An aas and star-ris assisted interference coordination method

Abstract

The application discloses an AAS and STAR-RIS assisted interference coordination method; by dividing users in a service area into inner sector users, interference sector users and outer sector users, obtaining regional service requirements corresponding to the inner sector, the interference sector and the outer sector; according to the regional service requirements, the system spectrum is divided into interference sector spectrum resources and non-interference sector spectrum resources; the AAS forms a first beam and a second beam, and adopts a first transmission mode of STAR-RIS assisting the interference sector and the outer sector, or a second transmission mode of STAR-RIS assisting the inner sector and the outer sector, and transmits user signals on different beams or different spectrum resources to corresponding regions; the interference sector users can be isolated from the inner sector users and the outer sector users in the frequency domain, while the spectrum multiplexing capability of the sectors is retained, the channel quality of the interference sector and the sector edge users is improved, so that the same frequency interference between the inner sector and the outer sector is reduced, the system coverage capability is enhanced, and the spectrum resource configuration is matched with the dynamic user service distribution.

Description

Technical Field

[0001] This invention relates to the field of wireless communication, and more particularly to an AAS and STAR-RIS-assisted interference coordination method. Background Technology

[0002] With the continuous growth in the number of wireless users and traffic, the contradiction between limited spectrum resources and ever-increasing communication demands is becoming increasingly prominent. To improve the spectrum utilization efficiency of cellular networks, active antenna systems can be used to adjust the vertical beam direction, dividing a traditional single sector into inner and outer sectors in the vertical dimension, and allowing the inner and outer sectors to reuse the same spectrum resources, thereby increasing the number of users and service capacity that can be served per unit bandwidth.

[0003] However, since it is difficult to completely separate the inner and outer sector beams in terms of spatial coverage, users may simultaneously receive both inner and outer sector signals within the coverage boundary area of ​​the two types of beams. When the inner and outer sectors reuse the same spectrum resources, strong co-channel interference is likely to occur in this boundary area, leading to a decrease in the user's signal-to-interference-plus-noise ratio, a reduction in transmission rate, and even communication interruption. Furthermore, when the total transmit power of the base station is limited, the inner and outer sector beams need to share the base station's transmit power. The transmit power achievable by a single beam may be lower than that of traditional single-sector transmission methods, especially since users in the outer sector are farther from the base station and experience greater path loss, easily leading to a decrease in outer sector coverage. Solving these problems solely by increasing transmit power or expanding the spectrum isolation range may reduce system energy efficiency or spectrum utilization efficiency.

[0004] Therefore, how to maintain the spectrum reuse capability of inner and outer sectors while isolating interference in the boundary area between inner and outer sectors, and how to enhance the channel quality in interference areas and edge areas using active antenna systems (AAS) and simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR-RIS), are urgent problems to be solved in vertical sectorization systems. Furthermore, user service requirements and spatial distribution are dynamic; using fixed spectrum allocation and fixed beam transmission methods is difficult to continuously adapt to the service load of different areas. Therefore, it is also necessary to adaptively configure spectrum resources, beam parameters, and STAR-RIS parameters according to the user service requirements of each area. Summary of the Invention

[0005] The following is an overview of the topics described in detail in this article.

[0006] The purpose of this application is to at least partially solve one of the technical problems existing in the related art. The embodiments of this application provide an AAS and STAR-RIS assisted interference coordination method and system.

[0007] An embodiment of this application provides an AAS and STAR-RIS-assisted interference coordination method, comprising:

[0008] Users within the service area are divided into inner sector users, interference zone users, and outer sector users, and the corresponding regional business requirements of the inner sector, interference zone, and outer sector are obtained.

[0009] Based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector, the available spectrum resources of the system are divided to obtain the spectrum resources of the interference zone and the spectrum resources of the non-interference zone.

[0010] Based on the user's region, the spectrum resources of the interference zone and the spectrum resources of the non-interference zone, the system selects either the first transmission mode or the second transmission mode, controls the active antenna system AAS to form the first beam and the second beam, and controls the transmission and reflection reconfigurable smart surface STAR-RIS to reflect and transmit the incident signal in order to send data to users in the inner sector, users in the interference zone and users in the outer sector.

[0011] The first transmission method is as follows: transmitting user data in the inner sector based on the first beam, transmitting user data in the interference zone and the outer sector based on the second beam, and controlling STAR-RIS to assist in the transmission of the interference zone and the outer sector; the second transmission method is as follows: transmitting user data in the interference zone based on the first beam, transmitting user data in the inner sector and the outer sector based on the second beam, and controlling STAR-RIS to assist in the transmission of the inner sector and the outer sector.

[0012] According to certain embodiments of this application, users within the service area are divided into inner sector users, interference zone users, and outer sector users, and the regional service requirements corresponding to the inner sector, interference zone, and outer sector are obtained, including:

[0013] Obtain user business needs and user distribution information for each user within the service area;

[0014] The users in the inner sector, the users in the interference zone, and the users in the outer sector are determined based on user distribution information, beam parameters, and received power.

[0015] The service requirements of users in the internal sector, the interference zone, and the external sector are statistically analyzed to obtain the corresponding regional service requirements for each region.

[0016] According to certain embodiments of this application, determining inner sector users, interference zone users, and outer sector users based on user distribution information, beam parameters, and received power includes:

[0017] Users in the interference area are determined based on the coverage of the inner and outer sector beams and user distribution information.

[0018] Alternatively, calculate the difference in received power between the inner sector reference beam and the outer sector reference beam received by the user, and determine the inner sector user, the interference zone user, and the outer sector user based on the difference in received power.

[0019] Alternatively, users in the interference zone can be determined based on user location, distance between user and base station, and azimuth or elevation angle of user relative to base station in user distribution information.

[0020] Alternatively, candidate interference zones can be determined based on user location, and users in the interference zone can be identified based on the difference in received power between the inner sector reference beam and the outer sector reference beam received by users within the candidate interference zones.

[0021] According to certain embodiments of this application, the available spectrum resources of the system are divided according to the regional service requirements corresponding to the inner sector, interference zone, and outer sector to obtain interference zone spectrum resources and non-interference zone spectrum resources, including:

[0022] The allocation ratio of spectrum resources in the interference zone and the non-interference zone is determined based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector. The available spectrum resources of the system are then allocated according to the allocation ratio to obtain the spectrum resources in the interference zone and the non-interference zone.

[0023] Alternatively, the equivalent spectrum resource requirements of the interference zone and the non-interference zone can be determined based on the regional service requirements and spectrum efficiency corresponding to the inner sector, interference zone, and outer sector. The available spectrum resources of the system can then be divided according to the equivalent spectrum resource requirements of the interference zone and the non-interference zone to obtain the spectrum resources of the interference zone and the non-interference zone.

[0024] According to certain embodiments of this application, when there is service demand in the interference zone, and there is also service demand in the inner or outer sector, the initial interference zone resource ratio is limited to a preset minimum ratio. and maximum proportion between.

