Channel access method, apparatus, device, and storage medium

Abstract

The application discloses a channel access method, device, equipment and storage medium, and the method comprises the following steps: obtaining the surrounding node situation information of a target node before the next decision cycle starts or when data packets need to be sent; determining the starting time of the attempt to send window in the next decision cycle according to the surrounding node situation information; and controlling the target node to access the channel when the starting time of the attempt to send window is reached. The consensus channel access mechanism based on local situation information provided by the application solves the problems of high packet loss rate and reduced network throughput in the existing channel access scheme.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular to a channel access method, apparatus, device, and storage medium. Background Technology

[0002] Mobile Ad Hoc Networks (MANETs) are multi-point, multi-hop networks sharing a wireless transmission medium. They consist of a group of mobile nodes that can access the network at any time, without relying on fixed communication network infrastructure. They are characterized by being decentralized, self-organizing, and having dynamically changing network topology. These characteristics lead to drawbacks such as frequent packet collisions, low throughput, high packet loss rate, and long end-to-end latency. These shortcomings can be mitigated by improving the MAC layer channel access protocol. The function of the channel access protocol is to control the occupation of the wireless medium by nodes' message transmissions and resolve the problem of wireless channel allocation among competing nodes. Therefore, the rationality of the MAC layer channel access protocol design directly affects the overall network performance.

[0003] Currently, the most commonly used MAC layer channel access protocols are contention-based protocols represented by CSMA / CA and allocation-based protocols represented by TDMA. Among them, the IEEE 802.11DCF mechanism, based on the CSMA / CA protocol, introduces the RTS / CTS mechanism to further address the hidden terminal problem. This mechanism exhibits good robustness in arbitrary network topologies and random traffic scenarios, but its flexible nature and backoff mechanism also bring significant drawbacks. As the number of nodes increases, mutual interference and transmission collisions increase, resulting in a significant waste of time in the backoff process, severely limiting system throughput and latency performance. TDMA protocols are time-synchronized MAC methods and can be divided into fixed-allocation and dynamic-allocation types. A typical fixed-allocation TDMA protocol involves multiple transmission frames, in which each node is allocated a time slot, thus eliminating the threat of node collisions. However, due to the decentralized nature of MANET networks and their latency requirements, fixed-allocation TDMA protocols perform poorly in large-scale network systems, exhibiting poor scalability and low channel utilization. Dynamic allocation TDMA protocols, such as the Five-Step Reservation Protocol (FPRP), dynamically allocate time slots through a five-step reservation process, overcoming the shortcomings of fixed allocation protocols. However, due to the high control overhead and implementation complexity of dynamic allocation TDMA protocols, node packet loss rates are relatively high, and network throughput is reduced.

[0004] Therefore, it is necessary to propose a suitable solution to address the problems of high node packet loss rate and reduced network throughput in the aforementioned channel access schemes. Summary of the Invention

[0005] The main objective of this application is to provide a channel access method, apparatus, device, and storage medium, which aims to solve the problems of high node packet loss rate and reduced network throughput in existing channel access schemes.

[0006] To achieve the above objectives, this application provides a channel access method, the channel access method comprising:

[0007] Before the start of the next decision cycle or when data packets need to be sent, obtain the situation information of the surrounding nodes of the target node;

[0008] The start time of the attempt to send the signal in the next decision cycle is determined based on the situation information of the surrounding nodes.

[0009] When the start time of the attempted transmission window is reached, the target node is controlled to access the channel.

[0010] Optionally, the step of determining the start time of the attempt to send window within the next decision cycle based on the surrounding node situation information includes:

[0011] Obtain node density parameters;

[0012] Based on the surrounding node situation information, the number of surrounding nodes with a data volume greater than zero is counted to obtain the current network density.

[0013] The start time of the attempt to send window in the next decision cycle is determined based on the current network density and the node density parameters.

[0014] Optionally, the step of determining the start time of the attempt sending window in the next decision period based on the current network density and the node density parameters includes:

[0015] Several decision-making cycles are obtained based on the target timeline;

[0016] The duration of the attempted transmission window is determined based on the decision cycle, the current network density, and the node density parameters.

[0017] A pseudo-random number interval is constructed based on the current network density and the node density parameters;

[0018] Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval;

[0019] The start time of the attempted transmission window is determined based on the start time of the next decision cycle, the pseudo-random integer, and the duration of the attempted transmission window.

[0020] Optionally, the step of determining the start time of the attempt sending window in the next decision period based on the current network density and the node density parameters includes:

[0021] Obtain the pre-set time frame length parameter;

[0022] The next decision cycle is determined based on the time frame length parameter, the current network density, and the node density parameter.

[0023] A pseudo-random number interval is constructed based on the current network density and the node density parameters;

[0024] Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval;

[0025] The start time of the attempted transmission window is determined based on the start time of the next decision cycle, the pseudo-random integer, and the time frame length parameter.

[0026] Optionally, the step of determining the start time of the attempt sending window in the next decision period based on the current network density and the node density parameters includes:

[0027] The probability of the start time of the attempted sending window in the next decision period is calculated based on the current network density and the node density parameters.

[0028] Construct a probability interval, and before the start of the next decision cycle or at the start of each time frame, select an arbitrary pseudo-random probability for each time frame from the uniform distribution of the probability interval.

[0029] Compare the magnitudes of the starting time probability and the pseudo-random probability;

[0030] If the pseudo-random probability is less than or equal to the starting time probability, then the starting time of the time frame corresponding to the pseudo-random probability is determined as the starting time of the attempted transmission window.

[0031] Optionally, after the step of determining the start time of the attempt to send window in the next decision cycle based on the surrounding node situation information, the method further includes:

[0032] The limited sending window is determined based on the attempted sending window in the next decision cycle;

[0033] When the start time of the restricted transmission window is reached, the target node is controlled to be in a restricted transmission state.

[0034] Optionally, after the step of controlling the target node to access the channel when the start time of the attempted transmission window is reached, the method further includes:

[0035] When the end time of the attempted sending window is reached, determine the current send / receive process status of the target node;

[0036] If the target node is in a random rollback state, the rollback count is frozen, the remaining rollback duration is saved, and the restricted sending window is entered.

[0037] If the target node is in the request sending state, monitor the response result and control the target node to execute the corresponding processing flow based on the response result;

[0038] If the target node is in a data transmission state, it will enter a restricted transmission window after the data transmission is completed.

[0039] If the target node is in another state, then the restricted sending window is entered, wherein the other state is a non-random rollback, non-request sending, and non-data sending state.

[0040] Optionally, before the step of obtaining the situational information of the surrounding nodes of the target node, the method further includes:

[0041] Using the target node as the maintenance center, the status information of surrounding nodes within a preset local status range of the target node is maintained, specifically including:

[0042] Receive situation information of surrounding nodes within a preset local situation range of the target node;

[0043] A local network situation information table is generated or updated based on the surrounding node situation information;

[0044] The steps for obtaining the situational information of the surrounding nodes of the target node include:

[0045] The local network situation information table is read, and the situation information of all surrounding nodes within the preset local situation range of the target node is extracted.

