WO2020119322A1 - Asynchronous wireless wake-up method and device - Google Patents

Abstract

The present application relates to an asynchronous wireless wake-up method, comprising: establishing a second-collision probability model of a channel, and estimating a packet loss probability α, a delay time TA, and total power consumption that are being monitored by a node in a wireless network; updating, by means of establishing a self-adaptive threshold selection mechanism, a threshold sequence of a terminal node; and upon successful data transmission or if an upper limit on the number of retransmissions has been reached, recording a current number of backoffs BN and a current backoff exponent BE, and when a matching address of a node wake-up receiver is erroneous, resetting a backoff timer and proceeding to the next backoff phase, and acquiring a current average transmission load and updating the second-collision probability model. The present application enables low-power wireless wake-up, reduces or prevents collisions caused by wake-up requests while also maintaining a wake-up success rate, and reduces interference to normal communication over the same channel.

Description

Asynchronous wireless wake-up method and equipment

This application requires the priority of the Chinese patent application submitted to the Chinese Patent Office on December 14, 2018, with the application number 201811533556.1 and the application name "an adaptive asynchronous wireless wake-up method based on the probability model of secondary collision", all of which are The content is incorporated into this application by reference.

Technical field

This application belongs to the technical field of wireless sensor network communication, and relates to an asynchronous wireless wake-up method.

Background technique

At present, with the rapid development of the Internet of Things, the low power consumption and long life cycle of network nodes have become critical issues that need to be solved urgently. Environmental monitoring in wild forests, unattended sensor network systems, and monitoring in industrial environments all require the use of large amounts of battery-powered equipment and instruments. A large number of technologies have studied the wireless wake-up low-power consumption technology. The main ones are: hardware circuit design technology, periodic wake-up technology, and energy absorption technology. The hardware circuit design is mainly through the design of a low-frequency low-power RF circuit, such as AS3933, as a separate module that only performs the wake-up task. When a wake-up request is found, it actively wakes up the microprocessor (microcontroller unit, MCU). On-demand wake-up technology, the node MCU has been in deep sleep for a long time until the receiving end of the wake-up transceiver receives a wake-up request to trigger an interrupt and switch it to a normal working state. Energy absorption technology mainly uses external vibration, light and other signals to gather energy to power the wake-up circuit and reduce battery energy consumption.

However, wireless wake-up transceivers (WuR) share antennas with the main transceiver through different modulation techniques, so collisions are likely to occur during the wake-up request and the success rate is low. Therefore, there is an urgent need to avoid collisions and wake up technology with a high success rate.

Summary of the invention

In view of this, this application provides an asynchronous wireless wake-up method for the application environment that requires wireless sensor network, using the number of terminal devices, the average arrival rate of data packets, and backoff, while meeting low power consumption and no additional circuit design overhead Window size, threshold of retransmission times, WuR sending rate and other information can identify whether the channel is currently busy or data collision occurs, and select the optimal backoff window size according to its packet loss rate, average delay, energy consumption, etc. Wireless wake-up reduces or avoids collisions caused by wake-up requests, improves the efficiency of successful wake-ups, and reduces interference with normal communication on the same channel.

To achieve the above purpose, this application provides the following technical solutions:

The first aspect of the present application provides an asynchronous wireless wake-up method, which is applied to a single-hop scenario of a wireless network node in a low-power environment data collection. The method may include the following steps: establishing a channel second collision probability model to estimate that the wireless network node has detected Packet loss rate α, delay time T _A and total average energy consumption E _A caused by busy channel and collision of wake-up requests. By establishing a threshold adaptive selection mechanism, the threshold sequence of the terminal node is updated. When the data transmission is successful or the upper limit of the number of retransmissions is reached , Record the current backoff times BN and backoff index BE. When the node wakes up the receiver to match the wrong address, reset the back-off timer and proceed to the next back-off phase. Calculate the current average transmission load size DS and other parameters to update the terminal nodes in the network.

Optionally, in combination with the first aspect above, in a first possible implementation manner, a secondary collision probability model of the channel is established to estimate the packet loss rate α and the delay time caused by the node in the wireless network monitoring the channel busy and the wakeup request collision T _A and total average energy consumption E _A , including: using the Markov chain M/G/1/2 queue model considering the exponential distribution of service time, introducing secondary collision and finite queue factors, and using C _T times short Clear channel assessment (CCA) evaluates the channel status, and can quickly back off when the channel is detected to be busy; again considering that the wake-up module based on subcarrier modulation and the main transceiver module share the same antenna to communicate on the same channel to increase The wake-up request transmission range, so the probability model of the second collision is obtained:

Among them, C _T is the initial value of the CCA channel detection timer, α is the probability of detecting a channel busy after the C _T channel detection is performed, N represents the number of nodes, including N-1 terminal nodes and 1 sink node, E[ Γ] is the total number of data packets sent by the node until the last data is sent. T _CCA is the time to perform a channel detection CCA, T _ta is the time to successfully send data to occupy the channel, and T _tc is the time to occupy the channel when the data is sent to collide , Λ is the average arrival rate of data packets, E[D _HoL ] is the average delay from the start of the node backoff window to sending data or reaching the upper limit of the number of retransmissions; D(k) is used to detect the busy channel during the k+1 backoff The number of channel detections, c(k) is the probability that the wake-up request is not successfully sent until the k+1th time, and d(k) is the probability that the wake-up request is not sent until the k+1th time but a collision occurs, expressed as:

c(k)=α ^k (1-β), d(k)=α ^k δ(1-α)

Where k is the current number of backoffs, M is the maximum number of retransmissions allowed by the node, β=α+δ(1-α) is the sum of channel busy probability and collision probability, and δ(1-α) is generated after the wake-up request is sent The probability of collision; c _sum is the _sum of the average probability of successfully sending data, and d _sum is the _sum of the average probability of collision when data is sent, which are expressed as:

The probability that more than two nodes simultaneously perform channel idle detection is expressed as:

δ＝1-P _SC ^N-2 ,

Among them, T _slot is the sum of the electromagnetic wave transmission delay, CCA detection time and the switching delay of the transceiver section, T _CCA is the time to perform a channel detection CCA, w _k is the back-off time and the average time spent on channel detection; δ is the detection of channel idle Probability, T _TA is the time required to send data, including the time occupied by the channel and the unoccupied time, expressed as: T _TA = T _wuc + T _on + T _h + T _l + T _SIFS + T _ACK , where T _wuc is the wake-up request transmission time, T _on is the time required for the MCU to switch from the sleep state to the normal working state, T _h is the time required for the data header transmission, T _l is the time required for the data field transmission, and T _SIFS is the frame interval, T _ACK is the time required to confirm the frame transmission;

The average delay of sending data after waking up is expressed as:

T _A =(1-β ^M+1 )T _S +α ^M+1 T _L +(β ^M+1 -α ^M+1 )T _C

Calculate the probability that each occurrence of the counter value is not 0 in M+1 times:

Where the probability of each collision accounts for the total probability

P _B = 1-P _C ,

It means that there are k+1-v times out of k+1 times that were not detected for the first time in the channel detection phase, but the channel was detected as busy before C _{T is} reduced to 0, and T _L is the time it takes to reach the upper limit of the number of retransmissions. Expressed as:

Among them, T _BO is the unit time consumed by back-off, W _k is the upper limit of back-off time during the k-th back-off; T _S is the back-off and channel detection time required to successfully send data, and T _C is the time consumed by collision when sending data, So T _S and T _C are expressed as:

Among them, T _TC is the time it takes to generate a secondary collision after sending data; similarly, the total average energy consumption E _{A of} backoff, channel detection and data transmission is expressed as:

E _A = (1-β ^M+1 )E _S +α ^M+1 E _L +(β ^M+1 -α ^M+1 )E _C

Among them, E _L is the energy consumed to discard the data packet when the upper limit of the number of retransmissions is reached, expressed as:

Among them, E _BO is the energy consumed for back-off, E _CCA is the energy consumed for performing a channel detection; E _S is the energy for back-off and channel detection required to successfully send data, and E _C is the energy consumed for collision when sending data, respectively for:

Among them, E _HoL is the energy consumed from the arrival of the data packet to the successful transmission, the energy consumed by the E _L backoff reaching the upper limit of the number of discarded data packets, E _TA is the energy consumed by the data during transmission, and E _TC is the data transmission The energy consumed when a collision occurs, P _LB is the probability and the probability of a second collision when the channel is busy and the channel detects idle when M+1 times of detection;

The comprehensive indicators of energy efficiency and packet loss rate are expressed as:

Among them, T _l is the time required to send the data load, E _factor is the energy efficiency weighting factor, P _LA is the probability of M+1 detection channels are busy; Finally, the terminal node will be based on the current state of the channel, delay, packet loss rate And record information to select the protocol and back-off window size to be used when the next wake-up request is sent.

Optionally, in combination with the above-mentioned first aspect, in a second possible implementation manner, updating the threshold sequence of the terminal node by establishing a threshold adaptive selection mechanism may include: performing node status when the number of wake-up request retransmissions increases Analysis; if the wake-up request collision probability increases, the back-off index BE is increased according to the efficiency curve; if the wake-up request collision probability decreases, the back-off index is reduced; and a threshold sequence TS is generated according to the adjusted back-off index. When the identifier is detected as 1, the back-off timer is reset, the next stage of back-off is performed, and the identifier is cleared.

Optionally, in combination with the first possible implementation manner of the first aspect above, in a third possible implementation manner, when the data transmission is successful or the upper limit of the number of retransmissions is reached, the current backoff times BN and backoff index BE are recorded; when the node When the wake-up receiver matches the wrong address, reset the back-off timer and proceed to the next back-off stage; and calculate the current average transmission load size DS to update the terminal nodes in the network, including: the terminal node first initializes the current back-off times BN to 1, Each backoff number BN increases by 1; the initial backoff index BE is CBE; the node first obtains the current backoff number BN. If it is less than the threshold TS(BN), the direct channel detection mode is used; if it is greater than the threshold TS(BN), the node Then backoff first, enter the channel detection state when the backoff timer is 0; the terminal node uses multiple short-term idle channel detections, each time the detection is completed, C _T decrements, and the value of C _T is 0 represents the end of the channel detection phase; if When one of them detects that the channel is busy, it is considered that there are other nodes currently communicating, and the next back-off process needs to be performed until the number of back-offs BN is greater than the maximum number of attempts; when all the tests show that the channel is idle, it means that the node can perform The operation to send a wake-up request.

Each time data is successfully transmitted or the upper limit of the number of retransmissions is reached, the current backoff times and backoff index are recorded, and the backoff times of the data sent in recent times are used to calculate W _BN through a weighting algorithm; and when the end node WuR has received other When the node's wake-up information, the identifier is set to 1, indicating that there are other nodes currently transmitting data to increase the back-off time; consider weighting the number of back-off times used in historical transmission of data, thus obtaining the formula:

W _BN = θ ₁ BN ₁ +θ ₂ BN ₂ +θ ₃ BN ₃ +θ ₄ BN ₄ +θ ₅ BN ₅

Among them, the smaller the subscript number indicates that the time is closer to the current time, θ indicates the weighting factor coefficient of each backoff times, and W _BN indicates the historical weighted backoff times.

Optionally, in combination with the first possible implementation manner of the first aspect described above, in a fourth possible implementation manner, when analyzing the cause of collision, adaptive modifications of different protocols are performed based on the channel secondary collision probability model.

Optionally, in combination with the second possible implementation manner of the first aspect above, in a fifth possible implementation manner, both the sink node and the terminal node use the wake-up transceiver WuR and the master transceiver MCU, and WuR and MCU respectively use Communicate on different frequencies.

A second aspect of the present application provides a device for asynchronous wireless wakeup, the device having a function of implementing the method of the first aspect or any possible implementation manner of the first aspect. This function can be realized by hardware, and can also be realized by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

A third aspect of the present application provides a computer-readable storage medium having instructions stored therein, which when run on a computer, enables the computer to execute the first aspect or any possible implementation manner of the first aspect Asynchronous wireless wake-up method.

A fourth aspect of the present application provides a computer program product containing instructions, which when run on a computer, enables the computer to execute the asynchronous wireless wakeup method of the first aspect or any possible implementation manner of the first aspect.

This application is aimed at the optimization of secondary collisions. It mainly adopts the method of software design, utilizes the low power consumption feature of wake-up radio frequency, and dynamically adjusts the back-off window and on-demand wake-up technology to realize wireless wake-up, reducing or avoiding the collision and improvement of wake-up requests. Successful wake-up efficiency and reduce interference to normal communication on the same channel. In addition, this application can better reduce data conflicts when the network traffic is heavy, according to the characteristics of the constantly changing traffic in the network, adaptively adjust to reduce the overall energy consumption of the wireless sensor network, and improve the real-time data transmission , To meet the application requirements in the field of wireless sensor networks.

BRIEF DESCRIPTION

1 is a flowchart of an asynchronous wireless wake-up method provided by this application;

2 is a wireless wake-up interaction process between the wireless sensor network device and the aggregation node provided by this application;

FIG. 3 is a flowchart of a backoff time selection algorithm provided by this application;

4 is a schematic structural diagram of a communication device provided by this application;

5 is a schematic structural diagram of a node provided by this application.

detailed description

The preferred embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

FIG. 1 is a flowchart of an asynchronous wireless wake-up method provided by this application. The reasons for packet loss are divided into busy channel and data collision. The average delay, energy consumption per second, packet loss rate and other indicators are used to analyze the protocol performance. S1: Establish the probability model of secondary collision of the channel, estimate the packet loss rate α, the delay time T _A and the total average energy consumption E _A caused by the node busy channel and wake-up request collision detected by the wireless network; S2: Adaptive selection by establishing a threshold Mechanism to update the threshold sequence of the terminal node; S3: when the data is successfully sent or the upper limit of the number of retransmissions is recorded, the current backoff times BN and backoff index BE are recorded; when the node wakes up the receiver to match the address error, the backoff timer is reset and performed The next back-off stage; and calculate the current average transmission load size DS and other parameters to update the terminal nodes in the network.

