A dynamic timeslot allocation method, system, device, and medium

Abstract

The application discloses a dynamic time slot allocation method, system, device and medium, belongs to the technical field of mobile self-organizing network communication, and through constructing a time slot allocation table, collecting one-hop neighbor node information and establishing a link set, time slots of a network model are dynamically allocated based on the time slot allocation table and the link set, so that node reservation and channel resource recovery are realized, the time slot allocation problem in the mobile self-organizing network is effectively solved, random network entry and network exit of any node at any time can be completed, and the free expansion of the mobile self-organizing network can be realized. Meanwhile, the method can adjust the time slot allocation according to the current system, reduces the service delay, and improves the network throughput.

Description

Technical Field

[0001] This invention relates to the field of mobile ad hoc network communication technology, specifically to a dynamic time slot allocation method, system, device, and medium. Background Technology

[0002] Unlike conventional communication networks, mobile ad hoc networks do not rely on existing network communication and can quickly build a communication network anytime, anywhere. The network node structure is complete, possessing self-organization and independence. They are widely used in disaster relief and remote area communication environments. However, due to the characteristics of mobile ad hoc networks and the differentiated network requirements in various complex environments, the communication performance of mobile ad hoc networks cannot reach a sufficiently high level.

[0003] The channel access protocol in mobile ad hoc network (MAN) communication technology primarily addresses the following: it establishes rules for mobile nodes to access channels, specifically how to rationally allocate channel resources among all nodes in a MAN to efficiently utilize these resources and improve system performance. The choice of the MAC (Media Access Control) protocol depends on the network size and system load; therefore, the rational allocation of channel resources in MANs has become a pressing issue.

[0004] In current channel resource allocation schemes for mobile ad hoc networks, most adopt a static allocation method. Static allocation, or fixed allocation, assigns available channel resources to each mobile node in the network, preventing newly joined nodes from acquiring channel resources. When a node leaves the network, channel resources are not reclaimed, resulting in wasted resources and inefficient use of channel resources; latency is also difficult to guarantee. Therefore, in scenarios with dynamic changes in network nodes and a large number of nodes, fully utilizing channel resources and achieving reasonable dynamic allocation of channel resources is particularly important. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a dynamic time slot allocation method, system, device, and medium that can solve the technical issues of random network node entry and exit at any time, low throughput, and difficulty in guaranteeing latency. This method utilizes the dynamic allocation of channel resources by network nodes and system load, allowing nodes to reserve and reclaim channel resources, thus optimizing system performance and enabling random network entry and exit, achieving high throughput and low latency in mobile ad hoc networks.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A dynamic time slot allocation method includes the following steps:

[0008] S1: Construct a network model using multiple initial nodes;

[0009] S2: Initialize the number of time slots in the network model, determine the mapping relationship based on the initial nodes and corresponding time slots, and construct the time slot allocation table;

[0010] S3: Collect the one-hop neighbor node information of each initial node, establish a link set based on the one-hop neighbor node information, and update the time slot allocation table;

[0011] When a new node is to be added to the network model, it sends network access control information. The new node's one-hop neighbor node records the node's network access information based on the network access control information.

[0012] When an initial node is about to exit the network model, it sends a network exit control message. The one-hop neighbor node of the initial node records the node's network exit information according to the network exit control message.

[0013] S4: Send service information according to the time slot allocation table and link set;

[0014] S5: Based on the node joining and leaving information in S3, the new node officially joins the network model, and an initial node officially leaves the network model. Update the number of time slots, modify the mapping relationship, reset the time slot allocation table and delete the link set, and repeat S3 and S4.

[0015] Furthermore, in S1, the network model includes multiple time frames, each time frame including control subframes and data subframes. The control subframes include time slots for the network entry phase, time slots for the network exit phase, and time slots for the collection phase. The data subframes include time slots for transmitting services.

[0016] Furthermore, in S3, the specific steps for pre-adding new nodes to the network model are as follows:

[0017] When a new node is to be added to the network model, the new node first listens to the shared channel. After initializing the synchronization information, it sends network entry control information to the network model in the time slot of the node entry phase in the control subframe. The new node's one-hop neighbor node receives the network entry control information and records the node's network entry information. The network entry control information is a connect packet.