[0046] This application also proposes a channel access device, the channel access device comprising:

[0047] The acquisition module is used to acquire the situational information of the surrounding nodes of the target node before the start of the next decision cycle or when data packets need to be sent.

[0048] The determination module is used to determine the start time of the attempt to send window in the next decision cycle based on the surrounding node situation information;

[0049] The access module is used to control the target node to access the channel when the start time of the attempted transmission window is reached.

[0050] This application also proposes a channel access device, which includes a memory, a processor, and a channel access program stored in the memory and executable on the processor. When the channel access program is executed by the processor, it implements the steps of the channel access method described above.

[0051] This application also proposes a computer-readable storage medium storing a channel access program, which, when executed by a processor, implements the steps of the channel access method described above.

[0052] The channel access method, apparatus, device, and storage medium proposed in this application involve acquiring the surrounding node situation information of the target node before the start of the next decision cycle or when data packets need to be sent; determining the start time of the attempt transmission window within the next decision cycle based on the surrounding node situation information; and controlling the target node to access the channel when the start time of the attempt transmission window is reached. Based on this application's solution, by acquiring the surrounding node situation information perceived by the target node itself and determining the start time of the attempt transmission window within the next decision cycle based on the surrounding node situation information, decisions can be made based on the communication situation of the target node's surrounding environment. This allows for determining the start time of the attempt transmission window that the target node can actively access, avoiding the control information overhead caused by dynamic time slot allocation between nodes. By controlling the target node to actively access the channel and send and receive data packets when the start time of the attempt transmission window is reached, collisions between nodes can be effectively avoided, significantly reducing the node packet loss rate, improving network throughput, and resulting in a more significant performance improvement. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the functional modules of the device to which the channel access device belongs in this application;

[0054] Figure 2 This is a flowchart illustrating an exemplary embodiment of the channel access method of this application;

[0055] Figure 3 This is a flowchart illustrating another exemplary embodiment of the channel access method of this application;

[0056] Figure 4 This is a flowchart illustrating a third exemplary embodiment of the channel access method of this application;

[0057] Figure 5 This is a flowchart illustrating a fourth exemplary embodiment of the channel access method of this application;

[0058] Figure 6 This is a flowchart illustrating a fifth exemplary embodiment of the channel access method of this application;

[0059] Figure 7 This is a schematic diagram illustrating the decision cycle involved in an exemplary embodiment of the channel access method of this application;

[0060] Figure 8 This is a flowchart illustrating the sixth exemplary embodiment of the channel access method of this application;

[0061] Figure 9 This is a schematic diagram of a network topology as an example of the present invention;

[0062] Figure 10a This is a schematic diagram comparing the packet loss rate of the present invention with that of the DCF mechanism;

[0063] Figure 10b This is a schematic diagram comparing the network saturation throughput of the present invention with that of the DCF mechanism;

[0064] Figure 11 This is a schematic diagram of the node network movement trajectory topology as an example of the present invention;

[0065] Figure 12a This is a schematic diagram comparing the packet loss rate of the present invention with that of the DCF mechanism in a mobile scenario;

[0066] Figure 12b This is a schematic diagram comparing the network saturation throughput of the present invention and the DCF mechanism in a mobile scenario;

[0067] Figure 13a This is a schematic diagram comparing the packet loss rate of the present invention and the DCF mechanism under conditions of unsaturated business load.

[0068] Figure 13b This is a schematic diagram comparing the network throughput of the present invention and the DCF mechanism under conditions of unsaturated service load.

[0069] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0070] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0071] The main solution of this application embodiment is as follows: before the start of the next decision cycle or when data packets need to be sent, obtain the situational information of the surrounding nodes of the target node; determine the start time of the attempt to send window in the next decision cycle based on the situational information of the surrounding nodes; when the start time of the attempt to send window is reached, control the target node to access the channel. Based on the solution of this application, by obtaining the situational information of the surrounding nodes perceived by the target node itself, and determining the start time of the attempt to send window in the next decision cycle based on the situational information of the surrounding nodes, decisions can be made based on the communication situation of the target node's surrounding environment, determining the start time of the attempt to send window that the target node can actively access, avoiding the control information overhead caused by dynamic time slot allocation between nodes; by controlling the target node to actively access the channel at the start time of the attempt to send window to send and receive data packets, collisions between nodes can be effectively avoided, greatly reducing the node packet loss rate, improving network throughput, and making the performance improvement more significant.

[0072] Specifically, refer to Figure 1 , Figure 1 This is a functional module diagram of the device to which the channel access device belongs in this application belongs. The channel access device can be an independent device capable of data acquisition and channel access, and can be implemented on the device in hardware or software form. The device can be a smart terminal with data processing capabilities, such as a mobile phone or computer, or a fixed device or server with data processing capabilities.

[0073] In this embodiment, the device to which the channel access device belongs includes at least an output module 110, a processor 120, a memory 130, and a communication module 140.

[0074] The memory 130 stores the operating system and channel access program. The channel access device can store information such as the surrounding node situation information of the target node, the start time of the attempt transmission window in the next decision cycle determined based on the surrounding node situation information, and data packets to be sent and received in the memory 130. The output module 110 can be a display screen, etc. The communication module 140 can include a WIFI module, a mobile communication module, and a Bluetooth module, etc., and communicates with external devices or servers through the communication module 140.

[0075] When the channel access program in memory 130 is executed by the processor, it performs the following steps:

[0076] Before the start of the next decision cycle or when data packets need to be sent, obtain the situation information of the surrounding nodes of the target node;

[0077] The start time of the attempt to send the signal in the next decision cycle is determined based on the situation information of the surrounding nodes.

[0078] When the start time of the attempted transmission window is reached, the target node is controlled to access the channel.

[0079] Furthermore, when the channel access program in memory 130 is executed by the processor, it also performs the following steps:

[0080] Obtain node density parameters;

[0081] Based on the surrounding node situation information, the number of surrounding nodes with a data volume greater than zero is counted to obtain the current network density.

[0082] The start time of the attempt to send window in the next decision cycle is determined based on the current network density and the node density parameters.

[0083] Furthermore, when the channel access program in memory 130 is executed by the processor, it also performs the following steps:

[0084] Several decision-making cycles are obtained based on the target timeline;

[0085] The duration of the attempted transmission window is determined based on the decision cycle, the current network density, and the node density parameters.

[0086] A pseudo-random number interval is constructed based on the current network density and the node density parameters;

[0087] Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval;

[0088] The start time of the attempted transmission window is determined based on the start time of the next decision cycle, the pseudo-random integer, and the duration of the attempted transmission window.

[0089] Furthermore, when the channel access program in memory 130 is executed by the processor, it also performs the following steps:

[0090] Obtain the pre-set time frame length parameter;

[0091] The next decision cycle is determined based on the time frame length parameter, the current network density, and the node density parameter.

[0092] A pseudo-random number interval is constructed based on the current network density and the node density parameters;

[0093] Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval;

[0094] The start time of the attempted transmission window is determined based on the start time of the next decision cycle, the pseudo-random integer, and the time frame length parameter.

