CN108834175B - Queue-driven equipment access and resource allocation joint control method in mMTC network - Google Patents

Abstract

The invention discloses a queue-driven device access and resource allocation joint control method in a mMTC network, comprising: 1) a base station broadcasts an access control parameter p and configuration information of a physical random access channel PRACH; 2) a backlog in the mMTC network Each device in the device generates a random number, and when the random number is less than the control parameter p, the access control program is successfully passed; 3) each activated device in step 2) transmits the selected pilot frequency and the respective device ID information; 4) when When the pilot frequency is only selected by one device, the base station can successfully decode the corresponding device ID information; otherwise, the base station cannot successfully decode the corresponding device ID information; 5) When the activation device is randomly accessed, and the activation device The allocated PUSCH channel is idle, and data transmission is initiated immediately; 6) The base station broadcasts the corresponding idle indication at the end of the current time slot; 7) Repeat steps 2) to 6) until all data transmissions are completed, this method can effectively improve throughput of the network.

Description

A Queue-driven device access and resource allocation joint control method in mMTC network

technical field

The invention belongs to the technical field of wireless communication, and relates to a queue-driven device access and resource allocation joint control method in a mMTC network.

Background technique

With the rapid development of the Internet of Things (IoT) for the Internet of Everything and ubiquitous information acquisition and exchange, massive Machine-Type communication (mMTC) has been proposed as one of the three major scenarios in the future 5G network. An important class of communication scenarios. At present, machine type (MTC) devices in daily life have been widely used, such as: monitoring devices in intelligent traffic management systems, wearable devices in smart medical care, automatic control devices for Industry 4.0, fire or emergency warning systems Sensing equipment in , etc. It is estimated that in the next 10 years, there will be more than 50 billion MTC devices in the wireless network, and the mMTC network has a huge application prospect.

However, when faced with the simultaneous access and transmission of a huge number of devices in the mMTC network, there are still two key technical challenges: the first challenge is how to carry out effective congestion control, when a large number of devices initiate access at the same time If there is no corresponding access control procedure, the network will have severe pilot collisions due to limited pilot resources, resulting in network congestion. Numerous researchers have proposed their own technical solutions to alleviate network congestion. Another challenge is how to efficiently allocate resources between the Physical Random Access Channel (PRACH) and the Physical Uplink Shared Channel (PUSCH) under the premise of a certain total radio resources. This is a problem that many researchers tend to ignore. They often assume that there are enough PUSCH resources in the network for subsequent data transmissions by successfully accessing devices. In fact, under the condition of limited total resources, even if the device successfully accesses in the competition access phase, the device will fail to transmit due to lack of corresponding PUSCH resources; on the other hand, if too many resources are divided into PUSCH, In the competition access stage, serious pilot frequency collisions will occur, resulting in a sharp drop in the number of successful accesses, which also results in a waste of resources. Therefore, there is a balance in the allocation between PRACH and PUSCH resources, and how to obtain the best balance is a problem worthy of study.

In order to meet the above challenges, a random contention access and data transmission process for mMTC needs to be improved and designed, and a corresponding queue-driven device access and resource allocation joint control scheme is proposed to improve the network throughput.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the above shortcomings of the prior art, and to provide a queue-driven device access and resource allocation joint control method in an mMTC network, which can effectively improve the network throughput.

In order to achieve the above object, the method for joint control of device access and resource allocation driven by a queue in the mMTC network of the present invention comprises the following steps:

1) When the time slot starts, the base station broadcasts the access control parameter p of the current time slot and the configuration information of the physical random access channel PRACH to all devices in the mMTC network through the downlink channel;

2) Each backlogged device in the mMTC network generates a random number evenly in the interval (0, 1). When the random number generated by any device is less than the control parameter p, the device successfully passes the access control program and will successfully pass The device that accesses the control program is recorded as the active device; when the random number generated by any device is greater than or equal to the control parameter p, the device is blocked in the current time slot, and the device retreats to the next time slot and tries to pass the access again. control program;

