Resource allocation method, device and system applicable to URLLC system

Abstract

The present invention discloses a resource allocation method, device, and system suitable for a URLLC system. The resource allocation method comprises generating a reliability performance model based on a finite block length based on transmission parameters and resource allocation parameters; generating a delay performance model for a deterministic resource allocation method based on the transmission parameters and resource allocation parameters; constructing a URLLC resource allocation model with the goal of minimizing bandwidth and transmission power; and solving the URLLC resource allocation model by combining the reliability performance model and the delay performance model to obtain a resource allocation solution. The present invention can optimally determine resource allocation parameter settings that meet reliability and delay performance requirements.

Description

Technical Field

[0001] The present invention belongs to the field of ultra-reliable low-latency communications (URLLC), and in particular relates to a resource allocation method, device and system suitable for a URLLC system. Background Art

[0002] As a key scenario in modern cellular mobile communications, ultra-reliable low-latency communication (URLLC) provides machine users with ultra-low latency and ultra-reliable communication capabilities, ensuring the safe and efficient operation of industrial automation, intelligent transportation systems, vehicle networks, and telemedicine. Implementing ultra-reliable low-latency communication requires both ensuring communication reliability and meeting low-latency requirements. This paper considers resource allocation technologies that can guarantee the reliability and latency performance requirements of machine-user communications in URLLC systems.

[0003] Existing research on URLLC reliability can be divided into two main categories based on different models. The first category associates reliability with the signal-to-noise ratio (SNR), assuming that reliability is guaranteed as long as the SNR exceeds a specified threshold. The second category associates reliability with block length. Based on finite-length information theory, reliability is guaranteed as long as the encoded block length exceeds a specified threshold.

[0004] Existing research on URLLC latency performance can be divided into two categories based on the source of delay. The first category considers only physical layer delay, including transmission delay and retransmission delay. The second category considers more extensive delays, such as those caused by scheduling during the queuing process. Summary of the Invention

[0005] To address the above problems, the present invention proposes a resource allocation method, device, and system suitable for URLLC systems. Taking deterministic resource allocation into consideration, a fixed service opportunity is provided to each machine user within each scheduling cycle. In URLLC business scenarios requiring fast response and high load, the conflicts and interference caused by resource competition can be reduced, thereby improving business reliability and reducing overall communication delay.

[0006] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0007] In a first aspect, the present invention provides a resource allocation method applicable to a URLLC system, comprising:

[0008] Based on the transmission parameters and resource allocation parameters, a reliability performance model based on finite block length is generated;

[0009] generating a delay performance model of a deterministic resource allocation method based on transmission parameters and resource allocation parameters;

[0010] A URLLC resource allocation model is constructed with the goal of minimizing bandwidth and transmission power.

[0011] Combined with the reliability performance model and the delay performance model, the URLLC resource allocation model is solved to obtain a resource allocation solution.

[0012] In combination with the first aspect, optionally, the method for generating the reliability performance model includes:

[0013] Transport block length for different users , based on the calculation formula of the error probability boundary, the corresponding error probability boundary value is calculated ;

[0014] Based on the transmission block length of different users and the corresponding error probability boundary value Curve fitting is performed to generate a reliability performance model, wherein the input parameter of the reliability performance model is the transmission block length, and the output parameter is the error probability boundary value.

[0015] In combination with the first aspect, optionally, the calculation formula of the error probability boundary is obtained by the following method:

[0016] In a flat Rayleigh fading channel, the non-coherent reception technique is used to model the channel as ,in, Transmit symbol, transmit symbol From multiple AM ​​constellations Evenly selected from , , is the amplitude modulation order, which is a positive integer greater than 0; To receive symbols; is the normalized transmission power, which is equal to the ratio of the actual transmission power to the actual noise power; is the power-normalized noise, , represents a complex Gaussian distribution with mean 0 and variance 1; is the channel coefficient, , is the variance of the channel coefficient, which is a variable parameter;

[0017] Normalize the constellation's average power , and calculate the average signal-to-noise ratio of the transmission , , and then calculate the probability density function of the non-coherent received symbol , ,in, ;

[0018] Using random coding joint boundary technology, we can obtain the error probability boundary , ,in, and are the transmitting sequence and the receiving sequence respectively, is a uniformly randomly distributed variable, is the generalized information density, For the length of each message, use get in ,when hour, , is a free parameter, ;

[0019] make , combined with the probability density function , using the Gaussian approximation principle to obtain , , and then get the error probability boundary The calculation formula of error probability boundary The calculation formula is ,in, for function, , , , .