[0095] Furthermore, when the channel access program in memory 130 is executed by the processor, it also performs the following steps:

[0096] The probability of the start time of the attempted sending window in the next decision period is calculated based on the current network density and the node density parameters.

[0097] Construct a probability interval, and before the start of the next decision cycle or at the start of each time frame, select an arbitrary pseudo-random probability for each time frame from the uniform distribution of the probability interval.

[0098] Compare the magnitudes of the starting time probability and the pseudo-random probability;

[0099] If the pseudo-random probability is less than or equal to the starting time probability, then the starting time of the time frame corresponding to the pseudo-random probability is determined as the starting time of the attempted transmission window.

[0100] Furthermore, when the channel access program in memory 130 is executed by the processor, it also performs the following steps:

[0101] The limited sending window is determined based on the attempted sending window in the next decision cycle;

[0102] When the start time of the restricted transmission window is reached, the target node is controlled to be in a restricted transmission state.

[0103] Furthermore, when the channel access program in memory 130 is executed by the processor, it also performs the following steps:

[0104] When the end time of the attempted sending window is reached, determine the current send / receive process status of the target node;

[0105] If the target node is in a random rollback state, the rollback count is frozen, the remaining rollback duration is saved, and the restricted sending window is entered.

[0106] If the target node is in the request sending state, monitor the response result and control the target node to execute the corresponding processing flow based on the response result;

[0107] If the target node is in a data transmission state, it will enter a restricted transmission window after the data transmission is completed.

[0108] If the target node is in another state, then the restricted sending window is entered, wherein the other state is a non-random rollback, non-request sending, and non-data sending state.

[0109] Furthermore, when the channel access program in memory 130 is executed by the processor, it also performs the following steps:

[0110] Using the target node as the maintenance center, the status information of surrounding nodes within a preset local status range of the target node is maintained, specifically including:

[0111] Receive situation information of surrounding nodes within a preset local situation range of the target node;

[0112] A local network situation information table is generated or updated based on the surrounding node situation information;

[0113] The local network situation information table is read, and the situation information of all surrounding nodes within the preset local situation range of the target node is extracted.

[0114] This embodiment, through the above-described scheme, specifically acquires the situational information of surrounding nodes of the target node before the start of the next decision cycle or when data packets need to be sent; determines the start time of the attempt transmission window within the next decision cycle based on the surrounding node situational information; and controls the target node to access the channel when the start time of the attempt transmission window is reached. Based on this application's scheme, by acquiring the surrounding node situational information perceived by the target node itself, and determining the start time of the attempt transmission window within the next decision cycle based on the surrounding node situational information, decisions can be made based on the communication situation of the target node's surrounding environment. This allows for determining the start time of the attempt transmission window that the target node can actively access, avoiding the control information overhead caused by dynamic time slot allocation between nodes. By controlling the target node to actively access the channel and send and receive data packets when the start time of the attempt transmission window is reached, collisions between nodes can be effectively avoided, significantly reducing the node packet loss rate, improving network throughput, and resulting in a more significant performance improvement.

[0115] Based on, but not limited to, the above-described device architecture, this application proposes method embodiments.

[0116] This application proposes a consensus channel access method based on local situational information for MAC layer channel access protocols in wireless ad hoc networks. This method draws on the characteristics of TDMA and CSMA / CA protocols, innovatively incorporating a consensus access concept to fuse the two protocols. This not only avoids the control information overhead caused by dynamic time slots between nodes, but also solves the performance degradation problem caused by excessive collision rates in dense networks. Compared to IEEE 802.11DCF technology, this method significantly reduces node packet loss rate and improves network throughput, especially in large-scale dense network scenarios where the performance improvement is even more pronounced.

[0117] In this embodiment, the execution entity of the consensus channel access method based on local situational information can be a channel access device, a channel access equipment, or a server. This embodiment takes a channel access device as an example. The channel access device can be integrated into a terminal device, computer, or other device with data processing capabilities.

[0118] After the target node is powered on via the channel access device, the local situation maintenance module deployed on it processes the situation information broadcast by other nodes, i.e., the situation information of surrounding nodes. At the same time, the local situation maintenance module is responsible for periodically triggering the target node to broadcast its own situation information during the network operation.

[0119] Reference Figure 2 , Figure 2 This is a flowchart illustrating an exemplary embodiment of the channel access method of this application. The channel access method includes:

[0120] Step S10: Before the start of the next decision cycle or when data packets need to be sent, obtain the situation information of the surrounding nodes of the target node.

[0121] Specifically, the entire target timeline is pre-divided into multiple decision cycles. Before the start of the next decision cycle, or when the target node needs to send data packets, the situational information of the surrounding nodes of the target node is acquired. This situational information can be the situational information broadcast by the target node and other nodes outside the target node, which is maintained in real-time by the local situational maintenance module of the channel access device. This situational information may include, but is not limited to, network topology, network node identifiers, the amount of data to be sent by the node, the activity level of surrounding nodes, and data transmission frequency.

[0122] In this embodiment, the local situation maintenance module can set the local situation range according to actual needs. For example, when the local situation range N≥2 is set, the local situation maintenance module of the channel access device maintains the situation information of surrounding nodes N hops (greater than or equal to two hops) centered on the target node in real time.

[0123] This embodiment can analyze and understand the communication status of the surrounding nodes of the target node by obtaining the situation information of the surrounding nodes.

[0124] Step S20: Determine the start time of the attempt to send window in the next decision cycle based on the surrounding node situation information.

[0125] Specifically, based on the acquired situational information of surrounding nodes, the time period during which the target node can actively access the channel and its starting time are determined within the next decision cycle, which is also the starting time of the attempt to send in the next decision cycle.

[0126] More specifically, based on the acquired situational information of surrounding nodes, information such as network node identifiers and the amount of data to be transmitted by the nodes is statistically analyzed. Based on the statistical results of the surrounding node situational information, the time period during which the target node can actively access the channel in the next decision cycle is calculated. During this time period, the target node continuously attempts to transmit data packets. When the transmission conditions are met, the target node is controlled to occupy the channel and initiate the data packet transmission process. In this embodiment, the time period during which the target node can actively access the channel is defined as the attempt transmission window, and the node state during this time period is defined as the attempt transmission state. Then, based on the calculated time period during which the target node can actively access the channel in the next decision cycle, i.e., the attempt transmission window in the next decision cycle, the start time of the attempt transmission window is determined.

[0127] This embodiment determines the time period during which the target node can actively access the channel in the next decision cycle based on the situational information of surrounding nodes perceived by the target node itself, according to certain rules. This results in a shorter time for nodes in densely transmitting areas to actively access the channel and a longer time for nodes in sparsely transmitting areas to actively access the channel, thereby avoiding collisions between nodes and improving network performance.

[0128] Step S30: When the start time of the attempted transmission window is reached, control the target node to access the channel.

[0129] Specifically, when the start time of the attempt to send in the next decision cycle is reached, the target node is controlled to access the channel and send and receive data packets.

[0130] More specifically, when the target node accesses the channel at the beginning of the transmission window, it will determine the channel's idle / busy status through carrier sensing and use the IEEE 802.11DCF working mechanism to send data packets and receive responses.