3) each activation device in step 2) selects the pilot frequency from the pilot frequency pool, and then transmits the selected pilot frequency and the respective equipment ID information to the base station on the PRACH;

4) After receiving the selected pilot frequency, the base station attempts to decode the corresponding device ID information. When the pilot frequency is only selected by one device, the base station can successfully decode the corresponding device ID information, and the pilot frequency is successfully transmitted at this time; when When the pilot frequency is selected by multiple devices, the base station cannot successfully decode the corresponding device ID information; the base station will detect the successfully transmitted pilot frequency as a random access response RAR;

5) When the activation device in the mMTC network receives the random access response RAR that matches its own pilot frequency and device ID information, it indicates that the activation device has a successful random access. If the channel idle flag in the RAR is true, it indicates that the The allocated PUSCH channel is idle, and the activating device immediately initiates data transmission on the PUSCH channel. If the channel idle flag in the RAR is false, the activating device enters the waiting state until it receives the channel idle indicator broadcast by the base station in the subsequent timeslot. When the activation device does not receive a random access response RAR that matches its own pilot frequency and device ID information, it indicates that the activation device fails to access, and then it needs to retry to pass the access control procedure in the next time slot;

6) The base station judges whether the occupied PUSCH channel resources re-enter idle according to the mark at the end of the transmission data of each active device, and counts the re-entered idle channels in the current time slot, and then broadcasts the corresponding idle indication at the end of the current time slot, When the device in the waiting state receives the idle indication of its own channel, it starts to transmit data in the next time slot;

7) Repeat steps 2) to 6) until all data transmissions are completed, and complete the joint control of queue-driven device access and resource allocation in the mMTC network.

In step 4), the random access response RAR includes the identified pilot frequency, device ID information, pre-allocated RUSCH information and channel idle flag.

The configuration information of the physical random access channel PRACH in step 1) is the resource block RBs used for pilot transmission in the random access phase and its number d ^* , correspondingly, the number of PUSCH resource blocks used for data transmission l=qd ^* , where q is the total number of resource blocks in the mMTC network. Assuming that m resource blocks and n resource blocks are required to construct a pilot and PUSCH channel, the number of pilots M and the number of PUSCH channels T in the mMTC network are:

及最优的激活设备数均值r^*确定，其中，The access control parameter p is the size of the window that controls the load in the access control program, and the access control parameter p is the estimated value of the average number of backlogged devices in the current time slot.

and the optimal average number of active devices r ^* is determined, where,

Among them, the solution process of (r ^* , d ^* ) is:

Let F be the number of devices with new services arriving in the current time slot, B is the number of blocked devices in step 2), C is the number of devices that have pilot collisions in step 4), and A is the number of backlogged devices, then A = F+B+C; Assuming that the new business arrives through a Poisson process with an intensity of λ, the number of backlogged equipment A can be approximated by a Poisson distribution with a mean value of a. Correspondingly, the number of activated equipment R obeys the mean value of r=pa Poisson distribution, suppose the number of devices that select pilot b at the same time is M _b , then M _b obeys Poisson distribution with mean r/M, and random variables M _b , b=1, ..., M are independent of each other, so The number of successfully connected devices S obeys the binomial distribution with the parameter (M, P ₁₁ ):

where P ₁₁ is the probability that pilot b is selected by only one device:

Let the speed of the device waiting for the queue to arrive in step 5) be the number of devices S that are successfully accessed in each time slot, and the speed of the device waiting for the queue to leave the process is the maximum number of devices that can complete data transmission per time slot supported by the system T. , the length of the waiting queue is Q, then the relationship between the length Q t of the current time slot waiting queue and the length Q _{t +1} of the next time slot waiting queue is:

Q _t+1 =max{Q _t +ST,0}

In order to prevent the queue waiting time from being too long, the violation probability constraint for constructing the waiting queue length is:

Pr{Q> _Qth }<e

In order for the waiting queue length to violate the probability constraint, it is necessary to ensure that:

Ψ(S, θ)≤Φ(T, θ)

Among them, Ψ(S, θ) and Φ(T, θ) represent the effective access rate and effective transmission rate of the queuing system, respectively, where,

where θ is the target queue index, where,

According to the queuing theory, when the waiting queue is stable, the average departure rate of the waiting queue is equal to the average arrival rate. Let the average rate be the system throughput ζ, there are:

Construct an optimization problem with resource allocation d ^* and activation device strength r ^* as independent variables, and the optimization objective of maximizing system throughput, namely

s.t.Ψ(S, θ)≤Φ(T, θ)

The optimization problem is solved to obtain the optimal resource allocation d ^* and activation equipment strength r ^* .

A two-step search algorithm is used to solve the optimization problem, and the optimal resource allocation d ^* and activation equipment strength r ^* are obtained.

The base station adopts an iterative algorithm to decide the access control parameter ρ and the configuration information of the physical random access channel PRACH in each time slot.

The present invention has the following beneficial effects:

In the specific operation, the queue-driven device access and resource allocation joint control method in the mMTC network of the present invention adds a queuing and waiting process between the random access and data transmission stages, and dynamically adjusts the devices successfully accessed in the network. The relationship between the number of devices and the number of devices successfully transmitted can avoid the waste of access resources or transmission resources to improve the throughput of the system.

Further, the present invention improves the throughput of the system and the robustness of the network by jointly optimizing the access control parameters and resource allocation.

Further, by adjusting the waiting queue index to adapt to the length of the waiting queue with different strengths, the probability constraint is violated, so as to adapt to different service delay requirements.

Description of drawings

Fig. 1 is the mMTC network scene diagram in the present invention;

Fig. 2 is the improved random access and data transmission flow chart in the present invention;

Fig. 3 is the principle block diagram of joint access control and resource allocation strategy in the present invention;

Fig. 4 is the change curve diagram of the system capacity with the queue index realized in the present invention;

FIG. 5 is a performance comparison diagram of the system capacity of the present invention and the prior art solution changing with the queue index;

FIG. 6 is a performance comparison diagram of the system throughput of the present invention and the prior art solution with the change of the arrival intensity of the new service;

FIG. 7 is a performance comparison diagram of the successful access probability of the present invention and the prior art solution as a function of the arrival intensity of new services;

8 is a performance comparison diagram of the average value of the number of backlogged equipments of the present invention and the prior art solution as a function of the arrival intensity of new services;

FIG. 9 is a performance comparison diagram of the team leader violation probability with the threshold value of the solution of the present invention and the prior art.

Detailed ways

Below in conjunction with accompanying drawing, the present invention is described in further detail:

Referring to FIG. 1 and FIG. 2 , in the large-scale communication network, a large number of MTC devices randomly access the base station in a contention-based manner, and transmit their respective data, wherein, new services in the network arrive in a Poisson process with an intensity of λ. , assuming that the data volume of each service is the same, the base station divides the q resource blocks in the network into PRACH resources for random access, PUSCH resources for data transmission and sets the optimal access control parameter p to relieve network congestion.

The method for joint control of device access and resource allocation driven by queues in the mMTC network of the present invention comprises the following steps:

1) When the time slot starts, the base station broadcasts the access control parameter p of the current time slot and the configuration information of the physical random access channel PRACH to all devices in the mMTC network through the downlink channel;

2) Each backlogged device in the mMTC network generates a random number evenly in the interval (0, 1). When the random number generated by any device is less than the control parameter p, the device successfully passes the access control program and will successfully pass The device that accesses the control program is recorded as the active device; when the random number generated by any device is greater than or equal to the control parameter p, the device is blocked in the current time slot, and the device retreats to the next time slot and tries to pass the access again. control program;