[0020] In combination with the first aspect, optionally, the method for generating the delay performance model includes:

[0021] For different scheduling interval lengths , based on the calculation formula of timeout probability, calculate the corresponding timeout probability ;

[0022] Based on different scheduling interval lengths and the corresponding timeout probability Curve fitting is performed to generate a delay performance model, wherein the input parameter of the delay performance model is the scheduling interval length, and the output parameter is the timeout probability.

[0023] In combination with the first aspect, optionally, the calculation formula of the timeout probability is obtained by the following method:

[0024] Set each user The duration of receiving time is service opportunities, is the transmission block length after user coding modulation, The symbol transmission rate of the physical layer; the basic allocation unit of time is set as time slot , , indicating that each time slot can complete Transmission of symbols;

[0025] Let the length of the scheduling period be Time slot, , after adopting deterministic resource allocation, each user has The service time is , ;

[0026] The message arrival interval follows the mean The negative exponential distribution of seconds, the average number of messages arriving in a time slot is , Arrived within time slot The message arrival probability of a message is , ;

[0027] The number of messages in the user buffer after each service opportunity is defined as a state variable ,make Indicates the slave state : To status : The steady-state transition probability of and is a non-negative integer;

[0028] ;

[0029] Steady-state transition probability is a state variable The state transition probability matrix The constituent elements of the state transition probability matrix Substitute into the formula , calculate the steady-state probability vector ; Steady-state probability vector The elements in the symbol express, Status : The steady-state probability of is a non-negative integer;

[0030] The number of delay slots experienced by any message is The delay probability is , using the above steady-state probability vector and message arrival probability Analyze the delay probability in three cases :

[0031] Case 1: hour, ;

[0032] Case 2: hour, ,in, , is any non-negative integer, , ;

[0033] Case 3: hour, ,in:

[0034] ;

[0035] Where, , is any non-negative integer, is the channel coefficient, , is the variance of the channel coefficient, which is a variable parameter; , calculate the timeout probability exceeding the maximum delay D .

[0036] In combination with the first aspect, optionally, the objective function of the URLLC resource allocation model is:

[0037]

[0038] The constraints of the URLLC resource allocation model are:

[0039]

[0040] Among them, the first and second sets of constraints require users to The reliability and delay performance meet the needs of URLLC communication; the third and fourth groups of constraints limit the user Transmission power and sub-channel The scheduling cycle length Only discrete sets and The values ​​in , and the sizes of the two sets are and ; The fifth set of constraints is user Number of time slots occupied by message transmission Set a cap ; The fifth set of constraints uses associated parameters Restricted users Can only communicate with one subchannel of association; is the total number of sub-channels; is the lower bound of the achievable error probability; For users The error probability bound; is the tolerable timeout probability, For users The timeout probability, For users after adopting deterministic resource allocation In the cycle Service time within.

[0041] In combination with the first aspect, optionally, solving the URLLC resource allocation model in combination with the reliability performance model and the delay performance model to obtain a resource allocation scheme includes:

[0042] For each user and possible transmission power sets , transmission power set There are power elements, according to the reliability performance model , obtain a set of transmission block lengths that meet reliability requirements, and generate a time slot vector based on the transmission block length set , time slot vector There are time slot elements;

[0043] For each user and time slot vector , according to the delay model , obtain the scheduling cycle length vector that meets the delay performance requirements , scheduling cycle length vector There are The scheduling period length element;

[0044] For each user and scheduling cycle vector , to schedule the cycle vector The mean of is used as the metric, and the labels of K users are stored in the set in ascending order of the metric value. ;

[0045] Repeat the following steps for each sub-channel until the set All users in are allocated resources:

[0046] will be collected The first user in Add subchannel l and define the scheduling period of subchannel l at different power levels for , the user Power set , time slot vector And the corresponding scheduling cycle Composing a set of resource allocation plans ;

[0047] Continue adding sets for subchannel l Next user in , and the user Power set , time slot vector Add to resource allocation plan set , the scheduling period of subchannel l Each element is updated to its original With users Scheduling cycle The minimum value in the corresponding element is repeated until the time slot resources in one scheduling cycle of subchannel l are exhausted;

[0048] Taking power consumption as the metric, select the resource allocation scheme with the minimum metric for subchannel l.