[0025] According to certain embodiments of this application, the first transmission method and the second transmission method adopt the same STAR-RIS unit parameter model; when STAR-RIS supports independent configuration for different resource units, the STAR-RIS's first... Each unit in the resource unit The reflection coefficient on the surface is expressed as:

[0026]

[0027] STAR-RIS's Each unit in the resource unit The transmission coefficients on are expressed as follows:

[0028]

[0029] in, Indicates the first Each unit in the resource unit The reflection coefficient on Indicates the first Each unit in the resource unit Transmission coefficient on and These represent the reflection power coefficient and transmission power coefficient of the controllable unit, respectively. and These represent the reflection phase and the transmission phase, respectively.

[0030] For an ideal, lossless, energy-splitting STAR-RIS, the following conditions are met:

[0031]

[0032] as well as

[0033] .

[0034] According to certain embodiments of this application, the first transmission method includes the following steps:

[0035] The base station controls the active antenna system to form a first beam, and uses the non-interference zone spectrum resources through the first beam to send its data to users in the inner sector;

[0036] The base station controls the active antenna system to form a second beam, and uses the second beam to send its data to users in the interference zone using spectrum resources in the interference zone and to users in the outer sector using spectrum resources in the non-interference zone;

[0037] The base station or STAR-RIS controller determines the reflection and transmission parameters of STAR-RIS based on the channel information, service requirements, and second beam parameters of users in the interference zone and users in the outer sector, and sends first control information to STAR-RIS. STAR-RIS reflects and transmits the incident signal of the second beam according to the first control information to form a reflected beam pointing to the interference zone and a transmitted beam pointing to the outer sector.

[0038] According to certain embodiments of this application, the second transmission method includes the following steps:

[0039] The base station controls the active antenna system to form a first beam, and uses the spectrum resources of the interference area to send data to users in the interference area through the first beam;

[0040] The base station controls the active antenna system to form a second beam, and uses the non-interference zone spectrum resources through the second beam to send superimposed data of inner and outer sector users to inner sector users and outer sector users;

[0041] The base station or STAR-RIS controller determines the reflection and transmission parameters of STAR-RIS based on the location, channel information, service requirements, second beam parameters, and non-orthogonal transmission parameters of users in the inner and outer sectors, and sends second control information to STAR-RIS. STAR-RIS reflects and transmits the incident signal of the second beam according to the second control information to form a reflected beam pointing to the inner sector and a transmitted beam pointing to the outer sector.

[0042] According to certain embodiments of this application, after determining the basic coverage directions of the first and second beams, in order to maximize the total transmission rate of all users in the inner sector, interference zone, and outer sector, the user resource allocation, user transmission power, and STAR-RIS reflection and transmission parameters are solved while satisfying one or more of the following constraints: the upper limit of the base station's total transmit power, user scheduling constraints of spectrum resources in the interference zone, user scheduling constraints of the inner sector and outer sector on spectrum resources in the non-interference zone, resource allocation variables and transmit power variables, STAR-RIS reflection coefficient, transmission coefficient and energy constraints, and user minimum transmission rate constraints.

[0043] According to certain embodiments of this application, the base station determines candidate transmission parameters under the first transmission mode and the second transmission mode respectively, and selects the first transmission mode or the second transmission mode based on at least one performance indicator among the total system transmission rate, minimum user rate, number of users meeting service requirements, total transmission power or interference level.

[0044] The above scheme has at least the following beneficial effects: the base station obtains the user's service needs and user distribution, determines the inner sector, interference zone, and outer sector based on the coverage relationship of the inner and outer sector beams, and counts the user service needs of each area; according to the regional service needs, the system spectrum is divided into interference zone spectrum resources for use by users in the interference zone and non-interference zone spectrum resources for reuse by users in the inner and outer sectors; further, the AAS is controlled to form the first beam and the second beam, and the first transmission mode of the interference zone and outer sector is assisted by STAR-RIS, or the second transmission mode of the inner sector and outer sector is assisted by STAR-RIS. By configuring the reflection and transmission parameters of STAR-RIS, user signals on different beams or different spectrum resources are transmitted to the corresponding areas. This method enables users in the interference zone to be isolated from users in the inner and outer sectors in the frequency domain, while preserving the spectrum reuse capability between the inner and outer sectors. It also utilizes the spatial beamforming capability of AAS and the reflection and transmission capability of STAR-RIS to improve the channel quality of users in the interference zone and sector edge, thereby reducing co-channel interference between inner and outer sectors, enhancing system coverage, and matching spectrum resource allocation with dynamic user service distribution. Attached Figure Description

[0045] The accompanying drawings are used to provide a further understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0046] Figure 1 This is a flowchart illustrating the steps of the AAS and STAR-RIS-assisted interference coordination method.

[0047] Figure 2 This is a flowchart outlining the steps to determine the business needs of users in each region;

[0048] Figure 3 This is a flowchart illustrating the steps of the first transmission method;

[0049] Figure 4 This is a flowchart of the second transmission method;

[0050] Figure 5 This is a signaling interaction flowchart of the AAS and STAR-RIS assisted interference coordination methods. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0052] It should be noted that although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, or the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0053] Embodiments of this application provide an AAS and STAR-RIS-assisted interference coordination method.

[0054] The embodiments of this application will be further described below with reference to the accompanying drawings.

[0055] Reference Figure 1 AAS and STAR-RIS assisted interference coordination method, comprising the following steps:

[0056] Step S100: Divide users within the service area into inner sector users, interference zone users, and outer sector users, and obtain the regional service requirements corresponding to the inner sector, interference zone, and outer sector.

[0057] Step S200: Based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector, the available spectrum resources of the system are divided to obtain the spectrum resources of the interference zone and the spectrum resources of the non-interference zone.

[0058] Step S300: Based on the user's region, the spectrum resources of the interference zone and the spectrum resources of the non-interference zone, select the first transmission mode or the second transmission mode, control the active antenna system AAS to form the first beam and the second beam, and control the transmission and reflection reconfigurable smart surface STAR-RIS to reflect and transmit the incident signal to send data to the inner sector user, the interference zone user and the outer sector user.

[0059] The first transmission method is as follows: transmitting user data in the inner sector based on the first beam, transmitting user data in the interference zone and the outer sector based on the second beam, and controlling STAR-RIS to assist in the transmission of the interference zone and the outer sector; the second transmission method is as follows: transmitting user data in the interference zone based on the first beam, transmitting user data in the inner sector and the outer sector based on the second beam, and controlling STAR-RIS to assist in the transmission of the inner sector and the outer sector.

[0060] Reference Figure 2 For step S100, users within the service area are divided into inner sector users, interference zone users, and outer sector users. The corresponding regional service requirements for the inner sector, interference zone, and outer sector are obtained, including the following steps:

[0061] Step S110: Obtain user business needs and user distribution information for each user within the service area;

[0062] Step S120: Determine the users in the inner sector, the users in the interference zone, and the users in the outer sector based on the user distribution information, beam parameters, and received power.

[0063] Step S130: Calculate the service requirements of users in the inner sector, users in the interference zone, and users in the outer sector to obtain the corresponding regional service requirements for each region.

[0064] Specifically, the base station acquires service demand information and user distribution information for each user within its service area. Let the set of users within the service area be denoted as . ,in Indicates the number of users.

[0065] When users When a user has a data transmission requirement, the user sends a service request message to the base station. The service request message includes a user identifier and service requirement information, and optionally, user location information. The service requirement information includes at least one of the following: requested transmission rate, amount of data to be transmitted, maximum allowable latency, reliability requirements, and service priority.