3) each activation device in step 2) selects the pilot frequency from the pilot frequency pool, and then transmits the selected pilot frequency and the respective equipment ID information to the base station on the PRACH;

4) After receiving the selected pilot frequency, the base station attempts to decode the corresponding device ID information. When the pilot frequency is only selected by one device, the base station can successfully decode the corresponding device ID information, and the pilot frequency is successfully transmitted at this time; when When the pilot frequency is selected by multiple devices, the base station cannot successfully decode the corresponding device ID information; the base station will detect the successfully transmitted pilot frequency as a random access response RAR;

5) When the activation device in the mMTC network receives the random access response RAR that matches its own pilot frequency and device ID information, it indicates that the activation device has a successful random access. If the channel idle flag in the RAR is true, it indicates that the The allocated PUSCH channel is idle, and the activating device immediately initiates data transmission on the PUSCH channel. If the channel idle flag in the RAR is false, the activating device enters the waiting state until it receives the channel idle indicator broadcast by the base station in the subsequent timeslot. When the activation device does not receive a random access response RAR that matches its own pilot frequency and device ID information, it indicates that the activation device fails to access, and then it needs to retry to pass the access control procedure in the next time slot;

6) The base station judges whether the occupied PUSCH channel resources re-enter idle according to the mark at the end of the transmission data of each active device, and counts the re-entered idle channels in the current time slot, and then broadcasts the corresponding idle indication at the end of the current time slot, When the device in the waiting state receives the idle indication of its own channel, it starts to transmit data in the next time slot;

7) Repeat steps 2) to 6) until all data transmissions are completed, and complete the joint control of queue-driven device access and resource allocation in the mMTC network.

In step 4), the random access response RAR includes the identified pilot frequency, device ID information, pre-allocated RUSCH information and channel idle flag.

The configuration information of the physical random access channel PRACH in step 1) is the resource block RBs used for pilot transmission in the random access phase and its number d ^* , correspondingly, the number of PUSCH resource blocks used for data transmission l=qd ^* , where q is the total number of resource blocks in the mMTC network. Assuming that m resource blocks and n resource blocks are required to construct a pilot and PUSCH channel, the number of pilots M and the number of PUSCH channels T in the mMTC network are:

及最优的激活设备数均值r^*确定，其中，The access control parameter p is the size of the window that controls the load in the access control program, and the access control parameter p is the estimated value of the average number of backlogged devices in the current time slot.

and the optimal average number of active devices r ^* is determined, where,

Among them, the solution process of (r ^* , d ^* ) is:

Let F be the number of devices with new services arriving in the current time slot, B is the number of blocked devices in step 2), C is the number of devices that have pilot collisions in step 4), and A is the number of backlogged devices, then A = F+B+C; Assuming that the new business arrives through a Poisson process with an intensity of λ, the number of backlogged equipment A can be approximated by a Poisson distribution with a mean value of a. Correspondingly, the number of activated equipment R obeys the mean value of r=pa Poisson distribution, suppose the number of devices that select pilot b at the same time is M _b , then M _b obeys Poisson distribution with mean r/M, and random variables M _b , b=1, ..., M are independent of each other, so The number of successfully connected devices S obeys the binomial distribution with the parameter (M, P ₁₁ ):

where P ₁₁ is the probability that pilot b is selected by only one device:

Let the speed of the device waiting for the queue to arrive in step 5) be the number of devices S that are successfully accessed in each time slot, and the speed of the device waiting for the queue to leave the process is the maximum number of devices that can complete data transmission per time slot supported by the system T. , the length of the waiting queue is Q, then the relationship between the length Q t of the current time slot waiting queue and the length Q _{t +1} of the next time slot waiting queue is:

Q _t+1 =max{Q _t +ST,0}

In order to prevent the queue waiting time from being too long, the violation probability constraint for constructing the waiting queue length is:

Pr{Q> _Qth }<e

In order for the waiting queue length to violate the probability constraint, it is necessary to ensure that:

Ψ(S, θ)≤Φ(T, θ)