[0049] In combination with the first aspect, optionally, the resource allocation scheme includes transmission power, transmission block length, bandwidth, association parameters between users and subchannels, scheduling period, and service duration of the user in each period.

[0050] In a second aspect, the present invention provides a resource allocation device applicable to a URLLC system, comprising:

[0051] A reliability performance model generation module, configured to generate a reliability performance model based on a finite block length based on transmission parameters and resource allocation parameters;

[0052] A delay performance model generation module, configured to generate a delay performance model of a deterministic resource allocation method based on transmission parameters and resource allocation parameters;

[0053] A URLLC resource allocation model construction module is used to construct a URLLC resource allocation model with the goal of minimizing bandwidth and transmission power;

[0054] The resource allocation module is used to solve the URLLC resource allocation model by combining the reliability performance model and the delay performance model to obtain a resource allocation solution.

[0055] In a third aspect, the present invention provides a resource allocation system applicable to a URLLC system, comprising a storage medium and a processor;

[0056] The storage medium is used to store instructions;

[0057] The processor is configured to operate according to the instructions to execute the method according to any one of the first aspects.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] 1. At the transmission reliability level, the present invention establishes a finite transmission block length model, taking into account the limitations brought about by factors such as transmission delay and data packet size in actual communication systems, thereby reducing system complexity while ensuring system communication reliability.

[0060] 2. At the low-latency transmission level, the present invention proposes a deterministic resource allocation method, which can reduce conflicts and interference caused by resource competition in the communication system, reduce the overall communication delay, and at the same time reduce the system complexity by eliminating the need for dynamic signaling overhead. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work, among which:

[0062] Figure 1 is a flow chart of a resource allocation method provided by an embodiment of the present invention;

[0063] Figure 2 is a system architecture diagram provided by an embodiment of the present invention;

[0064] Figure 3 This is an example diagram of resource allocation provided by an embodiment of the present invention;

[0065] Figure 4 is an example diagram of a queuing model provided by an embodiment of the present invention;

[0066] Figure 5 is a schematic diagram of a cumulative distribution function of a transmission error probability provided by an embodiment of the present invention;

[0067] Figure 6 Schematic diagram of the cumulative distribution function of the delay timeout probability provided by an embodiment of the present invention;

[0068] Figure 7 1 is a schematic diagram comparing sub-channel consumption when the number of users is changed between the method provided by an embodiment of the present invention and a control method;

[0069] Figure 8 This is a schematic diagram of sub-channel consumption when the number of users and delay performance requirements are changed according to an embodiment of the present invention;

[0070] Figure 9 This is a schematic diagram of sub-channel consumption when the number of users and reliability performance requirements are changed, provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0071] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0072] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0073] Example 1

[0074] An embodiment of the present invention provides a resource allocation method applicable to a URLLC system, comprising the following steps:

[0075] Based on the transmission parameters and resource allocation parameters, a reliability performance model based on finite block length is generated;

[0076] generating a delay performance model of a deterministic resource allocation method based on transmission parameters and resource allocation parameters;

[0077] A URLLC resource allocation model is constructed with the goal of minimizing bandwidth and transmission power.

[0078] Combined with the reliability performance model and the delay performance model, the URLLC resource allocation model is solved to obtain a resource allocation solution.

[0079] Consider Figure 2 The specific process of the deterministic resource allocation method applicable to the URLLC system in the embodiment of the present invention can be referred to Figure 1 , including the following steps:

[0080] S1: Set transmission parameters and resource allocation parameters;

[0081] S2: generating a reliability performance model based on a finite block length based on the transmission parameters and resource allocation parameters;

[0082] S3: generating a delay performance model of a deterministic resource allocation method based on the transmission parameters and resource allocation parameters;

[0083] S4: Construct a URLLC resource allocation model with the goal of minimizing bandwidth and transmission power;

[0084] S5: Combine the reliability performance model and the delay performance model to solve the URLLC resource allocation model and obtain a resource allocation scheme. The resource allocation scheme includes resource parameter settings such as transmission power, block length, user scheduling, and bandwidth and time allocation.