[0066] In one implementation, user service requirements are represented by the requested transmission rate, denoted as . ,in Indicates user The requested transmission rate. In another implementation, the base station determines the transmission rate based on the amount of data to be transmitted by the user. and maximum allowable delay Determine user business needs, i.e. The base station can also determine user service requirements based on the amount of data to be transmitted in the user's cache, service priority, or historical service volume.

[0067] User distribution information includes at least one of the following: user location coordinates, distance between the user and the base station, and azimuth and elevation angles of the user relative to the base station. User distribution information can be represented as ,in Indicates the distance between the user and the base station. This indicates the user's azimuth angle relative to the base station. This indicates the user's pitch angle relative to the base station.

[0068] When a user service request message carries location information, the base station determines the user's distance, azimuth, and elevation angle based on the location information. When the user service request message does not carry location information, the base station performs wireless positioning or wireless sensing on the user based on the uplink pilot signal, reference signal, or other wireless signals sent by the user to obtain the user's distance, azimuth, and elevation angle relative to the base station.

[0069] Optionally, the base station predicts the user's location in the next scheduling cycle based on the user's historical location information and movement status. Service demand information and user distribution information can be updated according to changes in user status. The base station stores the service demand information and user distribution information of each user in association, as a basis for subsequently determining the user's region and the service demand of the statistical region.

[0070] For step S120, determining the inner sector users, interference zone users, and outer sector users based on user distribution information, beam parameters, and received power includes the following steps:

[0071] Users in the interference area are determined based on the coverage of the inner and outer sector beams and user distribution information.

[0072] Alternatively, calculate the difference in received power between the inner sector reference beam and the outer sector reference beam received by the user, and determine the inner sector user, the interference zone user, and the outer sector user based on the difference in received power.

[0073] Alternatively, users in the interference zone can be determined based on user location, distance between user and base station, and azimuth or elevation angle of user relative to base station in user distribution information.

[0074] Alternatively, candidate interference zones can be determined based on user location, and users in the interference zone can be identified based on the difference in received power between the inner sector reference beam and the outer sector reference beam received by users within the candidate interference zones.

[0075] Specifically, the base station determines the inner sector, the interference zone, and the outer sector based on the coverage areas of the inner sector beam and the outer sector beam, as well as the user distribution information obtained in step S110. The interference zone is the area where the effective coverage areas of the inner sector beam and the outer sector beam overlap, and the two beams may cause co-channel interference.

[0076] Assume the base station controls an active antenna system to form an inner sector reference beam and an outer sector reference beam. The inner sector reference beam is used to cover the inner sector, and the outer sector reference beam is used to cover the outer sector. For users... The base station obtains the received power of the user's inner sector reference beam and outer sector reference beam, respectively, denoted as... and The received power can be measured by the user and reported to the base station by the reference signals of the inner sector reference beam and the outer sector reference beam, or it can be determined by the base station based on at least one of the following: user location, channel estimation results, beamforming parameters, beam transmit power, and antenna pattern.

[0077] Base station calculates users The difference in received power between the inner sector reference beam and the outer sector reference beam .in, and These represent the inner sector reference beam received power and the outer sector reference beam received power, respectively, in decibels.

[0078] Let the preset power difference threshold be... .when At that time, it indicates that the inner sector reference beam is in the user's The received power at this location is significantly higher than the received power of the outer sector reference beam, and the base station will... Identified as an internal sector user;

[0079] when When, it indicates that the outer sector reference beam is in the user's The received power at that location is significantly higher than the received power of the inner sector reference beam, and the base station will... Identified as an external sector user;

[0080] when When, it indicates that the inner sector reference beam and the outer sector reference beam are in the user's When the received power is relatively close, users are prone to co-channel interference when reusing spectrum resources in inner and outer sectors. The base station will then... Users identified as being in the interference zone.

[0081] Optionally, to avoid classifying weakly covered users with low received power in both the inner and outer sector reference beams as users in interference zones, the base station can also set a minimum effective received power. When the user satisfy and At that time, the user Users identified as being in the interference zone.

[0082] In another implementation, the base station determines the interference zone based on the user's location, the distance between the user and the base station, and the user's azimuth or elevation angle relative to the base station. The base station pre-sets a distance range or elevation angle range corresponding to the boundary area between inner and outer sectors. When a user is within this range, the user is identified as a user in the interference zone.

[0083] In another implementation, the base station first determines candidate interference areas based on the user's location, and then determines the actual interference area user based on the difference in received power between the inner sector reference beam and the outer sector reference beam received by the user in the candidate interference area, thereby simultaneously considering the user's spatial location and the actual beam coverage.

[0084] The base station can periodically update the area to which each user belongs based on changes in user location, beam parameters, and received power.

[0085] For step S130, the base station, based on the inner sector user set, interference zone user set, and outer sector user set determined in step S120, statistically analyzes the service demands of users in each region to obtain the regional service demands corresponding to the inner sector, interference zone, and outer sector, respectively. Let the inner sector user set, interference zone user set, and outer sector user set be respectively... , and For users Their business needs This can be determined by step S110.

[0086] In one implementation, the base station sums up the service demands of users in each area to obtain the total service demand for each area.

[0087] User service requirements in the inner sector are represented as follows ,

[0088] User service requirements in the interference zone are represented as follows: ,

[0089] User service requirements in the outer sector are represented as ,

[0090] in , and These represent the total workload that the inner sector, interference zone, and outer sector need to handle within the current resource scheduling cycle.

[0091] The total user service demand in the three regions is expressed as follows: ,

[0092] When there are no users with business needs within a certain area, the business needs of users in that area are determined to be zero. For example, when the user set in the interference zone is empty, it is determined that... .

[0093] Optionally, when different users have different service priorities, the base station can weight user service demands according to the service priorities. The weighted business demand is represented as .in, Indicates user Business priority weights.

[0094] Accordingly, the weighted service requirements of the inner sector, interference zone, and outer sector are expressed as follows: , as well as .

[0095] In the subsequent resource allocation process, base stations can adopt unweighted regional service requirements or weighted regional service requirements that take into account user service priorities.

[0096] Base stations can update the service requirements for each region based on user service needs or changes in the region they belong to.

[0097] For step S200, based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector, the available spectrum resources of the system are divided to obtain the spectrum resources of the interference zone and the spectrum resources of the non-interference zone, including the following steps:

[0098] The allocation ratio of spectrum resources in the interference zone and the non-interference zone is determined based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector. The available spectrum resources of the system are then allocated according to the allocation ratio to obtain the spectrum resources in the interference zone and the non-interference zone.

[0099] Alternatively, the equivalent spectrum resource requirements of the interference zone and the non-interference zone can be determined based on the regional service requirements and spectrum efficiency corresponding to the inner sector, interference zone, and outer sector. The available spectrum resources of the system can then be divided according to the equivalent spectrum resource requirements of the interference zone and the non-interference zone to obtain the spectrum resources of the interference zone and the non-interference zone.

[0100] Specifically, the base station divides the available spectrum resources of the system according to the service requirements of the inner sector, the service requirements of the interference zone, and the service requirements of the outer sector determined in step S100, and obtains the spectrum resources of the interference zone and the spectrum resources of the non-interference zone.