Among them, Ψ(S, θ) and Φ(T, θ) represent the effective access rate and effective transmission rate of the queuing system, respectively, where,

where θ is the target queue index, where,

According to the queuing theory, when the waiting queue is stable, the average departure rate of the waiting queue is equal to the average arrival rate. Let the average rate be the system throughput ζ, there are:

Construct an optimization problem with resource allocation d ^* and activation device strength r ^* as independent variables, and the optimization objective of maximizing system throughput, namely

s.t.Ψ(5, θ)≤Φ(T, θ)

The optimization problem is solved to obtain the optimal resource allocation d ^* and activation equipment strength r ^* .

A two-step search algorithm is used to solve the optimization problem, and the optimal resource allocation d ^* and activation equipment strength r ^* are obtained, specifically:

有效接入速率的峰值Ψ(S，θ)|_r＝M及有效传输速率Φ(T，θ)|_r＝M；1a) Initialize d ^* =d=1 and ζ ^* =0, calculate the corresponding

The peak value of the effective access rate Ψ(S, θ)| _r=M and the effective transmission rate Φ(T, θ)| _r=M ;

Case 1: Ψ(S, θ)| _r=M <Φ(T, θ)| _r=M , then the optimal solution r ^* =M;

Case 2: Ψ(S, θ)| _r=M > Φ(T, θ)| _r=M , then the binary search equation Ψ(S, θ)=Φ(T is used on the real number interval [0, M] , the solution r ^* of θ);

1b) Calculate the corresponding throughput ζ=r ^* e- ^r/M , if ζ≥ζ ^* , update ζ ^* =ζ, d ^* =d, otherwise, do not update; let d=d+1, and go to Step 1a), until the search for solutions d ^* ∈ {1, 2, . . . , q-1} in the feasible solution set is completed.

The base station uses an iterative algorithm in each time slot to decide the access control parameter p and the configuration information of the physical random access channel PRACH, specifically:

2a) Network initialization: time slot p=1, the mean number of backlogged devices

则当前时隙的接入控制参数设置为：

PRACH资源分配数量为：d＝d^*；否则，接入控制参数设置为p＝1，并通过单步遍历搜索最优的PRACH资源分配数量：2b) If

Then the access control parameters of the current time slot are set as:

The PRACH resource allocation quantity is: d=d ^* ; otherwise, the access control parameter is set to p=1, and the optimal PRACH resource allocation quantity is searched by single-step traversal:

3c) broadcast the decision result (p, d) obtained in step 2b) to all MTC devices in the network;

3d) After the random access phase ends, count the number of collision pilots V _t in the current time slot, and estimate the mean value of the number of backlogged devices in the next time slot:

3e) Let t=t+1, enter the next time slot, repeat steps 2a) to 3d) until all data is completed.

Referring to FIG. 4, the system capacity refers to the maximum value of the system throughput achieved at the optimal solution (r ^* , d ^* ), it can be seen that the theoretical value of the present invention and the actual simulation value are perfectly matched, which confirms the theory of the present invention accuracy. In addition, the larger n is, the smaller the system capacity is, which is consistent with the intuition: the more wireless resources are required for each data transmission of a device, the weaker the system's processing capability.

A comparison scheme is selected, and the comparison scheme includes no queue scheme, no queue and no access control scheme, a queue but no team leader violation probability constraint scheme, and a traditional fixed resource allocation scheme (M=T).

It can be confirmed from the results in Figure 5 that when the queue index tends to 0, the present invention is close to the limit performance of the unconstrained scheme; when the queue index tends to +∞, the present invention tends to the traditional M=T scheme. For any captaincy threshold, the corresponding captain violation probability is 0, that is, the queue is always in an empty state, while the traditional M=T scheme can ensure that the number of devices successfully accessed per time slot is less than or equal to the maximum number of devices that can successfully transmit number, that is, to ensure that the queue length is 0, which corresponds to the performance of the present invention when the queue index tends to +∞. In addition, when θ≤0.2, the system capacity realized by the present invention is larger than the actual value of the non-queue scheme, and when θ=0.2, the team leader violates the probability constraint is relatively strict (for example, if the threshold Q _th =20, the corresponding violation probability ∈ = 0.0183 is already small). Therefore, the present invention can realize the system capacity second only to the limit performance scheme on the basis of an acceptable violation probability, confirming the superiority of the present invention over the conventional achievable scheme.

