PAL users in Channel 1 will query the PAL user shared spectrum priority list on the chain in Channel 1. PAL users in Channel 1 will quickly provide spectrum allocation plans based on the PAL user shared spectrum priority list. After obtaining the allocation plan, PAL users in Channel 1 update their respective spectrum usage data to the chain and send the relevant information to SAS. SAS updates the PAL user shared spectrum priority list through calculation and informs the PAL user. After receiving the spectrum allocation plan, the T-PAL user node forwards the plan to the Domain Proxy node. The Domain Proxy node notifies the GAA user of the spectrum access plan, and the GAA user executes the spectrum access according to the plan.

[0046] Figure 3The timing diagram of the GAA user entering the Priority-Group in the method is as follows: the T-PAL node publishes the spectrum access priority to be auctioned and related information, including the starting price, starting time, deadline, and the limit on the number of users in the Priority-Group; the GAA user participates in the auction and enters the Priority-Group according to demand. Among them, the factors that GAA users can choose to join the Priority-Group include: requirements for the use of frequency bands or usage time, requirements for spectrum access priority, etc.

[0047] GAA users participating in the auction should indicate the frequency band, usage time, and geographic location they want to use during the registration phase, and then initiate a bid. The smart contract will compare all valid bids, determine the number of valid bids according to the restriction rules for entering the Priority-Group and the number of users, and allow the GAA users corresponding to the bids to join the Priority-Group. Among them, the restriction rules of the Priority-Group mainly include: GAA user requests within the same Priority-Group can coexist, and factors such as the frequency band, usage time, and distance between adjacent users required by the GAA user need to be judged. When a GAA user wins the auction, that is, when he obtains the right to enter the Priority-Group, the blockchain will attach tags to these GAA users. Different tags correspond to different Priority-Groups to which this GAA user belongs. When a GAA user sends a spectrum query, it will also send a tag query to confirm the Priority-Group to which the user belongs based on the information stored on the alliance chain in Channel2.

[0048] The present invention stipulates that the validity period of a GAA user's auction entry into the Priority-Group is the usage time indicated by the GAA user when participating in the auction. After the use is completed, the Priority-Group will execute the smart contract to remove the expired GAA user from the Priority-Group, and the GAA user can still participate in subsequent auctions and re-enter the Priority-Group.

[0049] The execution process of the conflict optimization smart contract is:

[0050] Figure 4The timing diagram of executing the conflict optimization smart contract in the method of the present invention. When there is a conflict between GAA user requests in different Priority-Groups (the conflict is divided into frequency band conflict and time conflict), the alliance chain in Channel 2 executes the smart contract, first determining whether the conflicting request is a frequency band conflict, if so, then determining whether the interference cannot allow the user requests to coexist based on the geographical location of the corresponding user of the conflicting request; if not, then determining whether it is a user request time conflict, if so, first suspending the conflicting transaction, then postponing the use time of the conflicting request in the Priority-Group with a lower priority, and arranging the start time of the spectrum request of this user after the end time of the request with which it conflicts, once the spectrum use of the request with a higher priority ends, this request can be connected, and then the modified plan is notified to the GAA user, and if the user agrees to the modification, the optimized plan is updated to the chain, and if the user disagrees with the modification, the request is invalidated.

[0051] The spectrum sharing system built on a multi-Channel structure based on Hyperledger Fabric adopted in the present invention has the following technical features: the PAL alliance chain in Channel 1 is an alliance chain composed of multiple PAL users in various regions. When the PAL user queries the SAS for overall spectrum data, the spectrum management is converted into shared spectrum usage information among PAL users. Spectrum resources can be allocated to GAA users, and the PAL user shared spectrum priority list is jointly maintained. The alliance chain of T-PAL users and Domain Proxy nodes in Channel 2 is used to determine the spectrum access priority of GAA users and manage the spectrum access process of GAA users.