[0101] Let the set of available spectrum resources of the system be . The total system bandwidth is The base station divides the system's available spectrum resources into interference zone spectrum resource sets. Non-interference zone spectrum resource set The spectrum resource sets in the interference zone and the spectrum resource sets in the non-interference zone do not overlap and together constitute the system's available spectrum resource set, i.e. and Let the bandwidth corresponding to the set of spectrum resources in the interference zone be... The bandwidth corresponding to the set of spectrum resources in the non-interference zone is ,have The spectrum resources in the interference zone are used to carry user data from the interference zone, while the spectrum resources in the non-interference zone are used to carry user data from both inner and outer sectors. Inner and outer sector users reuse the spectrum resources in the non-interference zone.

[0102] The base station obtains the internal sector service requirements in step S130. Interference zone business requirements external sector business needs Determine the ratio of spectrum resources in the interference zone to those in the non-interference zone.

[0103] In one implementation, the base station determines the bandwidth corresponding to the spectrum resources of the interference zone according to the proportion of service demand in the interference zone to the total service demand of the three zones, i.e.:

[0104]

[0105] The remaining bandwidth is then determined as the bandwidth corresponding to the spectrum resources in the non-interference zone, i.e.:

[0106]

[0107] In another implementation, the base station can also determine the equivalent spectrum resource requirements for each region based on the service demands and spectrum efficiency of each region. Let the spectrum efficiencies of the inner sector, interference zone, and outer sector be respectively... , and The equivalent spectrum resource requirements for each region are expressed as follows:

[0108]

[0109] Since users in the inner sector and users in the outer sector reuse the same non-interference zone spectrum resources through different beams, the equivalent spectrum resource requirements of the non-interference zone can be determined based on the equivalent spectrum resource requirements of the inner and outer sectors.

[0110] In one implementation, the equivalent spectrum resource requirement of the non-interference zone is expressed as:

[0111]

[0112] The base station determines the allocation ratio of the two types of spectrum resources based on the equivalent spectrum resource requirements of the interference zone and the non-interference zone:

[0113]

[0114] When the inner and outer sectors use non-orthogonal transmission, the base station can determine the equivalent spectrum resource requirements of the non-interference zone based on power allocation, achievable rate, and decoding conditions.

[0115] When the inner sector, interference zone, and outer sector employ the same or approximately the same spectral efficiency, and the inner and outer sectors can fully reuse the spectrum resources of the non-interference zone, the above division formula can be simplified to:

[0116]

[0117] Optionally, when there is service demand in the interference zone, and there is also service demand in the inner or outer sector, the base station will limit the initial resource ratio of the interference zone to a preset minimum ratio. and maximum proportion Between. Let the initial allocation ratio of spectrum resources in the interference zone be... Then, the division ratio after boundary constraints can be expressed as:

[0118]

[0119] Accordingly:

[0120]

[0121] By setting a minimum allocation ratio, basic spectrum resources can be reserved for users in the interference zone when the service demand in the interference zone is low but there are still users in the interference zone; by setting a maximum allocation ratio, it can be avoided that the interference zone occupies too much spectrum resources, resulting in insufficient non-interference zone spectrum resources available in the inner and outer sectors.

[0122] When the system employs orthogonal frequency division multiplexing (OFDM) or OFDM multiple access (OFDMA) transmission, the system's spectrum resources can consist of multiple subcarriers, resource blocks, or resource units. The base station determines the optimal spectrum based on calculated... and This determines the number of subcarriers or resource blocks allocated to the spectrum resources in the interference zone and the non-interference zone. Assume the system has a total of... The number of resource blocks in the interference zone can be expressed as:

[0123]

[0124] The number of resource blocks in the non-interference zone is expressed as:

[0125]

[0126] in, This indicates a rounding operation, which can be rounding to the nearest integer, rounding up, or rounding down, depending on the resource guarantee strategy. The base station will... One resource block was assigned to the interference zone spectrum resource set, and the remaining... Each resource block is assigned to the non-interference zone spectrum resource set.

[0127] When the service demand in the interference zone is zero or the user set in the interference zone is empty, the base station may not allocate spectrum resources in the interference zone and may use all or part of the system spectrum resources as spectrum resources in the non-interference zone. When both the service demand in the inner sector and the service demand in the outer sector are zero, the base station may use all or part of the system spectrum resources as spectrum resources in the interference zone.

[0128] Base stations can periodically update spectrum resources in interference and non-interference areas, and can also re-execute spectrum resource allocation when changes in regional service demand or regional spectrum efficiency exceed a preset threshold. If the update conditions are not met, the base station can continue using the current spectrum resource configuration.

[0129] For step S300, based on the user's region, the spectrum resources of the interference zone and the spectrum resources of the non-interference zone, a first transmission mode or a second transmission mode is selected, the active antenna system AAS is controlled to form a first beam and a second beam, and the transmission and reflection reconfigurable smart surface STAR-RIS is controlled to reflect and transmit the incident signal to send data to users in the inner sector, users in the interference zone and users in the outer sector.

[0130] In both the first and second transmission modes, the base station determines at least one of the following parameters for each transmission beam: beam pointing, beamwidth, antenna downtilt angle, transmit power, and beamforming parameters, based on the location of users in each area, service requirements, channel quality, and the deployment location of STAR-RIS. Specifically, the transmission beam that directly transmits data to the corresponding user area has its main coverage direction pointing towards that user area; the transmission beam that requires STAR-RIS-assisted transmission has its main illumination direction pointing towards STAR-RIS to provide the incident signal for STAR-RIS's reflection and transmission transmission. For multiple users within the same area, the base station can allocate different subcarriers, resource blocks, time slots, or other orthogonal resource units to them.

[0131] The first and second transmission methods use the same STAR-RIS unit parameter model; when STAR-RIS supports independent configuration for different resource units, the STAR-RIS's first... Each unit in the resource unit The reflection coefficient on the surface is expressed as:

[0132]

[0133] STAR-RIS's Each unit in the resource unit The transmission coefficients on are expressed as follows:

[0134]

[0135] in, Indicates the first Each unit in the resource unit The reflection coefficient on Indicates the first Each unit in the resource unit Transmission coefficient on and These represent the reflection power coefficient and transmission power coefficient of the controllable unit, respectively. and These represent the reflection phase and the transmission phase, respectively.

[0136] For an ideal, lossless, energy-splitting STAR-RIS, the following conditions are met:

[0137]

[0138] as well as

[0139] .

[0140] When STAR-RIS uses a unified parameter configuration, for any resource unit, we have: , , as well as .

[0141] Reference Figure 3 For the first transmission method, the following steps are included:

[0142] Step S311: The base station controls the active antenna system to form a first beam and uses the non-interference zone spectrum resources through the first beam to send data to users in the inner sector.

[0143] In step S312, the base station controls the active antenna system to form a second beam, and uses the second beam to send data to users in the interference zone and users in the outer sector using the non-interference zone spectrum resources.

[0144] In step S313, the base station or STAR-RIS controller determines the reflection and transmission parameters of STAR-RIS based on the channel information, service requirements, and second beam parameters of users in the interference area and users in the outer sector, and sends first control information to STAR-RIS. STAR-RIS reflects and transmits the incident signal of the second beam according to the first control information to form a reflected beam pointing to the interference area and a transmitted beam pointing to the outer sector.