[0085] like Figure 2 As shown, the URLLC system in the present invention includes a base station and distributed around the base station. Each machine user has a message to transmit to the base station and communicates according to the specified transmission parameters and resource allocation parameters. The transmission parameters can be described as follows: Assume that the length of each message of each user is , the modulation order is , the transmission block length after coding modulation is , the average signal-to-noise ratio of transmission is Since the block length is limited, errors may occur during the transmission of the message. is the lower bound of the error probability achievable by the user.

[0086] The resource allocation parameters can be described as follows: Assuming that the user's message arrival interval follows the mean The negative exponential distribution of the user's delay requirement can be expressed as ,in, The delay experienced by the user's message, For the maximum delay requirement, is the probability of delay exceeding the maximum delay that the user can tolerate.

[0087] like Figure 3 As shown, the total number of sub-channels divided by the present invention is , the bandwidth of each subchannel is Hertz. Subchannel The time axis is divided into continuous and equal-length scheduling periods ,user Can only communicate with one subchannel Associated. is the symbol transmission rate of the physical layer, , each scheduling cycle A fixed position is reserved for each user for a period of service opportunity, which is long enough for the user to send a message.

[0088] The specific method for establishing the finite block length reliability performance model in step S2 can be divided into the following three steps:

[0089] First, in a flat Rayleigh fading channel, the non-coherent reception technique is used to model the channel as , where the transmission symbol From multiple AM ​​constellations Evenly selected from , , To receive symbols, is the normalized transmission power, which is equal to the ratio of the actual transmission power to the actual noise power; is the power-normalized noise, ; is the channel coefficient, . Normalize the constellation's average power , calculate the average signal-to-noise ratio of the transmission , From this, the probability density function of the non-coherent received symbol can be calculated: ,in .

[0090] Then, the random coding joint boundary technique is used to obtain the error probability boundary , ,in and are the transmitting sequence and the receiving sequence respectively, is a uniformly randomly distributed variable, is the generalized information density. For the length of each message, use get in ,when hour, , is a free parameter, .

[0091] Further, let , combined with the probability density function , and then use the Gaussian approximation principle to get , , so we get the error probability bound The calculation formula is: ,in for function, , and Calculated by the following formula:

[0092] .

[0093] Finally, when other parameters are fixed, we only discuss the transmission block length. The impact on the error probability boundary can be calculated according to the above steps Curve, where the input parameter is the block length , the output parameter is the lower bound of the achievable error probability . The curve is the reliability model used in the present invention.

[0094] The method for establishing the delay performance model of the deterministic resource allocation method in step S3 can be divided into the following four steps:

[0095] (1) If Figure 3 As shown, the present invention sets each user Received in seconds The basic allocation unit of time is set as time slot , that is, each time slot can complete The transmission of symbols. Let the length of the scheduling period be Time slot, i.e. Therefore, after adopting deterministic resource allocation, the service time of each user in period T is time slot.

[0096] (2) If Figure 4 As shown, the delay probability analysis of the present invention in the queuing theory model is: the arrival interval of the message follows the mean of The negative exponential distribution of seconds, the average number of messages arriving in a time slot is , Arrived within time slot The probability of a message is The number of messages in the user buffer after each service opportunity is defined as a state variable ,make Indicates the slave state : To status : The steady-state transition probability of and is a non-negative integer:

[0097] ;

[0098] Steady-state transition probability is a state variable The state transition probability matrix The constituent elements of the state transition probability matrix Substitute into the formula , calculate the steady-state probability vector ; Steady-state probability vector The elements in the symbol express, Status : The steady-state probability of is a non-negative integer;

[0099] The number of delay slots experienced by any message is The delay probability is , using the above steady-state probability vector and message arrival probability Analyze the delay probability in three cases :

[0100] Case 1: hour, ;

[0101] Case 2: hour, ;in, , is any non-negative integer, , ;

[0102] Case 3: hour, ,in, , is any non-negative integer;

[0103] ;

[0104] (3) By , calculate the timeout probability exceeding the maximum delay D , is the channel coefficient, The delay performance model used in the present invention can be expressed as Curve, whose input parameter is the length of the scheduling interval , the output parameter is the timeout probability .