[0131] This embodiment, through the above-described scheme, specifically acquires the situational information of surrounding nodes of the target node before the start of the next decision cycle or when data packets need to be sent; determines the start time of the attempt transmission window within the next decision cycle based on the surrounding node situational information; and controls the target node to access the channel when the start time of the attempt transmission window is reached. Based on this embodiment, by acquiring the surrounding node situational information perceived by the target node itself, and determining the start time of the attempt transmission window within the next decision cycle based on the surrounding node situational information, decisions can be made based on the communication situation of the target node's surrounding environment. This allows for determining the start time of the attempt transmission window that the target node can actively access, avoiding the control information overhead caused by dynamic time slot allocation between nodes. By controlling the target node to actively access the channel and send and receive data packets when the start time of the attempt transmission window is reached, collisions between nodes can be effectively avoided, significantly reducing the node packet loss rate, improving network throughput, and resulting in a more significant performance improvement.

[0132] Furthermore, as an example, refer to Figure 3 , Figure 3 This is a flowchart illustrating another exemplary embodiment of the channel access method of this application. After determining the start time of the attempt transmission window within the next decision period based on the surrounding node situation information in step S20 above, the method may further include:

[0133] Step S40: Determine the limited sending window based on the attempted sending window in the next decision cycle.

[0134] Specifically, after determining the attempt transmission window for the next decision period, the time period occupied by the non-attempt transmission window within the next decision period is determined as the restricted transmission window based on the overall duration of the next decision period. Within this restricted transmission window, the target node, as the called party, is in a restricted transmission state. In this restricted transmission state, the target node does not need to listen for physical carriers and will not attempt to send data packets. However, the target node in this restricted transmission state will still passively send response frames, such as CTS and ACK.

[0135] Step S50: When the start time of the restricted transmission window is reached, control the target node to be in the restricted transmission state.

[0136] Specifically, when the start time of the restricted transmission window in the next decision cycle is reached, the target node is controlled to be in a restricted transmission state. That is, the target node in the restricted transmission state, as the called party, retains the passive receiving or response function. In this state, the target node will still passively send response frames, but it does not need to listen for physical carriers and will not attempt to send data packets.

[0137] In this embodiment, under restricted transmission mode, the target node does not need to perform physical carrier sensing or attempt to send data packets, thereby reducing energy consumption. This is especially important for energy-constrained nodes such as mobile devices. By controlling the target node to be in restricted transmission mode within the restricted transmission window, the target node only passively receives or responds and does not actively send data packets, avoiding collisions between nodes and thus improving network capacity.

[0138] Furthermore, referring to Figure 4 , Figure 4 This is a flowchart illustrating a third exemplary embodiment of the channel access method of this application. Based on the embodiments shown above, in this embodiment, step S20, determining the start time of the attempt transmission window within the next decision period based on the surrounding node situation information, may include:

[0139] Step S21: Obtain the node density parameters.

[0140] Specifically, node density parameters are obtained through a channel access device, whereby the node density parameter represents the overall density of nodes in the network. This node density parameter can be a pre-set, fixed overall network node density parameter, or it can be a dynamically changing overall network node density parameter according to a specific pattern. The range of this node density parameter is at least greater than zero.

[0141] Step S22: Based on the surrounding node situation information, count the number of surrounding nodes with a data volume greater than zero to obtain the current network density.

[0142] Specifically, based on the obtained situational information of surrounding nodes, the number of nodes in the surrounding nodes of the target node with a data volume greater than zero is counted, and the current network density is determined based on the counted number of surrounding nodes with a data volume greater than zero.

[0143] Step S23: Determine the start time of the attempt to send window in the next decision cycle based on the current network density and the node density parameters.

[0144] Specifically, the start time of the attempt to send data in the next decision cycle is determined based on the statistical current network density and the obtained node density parameters.

[0145] In one embodiment, the method for determining the start time of the attempted transmission window in the next decision cycle based on the current network density and node density parameters may include: pre-setting the cycle duration and start time of the next decision cycle; determining the attempted transmission window duration in the next decision cycle based on the current network density and node density parameters according to the method for determining the attempted transmission window duration; and then determining the start time of the attempted transmission window in the next decision cycle based on the preset cycle duration and start time of the next decision cycle and the attempted transmission window duration in the next decision cycle. Wherein, the cycle duration of the next decision cycle is greater than or equal to the attempted transmission window duration in the next decision cycle.

[0146] In another embodiment, the method for determining the start time of the attempt to send window in the next decision period based on the current network density and node density parameters may further include: presetting the attempt to send window duration; determining the next decision period based on the current network density and node density parameters according to the method for determining the decision period; and then determining the start time of the attempt to send window in the next decision period based on the preset attempt to send window duration and the period duration and start time of the next decision period.

[0147] In other embodiments, the method for determining the start time of the attempt to send window in the next decision period based on the current network density and node density parameters may further include: determining the next decision period and the duration of the attempt to send window based on the current network density and node density parameters, and determining the start time of the attempt to send window in the next decision period based on the duration of the attempt to send window, the duration of the next decision period, and its start time.

[0148] In another embodiment, the method for determining the start time of the attempted transmission window in the next decision period based on the current network density and node density parameters may further include: determining the probability of the start time of the attempted transmission window based on the current network density and node density parameters, and determining the start time of the attempted transmission window in the next decision period based on the probability of the start time. The number of attempted transmission windows in the next decision period may be determined by the probability of the start time, and the total duration of the attempted transmission window may also be determined by the probability of the start time.

[0149] This embodiment, through the above scheme, dynamically determines the start time of the attempt to send in the next decision cycle based on the current network density and node density parameters. It can adjust the channel access time according to the current network communication situation to avoid collisions between nodes and control information overhead, thereby improving network performance and efficiency.

[0150] Furthermore, referring to Figure 5 , Figure 5 This is a flowchart illustrating a fourth exemplary embodiment of the channel access method of this application. Based on the above... Figure 4 In the embodiment shown, step S23 above, determining the start time of the attempt to send window in the next decision period based on the current network density and the node density parameters, may include:

[0151] Step S2310: Divide the target time axis into several decision cycles;

[0152] Step S2311: Determine the duration of the attempted transmission window based on the decision cycle, the current network density, and the node density parameters;

[0153] Specifically, the target timeline is obtained and divided into multiple decision periods, yielding the duration and start time of each period. The duration of each decision period can be a fixed, uniform duration, or it can be a different duration allocated to different decision periods. Based on each decision period, the determined current network density, and node density parameters, the attempted transmission window duration for the next decision period is determined.

[0154] For example, the entire target timeline is divided into multiple decision cycles of equal length, with the cycle length being a uniform fixed parameter DecisionCycle for all nodes in the network. The situational information of surrounding nodes of the target node is obtained, and the number of nodes with a data volume greater than zero (SendNodeNum) is statistically calculated based on this information to characterize the current network density. The node density parameter SubNodeNum > 0 is obtained, and the attempt-to-send window duration (SendWindow) for the next decision cycle is determined according to the method for determining the attempt-to-send window duration, based on the decision cycle, the current network density, and the node density parameter. The method for determining the attempt-to-send window duration can be shown in Formula 1 below:

[0155]

[0156] Here, SendWindow is the duration of the attempt to send data in the next decision cycle, DecisionCycle is the duration of the next decision cycle, SendNodeNum is the current network density, and SubNodeNum is a parameter representing the node density level. This is the floor operator.