[0145] In step S311, based on the non-interference zone spectrum resources determined in step S200, the base station controls the AAS to form a first beam pointing towards the inner sector, and transmits data to the users in the inner sector through the first beam. Furthermore, the base station allocates corresponding resource units to the users in the inner sector from the non-interference zone spectrum resource set.

[0146] In one implementation, for resource units belonging to the non-interference zone spectrum resource set The first beam carries the internal sector user data on this resource unit, which can be represented as:

[0147]

[0148] in, Indicates the first beam in the resource unit The transmitted signal on This indicates the user data of the inner sector carried on this resource unit. The transmitted signal carries the user data of the inner sector scheduled on this resource unit. The user data of the inner sector uses the non-interference area spectrum resources and is separated from the user data of the interference area in the frequency domain.

[0149] In step S312, the base station controls the AAS to form a second beam. The second beam carries user data from the interference area on the spectrum resources of the interference area, and carries user data from the outer sector on the spectrum resources of the non-interference area.

[0150] For resource units belonging to the spectrum resource set of the interference zone The second beam carries the scheduled user data from the interference zone on this resource unit; for resource units belonging to the non-interference zone spectrum resource set... The second beam carries the scheduled external sector user data on this resource unit. Therefore, the transmission signal of the second beam in the first transmission mode can be expressed as:

[0151] ;

[0152] in, Indicates the second beam in the resource unit The transmitted signal on and Representing resource units respectively The baseband transmission signal carries the scheduled interference area user data and the outer sector user data.

[0153] Users in the outer sector and those in the inner sector reuse the same non-interference zone spectrum resources in the frequency domain, and are distinguished in the spatial domain by the first and second beams. The main illumination direction of the second beam is pointed towards STAR-RIS, so as to provide the incident signal for STAR-RIS to perform reflection and transmission transmission of user data in the interference zone and user data in the outer sector.

[0154] In step S313, the base station or STAR-RIS controller determines the reflection and transmission parameters of STAR-RIS based on the channel information, service requirements, and second beam parameters of users in the interference zone and users in the outer sector, and sends control information to STAR-RIS. STAR-RIS reflects and transmits the incident signal of the second beam according to the control information, forming a reflected beam pointing towards the interference zone and a transmitted beam pointing towards the outer sector.

[0155] In one implementation, when STAR-RIS supports independent configuration for different spectrum resources, the base station configures reflection and transmission parameters for the spectrum resources in the interference zone and the non-interference zone respectively. This ensures that signals on the spectrum resources in the interference zone are primarily transmitted to users in the interference zone via reflection links, and signals on the spectrum resources in the non-interference zone are primarily transmitted to users in the outer sector via transmission links. Consequently, users in the interference zone receive data from the second beam reflected by STAR-RIS, and users in the outer sector receive data from the second beam transmitted through STAR-RIS.

[0156] The reflection coefficient, transmission coefficient, and energy constraint of STAR-RIS adopt the parameter model described in step 3. In the first transmission mode, the base station configures the reflection parameters of each STAR-RIS unit to enhance the reflected signal in the user direction of the interference area; and configures the transmission parameters of each STAR-RIS unit to enhance the transmitted signal in the user direction of the outer sector. The reflection power coefficient and transmission power coefficient are used to adjust the energy distribution between the reflection link in the interference area and the transmission link in the outer sector.

[0157] In another implementation, when STAR-RIS uses a unified parameter configuration for different spectrum resources, the base station jointly determines the reflection parameters and transmission parameters so that the reflection coverage area of ​​STAR-RIS includes the interference area and its transmission coverage area includes the outer sector.

[0158] Inner sector users receive inner sector user data transmitted by the first beam on the non-interference zone spectrum resources, while interference zone users receive interference zone user data reflected by STAR-RIS on the interference zone spectrum resources. Outer sector users receive outer sector user data transmitted by STAR-RIS on the non-interference zone spectrum resources. Thus, the first transmission method isolates the interference zone spectrum resources while enabling the inner and outer sectors to multiplex the non-interference zone spectrum resources, and utilizes STAR-RIS to enhance the transmission link between the interference zone and the outer sector.

[0159] Reference Figure 4 For the second transmission method, the following steps are included:

[0160] Step S321: The base station controls the active antenna system to form a first beam and uses the spectrum resources of the interference area to send data to users in the interference area through the first beam.

[0161] In step S322, the base station controls the active antenna system to form a second beam, and uses the non-interference zone spectrum resources through the second beam to send superimposed data of inner and outer sector users to inner sector users and outer sector users;

[0162] In step S323, the base station or STAR-RIS controller determines the reflection and transmission parameters of STAR-RIS based on the location, channel information, service requirements, second beam parameters, and non-orthogonal transmission parameters of the users in the inner and outer sectors, and sends second control information to STAR-RIS. STAR-RIS reflects and transmits the incident signal of the second beam according to the second control information to form a reflected beam pointing to the inner sector and a transmitted beam pointing to the outer sector.

[0163] For step S321, based on the interference zone spectrum resources determined in step S200, the base station controls the active antenna system to form a first beam and transmits data to users in the interference zone through the first beam. The base station allocates corresponding subcarriers, resource blocks, or resource units to each user in the interference zone from the interference zone spectrum resource set.

[0164] In one implementation, for resource units belonging to the interference zone spectrum resource set The first beam carries user data from the interference zone on this resource unit, which can be represented as:

[0165]

[0166] in, Indicates the first beam in the resource unit The transmitted signal on This indicates the user data in the interference zone carried on this resource unit.

[0167] The user data transmitted by the first beam uses only the spectrum resources of the interference zone, while the user data of the inner sector and the user data of the outer sector use the spectrum resources of the non-interference zone. Therefore, the user data of the interference zone is orthogonal to the user data of the inner sector and the user data of the outer sector in the frequency domain, which can reduce co-channel interference between users in the interference zone and users in the inner and outer sectors.

[0168] In this transmission method, the first beam directly covers the interference area without needing to be reflected or transmitted through STAR-RIS. The base station adjusts the first beam to match the interference area and reduce signal leakage into the inner and outer sectors.

[0169] In step S322, the base station controls the active antenna system to form a second beam and transmits inner sector user data and outer sector user data through the second beam on the non-interference zone spectrum resources. Inner sector users and outer sector users reuse the same non-interference zone spectrum resources and are carried by the second beam in a non-orthogonal manner. The main illumination direction of the second beam is towards STAR-RIS so that inner sector user data and outer sector user data can be transmitted via STAR-RIS.

[0170] The STAR-RIS-formed reflection link serves users in the inner sector, while the transmission link serves users in the outer sector. The base station can select at least one inner sector user and at least one outer sector user for pairing on the same non-interference zone resource unit, and transmit the paired user data in a non-orthogonal superposition manner.

[0171] For resource units belonging to the non-interference zone spectrum resource set The second beam carries both inner sector user data and outer sector user data non-orthogonally on the same resource unit. Therefore, the transmitted signal of the second beam in the second transmission mode can be expressed as:

[0172] ;

[0173] in, Indicates the second beam in the resource unit The transmitted signal on and These respectively represent the resource units The upper part carries the transmitted signal components of the scheduled inner sector user data and outer sector user data.