[0052] The present invention provides a specific implementation method of providing a spectrum allocation scheme according to the priority of PAL user shared spectrum: a T-PAL user queries a PAL user shared spectrum priority list in Channel 1, and provides a spectrum allocation scheme as follows: when the spectrum resources provided by the PAL user at the top of the priority list are greater than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user directly provides the spectrum to the GAA user. After the PAL user allocates the spectrum, it will send information such as the spectrum usage range that it can provide, the duration of use of the shared spectrum, and the interference margin to the SAS again. The SAS determines the priority of the PAL user shared spectrum by calculation and updates the PAL user shared spectrum priority list; when the spectrum resources provided by the PAL user at the top of the priority list are less than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user provides the spectrum that it can allocate to the GAA user, and the insufficient part is provided by the PAL user at the second place in the priority list. After the PAL user allocates the spectrum, it needs to send relevant information to the SAS again to update the spectrum sharing priority list.

[0053] The present invention provides a specific implementation method of an auction for GAA users to obtain spectrum access priority through auction: the T-PAL node publishes the corresponding spectrum access priority to be auctioned and related information, including the starting price, starting time, deadline, and the maximum number of GAA users that can be in the same priority; GAA users independently select the spectrum access priority to be auctioned according to their own needs for the use time of the frequency band, and participate in the corresponding auction. Users participating in the auction will initiate a bid for the spectrum access priority, and the smart contract will compare all valid bids, and determine the number of valid bids according to the spectrum access priority restriction rules set by the T-PAL user node and the number of GAA users to limit the spectrum access priority, and obtain the spectrum access priority. The GAA user who successfully bids will be attached with a label, and the label serial number corresponds to the spectrum access priority of the GAA user. This design stipulates that the validity period after the GAA user auctions and obtains the spectrum access priority is the use time of the frequency band indicated by the GAA user when participating in the auction. After the use is completed, the alliance chain in Channel 2 triggers the smart contract to clear the label serial number of the expired GAA user, and the GAA user can still participate in the subsequent auction to re-bid for the spectrum access priority.

[0054] The present invention provides a specific implementation process of a conflict optimization smart contract when a spectrum authorization request of a GAA user with a lower spectrum access priority conflicts with a GAA user request with a higher priority: when there is a conflict in GAA user requests belonging to different spectrum access priorities (the conflict is divided into a frequency band conflict and a time conflict), the alliance chain triggers the smart contract, firstly judging whether the conflicting request is a frequency band conflict, if so, judging whether the interference cannot allow the GAA user requests to coexist according to the geographical location of the corresponding user of the conflicting request; if not, judging whether the GAA user request is a time conflict, if so, suspending the conflicting transaction first, and then postponing the use time of the conflicting request of the GAA user with a lower spectrum access priority, so that the modified request has no conflict, and at the same time ensuring that the modified plan cannot affect other GAA users that originally belong to the same priority, and then notifying the GAA user of the modified plan, the user agrees to the modification, and the chain updates the optimized plan, if the user disagrees to the modification, the request is invalidated.

[0055] Next, the present invention will illustrate the performance of the proposed solution in combination with simulation results. In the method, the spectrum sharing between PAL users and GAA users is mainly considered. Based on the existing CBRS standard, multiple PAL users form a consortium chain in Channel1, and T-PAL users and multiple Domain Proxy nodes form a consortium chain in Channel2. The main function of Channel1 is to obtain all spectrum resources from SAS, and Channel2 is mainly responsible for the grouping process of Priority-Group of GAA users and the execution of spectrum access of GAA users. The purpose of setting up two channels is to reduce the management pressure of SAS and improve the efficiency of the spectrum sharing system. In the simulation, a specific number of GAA users are randomly generated. The GAA users carry information such as the use time interval, the use frequency band and the relative geographical location. In the process of GAA users entering the Priority-Group, the restriction rule is that the spectrum access requests of GAA users in the same Priority-Group can coexist. When GAA users enter different Priority-Groups, they enjoy the priority access rights to the spectrum of the Priority-Group. When multiple GAA users in different Priority-Groups simultaneously issue spectrum access requests, the conflict optimization smart contract will use their frequency band, usage time and geographic location information. The smart contract will first determine whether there is a conflict in the frequency band; if so, it will then determine whether the geographic location between the users exceeds the threshold (in the simulation, the relative geographic location range is 0-100, and the threshold is 35); if it does not exceed the threshold, it will then determine whether there is a conflict in usage time; if so, the smart contract will modify the usage time of the conflicting request in the Priority-Group with a lower priority to after the end time of the request that conflicts with it but has a higher spectrum access priority, and will ask the modified GAA user whether he agrees to the plan; if he agrees, the modified spectrum access plan will be executed. Different from the traditional method of discarding conflicting transactions, the smart contract designed in this embodiment will use the multi-layer information carried by the user to make judgments, and add a scheme for modifying the usage time for requests that have conflicts in usage time after judgment, thereby improving the success rate of spectrum access requests over a period of time.