S1, establish the channel second collision probability model

Use the Markov chain M/G/1/2 queue model that considers the exponential distribution of service times, introduce secondary collision and finite queue factors, and use C _T (MCU state transition time/CCA detection time, rounded) times short CCA idle channel detection evaluates the channel status and can quickly back off when it detects that the channel is busy. Considering that the wake-up module based on sub-carrier modulation and the main transceiver module share the same antenna to communicate on the same channel to increase the transmission range of the wake-up request, the channel second collision probability model is obtained:

Among them, C _T is the initial value of the CCA channel detection timer, α is the probability of detecting a channel busy after the C _T channel detection is performed, N represents the number of nodes, including N-1 terminal nodes and 1 sink node, E[ Γ] is the total number of data packets sent by the node until the last data is sent, T _CCA is the time required for the idle channel detection, T _ta is the time for successfully transmitting data to occupy the channel, and T _tc is the time for occupying the channel when data transmission collides , Λ is the average arrival rate of data packets; D(k) is the number of channel detections used to detect the busy channel during the k+1 backoff, and c(k) is the probability that the wake-up request is not successfully sent until the k+1 time, d(k) is the probability that a wake-up request is not sent until the k+1th time but a collision occurs, which can be expressed as:

c(k)=α ^k (1-β), d(k)=α ^k δ(1-α)

Where k is the current number of backoffs, M is the maximum number of retransmissions allowed by the node, β=α+δ(1-α) is the sum of channel busy probability and collision probability, and δ(1-α) is generated after the wake-up request is sent The probability of collision, c _sum is the _sum of the average probability of successfully sending data, and d _sum is the _sum of the average probability of collision when data is sent, which are expressed as:

E[D _HoL ] is the average delay from the start of a node's backoff window to sending data or reaching the upper limit of the number of retransmissions, which can be expressed as:

Among them, _PLA means the probability that M+1 times of channel detection are all busy; α ₀ means that no other data packets are generated in the process of sending data by the terminal node, this probability is equal to:

Where w _k is the back-off time and the average time spent on channel detection, which can be expressed as:

The probability that more than two nodes simultaneously perform channel idle detection is expressed as:

δ＝1-P _SC ^N-2 ,

Among them, T _slot is the sum of the electromagnetic wave transmission delay, CCA detection time and the switching delay of the transceiver section, T _CCA time to perform a channel detection CCA, w _k is the back-off time and the average time spent on channel detection; δ is detected when the channel is idle Probability, T _TA is the time required to send data, including the time occupied by the channel and the unoccupied time, expressed as: T _TA = T _wuc + T _on + T _h + T _l + T _SIFS + T _ACK , where T _wuc To wake up request transmission time, T _on is the time required for the MCU to switch from the sleep state to the normal working state, T _h is the time required for the data header transmission, T _l is the time required for the data field transmission, T _SIFS is the frame interval, T _ACK is the time required to confirm the frame transmission;

The average delay of sending data after waking up is expressed as:

T _A =(1-β ^M+1 )T _S +α ^M+T E _L +(β ^M+1 -α ^M+1 )T _C

Calculate the probability that each occurrence of the counter value is not 0 in M+1 times:

Where the probability of each collision accounts for the total probability

P _B = 1-P _C ,

It means that there are k+1-v times out of k+1 times that were not detected for the first time in the channel detection phase, but the channel was detected as busy before C _{T is} reduced to 0, and T _L is the time it takes to reach the upper limit of the number of retransmissions. Expressed as:

Among them, T _BO is the unit time consumed by back-off, W _k is the upper limit of back-off time during the k-th back-off; T _S is the back-off and channel detection time required to successfully send data, and T _C is the time consumed by collision when sending data, P _LA is the probability that all M+1 detection channels are busy, so T _S and T _C are expressed as:

Among them, T _TC is the time it takes to generate a secondary collision after sending data; similarly, the total average energy consumption E _{A of} backoff, channel detection and data transmission is expressed as:

E _A = (1-β ^M+1 )E _S +α ^M+1 E _L +(β ^M+1 -α ^M+1 )E _C

Among them, E _L is the energy consumed to reach the upper limit of the number of retransmissions, expressed as:

Among them, E _BO is the energy consumed for back-off, E _CCA is the energy consumed for performing a channel detection; E _S is the energy for back-off and channel detection required to successfully send data, and E _C is the energy consumed for collision when sending data, respectively for:

Among them, E _HoL is the energy consumed from the arrival of the data packet to the successful transmission, the energy consumed by the E _L backoff reaching the upper limit of the number of discarded data packets, E _TA is the energy consumed by the data during transmission, and E _TC is the data transmission The energy consumed when a collision occurs, P _LB is the probability and the probability of a second collision when the channel is busy and the channel detects idle when M+1 times of detection;

The comprehensive indicators of energy efficiency and packet loss rate are expressed as:

Among them, T _l is the time required to send the data load, W _factor is the energy efficiency weighting factor, P _LA is the probability that the M+1 detection channel is busy; Finally, the terminal node will be based on the current state of the channel, delay, packet loss rate And record information to select the protocol and back-off window size to be used when the next wake-up request is sent.

S2. Establish a threshold adaptive selection mechanism

1) When the number of wake-up request retransmissions increases, node status analysis is performed; if the collision probability of the wake-up request increases, the back-off index BE is increased according to the efficiency curve; if the collision probability of the wake-up request decreases, the back-off index is decreased. According to the adjusted backoff index, a threshold sequence TS is generated.

2) When the identifier is detected as 1, the back-off timer is reset, the next stage of back-off is performed, and the identifier is cleared.

S3. The terminal node first initializes the current backoff times BN to 1, and each time the backoff times BN increases by 1. The value of the initial back-off index BE is CBE. The node first obtains the current backoff times BN. If it is less than the threshold TS(BN), the direct channel detection mode is used; if it is greater than the threshold TS(BN), the node performs backoff first, and enters the channel detection state when the backoff timer is zero. The terminal node uses multiple short-term idle channel detections, and C _T decrements each time the detection is completed. When the C _T value is 0, it represents the end of the channel detection phase. If one of them detects that the channel is busy, it is considered that other nodes are currently communicating, and the next back-off process needs to be performed until the number of back-off times BN is greater than the maximum number of attempts. When all the tests show that the channel is idle, it means that the node can perform the operation of sending a wake-up request, as shown in Table 1.

Table I

Each time data is successfully transmitted or the upper limit of the number of retransmissions is reached, the current back-off times and back-off index are recorded, and the back-off times of the data sent in recent times are used to calculate W _BN through a weighting algorithm. And when the wake-up transceiver WuR of the terminal node has received the wake-up information of other nodes before, the identifier is set to 1, indicating that other nodes are currently transmitting data to increase the back-off time. Consider weighted calculation of the number of backoffs used for historical transmission data, thus obtaining the formula:

W _BN = θ ₁ BN ₁ +θ ₂ BN ₂ +θ ₃ BN ₃ +θ ₄ BN ₄ +θ ₅ BN ₅

The node records the number of back-off times BN required for each successful data transmission, and calculates the value of W _BN by linear weighting according to the number of back-off times required in the last few times. The smaller the subscript number, the closer the time is to the current time, and θ represents the weighting factor coefficient of each backoff number. The closer the time, the larger the coefficient.

FIG. 2 is a wireless wake-up interaction process between the wireless sensor network device and the aggregation node adopted in this embodiment. The first terminal node detects that the channel is idle after a random backoff time, wakes up the sink node and starts communication. The second terminal node backoff counter is 0, and it may also detect that the channel is idle when the sink node switches to wait or when it is simultaneously detected with other nodes, and then send a wake-up request, resulting in data collision. Therefore, multiple consecutive short-term CCA detections are used to flexibly evaluate the channel idle state, which can enter dormancy faster and reduce energy consumption.