Referring to Fig. 6, Fig. 7 and Fig. 8, the present invention achieves greater system throughput when the intensity of the new service increases compared to the conventional achievable scheme (except for the extreme performance of the unconstrained scheme), and at all intensities Both achieve a higher probability of successful access and a lower backlog of devices in the system. In general, the maximum new service reaching intensity allowed by all schemes is constrained by the system capacity that can be achieved by their respective schemes. When the new service reaching intensity exceeds the capacity, the throughput achieved by the system converges to the capacity value and does not increase any more; And when the intensity of new service arrival is close to this capacity, the probability of successful access will drop rapidly, the number of backlogged devices increases exponentially and diverges to infinity with the increase of time slots, indicating that the system is on the verge of collapse. Based on the three indicators, the present invention achieves the performance that is second only to the unconstrained limit scheme. Compared with the traditional achievable scheme, when the system is stable, a higher probability of successful transmission and a lower number of backlogged devices can be achieved. Robust performance is also stronger.

Referring to Figure 9, the violation probability curve of the present invention is below the theoretical curve of the set constraints, indicating that the present invention fully meets the set captain violation probability requirements, while the other two comparison schemes lack corresponding requirements in the design, and the simulation results are serious. The captain violates the probability constraint.

Claims (6)

1. A queue-driven device access and resource allocation joint control method in an mMTC network is characterized by comprising the following steps:

1) when a time slot starts, a base station broadcasts an access control parameter p of the current time slot and configuration information of a Physical Random Access Channel (PRACH) to all equipment in an mMTC network through a downlink channel;

2) uniformly generating a random number by each accumulated device in the mMTC network in an interval (0, 1), and when the random number generated by any device is smaller than a control parameter p, successfully accessing the control program by the device, and marking the device successfully accessing the control program as an activated device; when the random number generated by any equipment is more than or equal to the control parameter p, the equipment is blocked in the current time slot, and the equipment backs off to the next time slot to try to pass through the access control program again;

3) each activation device in the step 2) selects a pilot frequency from the pilot frequency pool, and then transmits the selected pilot frequency and the ID information of each device to the base station on the PRACH;

4) the base station tries to decode the corresponding equipment ID information after receiving the selected pilot frequency, when the pilot frequency is selected by only one equipment, the base station can successfully decode the corresponding equipment ID information, and the pilot frequency is successfully transmitted; when the pilot frequency is selected by a plurality of devices, the base station cannot successfully decode the corresponding device ID information; the base station takes the pilot frequency which is successfully transmitted as a random access response RAR;

5) when an activation device in an mMTC network receives a Random Access Response (RAR) matched with self pilot frequency and device ID information, the activation device is indicated to be successfully accessed randomly, if the channel idle mark in the RAR is true, the assigned PUSCH is indicated to be idle, the activation device immediately initiates data transmission on the PUSCH, and if the channel idle mark in the RAR is false, the activation device enters a waiting state until a channel idle finger broadcasted by a base station in a subsequent time slot is received; when the activation equipment does not receive a random access response RAR matched with the self pilot frequency and equipment ID information, indicating that the activation equipment fails to access, and retrying to pass through an access control program in the next time slot;

6) the base station judges whether the occupied PUSCH channel resources re-enter the idle state or not according to the mark of the end of the data transmission of each activation device, counts to re-enter the idle channel in the current time slot, broadcasts a corresponding idle indication when the current time slot is finished, and starts to transmit data in the next time slot when the device in a waiting state receives the idle indication of the channel;

7) and repeating the steps 2) to 6) until all data transmission is finished, and finishing the joint control of equipment access and resource allocation driven by the queue in the mMTC network.