[0105] Furthermore, according to the above steps S1-S3, the integer optimization problem of constructing the URLLC resource allocation model based on the reliability and delay performance model in step S4 can be obtained. The specific method is as follows:

[0106] The deterministic resource allocation method of the present invention needs to consider the power of the system , service opportunities , bandwidth allocation The resource allocation subtask related to user scheduling includes parameters such as the association parameters between users and subchannels and the scheduling period. The optimization problem considered aims to minimize the required bandwidth and transmission. Therefore, the objective function can be expressed as minimizing the product of the required bandwidth and transmission power, as follows:

[0107] ;

[0108] There are 6 sets of constraints in the optimization problem: the first and second sets of constraints require the user to The reliability and delay performance meet the needs of URLLC communication; the third and fourth groups of constraints limit the user Transmission power and sub-channel The scheduling cycle length Only discrete sets and The values ​​in , and the sizes of the two sets are and ; The fifth set of constraints is user Number of time slots occupied by message transmission Set a cap ; The fifth set of constraints uses associated parameters Restricted users Can only communicate with one subchannel of association; is the total number of sub-channels; is the lower bound of the achievable error probability and the error probability bound; For users The error probability bound; is the tolerable timeout probability, For users The timeout probability, For users after adopting deterministic resource allocation In the cycle The number of time slots corresponding to the service duration within.

[0109] In step S5, a heuristic algorithm is designed based on the optimization problem to obtain a setting scheme for resource parameters such as system transmission power, block length, user scheduling, and bandwidth and time allocation, ultimately minimizing the system bandwidth and transmission power. The specific implementation process of the algorithm is divided into the following steps:

[0110] (1) For users and possible transmission power sets , according to the reliability performance model based on finite block length established in step S2 , obtain the transmission block length set that meets the reliability requirements, and further convert the transmission block length set into a time slot vector .

[0111] (2) For each user and time slot vector , according to the delay model of the deterministic resource allocation method established in step S3 , obtain the scheduling cycle length vector that meets the delay performance requirements .

[0112] (3) For each user and scheduling cycle vector ,by The mean of is used as the metric, and the labels of K users are stored in the set in ascending order of the metric value. .

[0113] (4) The first user in Add subchannel l, subchannel l scheduling period at different power ,user The transmission power set , time slot vector And the corresponding scheduling cycle Composing a set of resource allocation plans .

[0114] (5) Continue adding sets for subchannel l Next user in , and set the transmission power to , time slot vector Add to resource allocation plan set The scheduling period of subchannel l Each element is updated to its original With users Scheduling cycle The minimum value of the corresponding element is repeated until the time slot resources in one scheduling cycle of subchannel l are exhausted.

[0115] (6) Using power consumption as a metric, select the resource allocation scheme with the minimum metric for subchannel l. Change to another subchannel and repeat steps (4) to (6) until the set All users can be allocated resources.

[0116] Through the above method, the present invention can effectively complete resource allocation and ensure the communication reliability and delay performance of the URLLC system. Figure 5 and 6 What is shown is the reliability and delay performance curve of the above method used in the present invention. Figure 5 is a diagram of the cumulative distribution function of the transmission error probability. Figure 6 It is a diagram of the cumulative distribution function of the delay timeout probability.

[0117] Through the above method, the present invention can effectively complete resource allocation and save the bandwidth of the URLLC system. Figure 7-9 The figure shows the influence of the number of users on the number of sub-channel consumption by using the above method in the present invention. Figure 7 Schematic diagram comparing sub-channel consumption with changing number of users of this method and the control method, wherein the "minpower" method is the control group. The only difference between its resource allocation implementation process and the method described in the present invention is that the minimum transmission power of the user is limited to save power. Figure 7 This shows that the method of the present invention has an advantage in saving channel resources compared with the control group method. Figure 8 and 9 The changing trends of different performance requirements of the above method used in the present invention are shown. Figure 8 Schematic diagram of sub-channel consumption for changing the number of users and delay performance requirements. Figure 9 Schematic diagram of sub-channel consumption for varying number of users and reliability performance requirements.