[0056] During the simulation, in order to increase the feasibility of the design scheme, two comparison schemes were added. The first comparison scheme is to randomly generate user requests and enter the Priority-Group without screening; the second comparison scheme is to randomly generate user requests and enter the Priority-Group after screening, but when the GAA user spectrum requests conflict between different Priority-Groups, no conflict optimization is performed; the design scheme is to randomly generate user requests, enter the Priority-Group after screening, and optimize the conflicts between Priority-Groups.

[0057] Figure 5 The bar graph shows the relationship between the probability of GAA users agreeing to the modification plan and the transaction success rate. Figure 5 As can be seen in the figure, as the probability of GAA users agreeing to modify the plan increases, the transaction success rate is also increasing. When the probability of GAA users agreeing to modify the plan exceeds 0.5, the transaction success rate of the design plan exceeds that of the comparative plan 1. On the overall level, the transaction success rate of the design plan is higher than that of the comparative plan 2 (in this simulation, the number of randomly generated user requests is 225).

[0058] Figure 6 This is a randomly generated bar chart showing the relationship between the number of user requests and the transaction success rate. Figure 6 It can be seen that as the number of user requests increases, the transaction success rate of all solutions is decreasing. This is because the increase in the number of requests greatly increases the conflict rate between user requests. However, the design solution still has a higher transaction success rate than the comparison solution (in this simulation, the probability that the user agrees to modify the solution is 1).

Claims

1. A spectrum resource allocation method based on blockchain technology, used in a spectrum sharing system, characterized in that: The spectrum sharing system is composed of a centralized spectrum access system SAS, a first channel and a second channel. In the first channel, priority is given to licensed PAL users to build a PAL user alliance chain. In the second channel, a PAL user builds an alliance chain with multiple Domain Proxy nodes. The public PAL users in the first channel and the second channel are defined as T-PAL users; the T-PAL users are used to record the spectrum access priority of the general authorized access GAA users and implement spectrum access management for GAA users according to the priority order; the Domain Proxy node is a management system node that can manage one or more GAA users; the method for determining the spectrum access priority of the GAA user is: The T-PAL node publishes the spectrum access priority to be auctioned and related information, including the starting price, starting time, deadline, and the limit on the number of users in the Priority-Group; GAA users participate in the auction and enter the Priority-Group according to their needs; GAA users participating in the auction should indicate the frequency band, usage time and geographic location information they want to use during the registration phase, and then initiate a bid. The smart contract will compare all valid bids, determine the number of valid bids according to the restriction rules for entering the Priority-Group and the number of users, and allow the GAA users corresponding to the bids to join the Priority-Group. Among them, the restriction rules of the Priority-Group are: GAA user requests in the same Priority-Group can coexist, and the frequency band, usage time and distance between adjacent users required by the GAA user are judged. When a GAA user wins the auction, that is, when he obtains the right to enter the Priority-Group, these GAA users are labeled on the blockchain. Different labels correspond to different Priority-Groups to which this GAA user belongs. When a GAA user sends a spectrum query, it will also send a label query to confirm the Priority-Group to which the user belongs based on the information stored on the alliance chain in the second channel. The label serial number corresponds to the spectrum access priority of the GAA user. The spectrum resource allocation method is: The PAL user in the first channel sends a spectrum usage information query request to the SAS, and the SAS returns the spectrum usage information query result to the PAL user; The PAL user obtains the sharable spectrum information based on the spectrum usage information query result and sends it to the SAS. The SAS calculates and determines the priority of the PAL user's shared spectrum based on the sharable spectrum information and generates a PAL user shared spectrum priority list. The SAS informs the PAL users in the first channel of the generated priority list. GAA users in the second channel enter the Priority-Group through bidding, obtain the corresponding spectrum access priority and save the information on the alliance chain in the second channel; In the second channel, the GAA user sends a spectrum authorization request to the T-PAL user. When the spectrum requests of GAA users in different Priority-Groups conflict, the conflict optimization smart contract is executed; T-PAL users integrate the spectrum authorization requests of GAA users in the second channel and package them and store them in the local database. SAS informs the PAL users in the first channel of the generated priority list. When the spectrum access request of the GAA user in the second channel reaches the T-PAL user, the T-PAL user gives a spectrum allocation strategy based on the priority list of shared spectrum of PAL users. The specific method is as follows: when the spectrum resources provided by the PAL user at the top of the priority list are greater than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user at the top of the list directly provides the spectrum to the GAA user. After the PAL user at the top of the list has allocated the spectrum, it needs to send its own sharable spectrum information to SAS again. SAS determines the priority of the PAL user's shared spectrum through calculation and updates the PAL user's shared spectrum priority list. When the spectrum resources provided by the PAL user at the top of the priority list are less than the spectrum resources required by the GAA user received by the T-PAL user, the PAL user at the top of the list will provide its own allocatable spectrum to the GAA user, and the remaining part will be provided by the PAL user at the second top of the priority list. After the PAL user has allocated the spectrum, it is necessary to resend the sharable spectrum information to the SAS to update the spectrum sharing priority list; PAL users in the first channel provide spectrum resources to GAA users in the second channel according to the spectrum allocation strategy, update their respective spectrum usage data to the alliance chain in the first channel and inform SAS; The GAA user in the second channel performs spectrum access according to the spectrum allocation strategy forwarded by the T-PAL user.