Figure 3 is a flowchart of the backoff time selection algorithm. When a node has a data message to send, it first uses WuR to query its own WBN and CBE value status, and then selects the back-off index BE based on these stored historical communication information. This value may be different in each communication. Then wait for the backoff counter value to decrease to 0, using multiple short-term idle channel detection. When a channel is detected as busy in continuous channel detection, it indicates that the channel is currently busy and directly enters the next back-off phase, BN=BN+1. If the channel is idle at the end of multiple idle channel detections at this stage, you can select the optimal rate to send the wake-up request according to the packet size. After the sink node receives the complete wake-up request and successfully matches the address, it wakes up the MCU to perform normal data reception work, and other terminal nodes will mark position 1 when received. After the transmission is completed, wait for the aggregation node to return the data message to confirm. After receiving the ACK, the communication ends and immediately enters the sleep state. If the node detects that the channel is busy or does not receive an ACK, it should recalculate the BN and BE values and proceed to the next stage.

Each node in the network has an independent sending probability. When the number of nodes increases, the number of data packets to be sent in the network will increase, and the probability of collision will also increase. The common protocol does not consider the data transmission collision caused by the delay of the device state switching; CSMA-WuR uses long-term channel detection to reduce the occurrence of collisions; CSMAO-WuR is based on the former protocol, and the channel detection duration has been dynamically changed. To make it more sensitive and reduce collision; DNAP-WuR adaptively selects the back-off window according to the performance index, which reduces the collision probability and improves real-time performance.

It can be understood that when the above node is used for asynchronous wireless wakeup, in order to realize the above function, it includes a hardware structure and/or a software module corresponding to each function. In this application, the node device is also simply referred to as a device, or a device for asynchronous wireless wakeup. Those skilled in the art should easily realize that, in combination with the example modules and algorithm steps described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed by hardware or computer software driven hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

Described in terms of hardware structure, the nodes in FIGS. 1 to 3 may be implemented by one physical device, or may be implemented by multiple physical devices together, or may be a logical function module in a physical device. No specific restrictions.

For example, it can be realized by the communication device in FIG. 4. 4 is a schematic diagram of the hardware structure of a node provided by an embodiment of the present application. It includes: a communication interface 401 and a processor 402, and may also include a memory 403.

The communication interface 401 can use any device such as a transceiver to communicate with other devices or communication networks, such as Ethernet, wireless access network (RAN), wireless local area networks (WLAN), etc. .

The processor 402 includes but is not limited to a central processing unit (CPU), a network processor (NP), an application-specific integrated circuit (ASIC), or a programmable logic device (programmable logic device, One or more of PLD). The PLD may be a complex programmable logic device (complex programmable logic device (CPLD), field programmable gate array (FPGA), general array logic (GAL) or any combination thereof. The processor 402 is responsible for the communication line 404 and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. The memory 403 may be used to store data used by the processor 402 when performing operations.

The memory 403 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (random access memory, RAM), or other types of information and instructions that can be stored The dynamic storage device can also be an electrically erasable programmable read-only memory (electrically programmable server-programmable read-only memory, EEPROM), a compact disc-read-only memory (CD-ROM) or other optical disc storage, optical disc Storage (including compact discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or can be used to carry or store the desired program code in the form of instructions or data structures and can be used by Any other media accessed by the computer, but not limited to this. The memory may exist independently, and is connected to the processor 402 through the communication line 404. The memory 403 may also be integrated with the processor 402. If the memory 403 and the processor 402 are independent devices, the memory 403 and the processor 402 are connected, for example, the memory 403 and the processor 402 can communicate through a communication line. The communication interface 401 and the processor 402 can communicate through a communication line, and the communication interface 401 can also be directly connected to the processor 402.

The communication line 404 may include any number of interconnected buses and bridges. The communication line 404 links various circuits including one or more processors 402 represented by the processor 402 and a memory represented by the memory 403 together. The communication line 404 may also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, etc., which are well known in the art, and therefore, they will not be further described in this application.

In a specific embodiment, the node may include:

Memory, used to store computer-readable instructions;

It also includes a processor coupled to the memory for executing computer-readable instructions in the memory to perform the following operations:

Establish a channel second collision probability model to estimate the packet loss rate α, delay time T _A and total average energy consumption E _A monitored by nodes in the wireless network;

By establishing a threshold adaptive selection mechanism, the threshold sequence of the terminal node is updated;

Also includes a communication interface for sending and receiving data;

The processor is also used to record the current backoff times BN and backoff index BE when the communication interface successfully sends data or reaches the upper limit of the number of retransmissions, and when the node wakes up the receiver to match the address error, reset the backoff timer to proceed In the next backoff stage, the current average transmission load size DS is calculated to update the terminal nodes in the network.

In a specific embodiment, the processor is specifically used to:

Use the Markov chain M/G/1/2 queue model, introduce secondary collision and finite queue factors, and use C _T short idle channel detection CCA to evaluate the channel state to obtain the secondary collision probability model:

Among them, C _T is the initial value of the CCA channel detection timer, α is the probability of detecting a channel busy after the C _T channel detection is performed, N represents the number of nodes, including N-1 terminal nodes and 1 sink node, E[ Γ] is the total number of data packets sent by the node until the last data is sent. T _CCA is the time to perform a channel detection CCA, T _ta is the time to successfully send data to occupy the channel, and T _tc is the time to occupy the channel when the data is sent to collide , Λ is the average arrival rate of data packets, E[D _HoL ] is the average delay from the start of the node backoff window to sending data or reaching the upper limit of the number of retransmissions, D(k) is used to detect the busy channel during the k+1 backoff The number of channel detections, c(k) is the probability that the wake-up request is not successfully sent until the k+1th time, and d(k) is the probability that the wake-up request is not sent until the k+1th time but a collision occurs, expressed as:

c(k)=α ^k (1-β), d(k)=α ^k δ(1-α)

Where k is the current number of backoffs, M is the maximum number of retransmissions allowed by the node, β=α+δ(1-α) is the sum of channel busy probability and collision probability, and δ(1-α) is generated after the wake-up request is sent The probability of collision, c _sum is the _sum of the average probability of successfully sending data, and d _sum is the _sum of the average probability of collision when data is sent, which are expressed as:

The probability that more than two nodes simultaneously perform channel idle detection is expressed as:

δ＝1-P _SC ^N-2 ,

Among them, T _slot is the sum of the electromagnetic wave transmission delay, CCA detection time and the switching delay of the transceiver section, T _CCA is the time to perform a channel detection CCA, w _k is the back-off time and the average time spent on channel detection, and δ is the detection of channel idle Probability, T _TA is the time required to send data, including the time occupied by the channel and the unoccupied time, expressed as: T _TA = T _wuc + T _on + T _h + T _l + T _SIFS + T _ACK , where, T _wuc is the wake-up request transmission time, T _on is the time required for the MCU to switch from the sleep state to the normal working state, T _h is the time required for the data header transmission, T _l is the time required for the data field transmission, and T _SIFS is the frame interval , T _ACK is the time required to confirm the frame transmission;

The average delay of sending data after waking up is expressed as:

T _A =(1-β ^M+1 )T _S +α ^M+1 T _L +(β ^M+1 -α ^M+1 )T _C

Calculate the probability that each occurrence of the counter value is not 0 in M+1 times:

Where the probability of each collision accounts for the total probability

P _B = 1-P _C ,

It means that there are k+1-v times out of k+1 times that were not detected for the first time in the channel detection phase, but the channel was detected as busy before C _{T is} reduced to 0, and T _L is the time it takes to reach the upper limit of the number of retransmissions. Expressed as:

Among them, T _BO is the unit time consumed by back-off, W _k is the upper limit of back-off time during the k-th back-off, T _S is the back-off and channel detection time required to successfully send data, and T _C is the time consumed by collision when sending data, T _S and T _C are expressed as:

Among them, T _TC is the time it takes to generate a secondary collision after sending data, and the total average energy consumption E _{A of} back-off, channel detection, and data transmission is expressed as:

E _A = (1-β ^M+1 )E _S +α ^M+1 E _L +(β ^M+1 -α ^M+1 )E _C

Among them, E _L is the energy consumed to discard the data packet when the upper limit of the number of retransmissions is reached, expressed as:

Among them, E _BO is the energy consumed for back-off, E _CCA is the energy consumed for performing a channel detection, E _S is the energy for back-off and channel detection required to successfully send data, and E _C is the energy consumed for collision when sending data, respectively for:

Among them, E _HoL is the energy consumed from the arrival of the data packet to the successful transmission, the energy consumed by the E _L backoff reaching the upper limit of the number of discarded data packets, E _TA is the energy consumed by the data during transmission, and E _TC is the data transmission The energy consumed when a collision occurs, P _LB is the probability and the probability of a second collision when the channel is busy and the channel detects idle when M+1 times of detection;

The comprehensive indicators of energy efficiency and packet loss rate are expressed as:

Among them, T _l is the time required to send the data load, W _factor is the energy efficiency weighting factor, and P _LA is the probability that M+1 detection channels are busy;

According to the current state of the channel, delay, packet loss rate and record information, select the protocol and back-off window size to be used for the next wake-up request.

In a specific embodiment, the processor is specifically used to:

When the number of wake-up request retransmissions increases, perform node status analysis;

If the collision probability of the wake-up request increases, the back-off index BE is increased according to the efficiency curve. If the collision probability of the wake-up request decreases, the back-off index is reduced, and a threshold sequence TS is generated according to the adjusted back-off index;

When the identifier is detected as 1, the back-off timer is reset, the next stage of back-off is performed, and the identifier is cleared.

In a specific embodiment, the processor is specifically used to:

Initialize the current backoff times BN to 1, each time the backoff times BN increases by 1, the initial backoff index BE value is CBE;

Obtain the current backoff times BN. If it is less than the threshold TS, the direct channel detection mode is used. If it is greater than the threshold TS, the backoff is performed first. When the backoff timer is 0, the channel detection state is entered. The terminal node adopts no less than one short-term idle For channel detection, C _T decrements every time the detection is completed _{. When the} value of C _T is 0, it represents the end of the channel detection phase;

If one of them detects that the channel is busy, it is considered that there are other nodes currently communicating, and the next back-off process is performed until the number of back-off times BN is greater than the maximum number of attempts;

When all the tests show that the channel is idle, it represents the operation of sending a wake-up request on behalf of the node;

Each time data is successfully transmitted or the upper limit of the number of retransmissions is reached, the current backoff times and backoff index are recorded, and the backoff times of the data sent in recent times are used to calculate W _BN through a weighting algorithm,

When the wake-up transceiver WuR of the terminal node has previously received the wake-up information of other nodes, the identifier is set to 1, indicating that other nodes are currently transmitting data to increase the back-off time, and the formula is obtained:

W _BN = θ ₁ BN ₁ +θ ₂ BN ₂ +θ ₃ BN ₃ +θ ₄ BN ₄ +θ ₅ BN ₅

Among them, the smaller the subscript number indicates that the time is closer to the current time, θ indicates the weighting factor coefficient of each backoff times, and W _BN indicates the historical weighted backoff times.

In a specific embodiment, the processor is also used to:

When analyzing the cause of collision, the adaptive modification of different protocols is carried out based on the channel second collision probability model.

In a specific embodiment, the communication interface is also used for:

Use the wake-up transceiver WuR and the main transceiver MCU, and WuR and MCU use different frequencies for communication.

In the embodiments of the present application, the communication interface may be regarded as a node's transceiver unit, a processor with a processing function as a node's processing unit, and a memory as a node's storage unit. As shown in FIG. 5, the node includes a transceiver unit 510 and a processing unit 520. The transceiver unit may also be called a transceiver, a transceiver, a transceiver device, or the like. The processing unit may also be called a processor, a processing board, a processing module, a processing device, and the like. Optionally, the device used to implement the receiving function in the transceiver unit 510 may be regarded as a receiving unit, and the device used to implement the sending function in the transceiver unit 510 may be regarded as a sending unit, that is, the transceiver unit 510 includes a receiving unit and a sending unit. The transceiver unit may sometimes be called a transceiver, a transceiver, or a transceiver circuit. The receiving unit may sometimes be called a receiver, a receiver, or a receiving circuit. The sending unit may sometimes be called a transmitter, a transmitter, or a transmitting circuit.

In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product.

The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the processes or functions according to the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a dedicated computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be from a website site, computer, server or data center Transmit to another website, computer, server or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be stored by a computer or a data storage device including a server, a data center, and the like integrated with one or more available media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, Solid State Disk (SSD)) or the like.

A person of ordinary skill in the art may understand that all or part of the steps in the various methods of the foregoing embodiments may be completed by instructing relevant hardware through a program. The program may be stored in a computer-readable storage medium, and the storage medium may include: ROM, RAM, magnetic disk or optical disk, etc.

Claims (20)

1. An asynchronous wireless wake-up method, characterized in that it includes:

   Establish a channel second collision probability model to estimate the packet loss rate α, delay time T _A and total average energy consumption E _A monitored by nodes in the wireless network;

   By establishing a threshold adaptive selection mechanism, the threshold sequence of the terminal node is updated;

   When the data is successfully sent or the upper limit of the number of retransmissions is reached, the current backoff times BN and backoff index BE are recorded. When the node wakes up the receiver to match the address error, the backoff timer is reset, the next backoff stage is performed, and the current average transmission load size is calculated DS updates the end nodes in the network.
2. The method according to claim 1, wherein the establishing a channel second collision probability model to estimate the packet loss rate α, the delay time T _A and the total average energy consumption E _A monitored by the nodes in the wireless network includes:

   Use the Markov chain M/G/1/2 queue model, introduce secondary collision and finite queue factors, and use C _T short idle channel detection CCA to evaluate the channel state to obtain the secondary collision probability model:

   

   

   Among them, C _T is the initial value of the CCA channel detection timer, α is the probability of detecting a channel busy after the C _T channel detection is performed, N represents the number of nodes, including N-1 terminal nodes and 1 sink node, E[ Γ] is the total number of data packets sent by the node until the last data is sent, T _CCA is the time to perform a channel detection CCA, T _ta is the time to successfully send data to occupy the channel, and T _tc is the time to occupy the channel when the data is sent to collide , Λ is the average packet arrival rate, E[D _HoL ] is the average delay from the start of the node backoff window to sending data or reaching the upper limit of the number of retransmissions, D(k) is used to detect the busy channel during the k+1 backoff The number of channel detections, c(k) is the probability that the wake-up request is not successfully sent until the k+1 time, and d(k) is the probability that the wake-up request is not sent until the k+1 time but a collision occurs, expressed as:

   c(k)=α ^k (1-β), d(k)=α ^k δ(1-α)