[0118] Example 2

[0119] Based on the same inventive concept as that of Example 1, an embodiment of the present invention provides a resource allocation device applicable to a URLLC system, including:

[0120] A reliability performance model generation module, configured to generate a reliability performance model based on a finite block length based on transmission parameters and resource allocation parameters;

[0121] A delay performance model generation module, configured to generate a delay performance model of a deterministic resource allocation method based on transmission parameters and resource allocation parameters;

[0122] A URLLC resource allocation model construction module is used to construct a URLLC resource allocation model with the goal of minimizing bandwidth and transmission power;

[0123] The resource allocation module is used to solve the URLLC resource allocation model by combining the reliability performance model and the delay performance model to obtain a resource allocation solution.

[0124] The rest are the same as in Example 1.

[0125] Example 3

[0126] Based on the same inventive concept as Example 1, a resource allocation system applicable to a URLLC system in an embodiment of the present invention includes a storage medium and a processor;

[0127] The storage medium is used to store instructions;

[0128] The processor is configured to operate according to the instructions to perform the method according to any one of the embodiments 1.

[0129] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0130] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0131] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0132] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0133] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which are all protected by the present invention.

[0134] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A resource allocation method applicable to a URLLC system, characterized in that: include: Based on the transmission parameters and resource allocation parameters, a reliability performance model based on finite block length is generated; generating a delay performance model of a deterministic resource allocation method based on transmission parameters and resource allocation parameters; A URLLC resource allocation model is constructed with the goal of minimizing bandwidth and transmission power. Combining the reliability performance model and the delay performance model, solving the URLLC resource allocation model to obtain a resource allocation solution; The method for generating the delay performance model includes: For different scheduling interval lengths S, the corresponding timeout probability δ(S) is calculated based on the timeout probability calculation formula; curve fitting is performed based on the different scheduling interval lengths S and the corresponding timeout probability δ(S) to generate a delay performance model, where the input parameter of the delay performance model is the scheduling interval length and the output parameter is the timeout probability; The calculation formula of the timeout probability is obtained by the following method: Set the time each user can receive data every T seconds to nT sym service opportunities, n is the transmission block length after user coding modulation, T sym is the symbol transmission rate of the physical layer; the basic allocation unit of time is set as time slot T slot , T slot =N sym T sym , indicating that each time slot can complete N sym Transmission of symbols; Let the length of the scheduling cycle be S time slots, T = ST slot , after adopting deterministic resource allocation, the service time of each user in period T is W, The arrival interval of messages follows a negative exponential distribution with a mean of μ seconds, and the average number of messages arriving in a time slot is λ = T slot / μ, the message arrival probability of β messages arriving within N time slots is θ N,β , The number of messages in the user buffer after each service opportunity is defined as the state variable z, represents the steady-state transition probability from state i1: z = i1 to state i2: z = i2, where i1 and i2 are non-negative integers; Steady-state transition probability is the component element of the state transition probability matrix P of the state variable z; substitute the state transition probability matrix P into the formula πP=π to calculate the steady-state probability vector π; the elements in the steady-state probability vector π are represented by the symbol π i Indicates that π i is the steady-state probability of state i: z = i, i is a non-negative integer; The probability that any message experiences a delay of d time slots is p d , using the above steady-state probability vector π and message arrival probability θ N,β Analyze the delay probability p in three cases d : Case 1: When 0≤d≤W-1, p d =0; Case 2: When d=rS+W+τ, Where, 0≤τ≤SW-1, r is any non-negative integer, u=r-i+1-β, Case 3: When d=rS+S+τ, in: Where, 0≤τ≤W-1, r is any non-negative integer, h is the channel coefficient, h~CN(0,γ), γ is the variance of the channel coefficient, which is a variable parameter; Depend on Calculate the timeout probability δ exceeding the maximum delay D; The objective function of the URLLC resource allocation model is: my L∑ k P k The constraints of the URLLC resource allocation model are: st k =e d k =d Among them, the first and second group constraints require that the reliability and delay performance of user k meet the needs of URLLC communication; the third and fourth group constraints limit the transmission power P of user k. k and the scheduling period length S of subchannel l l Only from the discrete set Ω P and Ω S The values ​​in the two sets are imax and qmax respectively; the fifth set of constraints is the number of time slots W occupied by user k’s message transmission k Set an upper limit W max ; The sixth set of constraints uses the associated parameter x k,l User k is restricted to being associated with only one subchannel l; L is the total number of subchannels; ε is the lower bound of the achievable error probability; ε k is the error probability boundary of user k; δ is the tolerable timeout probability, δ k is the timeout probability of user k, W k is the number of time slots corresponding to the service duration of user k in period T after adopting deterministic resource allocation.