[0157] Step S2312: Construct a pseudo-random number interval based on the current network density and the node density parameters;

[0158] Step S2313: Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval;

[0159] Step S2314: Determine the start time of the attempted transmission window based on the start time of the next decision cycle, the pseudo-random integer, and the duration of the attempted transmission window.

[0160] Specifically, a pseudo-random number interval is constructed based on the determined current network density and node density parameters. An arbitrary pseudo-random integer is selected from the uniform distribution of the constructed pseudo-random number interval. The start time of the attempt-to-send window in the next decision period is determined based on the start time of the next decision period, the selected pseudo-random integer, and the duration of the attempt-to-send window within the next decision period.

[0161] For example, the method for determining the start time of the attempted sending window (SendWindowStart) in the next decision cycle is as follows:

[0162] A pseudo-random number interval is constructed based on the determined parameters of current network density and node density. Select a pseudo-random integer mw from the uniform distribution in the interval, and start the calculation from the beginning of the next decision period. After mw×SendWindow time, where SendWindow is the duration of the attempt to send, the target node enters the attempt to send window, that is, the start time of the attempt to send window SendWindowStart is the time after mw×SendWindow time from the beginning of the next decision period.

[0163] This embodiment adopts a fixed and uniform decision cycle duration. Within each decision cycle, the duration of the attempt to send is dynamically adjusted according to the current network density and node density parameters. In other words, the duration of the attempt to send changes with the density characterization, thereby achieving flexible control over the duration of the attempt to send and improving channel utilization and network performance.

[0164] Furthermore, referring to Figure 6 , Figure 6 This is a flowchart illustrating the fifth exemplary embodiment of the channel access method of this application, based on the above. Figure 4 In the embodiment shown, step S23 above, determining the start time of the attempt to send window in the next decision period based on the current network density and the node density parameters, may include:

[0165] Step S2320: Obtain the pre-set time frame length parameter;

[0166] Step S2321: Determine the next decision cycle based on the time frame length parameter, the current network density, and the node density parameter.

[0167] In this embodiment, each decision cycle may consist of multiple time frames. A pre-set time frame length parameter is obtained, wherein this time frame length parameter is a fixed time frame length parameter uniform across all nodes in the network. The next decision cycle is determined based on the pre-set time frame length parameter, the current network density, and the node density parameter.

[0168] In this embodiment, the time frame within the decision period that allows active channel access is defined as the attempt transmission window, and the node state during that time frame is defined as the attempt transmission state. Therefore, the duration of the attempt transmission window in this embodiment can be set to the length of the time frame that allows active channel access.

[0169] For example, such as Figure 7 As shown, the length of each time frame is set to a unified fixed parameter Slot for all nodes in the network, and the duration of the attempt to send is one time frame. First, the situational information of the surrounding nodes of the target node is obtained. Based on this information, the number of nodes with a data volume greater than zero (SendNodeNum) is calculated, representing the current network density. The node density parameter SubNodeNum > 0 is obtained. Assuming the decision cycle consists of M time frames, all time frames are numbered sequentially as {0, 1, ..., M-1}. The m-th time frame within the decision cycle is the attempt to send time frame, and the other time frames are defined as restricted sending time frames. These restricted sending time frames form a restricted sending window, and the node state within this window is defined as the restricted sending state. Following the method for determining the decision cycle, the next decision cycle (DecisionCycle) is determined based on the time frame length parameter Slot, the current network density, and the node density parameter. The method for confirming the next decision cycle can be referenced in formulas 2 and 3 below:

[0170]

[0171] DecisionCycle=M×Slot (3)

[0172] Where M represents the number of time frames occupied by the next decision cycle, DecisionCycle represents the next decision cycle, SendNodeNum represents the current network density, and SubNodeNum represents the node density parameter. This is the floor operator, and Slot is the time frame length parameter.

[0173] Step S2322: Construct a pseudo-random number interval based on the current network density and the node density parameters;

[0174] Step S2323: Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval;

[0175] Step S2324: Determine the start time of the attempted transmission window based on the start time of the next decision cycle, the pseudo-random integer, and the time frame length parameter;

[0176] Specifically, a pseudo-random number interval is constructed based on the determined current network density and node density parameters. An arbitrary pseudo-random integer is selected from the uniform distribution of the constructed pseudo-random number interval. The start time of the attempted transmission window within the next decision period is determined based on the start time of the next decision period, the selected pseudo-random integer, and the time frame length parameter.

[0177] For example, the method for determining the start time of the attempted sending window (SendWindowStart) in the next decision cycle is as follows:

[0178] A pseudo-random number interval is constructed based on the determined parameters of current network density and node density. A pseudo-random integer mw is selected from the uniform distribution in the interval. The calculation starts from the beginning of the next decision period. After mw×Slot time, where Slot is the time frame length parameter, that is, the duration of the attempt to send window, the target node enters the attempt to send window. That is, the start time of the attempt to send window SendWindowStart is the time after mw×Slot time from the beginning of the next decision period.

[0179] This embodiment achieves flexible control of the decision period duration based on the actual network conditions by keeping the transmission window duration constant within each decision period, while dynamically adjusting the decision period duration according to parameters such as frame length, current network density, and node density. This improves channel utilization and network performance.

[0180] Furthermore, referring to Figure 8 , Figure 8 This is a flowchart illustrating the sixth exemplary embodiment of the channel access method of this application, based on the above. Figure 4 In the embodiment shown, step S23 above, determining the start time of the attempt to send window in the next decision period based on the current network density and the node density parameters, may include:

[0181] Step S2330: Calculate the probability of the start time of the attempted sending window in the next decision period based on the current network density and the node density parameters.

[0182] Specifically, based on the statistical current network density and preset node density parameters, the probability of the start time of the attempted transmission window in the next decision period is calculated. This start time probability refers to the probability that the start time of the attempted transmission window occurs at the start time of any time frame in the next decision period.

[0183] Step S2331: Construct a probability interval. Before the start of the next decision cycle or at the beginning of each time frame, select an arbitrary pseudo-random probability for each time frame from the uniform distribution of the probability interval.

[0184] Step S2332: Compare the starting time probability and the pseudo-random probability.

[0185] Step S2333: If the pseudo-random probability is less than or equal to the starting time probability, then the starting time of the time frame corresponding to the pseudo-random probability is determined as the starting time of the attempted transmission window.