[0174] In one implementation, power-domain non-orthogonal multiple access transmission is employed. This applies to resource units belonging to the non-interference zone spectrum resource set. Internal sector users With external sector users Reusing this resource unit results in:

[0175] ;

[0176] in and These represent internal sector users. and external sector users The complex amplitude coefficient, and These represent internal sector users. and external sector users The data symbols are denoted as follows. The corresponding transmit powers are denoted as . and Paired users in resource units The power distribution on the surface satisfies:

[0177]

[0178] in, Indicates the second beam in the resource unit The available transmit power. The base station can determine the pairing relationship and power allocation based on the service needs of inner and outer sector users, end-to-end equivalent channel quality, minimum transmission rate, and decoding capability.

[0179] In a preferred embodiment, the base station allocates higher transmit power to users with weaker end-to-end equivalent channel quality. Users with stronger end-to-end equivalent channel quality employ serial interference cancellation, first decoding the data of another user and removing the data from the received signal, then decoding their own data. Users with weaker end-to-end equivalent channel quality can treat the data of another user as interference and directly decode their own data. When the end-to-end equivalent channel quality of an inner sector user is higher than that of an outer sector user, the inner sector user performs serial interference cancellation; when the end-to-end equivalent channel quality of an outer sector user is higher than that of an inner sector user, the outer sector user performs serial interference cancellation.

[0180] Alternatively, other non-orthogonal multiple access methods can be used. For multiple inner sector users and multiple outer sector users, the base station can divide the users into multiple user groups. Different user groups orthogonally use different non-interference area resource units, while inner sector users and outer sector users in the same user group non-orthogonally reuse the same resource units.

[0181] The main illumination direction of the second beam is pointed towards STAR-RIS to provide STAR-RIS with a non-orthogonal superimposed incident signal carrying user data from the inner sector and user data from the outer sector.

[0182] In step S323, the base station or STAR-RIS controller determines the STAR-RIS parameters based on the location of users in the inner and outer sectors, channel information, service requirements, second beam parameters, and non-orthogonal transmission parameters, and sends control information to the STAR-RIS. The STAR-RIS reflects and transmits the incident signal of the second beam according to the control information, forming a reflected beam pointing towards the inner sector and a transmitted beam pointing towards the outer sector.

[0183] Specifically, STAR-RIS reflects and transmits the non-orthogonal superimposed signals carried by the second beam on the non-interference zone spectrum resources. The reflected signal is transmitted to the inner sector user via a reflection link, and the transmitted signal is transmitted to the outer sector user via a transmission link. Since both the reflected and transmitted signals are generated by the non-orthogonal superimposed signals carried by the second beam, the inner and outer sector users decode their own data from the received signal according to the power allocation and decoding order determined by the base station.

[0184] The reflection coefficient, transmission coefficient, and energy constraint of STAR-RIS adopt the aforementioned parameter model. In the second transmission mode, the base station configures the reflection parameters of STAR-RIS to enhance the reflected signal in the user direction of the inner sector; and configures the transmission parameters of STAR-RIS to enhance the transmitted signal in the user direction of the outer sector. The reflection power coefficient and transmission power coefficient are used to adjust the energy distribution between the inner sector reflection link and the outer sector transmission link.

[0185] In one implementation, the base station jointly determines the STAR-RIS reflection parameters, STAR-RIS transmission parameters, second beam transmit power, non-orthogonal user power allocation, and decoding order based on the end-to-end equivalent channel quality of inner sector users and outer sector users, so that inner sector users and outer sector users meet the corresponding service requirements or minimum transmission rate.

[0186] Users in the interference zone receive interference zone user data transmitted by the first beam on the interference zone spectrum resources, while users in the inner sector and outer sector receive the reflected and transmitted signals of STAR-RIS on the non-interference zone spectrum resources, respectively. Thus, the second transmission method directly serves the interference zone using the first beam, and collaboratively serves the inner and outer sectors through the second beam and the reflection and transmission of STAR-RIS.

[0187] It should be noted that the base station can determine candidate transmission parameters for both the first and second transmission modes, and select either the first or second transmission mode based on at least one performance indicator among the following: total system transmission rate, minimum user rate, number of users meeting service requirements, total transmit power, or interference level. When the direct transmission link quality within the inner sector is good, but the interference zone and outer sector require STAR-RIS assistance, the base station can choose the first transmission mode; when the direct transmission link quality within the interference zone is good, but the inner and outer sectors require STAR-RIS assistance, the base station can choose the second transmission mode.

[0188] In one alternative implementation, after the spectrum resources of the interference area and the spectrum resources of the non-interference area have been determined in step S200, and the basic coverage directions of the first beam and the second beam have been determined in the manner described above in step S300, the base station can further jointly determine the user resource allocation, user transmit power, and STAR-RIS reflection and transmission parameters.

[0189] The following example uses the first transmission mode to obtain the transmission parameters for each user by maximizing the total transmission rate of all users in the inner sector, interference zone, and outer sector. This parameter determination method is only one example; the base station can also use preset rules, parameter lookup tables, block iteration, or other parameter determination methods to obtain the corresponding transmission parameters.

[0190] 1. Sets, channels, and optimization variables;

[0191] For users and resource units Define binary resource allocation variables in, Representing resource units Assigned to user , Representing resource units Not assigned to user .definition For base stations in resource units The above is for users The transmit power allocated to the data. When the same user uses the same power on all of its allocated resource units, it can be set to... .

[0192] Let the channel matrix from the base station to STAR-RIS be... Base station to user The direct channel is STAR-RIS to users The channel is The normalized beamforming vectors for the first and second beams are respectively... and ,satisfy In this optional embodiment, and The beamforming vector can be predetermined based on the location and coverage direction of each area. Alternatively, the base station can also use the beamforming vector as a parameter to be determined, and jointly determine it with user resource allocation, user transmit power, and STAR-RIS parameters.

[0193] 2. Equivalent channel and transmission rate for users in each region;

[0194] For internal sector users Its data is transmitted directly via the first beam on the non-interference zone spectrum resources. It is located in the resource unit. The desired signal gain on the signal can be expressed as:

[0195]

[0196] For users in the interference zone Its data is transmitted via a second beam on the spectrum resources in the interference zone and reaches the user primarily through the STAR-RIS reflection link. It is located in the resource unit. The equivalent signal gain on the signal can be expressed as:

[0197]

[0198] For external sector users Its data is transmitted via a second beam on non-interference zone spectrum resources and primarily reaches users through the STAR-RIS transmission link. It is located in resource units. The equivalent signal gain on the signal can be expressed as:

[0199]

[0200] The above expression considers both the direct link from the base station to the user and the auxiliary link from the base station to the user via STAR-RIS. When the direct link of a user can be ignored, the direct channel term can be deleted from the corresponding equivalent channel expression.

[0201] definition For users In resource unit The remaining interference power received by the beam may include beam leakage interference between the first and second beams, interference from other cells, or other interference that has not been completely eliminated; definition For users Noise power. User In resource unit The signal-to-interference-plus-noise ratio (SIR) is uniformly expressed as:

[0202]

[0203] When the residual interference between beams can be ignored, it can be set as follows: The aforementioned signal-to-interference-plus-noise ratio (SINR) degrades to a signal-to-noise ratio (SNR). Let the bandwidth corresponding to each resource unit be... Then the user The transmission rate can be uniformly expressed as:

[0204]

[0205] Among them, for users in the interference zone, there are For internal sector users and external sector users, there are .