2. According to a spectrum resource allocation method based on blockchain technology according to claim 1, it is characterized in that: The spectrum access management method for T-PAL users to GAA users is as follows: The GAA user who is about to apply for spectrum access sends a spectrum authorization request to the T-PAL user through each Domain Proxy node in the second channel; if the GAA user belongs to the first spectrum access priority, the T-PAL user directly returns the available spectrum information to the GAA user of the first spectrum access priority; If the GAA user belongs to the second spectrum access priority, the T-PAL user triggers the smart contract to determine whether the access of the GAA user with the second spectrum access priority conflicts with the user with the first spectrum access priority. If not, the T-PAL user returns the available spectrum information to the GAA user with the second spectrum access priority. If yes, the conflict optimization smart contract is triggered to optimize the spectrum access plan of the second spectrum access priority user, and the plan is notified to the GAA user; if the user agrees to the optimization plan, T-PAL saves the optimized plan; if the user disagrees to modify the plan, a rejection signal is returned to the T-PAL user, and the T-PAL user discards the spectrum request; If the GAA user belongs to the third spectrum access priority, the T-PAL user triggers the smart contract to determine whether the access of the GAA user with the third spectrum access priority conflicts with the GAA user with the first spectrum access priority and the GAA user with the second spectrum access priority. If not, the T-PAL user returns the available spectrum information to the GAA user with the third spectrum access priority. If yes, the conflict optimization smart contract is triggered to optimize the spectrum access plan of the third spectrum access priority user, and the plan is notified to the GAA user. If the user agrees to the optimization plan, the T-PAL user saves the optimized plan; if the user disagrees to modify the plan, a rejection signal is returned to the T-PAL user, and the T-PAL user discards the spectrum request. By analogy, the T-PAL user implements spectrum access management for the GAA user according to the spectrum access priority of the GAA user and according to the priority order.

3. According to a spectrum resource allocation method based on blockchain technology according to claim 2, it is characterized in that: The specific method of the conflict optimization smart contract is: When GAA user requests in different Priority-Groups conflict, the alliance chain in the second channel executes the following smart contract: First, determine whether the conflicting request is a frequency band conflict. If so, determine whether the interference cannot allow the user requests to coexist based on the geographical location of the corresponding user of the conflicting request; if not, determine whether it is a user request usage time conflict. If so, suspend the conflicting transaction first, and then postpone the usage time of the conflicting request in the Priority-Group with a lower priority, and arrange the start time of the spectrum request of this user after the end time of the request with which it conflicts. Once the spectrum usage of the request with a higher priority ends, this request can be connected; The modified plan will be notified to the corresponding GAA user. If the user agrees to the modification, the optimized plan will be updated to the chain. If the user disagrees with the modification, the request will be invalidated.

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