[0186] Specifically, to determine whether a given time frame in the next decision cycle is the starting time frame of the attempted transmission window, a probability interval of 0-1 is constructed. Before the start of the next decision cycle, or at the start time of each time frame within the next decision cycle, an arbitrary pseudo-random probability is selected from the uniform distribution of the constructed probability interval. Then, the calculated probability of the starting time of the attempted transmission window in the next decision cycle is compared with the selected pseudo-random probability. If the pseudo-random probability is less than or equal to the probability of the starting time of the attempted transmission window in the next decision cycle, the time frame corresponding to the current pseudo-random probability is determined as the starting time frame of the attempted transmission window, and the start time of the time frame corresponding to this pseudo-random probability is determined as the start time of the attempted transmission window in the next decision cycle.

[0187] It should be noted that, in this embodiment, each decision cycle duration consists of several time frames. In the next decision cycle duration, there are several time frames that have the probability of being defined as attempt transmission windows. These time frames defined as attempt transmission windows may be connected together, or they may be scattered across various time frames in the next decision cycle. Therefore, the method of this embodiment makes the total duration of the attempt transmission window and its relative start time probabilistically determined.

[0188] For example, based on the current network density and node density parameters, the probability P0 of the starting time of the attempted sending window in the next decision period is calculated, wherein the method for calculating the starting time probability can refer to the following formula 4:

[0189]

[0190] Where P0 is the probability of attempting to send at the start time of the next decision period, SendNodeNum is the current network density, and SubNodeNum is the node density parameter. This is the floor operator.

[0191] Each decision cycle consists of multiple time frames. To determine whether each time frame in the next decision cycle is a potential transmission window, a probability interval [0, 1] is first constructed. An arbitrary pseudo-random probability p is selected from the uniform distribution within this interval. The magnitude of the probability P0 of the starting time of the potential transmission window in the next decision cycle is compared with the pseudo-random probability p. If p ≤ P0, the time frame corresponding to the current pseudo-random probability is considered the starting time frame of the potential transmission window, and the starting time of this pseudo-random probability time frame is determined as the starting time of the potential transmission window in the next decision cycle. Otherwise, the time frame corresponding to the current pseudo-random probability is considered a restricted transmission window.

[0192] In this example, the pseudo-random probability p can be randomly selected for each time frame within the decision period at the start of the next decision period; or it can be randomly selected from the probability interval at the start of each time frame within the decision period.

[0193] Furthermore, based on the embodiments shown above, in this embodiment, after controlling the target node to access the channel when the start time of the attempted transmission window is reached in step S30, it may further include: when the end time of the attempted transmission window is reached, determining the current transmit / receive process status of the target node.

[0194] Specifically, when the end time of the attempt to send window in the next decision cycle is reached, the current send / receive process status of the target node is determined. This send / receive process status may include, but is not limited to, random rollback status, request to send status, and data sending status.

[0195] Optionally, if the target node is in a random rollback state, the rollback count is frozen, the remaining rollback duration is saved, and the restricted sending window is entered.

[0196] Specifically, if the target node is in a random rollback state when the end of the attempt to send window is reached, the rollback count is frozen, the remaining rollback duration is saved, and the restricted sending window begins to be entered. Furthermore, if the target node is in a random rollback state when the current attempt to send window ends, a new random rollback is initiated the next time the attempt to send window is entered, allowing the frozen rollback count to continue.

[0197] Optionally, if the target node is in a request sending state, the response result is monitored, and the target node is controlled to execute the corresponding processing flow based on the response result.

[0198] Specifically, if the target node is in the request RTS send state when the end time of the attempt to send window is reached, the response result after the request is sent is monitored, and the target node is controlled to execute the corresponding processing flow based on the response result. For example, if a response CTS frame (Clear to Send frame) is received, indicating confirmation that data packets can be received, the target node is controlled to continue to complete the subsequent process, such as sending data DATA, waiting for acknowledgment ACK, etc., based on the received response result; if no response CTS frame is received within the predetermined time, the current response result is empty. At this time, the target node is controlled to enter the restricted send window based on the timeout failure result.

[0199] Optionally, if the target node is in a data transmission state, it will enter a restricted transmission window after the data transmission is completed.

[0200] Specifically, if the target node is in the data sending state when the end time of the attempt to send window is reached, then continue to send data and, after the data sending is completed, control the target node to enter the restricted sending window.

[0201] Optionally, if the target node is in another state, then a restricted sending window is entered, wherein the other state is a non-random rollback, non-request sending, and non-data sending state.

[0202] Specifically, if the target node is in any of the other states when the end of the attempt to send window is reached, i.e., in a non-random backoff, non-request to send, and non-data sending state, then the target node is controlled to enter the restricted sending window.

[0203] For example, at a certain moment before the end of the current decision cycle or when the target node needs to send a data packet, the situational information of the surrounding nodes of the target node is obtained. Each decision cycle is divided according to a set target timeline, and each divided decision cycle consists of multiple time frame slots. Based on the obtained situational information of the surrounding nodes, the duration of the attempt to send a data packet (SendWindow) and the start time of the attempt to send a data packet (SendWindowStart) for the next decision cycle are determined. At the beginning of the next decision cycle, the target node enters a restricted sending state, starts a waiting timer (TW), and sets the timer duration to mw × SendWindow, from the start time of the next decision cycle to the start time of the attempt to send a data packet, where mw is a pseudo-random integer.

[0204] In restricted transmission mode, the physical layer can receive signals but does not actively perform carrier sensing. The data link layer (MAC layer) can only execute all procedures for the called party in the IEEE 802.11 DCF scheme. For example, when the MAC layer receives an RTS frame, if the destination address is the target node itself, it determines whether to send a response CTS frame based on the Network Allocation Vector (NAV); when the MAC layer receives a DATA frame, if the destination address is the target node itself, it determines whether to send a response ACK frame based on the NAV; in other cases, such as receiving RTS, CTS, DATA, or ACK frames with destination addresses of other nodes, it updates the NAV based on the "duration" field in the frame.

[0205] The target node is controlled to access the channel and enter the attempt-to-transmit state when the timer TW times out, i.e., when the start time mw×SendWindow of the next decision cycle's attempt-to-transmit window is reached. Simultaneously, the wait timer TW is restarted, and its duration is set to the attempt-to-transmit window duration SendWindow. In this attempt-to-transmit state, the physical layer requires carrier sensing and signal reception; the MAC layer processing flow is the same as the IEEE 802.11DCF scheme.

[0206] Until the timer TW times out again, which is the end of the attempt to send window, the target node may be in different states of the data packet sending and receiving process. Determine the current sending and receiving process state of the target node.

[0207] If the current target node is in a random rollback state, the rollback count is frozen, the remaining rollback duration is saved, and the node begins entering the restricted sending window. Furthermore, if the target node is in a random rollback state when the current sending window ends, a new random rollback is initiated the next time the node enters the sending window, allowing the frozen rollback count to continue.

[0208] If the current target node is in the request RTS send state, the response result after the request is sent is monitored, and the target node is controlled to execute the corresponding processing flow based on the response result. For example, if a response CTS frame (Clear to Send frame) is received, indicating confirmation that data packets can be received, the target node is controlled to continue to complete the subsequent process, such as sending data DATA and waiting for acknowledgment ACK, based on the received response result; if no response CTS frame is received within the predetermined time, the current response result is empty. At this time, the target node is controlled to enter the restricted sending window based on the timeout failure result.