   Where k is the current number of backoffs, M is the maximum number of retransmissions allowed by the node, β=α+δ(1-α) is the sum of channel busy probability and collision probability, and δ(1-α) is generated after the wake-up request is sent The probability of collision, c _sum is the _sum of the average probability of successfully sending data, and d _sum is the _sum of the average probability of collision when data is sent, which are expressed as:

   

   The probability that more than two nodes simultaneously perform channel idle detection is expressed as:

   

   Among them, T _slot is the sum of the electromagnetic wave transmission delay, CCA detection time and the switching delay of the transceiver section, T _CCA is the time to perform a channel detection CCA, w _k is the back-off time and the average time spent on channel detection, and δ is the detection of channel idle Probability, T _TA is the time required to send data, including the time occupied by the channel and the unoccupied time, expressed as: T _TA = T _wuc + T _on + T _h + T _l + T _SIFS + T _ACK , where, T _wuc is the wake-up request transmission time, T _on is the time required for the MCU to switch from the sleep state to the normal working state, T _h is the time required for the data header transmission, T _l is the time required for the data field transmission, and T _SIFS is the frame interval , T _ACK is the time required to confirm the frame transmission;

   The average delay of sending data after waking up is expressed as:

   T _A =(1-β ^M+1 )T _S +α ^M+1 T _L +(β ^M+1 -α ^M+1 )T _C

   Calculate the probability that each occurrence of the counter value is not 0 in M+1 times:

   

   Where the probability of each collision accounts for the total probability

   

   P _B = 1-P _C ,

   

   It means that there are k+1-v times out of k+1 times that were not detected for the first time in the channel detection phase, but the channel was detected as busy before C _{T is} reduced to 0, and T _L is the time it takes to reach the upper limit of the number of retransmissions. Expressed as:

   

   Among them, T _BO is the unit time consumed by back-off, W _k is the upper limit of back-off time during the k-th back-off, T _S is the back-off and channel detection time required to successfully send data, and T _C is the time consumed by collision when sending data, T _S and T _C are expressed as:

   

   Among them, T _TC is the time it takes to generate a secondary collision after sending data, and the total average energy consumption E _{A of} back-off, channel detection, and data transmission is expressed as:

   E _A = (1-β ^M+1 )E _S +α ^M+1 E _L +(β ^M+1 -α ^M+1 )E _C

   Among them, E _L is the energy consumed to discard the data packet when the upper limit of the number of retransmissions is reached, expressed as:

   

   Among them, E _BO is the energy consumed for back-off, E _CCA is the energy consumed for performing a channel detection; E _S is the energy for back-off and channel detection required to successfully send data, and E _C is the energy consumed for collision when sending data, respectively for:

   

   Among them, E _HoL is the energy consumed from the arrival of the data packet to the successful transmission, the energy consumed by the E _L backoff reaching the upper limit of the number of discarded data packets, E _TA is the energy consumed by the data during transmission, and E _TC is the data transmission The energy consumed when a collision occurs, P _LB is the probability and the probability of a second collision when the channel is busy and the channel detects idle when M+1 times of detection;

   The comprehensive indicators of energy efficiency and packet loss rate are expressed as:

   

   Among them, T _l is the time required to send the data load, W _factor is the energy efficiency weighting factor, and P _LA is the probability that M+1 detection channels are busy;

   According to the current state of the channel, delay, packet loss rate and record information, select the protocol and back-off window size to be used for the next wake-up request.
3. The method according to claim 1, wherein the updating of the threshold sequence of the terminal node by establishing a threshold adaptive selection mechanism includes:

   When the number of wake-up request retransmissions increases, perform node status analysis;

   If the collision probability of the wake-up request increases, the back-off index BE is increased according to the efficiency curve. If the collision probability of the wake-up request decreases, the back-off index is reduced, and a threshold sequence TS is generated according to the adjusted back-off index;

   When the identifier is detected as 1, the back-off timer is reset, the next stage of back-off is performed, and the identifier is cleared.
4. The method according to claim 2, wherein when the data is successfully sent or the upper limit of the number of retransmissions is reached, the current backoff times BN and backoff index BE are recorded, and the backoff timer is reset when the node wakes up the receiver to match the address error Perform the next back-off phase and calculate the current average transmission load size DS to update the terminal nodes in the network, including:

   Initialize the current backoff times BN to 1, each time the backoff times BN increases by 1, the initial backoff index BE value is CBE;

   Obtain the current backoff times BN. If it is less than the threshold TS, the direct channel detection mode is used. If it is greater than the threshold TS, the backoff is performed first. When the backoff timer is 0, the channel detection state is entered. The terminal node adopts no less than one short-term idle For channel detection, C _T decrements every time the detection is completed _{. When the} value of C _T is 0, it represents the end of the channel detection phase;

   If one of them detects that the channel is busy, it is considered that there are other nodes currently communicating, and the next back-off process is performed until the number of back-off times BN is greater than the maximum number of attempts;

   When all the tests show that the channel is idle, it represents the operation of sending a wake-up request on behalf of the node;

   Each time data is successfully transmitted or the upper limit of the number of retransmissions is reached, the current backoff times and backoff index are recorded, and the backoff times of the data sent in recent times are used to calculate W _BN through a weighting algorithm,

   When the wake-up transceiver WuR of the terminal node has previously received the wake-up information of other nodes, the identifier is set to 1, indicating that other nodes are currently transmitting data to increase the back-off time, and the formula is obtained:

   W _BN = θ ₁ BN ₁ +θ ₂ BN ₂ +θ ₃ BN ₃ +θ ₄ BN ₄ +θ ₅ BN ₅

   Among them, the smaller the subscript number indicates that the time is closer to the current time, θ indicates the weighting factor coefficient of each backoff times, and W _BN indicates the historical weighted backoff times.
5. The method of claim 2, further comprising:

   When analyzing the cause of collision, the adaptive modification of different protocols is carried out based on the channel second collision probability model.
6. The method according to claim 3, further comprising:

   Both the sink node and the terminal node use the wake-up transceiver WuR and the main transceiver MCU, and WuR and MCU use different frequencies for communication, respectively.
7. A device for asynchronous wireless wake-up, characterized in that it includes:

   The processing unit is used to establish a second collision probability model of the channel and estimate the packet loss rate α, the delay time T _A and the total average energy consumption E _A monitored by the nodes in the wireless network;

   The processing unit is also used to update the threshold sequence of the terminal node by establishing a threshold adaptive selection mechanism;

   Transceiver unit, used to send and receive data;

   The processing unit is also used to record the current backoff times BN and backoff index BE when the sending and receiving unit successfully sends data or reaches the upper limit of the number of retransmissions, and when the node wakes up the receiver to match the address error, reset the backoff timer to proceed In the next backoff stage, the current average transmission load size DS is calculated to update the terminal nodes in the network.
8. The device according to claim 7, wherein the processing unit is specifically configured to:

   Use the Markov chain M/G/1/2 queue model, introduce secondary collision and finite queue factors, and use C _T short idle channel detection CCA to evaluate the channel state to obtain the secondary collision probability model:

   

   