[0018] Furthermore, in S3, the specific steps for an initial node to pre-exit the network model are as follows:

[0019] When an initial node is about to exit the network model, it first listens to the shared channel and sends exit control information to the network model during the node exit phase time slot in the control subframe. The one-hop neighbor node of the initial node receives the exit control information and records the node exit information. The exit control information is a break packet.

[0020] Furthermore, the specific steps of S2 are as follows:

[0021] Based on the initial number of nodes, determine the number of time slots in the network model, map the IDs of the initial nodes to their corresponding time slots, and construct a time slot allocation table based on the mapping relationship.

[0022] Furthermore, the specific steps of S4 are as follows:

[0023] Look up the time slot allocation table. If the send flag of the current time slot of the initial node is true, then send the service information.

[0024] If the send flag is false, it is determined whether other time slots of the initial node have service transmissions. If there are service transmissions, and the conditions are met, such as no other initial node in the current time slot transmitting services or the distance between the transmitting nodes in the current time slot being more than two hops apart, the send flag is modified and the service information of the initial node is sent. Otherwise, no service information is sent.

[0025] Furthermore, the specific steps of S5 are as follows:

[0026] Based on the node joining information in S3, the new node officially joins the network model, the number of time slots is increased, and the mapping relationship between the new node and its corresponding time slot is added;

[0027] Based on the node decommissioning information in S3, an initial node officially exits the network model, the number of time slots is reduced, and the mapping relationship between the initial node and its corresponding time slot is deleted.

[0028] Reset the time slot allocation table and delete the link set, then repeat steps S3 and S4.

[0029] A dynamic time slot allocation system, comprising:

[0030] Builder modules are used to build network models using initial nodes;

[0031] The module is used to initialize the number of time slots in the network model, determine the mapping relationship based on the initial nodes and corresponding time slots, and construct a time slot allocation table.

[0032] The collection module is used to collect the one-hop neighbor node information of each initial node, establish a link set based on the one-hop neighbor node information, and update the time slot allocation table;

[0033] When a new node is to be added to the network model, it sends network access control information. The new node's one-hop neighbor node records the node's network access information based on the network access control information.

[0034] When an initial node is about to exit the network model, it sends a network exit control message. The one-hop neighbor node of the initial node records the node's network exit information according to the network exit control message.

[0035] The service transmission module is used to send service information according to the time slot allocation table and link set;

[0036] The reset module is used to formally add new nodes to the network model and formally remove an initial node from the network model based on the node joining and leaving information in S3. It also updates the number of time slots, modifies the mapping relationship, resets the time slot allocation table, deletes the link set, and repeats S3 and S4.

[0037] An apparatus comprising:

[0038] Memory, used to store computer programs;

[0039] A processor is used to implement the steps of the above-described dynamic time slot allocation method when executing the computer program.

[0040] A computer-readable storage medium storing a computer program, which, when executed by a processor, is used to implement the steps of the dynamic time slot allocation method of claim 1.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] This invention provides a dynamic time slot allocation method. By constructing a time slot allocation table, collecting one-hop neighbor node information, and establishing a link set, the time slots of the network model are dynamically allocated based on the time slot allocation table and the link set. This allows nodes to reserve and reclaim channel resources, effectively solving the time slot allocation problem in mobile ad hoc networks. It enables any node to randomly join and leave the network at any time, allowing for the free expansion of mobile ad hoc networks. Furthermore, this method can adjust time slot allocation according to the current system, reducing service latency and improving network throughput. Attached Figure Description

[0043] Figure 1 This is a flowchart of a dynamic time slot allocation method provided in Embodiment 1 of the present invention;

[0044] Figure 2 This is a schematic diagram of the time frame structure provided in Embodiment 1 of the present invention;

[0045] Figure 3 This is a schematic diagram of nodes when constructing the initial network model as provided in Embodiment 1 of the present invention;

[0046] Figure 4 This is a schematic diagram of nodes when constructing a time slot allocation table as provided in Embodiment 1 of the present invention;

[0047] Figure 5 This is a schematic diagram of the node at the end of this time slot provided in Embodiment 1 of the present invention;

[0048] Figure 6 This is a schematic diagram of a node joining the network according to Embodiment 2 of the present invention;

[0049] Figure 7 This is a schematic diagram of node decommissioning involved in Embodiment 2 of the present invention;

[0050] Figure 8 This is a schematic diagram comparing the throughput performance of the dynamic time slot allocation system and the static time slot allocation system provided in Embodiment 2 of the present invention;

[0051] Figure 9 This is a schematic diagram comparing the average time delay performance of the dynamic time slot allocation method and the static time slot allocation method provided in Embodiment 2 of the present invention. Detailed Implementation

[0052] This invention provides a dynamic time slot allocation method, comprising the following steps:

[0053] A dynamic time slot allocation method includes the following steps:

[0054] S1: Construct a network model using multiple initial nodes; the network model includes multiple time frames, each time frame including control subframes and data subframes, the control subframe including time slots for the network entry phase, time slots for the network exit phase, and time slots for the collection phase, and the data subframe including time slots for transmitting services.