[0209] If the target node is currently in the data sending state, continue sending data and, after the data sending is completed, control the target node to enter the restricted sending window.

[0210] If the current target node is in any of the other states, i.e., in a non-random rollback, non-request to send, and non-data sending state, then control the target node to immediately enter the restricted sending window.

[0211] Then, until the end of the current decision cycle, if the target node still has data to send, the attempt window and its start time for the next decision cycle will be recalculated.

[0212] This embodiment of the solution performs corresponding processing based on the current send / receive process status of the target node and enters a restricted sending window. It can flexibly control the sending behavior according to the actual status of the target node, thereby improving network performance and efficiency.

[0213] Furthermore, based on the embodiments described above, in this embodiment, before obtaining the situational information of the surrounding nodes of the target node in step S10, the following may also be included:

[0214] Step S01: Using the target node as a maintenance center, maintain the situation information of surrounding nodes within a preset local situation range of the target node.

[0215] Specifically, before acquiring the situational information of the surrounding nodes of the target node, the channel access device, after the target node is powered on, uses its deployed local situational maintenance module to maintain the situational information of the surrounding nodes within the preset local situational range of the target node, with the target node as the maintenance center.

[0216] For example, assuming the local situation range N≥2, the local situation maintenance module of the channel access device maintains the situation information of surrounding nodes with N hops (greater than or equal to two hops) centered on the target node.

[0217] Furthermore, step S01 above may specifically include:

[0218] Step S011: Receive the situation information of surrounding nodes within the preset local situation range of the target node;

[0219] Step S012: Generate or update the local network situation information table based on the surrounding node situation information.

[0220] More specifically, the deployed local situation maintenance module receives situation information of surrounding nodes within a preset local situation range for the target node, wherein the preset local situation range is at least two hops or greater. A local network situation information table is generated or updated based on the received surrounding node situation information.

[0221] Furthermore, step S10 above may include:

[0222] Step S11: Read the local network situation information table and extract the situation information of all surrounding nodes within the preset local situation range of the target node.

[0223] Specifically, a pre-generated or updated local situation information table is read, and situation information of all surrounding nodes within the preset local situation range of the target node is extracted from it. The surrounding node situation information is used to count the number of surrounding nodes with a data volume greater than zero, thereby characterizing the current network density.

[0224] Then, based on the situation information of surrounding nodes and the current network density obtained from statistics, the start time of the attempt to send data in the next decision cycle is determined; when the start time of the attempt to send data is reached, the target node is controlled to access the channel and send and receive data packets.

[0225] This embodiment, through the above-described scheme, maintains the situational information of surrounding nodes within the local situational range perceived by the target node itself. Based on the situational information of surrounding nodes, it determines the start time of the attempted transmission window in the next decision cycle. It can make decisions based on the communication situation of the target node's surrounding environment, determining the start time of the attempted transmission window that the target node can actively access, thus avoiding the control information overhead caused by dynamic time slot allocation between nodes. By controlling the target node to actively access the channel and send and receive data packets at the start time of the attempted transmission window, collisions between nodes can be effectively avoided, greatly reducing the node packet loss rate, improving network throughput, and making the performance improvement more significant.

[0226] For example, refer to Figure 9 , Figure 9 This is a network topology diagram illustrating an example of the present invention. The example employs a channel access method based on local situational information to construct a simulation environment for a large-scale network. The simulation parameters are shown in Table 1 below:

[0227] parameter IEEE 802.11 DCF mechanism Network access mechanism Topological region 500m×500m 500m×500m Signal transmission radius (m) 300 300 Data packet length (Bytes) 1500 1500 CWMAX 2 5 ~2 10 ]] <![CDATA[2 5 ~2 10 ]]> Transmission rate (bps) 3.25M 3.25M Number of retransmissions 4 4 SubNodeNumber \ 15 DecisionCycle \ 100ms

[0228] Table 1: IEEE 802.11DCF and Access Mechanism Parameter Configuration

[0229] Under the above simulation parameters, the network node locations are randomly distributed, and each node is in a saturated transmission state. Figure 9 This example demonstrates a network topology with 100 nodes within a 500m × 500m area. Compared to the DCF mechanism in the IEEE 802.11n standard, the advantages of this example's channel access method based on local situational information are as follows:

[0230] (1) Compare packet loss rate performance, such as Figure 10aAs shown in the simulation results, the access mechanism proposed in this example significantly reduces the packet loss rate of data transmitted at the MAC layer. In the simulation experiment, compared with DCF technology, the access mechanism in this example reduces the packet loss rate from 39.3% to 19.0%. The reduction in packet loss rate not only improves the energy utilization of nodes but also reduces the probability of retransmission of end-to-end data at the upper layer, thereby reducing the average end-to-end latency of the network.

[0231] (2) Compare the network saturation throughput performance, such as Figure 10b As shown in the simulation results, under large-scale dense networking conditions, the access mechanism proposed in this example significantly improves the network saturation throughput. In the simulation experiment, compared with DCF technology, the access mechanism in this example improves the network saturation throughput by 29.7%.

[0232] For example, refer to Figure 11 , Figure 11 This is a schematic diagram of the node network movement trajectory topology as an example of the present invention. A node movement scenario is constructed in this example, and a node movement model is added based on the above example. The parameters of the node movement model are shown in Table 2 below:

[0233] parameter value Motion Model Random waypoint model movement range 1000m×1000m Movement speed (m / s) Uniform(10,20) randomly selects Move start time (s) 40 travel time 120s

[0234] Table 2: Parameters of Node Mobility Model

[0235] The simulation results obtained based on this node movement model are as follows: Figure 12a and Figure 12b As shown, curve ① represents the performance of DCF technology, and curve ② represents the performance of this channel access scheme. Figure 12a This is a schematic diagram comparing the packet loss rate of the present invention with that of the DCF mechanism in a mobile scenario, illustrating the trend of packet loss rate as the node moves; Figure 12b These two figures illustrate a comparison of network saturation throughput in mobile scenarios between the proposed method and the DCF mechanism, showing the trend of network saturation throughput as nodes move. As can be seen from these figures, the channel access mechanism proposed in this example also exhibits good robustness in mobile scenarios and consistently outperforms the DCF mechanism.

[0236] Meanwhile, even under conditions of unsaturated business load, this example solution still maintains good performance advantages. Figure 9 In this network topology environment, the node service load is not saturated, meaning that at any given moment, some nodes have data to send, while others may have zero data to send. Under this condition of unsaturated service load, the simulation results for packet loss rate and network throughput are as follows: Figure 13a and Figure 13bIn the figures, curve ① represents the performance of DCF technology, and curve ② represents the performance of the proposed solution. As can be seen from the two figures, the packet loss rate of curve ① is significantly higher than that of curve ②, and the network throughput of curve ① is lower than that of curve ②. This means that the channel access mechanism proposed in this example also exhibits superior performance under conditions of unsaturated service load. Therefore, this solution demonstrates broad adaptability, reducing packet loss rate and improving network throughput while ensuring robustness.