[0206] 3. Joint optimization problem;

[0207] After determining the basic coverage directions of the first and second beams, in order to maximize the total transmission rate of all users in the inner sector, interference zone, and outer sector, the user resource allocation, user transmission power, and STAR-RIS reflection and transmission parameters are solved while satisfying one or more of the following constraints: the upper limit of the base station's total transmit power, user scheduling constraints of spectrum resources in the interference zone, user scheduling constraints of the inner sector and outer sector on spectrum resources in the non-interference zone, resource allocation variables and transmit power variables, STAR-RIS reflection coefficient, transmission coefficient and energy constraints, and user minimum transmission rate constraints.

[0208] In one implementation, the base station aims to maximize the total transmission rate for all users in the three areas by jointly determining resource allocation variables, user transmit power, and STAR-RIS reflection and transmission parameters. The optimization objective can be expressed as:

[0209]

[0210] The optimization objective satisfies the following constraints.

[0211] The total transmit power constraint for the base station is:

[0212]

[0213] The user scheduling constraints for spectrum resources in the interference zone are:

[0214]

[0215] The scheduling constraints for inner sector users and outer sector users on the spectrum resources in the non-interference zone are as follows:

[0216]

[0217] The resource allocation variable and the transmit power variable satisfy:

[0218]

[0219] The reflection coefficient, transmission coefficient, and energy constraints of STAR-RIS are constrained by the parameters mentioned above in step S300.

[0220] The minimum transmission rate constraint for each user is as follows:

[0221]

[0222] in, Represents the set of all resource allocation variables. Represents the set of all user transmit power variables. This indicates the maximum allowed transmission power of the base station. Indicates user The corresponding minimum transmission rate requirement.

[0223] 4. Parameter determination results and their execution;

[0224] After obtaining a feasible or preferred solution to the above optimization problem, the base station acquires the user scheduling results corresponding to each resource unit, the transmit power of each user, and the reflection and transmission parameters of STAR-RIS. The base station sends at least one scheduling information among resource unit identifiers, beam identifiers, modulation and coding schemes, and receive time slots to users in the inner sector, interference zone, and outer sector. It also sends at least one control information among reflection power coefficients, transmission power coefficients, reflection phase, transmission phase, the spectrum resources corresponding to the parameters, and the parameter effective time to STAR-RIS or its controller. Subsequently, the base station transmits user data according to the determined resource allocation and transmit power, and controls STAR-RIS to assist transmission according to the determined reflection and transmission parameters.

[0225] In other implementations, the objective function can be replaced with maximizing the weighted total transmission rate, maximizing the minimum user rate, or minimizing the total transmit power while satisfying the minimum user rate, depending on the actual application requirements. The changes to the objective function and solution method described above do not affect the area division, spectrum resource allocation, or the resource, beam, and STAR-RIS transmission correspondence in the first transmission mode defined in steps S100 to S300.

[0226] It should be noted that the second transmission method can also determine user resource allocation, user transmit power, and STAR-RIS reflection and transmission parameters by following the steps described above.

[0227] Reference Figure 5 The following describes a signaling interaction flow for implementing the aforementioned AAS and STAR-RIS assisted interference coordination methods. The devices participating in the signaling interaction include the base station, STAR-RIS, and multiple users located within the base station's service area. These multiple users are identified as inner sector users, interference zone users, or outer sector users according to step S100. The base station completes user service requirement acquisition, spectrum resource allocation, transmission parameter configuration, and user data transmission through signaling interaction with each user and STAR-RIS.

[0228] When a user has a data transmission requirement, the user sends a service request message to the base station. The service request message includes a user identifier and service requirement information, and optionally, user location information. The service requirement information includes at least one of the following: requested transmission rate, amount of data to be transmitted, maximum allowable latency, reliability requirements, and service priority.

[0229] When a service request message carries user location information, the user location information may include at least one of the following: user location coordinates, distance between the user and the base station, and azimuth and elevation angles of the user relative to the base station. When a service request message does not carry user location information, the base station can obtain user distribution information based on uplink pilot signals, reference signals, or other radio signals transmitted by the user.

[0230] Users located in the inner sector, interference zone, and outer sector can all send service request messages to the base station in the manner described above. When sending a service request message, the user's region may not yet be determined. After receiving the service request message and obtaining the user's distribution information, the base station will determine whether the user belongs to the inner sector, interference zone, or outer sector according to step S100.

[0231] The base station determines the area to which each user belongs based on the location information reported by each user or the user distance and orientation information obtained based on wireless positioning and wireless sensing, in accordance with step S120, and obtains the inner sector user set, the interference zone user set, and the outer sector user set.

[0232] Based on the service demand information of each user, the base station separately calculates the user service demands for the inner sector, interference zone, and outer sector. Subsequently, following step S200, the base station divides the system's available spectrum resources into interference zone spectrum resources and non-interference zone spectrum resources according to the user service demands of each area and the available regional spectrum efficiency. The interference zone spectrum resources are used to carry user data within the interference zone, while the non-interference zone spectrum resources are used to carry user data for both the inner and outer sectors.

[0233] Based on the user's region, the service requirements of each region, the spectrum resource allocation results, the user's channel quality, and the STAR-RIS deployment location, the base station adopts either the first transmission mode or the second transmission mode in step S300.

[0234] When the first transmission mode is used, the base station controls the first beam to send data to users in the inner sector, controls the second beam to carry user data in the interference area and user data in the outer sector, and controls STAR-RIS to reflect the corresponding signals in the second beam to the interference area and transmit them to the outer sector.

[0235] When the second transmission method is adopted, the base station controls the first beam to send data to users in the interference area, controls the second beam to non-orthogonally carry user data in the inner sector and user data in the outer sector, and controls STAR-RIS to transmit the reflected signal of the second beam to the inner sector and the transmitted signal to the outer sector.

[0236] The base station determines the transmission parameters for each user based on the selected transmission mode. The transmission parameters include wireless transmission parameters and STAR-RIS parameters. Wireless transmission parameters include at least one of the following: resource element identifier, time slot information, beam identifier, transmit power, modulation and coding scheme, user pairing relationship, and decoding order. STAR-RIS parameters include at least one of the following: reflection power coefficient, transmission power coefficient, reflection phase, transmission phase, the corresponding spectrum resource, and the parameter's effective time.

[0237] The base station sends corresponding scheduling information to users in the inner sector, users in the interference zone, and users in the outer sector, respectively. The scheduling information includes at least the spectrum resource information allocated to the corresponding user. Optionally, the scheduling information also includes at least one of the following: beam identifier, transmission time slot, modulation and coding scheme, power allocation information, and decoding order.

[0238] The base station also sends STAR-RIS control information to the STAR-RIS or STAR-RIS controller. The STAR-RIS control information includes the reflection and transmission parameters of each controllable unit of the STAR-RIS, enabling the STAR-RIS to form the corresponding reflection and transmission beams according to the selected transmission mode.

[0239] According to the wireless transmission parameters determined in step S300, the base station forms a first beam and a second beam via AAS, and transmits user data on the corresponding interference zone spectrum resources or non-interference zone spectrum resources. Simultaneously, the base station controls STAR-RIS to reflect and transmit the corresponding incident signals according to the received STAR-RIS control information.