2. The method for joint control of queue-driven device access and resource allocation in an mtc network according to claim 1, wherein the random access response RAR comprises the identified pilot, device ID information, pre-allocated physical uplink shared channel PUSCH information, and channel idle flag.

3. The method for joint control of queue-driven device access and resource allocation in an mtc network according to claim 1, wherein the configuration information of the physical random access channel PRACH in step 1) is resource blocks RBs used for pilot transmission in the random access phase and the number d thereof^*Correspondingly, the number of PUSCH resource blocks for data transmission is l-q-d^*Wherein q is the total number of resource blocks in the mtc network, and if M resource blocks and n resource blocks are required to construct a pilot channel and a PUSCH channel, the number of pilot channels M and the number of PUSCH channels T in the mtc network are:

the access control parameter p is the window size for controlling the load in the access control program, and the access control parameter p is the estimated value of the average value of the backlog equipment number of the current time slot

And the optimal mean value r of the number of activated devices^*Determining, wherein,

4. the method for joint control of queue-driven device access and resource allocation in mMTC network of claim 3, wherein (r) is^*，d^*) The solving process of (2) is as follows:

setting F as the number of devices with new service arriving in the current time slot, B as the number of blocked devices in step 2), C as the number of devices with pilot collision in step 4), and A as the number of backlogged devices, then A is F + B + C; if a new service arrives in a poisson process with the strength of a, the backlog device number a may be approximated by a poisson distribution with the average value of a, correspondingly, the number R of activated devices follows the poisson distribution with the average value of R ═ pa, and the number of devices that simultaneously select the pilot b is set to M_bThen M is_bSubject to a Poisson distribution with a mean value r/M and a random variable M_bAnd b is 1, …, M are independent of each other, so the number S of successfully accessed devices obeys the parameter (M, P)₁₁) Two-term distribution:

wherein, P₁₁For the probability that pilot b is selected by only one device:

setting the rate in the process of arrival of the device waiting queue in the step 5) as the number S of devices successfully accessed in each time slot, the rate in the process of departure of the device waiting queue as the maximum number T of devices capable of completing data transmission in each time slot supported by the system, and the length of the waiting queue as Q, then the length Q of the waiting queue of the current time slot_tLength Q of waiting queue with next time slot_t+1The relationship of (1) is:

Q_t+1＝max{Q_i+S-T，0}

to prevent the queuing wait time from being too long, the violation probability constraint of the length of the waiting queue is constructed as follows:

Pr{Q＞Q_th}＜e

to make the wait queue length violation probability constraint hold, it is ensured that:

ψ(S，θ)≤Φ(T，θ)

where ψ (S, θ) and Φ (T, θ) denote an effective access rate and an effective transmission rate of the queuing system, respectively, where,

where θ is the target queue index, Q_thIs a threshold, wherein,

according to the queuing theory, when the waiting queue is stable, the average leaving rate of the waiting queue is equal to the average arriving rate, and the average rate is set as the throughput ζ of the system, then:

construction with resource Allocation d^*And activation device intensity r^*Optimization problems for the optimization objective of the independent variables to maximize the system throughput, i.e.

s.t.ψ(S，θ)≤Φ(T，θ)

Solving the optimization problem to obtain the optimal resource allocation d^*And activation device intensity r^*。

5. The method for joint control of queue-driven device access and resource allocation in an mtc network according to claim 1, wherein a two-step search algorithm is used to solve the optimization problem to obtain the optimal resource allocation d^*And activation device intensity r^*。

6. The method for joint control of equipment access and resource allocation driven by queues in an mMTC network according to claim 1, wherein a base station adopts an iterative algorithm to decide an access control parameter p and configuration information of a Physical Random Access Channel (PRACH) in each time slot.

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