[0237] Furthermore, embodiments of this application also propose a channel access device, the channel access device comprising:

[0238] The acquisition module is used to acquire the situational information of the surrounding nodes of the target node before the start of the next decision cycle or when data packets need to be sent.

[0239] The determination module is used to determine the start time of the attempt to send window in the next decision cycle based on the surrounding node situation information;

[0240] The access module is used to control the target node to access the channel when the start time of the attempted transmission window is reached.

[0241] The principle and implementation process of channel access in this embodiment are explained in the above embodiments, and will not be repeated here.

[0242] Furthermore, this application also proposes a channel access device, which includes a memory, a processor, and a channel access program stored in the memory and executable on the processor. When the channel access program is executed by the processor, it implements the steps of the channel access method described above.

[0243] Since this channel access program employs all the technical solutions of all the aforementioned embodiments when executed by the processor, it has at least all the beneficial effects brought about by all the technical solutions of all the aforementioned embodiments, which will not be elaborated here.

[0244] Furthermore, embodiments of this application also propose a computer-readable storage medium storing a channel access program, which, when executed by a processor, implements the steps of the channel access method as described above.

[0245] Since this channel access program employs all the technical solutions of all the aforementioned embodiments when executed by the processor, it has at least all the beneficial effects brought about by all the technical solutions of all the aforementioned embodiments, which will not be elaborated here.

[0246] Compared to existing technologies, the channel access method, apparatus, device, and storage medium proposed in this application obtain the surrounding node situation information of the target node before the start of the next decision cycle or when data packets need to be sent; determine the start time of the attempt transmission window in the next decision cycle based on the surrounding node situation information; and control the target node to access the channel when the start time of the attempt transmission window is reached. Based on this application's solution, by obtaining the surrounding node situation information perceived by the target node itself and determining the start time of the attempt transmission window in the next decision cycle based on the surrounding node situation information, decisions can be made based on the communication situation of the target node's surrounding environment to determine the start time of the attempt transmission window that the target node can actively access, avoiding the control information overhead caused by dynamic time slot allocation between nodes; by controlling the target node to actively access the channel and send and receive data packets when the start time of the attempt transmission window is reached, collisions between nodes can be effectively avoided, greatly reducing the node packet loss rate, improving network throughput, and making the performance improvement more significant.

[0247] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0248] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0249] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0250] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a device (which may be a mobile phone, computer, server, controlled terminal, or network device, etc.) to execute the methods of each embodiment of this application.

[0251] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A channel access method, characterized in that, The channel access method includes: Before the start of the next decision cycle or when data packets need to be sent, obtain the situation information of the surrounding nodes of the target node; The start time of the attempt to send the signal in the next decision cycle is determined based on the situation information of the surrounding nodes. When the start time of the attempted transmission window is reached, control the target node to access the channel; The step of determining the start time of the attempt to send window in the next decision cycle based on the surrounding node situation information includes: Obtain node density parameters; Based on the surrounding node situation information, the number of surrounding nodes with a data volume greater than zero is counted to obtain the current network density. The start time of the attempt to send window in the next decision cycle is determined based on the current network density and the node density parameters.

2. The channel access method according to claim 1, characterized in that, The step of determining the start time of the attempt sending window in the next decision period based on the current network density and the node density parameters includes: Several decision-making cycles are obtained based on the target timeline; The duration of the attempted transmission window is determined based on the decision cycle, the current network density, and the node density parameters. A pseudo-random number interval is constructed based on the current network density and the node density parameters; Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval; The start time of the attempted transmission window is determined based on the start time of the next decision cycle, the pseudo-random integer, and the duration of the attempted transmission window.

3. The channel access method according to claim 1, characterized in that, The step of determining the start time of the attempt sending window in the next decision period based on the current network density and the node density parameters includes: Obtain the pre-set time frame length parameter; The next decision cycle is determined based on the time frame length parameter, the current network density, and the node density parameter. A pseudo-random number interval is constructed based on the current network density and the node density parameters; Select any pseudo-random integer from the uniform distribution of the pseudo-random number interval; The start time of the attempted transmission window is determined based on the start time of the next decision cycle, the pseudo-random integer, and the time frame length parameter.

4. The channel access method according to claim 1, characterized in that, The step of determining the start time of the attempt sending window in the next decision period based on the current network density and the node density parameters includes: The probability of the start time of the attempted sending window in the next decision period is calculated based on the current network density and the node density parameters. Construct a probability interval, and before the start of the next decision cycle or at the start of each time frame, select an arbitrary pseudo-random probability for each time frame from the uniform distribution of the probability interval. Compare the magnitudes of the starting time probability and the pseudo-random probability; If the pseudo-random probability is less than or equal to the starting time probability, then the starting time of the time frame corresponding to the pseudo-random probability is determined as the starting time of the attempted transmission window.

5. The channel access method according to claim 1, characterized in that, After the step of determining the start time of the attempt to send window in the next decision cycle based on the surrounding node situation information, the method further includes: The limited sending window is determined based on the attempted sending window in the next decision cycle; When the start time of the restricted transmission window is reached, the target node is controlled to be in a restricted transmission state.

6. The channel access method according to claim 1, characterized in that, After the step of controlling the target node to access the channel when the start time of the attempted transmission window is reached, the method further includes: When the end time of the attempted sending window is reached, determine the current send / receive process status of the target node; If the target node is in a random rollback state, the rollback count is frozen, the remaining rollback duration is saved, and the restricted sending window is entered. If the target node is in the request sending state, monitor the response result and control the target node to execute the corresponding processing flow based on the response result; If the target node is in a data transmission state, it will enter a restricted transmission window after the data transmission is completed. If the target node is in another state, then the restricted sending window is entered, wherein the other state is a non-random rollback, non-request sending, and non-data sending state.

7. The channel access method according to claim 1, characterized in that, Before the step of obtaining the situational information of the surrounding nodes of the target node, the method further includes: Using the target node as the maintenance center, the status information of surrounding nodes within a preset local status range of the target node is maintained, specifically including: Receive situation information of surrounding nodes within a preset local situation range of the target node; A local network situation information table is generated or updated based on the surrounding node situation information; The steps for obtaining the situational information of the surrounding nodes of the target node include: The local network situation information table is read, and the situation information of all surrounding nodes within the preset local situation range of the target node is extracted.

8. A channel access device, characterized in that, The channel access device includes: The acquisition module is used to acquire the situational information of the surrounding nodes of the target node before the start of the next decision cycle or when data packets need to be sent. The determination module is used to determine the start time of the attempt to send window in the next decision cycle based on the surrounding node situation information; The access module is used to control the target node to access the channel when the start time of the attempted transmission window is reached; The determining module is also used to obtain node density parameters; count the number of nodes with a data volume greater than zero among the surrounding nodes based on the surrounding node situation information to obtain the current network density; and determine the start time of the attempt to send window in the next decision cycle based on the current network density and the node density parameters.

9. A channel access device, characterized in that, The channel access device includes a memory, a processor, and a channel access program stored in the memory and executable on the processor. When the channel access program is executed by the processor, it implements the steps of the channel access method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a channel access program, which, when executed by a processor, implements the steps of the channel access method as described in any one of claims 1-7.

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