2. A resource allocation method applicable to a URLLC system according to claim 1, characterized in that: The method for generating the reliability performance model includes: For different user transmission block lengths n, the corresponding error probability boundary value ε(n) is calculated based on the calculation formula of the error probability boundary; Curve fitting is performed based on the transmission block length n of different users and the corresponding error probability boundary value ε(n) to generate a reliability performance model, where the input parameter of the reliability performance model is the transmission block length and the output parameter is the error probability boundary value.

3. A resource allocation method applicable to a URLLC system according to claim 2, characterized in that: The calculation formula of the error probability boundary is obtained by the following method: In a flat Rayleigh fading channel, the non-coherent reception technique is used to model the channel as Among them, x is the transmission symbol, and the transmission symbol x is from multiple amplitude modulation constellations {α1,α2,...,α M } are uniformly selected, and α m ≥0, 1≤m≤M, M is the amplitude modulation order, which is a positive integer greater than 0; y is the received symbol; P is the normalized transmission power, which is equal to the ratio of the actual transmission power to the actual noise power; w is the power-normalized noise, w~CN(0,1), CN(0,1) represents a complex Gaussian distribution with mean 0 and variance 1; h is the channel coefficient, h~CN(0,γ), γ is the variance of the channel coefficient, which is a variable parameter; Normalize the constellation's average power And calculate the average signal-to-noise ratio of transmission ρ, ρ = Pγ, and then calculate the probability density function f of the non-coherent received symbol m (y), in, Using random coding joint boundary technology, we can obtain the error probability boundary ε, Where x=[x1,x2,...,x n ] and y=[y1,y2,...,y n ] are the transmitting sequence and receiving sequence respectively, U is a uniform random distribution variable, i s (·,·) is the generalized information density, b is the length of each message, and f m (y) gets in When x j =α m When λ j =λ m , s is a free parameter, s≥0; make Combined with the probability density function f m (y), using Gaussian approximation principle to get Z s , Then we get the calculation formula of the error probability boundary ε, which is: Where Q(·) is the Q function, η s =nC s -1-ln(2 b -1), 4. The resource allocation method applicable to a URLLC system according to claim 1, wherein: Solving the URLLC resource allocation model by combining the reliability performance model and the delay performance model to obtain a resource allocation solution includes: For each user k and possible transmission power set P k , transmission power set P k There are imax power elements in , according to the reliability performance model ε(n), a transmission block length set that meets the reliability requirements is obtained, and a time slot vector W is generated based on the transmission block length set k,imax , time slot vector W k,imax There are imax time slot elements in ; For each user k and time slot vector W k,imax , according to the delay model δ(S), obtain the scheduling cycle length vector S that meets the delay performance requirements k,imax , scheduling cycle length vector S k,imax There are imax scheduling cycle length elements in ; For each user k and scheduling period vector S k,imax , to schedule the period vector S k,imax The mean of is used as the metric, and the labels of the K users are stored in the set Λ in ascending order of the metric value; For each subchannel, repeat the following steps until all users in the set Λ are allocated resources: Add the first user k in the set Λ to the subchannel l and define the scheduling period of the subchannel l at different powers. For S k,imax , the power set P of user k k , time slot vector W k,imax And the corresponding scheduling cycle Composition of resource allocation plan set C l ; Continue to add the next user k' in the set Λ to subchannel l, and set the power set P of user k' to k' , time slot vector W k',imax Add to resource allocation plan set C l , the scheduling period of subchannel l Each element is updated to its original With user k' scheduling period S k',imax The minimum value in the corresponding element is repeated until the time slot resources in one scheduling cycle of subchannel l are exhausted; Taking power consumption as the metric, select the resource allocation scheme with the minimum metric for subchannel l.