[0240] Users in the inner sector, the interference zone, and the outer sector receive user data on the corresponding spectrum resources, beams, and time slots according to the scheduling information sent by the base station. When the second transmission mode is used and the inner sector user data and the outer sector user data are transmitted in a non-orthogonal manner, the corresponding users can also perform data decoding or serial interference cancellation according to the power allocation and decoding order indicated in the scheduling information.

[0241] The base station can periodically or when preset trigger conditions are met, re-execute at least one of the above steps based on changes in user service needs, user location, user region, user channel quality, or resource utilization, in order to update spectrum resource allocation, transmission mode, wireless transmission parameters, and STAR-RIS control parameters.

[0242] The above is a detailed description of the preferred embodiments of this application, but this application is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of this application, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A method for interference coordination assisted by AAS and STAR-RIS, characterized in that, include: Users within the service area are divided into inner sector users, interference zone users, and outer sector users, and the corresponding regional business requirements of the inner sector, interference zone, and outer sector are obtained. Based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector, the available spectrum resources of the system are divided to obtain the spectrum resources of the interference zone and the spectrum resources of the non-interference zone. Based on the user's region, the spectrum resources of the interference zone and the spectrum resources of the non-interference zone, the system selects either the first transmission mode or the second transmission mode, controls the active antenna system AAS to form the first beam and the second beam, and controls the transmission and reflection reconfigurable smart surface STAR-RIS to reflect and transmit the incident signal in order to send data to users in the inner sector, users in the interference zone and users in the outer sector. The first transmission method is as follows: transmitting user data in the inner sector based on the first beam, transmitting user data in the interference zone and the outer sector based on the second beam, and controlling STAR-RIS to assist in the transmission of the interference zone and the outer sector; the second transmission method is as follows: transmitting user data in the interference zone based on the first beam, transmitting user data in the inner sector and the outer sector based on the second beam, and controlling STAR-RIS to assist in the transmission of the inner sector and the outer sector.

2. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, Users within the service area are divided into inner sector users, interference zone users, and outer sector users. The corresponding regional service requirements for the inner sector, interference zone, and outer sector are then obtained, including: Obtain user business needs and user distribution information for each user within the service area; The users in the inner sector, the users in the interference zone, and the users in the outer sector are determined based on user distribution information, beam parameters, and received power. The service requirements of users in the internal sector, the interference zone, and the external sector are statistically analyzed to obtain the corresponding regional service requirements for each region.

3. The AAS and STAR-RIS assisted interference coordination method according to claim 2, characterized in that, Based on user distribution information, beam parameters, and received power, users in the inner sector, interference zone, and outer sector are identified, including: Users in the interference area are determined based on the coverage of the inner and outer sector beams and user distribution information. Alternatively, calculate the difference in received power between the inner sector reference beam and the outer sector reference beam received by the user, and determine the inner sector user, the interference zone user, and the outer sector user based on the difference in received power. Alternatively, users in the interference zone can be determined based on user location, distance between user and base station, and azimuth or elevation angle of user relative to base station in user distribution information. Alternatively, candidate interference zones can be determined based on user location, and users in the interference zone can be identified based on the difference in received power between the inner sector reference beam and the outer sector reference beam received by users within the candidate interference zones.

4. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, Based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector, the available spectrum resources of the system are divided to obtain the spectrum resources of the interference zone and the spectrum resources of the non-interference zone, including: The allocation ratio of spectrum resources in the interference zone and the non-interference zone is determined based on the regional service requirements corresponding to the inner sector, interference zone, and outer sector. The available spectrum resources of the system are then allocated according to the allocation ratio to obtain the spectrum resources in the interference zone and the non-interference zone. Alternatively, the equivalent spectrum resource requirements of the interference zone and the non-interference zone can be determined based on the regional service requirements and spectrum efficiency corresponding to the inner sector, interference zone, and outer sector. The available spectrum resources of the system can then be divided according to the equivalent spectrum resource requirements of the interference zone and the non-interference zone to obtain the spectrum resources of the interference zone and the non-interference zone.

5. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, When there is business demand in the interference zone, and there is also business demand in the inner or outer sector, the initial resource ratio of the interference zone will be limited to a preset minimum ratio. and maximum proportion between.

6. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, The first and second transmission methods use the same STAR-RIS unit parameter model; when STAR-RIS supports independent configuration for different resource units, the STAR-RIS's first... Each unit in the resource unit The reflection coefficient on the surface is expressed as: STAR-RIS's Each unit in the resource unit The transmission coefficients on the surface are expressed as follows: in, Indicates the first Each unit in the resource unit The reflectance coefficient on Indicates the first Each unit in the resource unit Transmission coefficient on and These represent the reflection power coefficient and transmission power coefficient of the controllable unit, respectively. and These represent the reflection phase and the transmission phase, respectively. For an ideal, lossless, energy-splitting STAR-RIS, the following conditions are met: as well as 。 7. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, The first transmission method includes the following steps: The base station controls the active antenna system to form a first beam, and uses the non-interference zone spectrum resources through the first beam to send its data to users in the inner sector; The base station controls the active antenna system to form a second beam, and uses the second beam to send its data to users in the interference zone using the spectrum resources of the interference zone and to users in the outer sector using the spectrum resources of the non-interference zone; The base station or STAR-RIS controller determines the reflection and transmission parameters of STAR-RIS based on the channel information, service requirements, and second beam parameters of users in the interference zone and users in the outer sector, and sends first control information to STAR-RIS. STAR-RIS reflects and transmits the incident signal of the second beam according to the first control information to form a reflected beam pointing to the interference zone and a transmitted beam pointing to the outer sector.

8. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, The second transmission method includes the following steps: The base station controls the active antenna system to form a first beam, and uses the spectrum resources of the interference area to send data to users in the interference area through the first beam; The base station controls the active antenna system to form a second beam, and uses the non-interference zone spectrum resources through the second beam to send superimposed data of inner and outer sector users to inner sector users and outer sector users; The base station or STAR-RIS controller determines the reflection and transmission parameters of STAR-RIS based on the location, channel information, service requirements, second beam parameters, and non-orthogonal transmission parameters of users in the inner and outer sectors, and sends second control information to STAR-RIS. STAR-RIS reflects and transmits the incident signal of the second beam according to the second control information to form a reflected beam pointing to the inner sector and a transmitted beam pointing to the outer sector.

9. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, After determining the basic coverage directions of the first and second beams, in order to maximize the total transmission rate of all users in the inner sector, interference zone, and outer sector, the user resource allocation, user transmission power, and STAR-RIS reflection and transmission parameters are solved while satisfying one or more of the following constraints: the upper limit of the base station's total transmit power, user scheduling constraints of spectrum resources in the interference zone, user scheduling constraints of the inner sector and outer sector on spectrum resources in the non-interference zone, resource allocation variables and transmit power variables, STAR-RIS reflection coefficient, transmission coefficient and energy constraints, and user minimum transmission rate constraints.

10. The AAS and STAR-RIS assisted interference coordination method according to claim 1, characterized in that, The base station determines candidate transmission parameters for the first transmission mode and the second transmission mode respectively, and selects the first transmission mode or the second transmission mode based on at least one of the following performance indicators: total system transmission rate, minimum user rate, number of users meeting service requirements, total transmission power, or interference level.

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