   Among them, C _T is the initial value of the CCA channel detection timer, α is the probability of detecting a channel busy after the C _T channel detection is performed, N represents the number of nodes, including N-1 terminal nodes and 1 sink node, E[ Γ] is the total number of data packets sent by the node until the last data is sent, T _CCA is the time to perform a channel detection CCA, T _ta is the time to successfully send data to occupy the channel, and T _tc is the time to occupy the channel when the data is sent to collide , Λ is the average packet arrival rate, E[D _HoL ] is the average delay from the start of the node backoff window to sending data or reaching the upper limit of the number of retransmissions, D(k) is used to detect the busy channel during the k+1 backoff The number of channel detections, c(k) is the probability that the wake-up request is not successfully sent until the k+1 time, and d(k) is the probability that the wake-up request is not sent until the k+1 time but a collision occurs, expressed as:

   c(k)=α ^k (1-β), d(k)=α ^k δ(1-α)

   Where k is the current number of backoffs, M is the maximum number of retransmissions allowed by the node, β=α+δ(1-α) is the sum of channel busy probability and collision probability, and δ(1-α) is generated after the wake-up request is sent The probability of collision, c _sum is the _sum of the average probability of successfully sending data, and d _sum is the _sum of the average probability of collision when data is sent, which are expressed as:

   

   The probability that more than two nodes simultaneously perform channel idle detection is expressed as:

   

   Among them, T _slot is the sum of electromagnetic wave transmission delay, CCA detection time and the switching delay of the transceiver section, T _CCA is the time to perform a channel detection CCA, w _k is the back-off time and the average time spent on channel detection, and δ is the detection of channel idle Probability, T _TA is the time required to send data, including the time occupied by the channel and the unoccupied time, expressed as: T _TA = T _wuc + T _on + T _h + T _l + T _SIFS + T _ACK where, T _wuc is the wake-up request transmission time, T _on is the time required for the MCU to switch from the sleep state to the normal working state, T _h is the time required for the data header transmission, T _l is the time required for the data field transmission, and T _SIFS is the frame interval, T _ACK is the time required to confirm the frame transmission;

   The average delay of sending data after waking up is expressed as:

   T _A =(1-β ^M+1 )T _S +α ^M+1 T _L +(β ^M+1 -α ^M+1 )T _C

   Calculate the probability that each occurrence of the counter value is not 0 in M+1 times:

   

   Where the probability of each collision accounts for the total probability

   

   P _B = 1-P _C ,

   

   It means that there are k+1-v times out of k+1 times that were not detected for the first time in the channel detection phase, but the channel was detected as busy before C _{T is} reduced to 0, and T _L is the time it takes to reach the upper limit of the number of retransmissions. Expressed as:

   

   Among them, T _BO is the unit time consumed by back-off, W _k is the upper limit of back-off time during the k-th back-off, T _S is the back-off and channel detection time required to successfully send data, and T _C is the time consumed by collision when sending data, T _S and T _C are expressed as:

   

   Among them, T _TC is the time it takes to generate a secondary collision after sending data, and the total average energy consumption E _{A of} back-off, channel detection, and data transmission is expressed as:

   E _A = (1-β ^M+1 )E _S +α ^M+1 E _L +(β ^M+1 -α ^M+1 )E _C

   Among them, E _L is the energy consumed to discard the data packet when the upper limit of the number of retransmissions is reached, expressed as:

   

   Among them, E _BO is the energy consumed for back-off, E _CCA is the energy consumed for performing a channel detection, E _S is the energy for back-off and channel detection required to successfully send data, and E _C is the energy consumed for collision when sending data, respectively for:

   

   Among them, E _HoL is the energy consumed from the arrival of the data packet to the successful transmission, the energy consumed by the E _L backoff reaching the upper limit of the number of discarded data packets, E _TA is the energy consumed by the data during transmission, and E _TC is the data transmission The energy consumed when a collision occurs, P _LB is the probability and the probability of a second collision when the channel is busy and the channel detects idle when M+1 times of detection;

   The comprehensive indicators of energy efficiency and packet loss rate are expressed as:

   

   Among them, T _l is the time required to send the data load, W _factor is the energy efficiency weighting factor, and P _LA is the probability that M+1 detection channels are busy;

   According to the current state of the channel, delay, packet loss rate and record information, select the protocol and back-off window size to be used for the next wake-up request.
9. The device according to claim 7, wherein the processing unit is specifically configured to:

   When the number of wake-up request retransmissions increases, perform node status analysis;

   If the collision probability of the wake-up request increases, the back-off index BE is increased according to the efficiency curve. If the collision probability of the wake-up request decreases, the back-off index is reduced, and a threshold sequence TS is generated according to the adjusted back-off index;

   When the identifier is detected as 1, the back-off timer is reset, the next stage of back-off is performed, and the identifier is cleared.
10. The device according to claim 8, wherein the processing unit is specifically configured to:

    Initialize the current backoff times BN to 1, each time the backoff times BN increases by 1, the initial backoff index BE value is CBE;

    Obtain the current backoff times BN. If it is less than the threshold TS, the direct channel detection mode is used. If it is greater than the threshold TS, the backoff is performed first. When the backoff timer is 0, the channel detection state is entered. The terminal node adopts no less than one short-term idle For channel detection, C _T decrements every time the detection is completed _{. When the} value of C _T is 0, it represents the end of the channel detection phase;

    If one of them detects that the channel is busy, it is considered that there are other nodes currently communicating, and the next back-off process is performed until the number of back-off times BN is greater than the maximum number of attempts;

    When all the tests show that the channel is idle, it represents the operation of sending a wake-up request on behalf of the node;

    Each time data is successfully transmitted or the upper limit of the number of retransmissions is reached, the current backoff times and backoff index are recorded, and the backoff times of the data sent in recent times are used to calculate W _BN through a weighting algorithm;

    When the wake-up transceiver WuR of the terminal node has received the wake-up information of other nodes before, the identifier is set to 1, indicating that there are other nodes currently transmitting data to increase the back-off time to obtain the formula:

    W _BN = θ ₁ BN ₁ +θ ₂ BN ₂ +θ ₃ BN ₃ +θ ₄ BN ₄ +θ ₅ BN ₅

    Among them, the smaller the subscript number indicates that the time is closer to the current time, θ indicates the weighting factor coefficient of each backoff times, and W _BN indicates the historical weighted backoff times.
11. The device according to claim 8, wherein the processing unit is further configured to:

    When analyzing the cause of collision, the adaptive modification of different protocols is carried out based on the channel second collision probability model.
12. The device according to claim 9, wherein the transceiver unit is further configured to:

    Use the wake-up transceiver WuR and the main transceiver MCU, and WuR and MCU use different frequencies for communication.
13. A device for asynchronous wireless wake-up, characterized in that it includes:

    Memory, used to store computer-readable instructions;

    It also includes a processor coupled to the memory for executing computer-readable instructions in the memory to perform the following operations:

    Establish a channel second collision probability model to estimate the packet loss rate α, delay time T _A and total average energy consumption E _A monitored by nodes in the wireless network;

    By establishing a threshold adaptive selection mechanism, the threshold sequence of the terminal node is updated;

    Also includes a communication interface for sending and receiving data;

    The processor is also used to record the current backoff times BN and backoff index BE when the communication interface successfully sends data or reaches the upper limit of the number of retransmissions, and when the node wakes up the receiver to match the address error, reset the backoff timer to proceed In the next back-off stage, the current average transmission load size DS is calculated to update the terminal nodes in the network.
14. The device according to claim 13, wherein the processor is specifically configured to:

    Use the Markov chain M/G/1/2 queue model, introduce secondary collision and finite queue factors, and use C _T short idle channel detection CCA to evaluate the channel state to obtain the secondary collision probability model:

    

    

    Where C _T is the initial value of the CCA channel detection timer, α is the probability of detecting a busy channel after the C _T channel detection is performed, N represents the number of nodes, including N-1 terminal nodes and 1 sink node, E[ Γ] is the total number of data packets sent by the node until the last data is sent, T _CCA is the time for performing a channel detection CCA, T _ta is the time for successfully sending data to occupy the channel, and T _tc is the time for occupying the channel when a data transmission collision occurs , Λ is the average arrival rate of data packets, E[D _HoL ] is the average delay from the start of the node backoff window to sending data or reaching the upper limit of the number of retransmissions, and the channel used to detect the busy channel during the k+1 backoff of D(k) Number of detections, c(k) is the probability that the wake-up request is not successfully sent until the k+1th time, and d(k) is the probability that the wake-up request is not sent until the k+1th time but a collision occurs, expressed as:

    c(k)=α ^k (1-β), d(k)=α ^k δ(1-α)

    Where k is the current number of backoffs, M is the maximum number of retransmissions allowed by the node, β=α+δ(1-α) is the sum of channel busy probability and collision probability, and δ(1-α) is generated after the wake-up request is sent The probability of collision, c _sum is the _sum of the average probability of successfully sending data, and d _sum is the _sum of the average probability of collision when data is sent, which are expressed as:

    

    The probability that more than two nodes simultaneously perform channel idle detection is expressed as:

    

    Among them, T _slot is the sum of electromagnetic wave transmission delay, CCA detection time and the switching delay of the transceiver section, T _CCA is the time to perform a channel detection CCA, w _k is the back-off time and the average time spent on channel detection, and δ is the detection of channel idle Probability, T _TA is the time required to send data, including the time occupied by the channel and the unoccupied time, expressed as: T _TA = T _wuc + T _on + T _h + T _l + T _SIFS + T _ACK where, T _wuc is the wake-up request transmission time, T _on is the time required for the MCU to switch from the sleep state to the normal working state, T _h is the time required for the data header transmission, T _l is the time required for the data field transmission, and T _SIFS is the frame interval, T _ACK is the time required to confirm the frame transmission;

    The average delay of sending data after waking up is expressed as:

    T _A =(1-β ^M+1 )T _S +α ^M+1 T _L +(β ^M+1 -α ^M+1 )T _C

    Calculate the probability that each occurrence of the counter value is not 0 in M+1 times:

    

    Where the probability of each collision accounts for the total probability

    

    P _B = 1-P _C ,

    

    It means that there are k+1-v times out of k+1 times that were not detected for the first time in the channel detection phase, but the channel was detected as busy before C _{T is} reduced to 0, and T _L is the time it takes to reach the upper limit of the number of retransmissions. Expressed as:

    

    Among them, T _BO is the unit time consumed by back-off, W _k is the upper limit of back-off time during the k-th back-off, T _S is the back-off and channel detection time required to successfully send data, and T _C is the time consumed by collision when sending data, T _S and T _C are expressed as:

    

    Among them, T _TC is the time it takes to generate a secondary collision after sending data, and the total average energy consumption E _{A of} back-off, channel detection, and data transmission is expressed as:

    E _A = (1-β ^M+1 )E _S +α ^M+1 E _L +(β ^M+1 -α ^M+1 )E _C

    Among them, E _L is the energy consumed to discard the data packet when the upper limit of the number of retransmissions is reached, expressed as:

    

    Among them, E _BO is the energy consumed for back-off, E _CCA is the energy consumed for performing a channel detection, E _S is the energy for back-off and channel detection required to successfully send data, and E _C is the energy consumed for collision when sending data, respectively for:

    

    Among them, E _HoL is the energy consumed from the arrival of the data packet to the successful transmission, the energy consumed by the E _L backoff reaching the upper limit of the number of discarded data packets, E _TA is the energy consumed by the data during transmission, and E _TC is the data transmission The energy consumed when a collision occurs, P _LB is the probability and the probability of a second collision when the channel is busy and the channel detects idle when M+1 times of detection;

    The comprehensive indicators of energy efficiency and packet loss rate are expressed as:

    

    Among them, T _l is the time required to send the data load, W _factor is the energy efficiency weighting factor, and P _LA is the probability that M+1 detection channels are busy;

    According to the current state of the channel, delay, packet loss rate and record information, select the protocol and back-off window size to be used for the next wake-up request.
15. The device according to claim 13, wherein the processor is specifically configured to:

    When the number of wake-up request retransmissions increases, perform node status analysis;

    If the collision probability of the wake-up request increases, the back-off index BE is increased according to the efficiency curve. If the collision probability of the wake-up request decreases, the back-off index is reduced, and a threshold sequence TS is generated according to the adjusted back-off index;

    When the identifier is detected as 1, the back-off timer is reset, the next stage of back-off is performed, and the identifier is cleared.
16. The device according to claim 14 in the group, wherein the processor is specifically configured to:

    Initialize the current backoff times BN to 1, each time the backoff times BN increases by 1, the initial backoff index BE value is CBE;

    Obtain the current backoff times BN. If it is less than the threshold TS, the direct channel detection mode is used. If it is greater than the threshold TS, the backoff is performed first. When the backoff timer is 0, the channel detection state is entered. The terminal node adopts no less than one short-term idle For channel detection, C _T decrements every time the detection is completed _{. When the} value of C _T is 0, it represents the end of the channel detection phase;

    If one of them detects that the channel is busy, it is considered that there are other nodes currently communicating, and the next back-off process is performed until the number of back-off times BN is greater than the maximum number of attempts;

    When all the tests show that the channel is idle, it represents the operation of sending a wake-up request on behalf of the node;

    Each time data is successfully transmitted or the upper limit of the number of retransmissions is reached, the current backoff times and backoff index are recorded, and the backoff times of the data sent in recent times are used to calculate W _BN through a weighting algorithm,

    When the wake-up transceiver WuR of the terminal node has previously received the wake-up information of other nodes, the identifier is set to 1, indicating that other nodes are currently transmitting data to increase the back-off time, and the formula is obtained:

    W _BN = θ ₁ BN ₁ +θ ₂ BN ₂ +θ ₃ BN ₃ +θ ₄ BN ₄ +θ ₅ BN ₅

    Among them, the smaller the subscript number indicates that the time is closer to the current time, θ indicates the weighting factor coefficient of each backoff times, and W _BN indicates the historical weighted backoff times.
17. The device according to claim 14, wherein the processor is further configured to:

    When analyzing the cause of collision, the adaptive modification of different protocols is carried out based on the channel second collision probability model.
18. The device according to claim 15, wherein the communication interface is further used for:

    Use the wake-up transceiver WuR and the main transceiver MCU, and WuR and MCU use different frequencies for communication.
19. A computer-readable storage medium, characterized in that, when instructions are executed on a computer device, the computer device is caused to perform the method according to any one of claims 1 to 6.
20. A computer program product, which when run on a computer, enables the computer to execute the method according to any one of claims 1 to 6.

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