5. The resource allocation method applicable to a URLLC system according to claim 1, characterized in that: The resource allocation scheme includes transmission power, transmission block length, bandwidth, association parameters between users and sub-channels, scheduling period and service duration of users in each period.

6. A resource allocation device suitable for a URLLC system, characterized in that: include: A reliability performance model generation module, configured to generate a reliability performance model based on a finite block length based on transmission parameters and resource allocation parameters; A delay performance model generation module, configured to generate a delay performance model of a deterministic resource allocation method based on transmission parameters and resource allocation parameters; A URLLC resource allocation model construction module is used to construct a URLLC resource allocation model with the goal of minimizing bandwidth and transmission power; A resource allocation module, configured to solve the URLLC resource allocation model by combining the reliability performance model and the delay performance model to obtain a resource allocation solution; The method for generating the delay performance model includes: For different scheduling interval lengths S, the corresponding timeout probability δ(S) is calculated based on the timeout probability calculation formula; curve fitting is performed based on the different scheduling interval lengths S and the corresponding timeout probability δ(S) to generate a delay performance model, where the input parameter of the delay performance model is the scheduling interval length and the output parameter is the timeout probability; The calculation formula of the timeout probability is obtained by the following method: Set the time each user can receive data every T seconds to nT sym service opportunities, n is the transmission block length after user coding modulation, T sym is the symbol transmission rate of the physical layer; the basic allocation unit of time is set as time slot T slot , T slot =N sym T sym , indicating that each time slot can complete N sym Transmission of symbols; Let the length of the scheduling cycle be S time slots, T = ST slot , after adopting deterministic resource allocation, the service time of each user in period T is W, The arrival interval of messages follows a negative exponential distribution with a mean of μ seconds, and the average number of messages arriving in a time slot is λ = T slot / μ, the message arrival probability of β messages arriving within N time slots is θ N,β , The number of messages in the user buffer after each service opportunity is defined as the state variable z, represents the steady-state transition probability from state i1: z = i1 to state i2: z = i2, where i1 and i2 are non-negative integers; Steady-state transition probability is the component element of the state transition probability matrix P of the state variable z; substitute the state transition probability matrix P into the formula πP=π to calculate the steady-state probability vector π; the elements in the steady-state probability vector π are represented by the symbol π i Indicates that π i is the steady-state probability of state i: z = i, i is a non-negative integer; The probability that any message experiences a delay of d time slots is p d , using the above steady-state probability vector π and message arrival probability θ N,β Analyze the delay probability p in three cases d : Case 1: When 0≤d≤W-1, p d =0; Case 2: When d=rS+W+τ, Where, 0≤τ≤SW-1, r is any non-negative integer, u=r-i+1-β, Case 3: When d=rS+S+τ, in: Where, 0≤τ≤W-1, r is any non-negative integer, h is the channel coefficient, h~CN(0,γ), γ is the variance of the channel coefficient, which is a variable parameter; Depend on Calculate the timeout probability δ exceeding the maximum delay D; The objective function of the URLLC resource allocation model is: my L∑ k P k The constraints of the URLLC resource allocation model are: st k =e d k =d Among them, the first and second group constraints require that the reliability and delay performance of user k meet the needs of URLLC communication; the third and fourth group constraints limit the transmission power P of user k. k and the scheduling period length S of subchannel l l Only from the discrete set Ω P and Ω S The values ​​in the two sets are imax and qmax respectively; the fifth set of constraints is the number of time slots W occupied by user k’s message transmission k Set an upper limit W max ; The sixth set of constraints uses the associated parameter x k,l User k is restricted to being associated with only one subchannel l; L is the total number of subchannels; ε is the lower bound of the achievable error probability; ε k is the error probability boundary of user k; δ is the tolerable timeout probability, δ k is the timeout probability of user k, W k is the number of time slots corresponding to the service duration of user k in period T after adopting deterministic resource allocation.

7. A resource allocation system suitable for a URLLC system, characterized in that: including storage media and processors; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the method according to any one of claims 1-5.

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