[0055] S2: Initialize the number of time slots in the network model, determine the mapping relationship based on the initial nodes and their corresponding time slots, and construct a time slot allocation table; specifically: determine the number of time slots in the network model based on the number of initial nodes, generate a mapping relationship between the ID number of the initial nodes and their respective time slots, and construct a time slot allocation table based on the mapping relationship.

[0056] S3: Collect the one-hop neighbor node information of each initial node, establish a link set based on the one-hop neighbor node information, and update the time slot allocation table;

[0057] When a new node is to be added to the network model, it sends network access control information. The new node's one-hop neighbor node records the node's network access information based on the network access control information.

[0058] When an initial node is about to exit the network model, it sends a network exit control message. The one-hop neighbor node of the initial node records the node's network exit information according to the network exit control message.

[0059] The specific steps for pre-adding a new node to the network model are as follows:

[0060] When a new node is to be added to the network model, the new node first listens to the shared channel. After initializing the synchronization information (to make the new node's time consistent with the network model), it sends network entry control information to the network model in the time slot of the node entry phase in the control subframe. The new node's one-hop neighbor node receives the network entry control information and records the node's network entry information. The network entry control information is a connect packet.

[0061] The specific steps for an initial node to pre-exit the network model are as follows:

[0062] When an initial node is about to exit the network model, it first listens to the shared channel and sends exit control information to the network model during the node exit phase time slot in the control subframe. The one-hop neighbor node of the initial node receives the exit control information and records the node exit information. The exit control information is a break packet.

[0063] S4: Send service information according to the time slot allocation table and link set; specifically: look up the time slot allocation table. If the sending flag of the current time slot of the initial node is true in the time slot allocation table, then send the service information.

[0064] If the sending flag is false, it is determined whether other time slots of the initial node have service transmission. If there is service transmission and the conditions are met, such as no other initial node transmitting service in the current time slot or the transmission nodes in the current time slot being more than two hops apart, the sending flag is modified and the service information of the initial node is sent. Otherwise, no service information is sent.

[0065] Here, true indicates that there is a service being sent in the current time slot, and false indicates that there is a service being sent in the current time slot.

[0066] S5: Based on the node joining information in S3, the new node officially joins the network model, the number of time slots is increased, and the mapping relationship between the new node and its corresponding time slot is added;

[0067] Based on the node decommissioning information in S3, an initial node officially exits the network model, the number of time slots is reduced, and the mapping relationship between the initial node and its corresponding time slot is deleted.

[0068] Reset the time slot allocation table and delete the link set, then repeat steps S3 and S4.

[0069] This invention also provides a dynamic time slot allocation system, comprising: a construction module, a setup module, a collection module, a service transmission module, and a reset module; the construction module is used to construct a network model using initial nodes; the setup module is used to initialize the number of time slots in the network model, determine the mapping relationship based on the initial nodes and corresponding time slots, and construct a time slot allocation table; the collection module is used to collect the one-hop neighbor node information of each initial node, establish a link set based on the one-hop neighbor node information, and update the time slot allocation table; when a new node is to be added to the network model, it sends network entry control information, and the one-hop neighbor node of the new node records the node's network entry information based on the network entry control information; when an initial node is to be removed from the network model, it sends network exit control information, and the one-hop neighbor node of the initial node records the node's network exit information based on the network exit control information; the service transmission module is used to send service information based on the time slot allocation table and the link set; the reset module is used to, based on the node network entry information and node network exit information in S3, when a new node officially joins the network model, when an initial node officially leaves the network model, update the number of time slots, modify the mapping relationship, reset the time slot allocation table and delete the link set, and repeat S3 and S4.

[0070] The present invention also provides an apparatus comprising: a memory for storing a computer program; and a processor for executing the computer program to implement the steps of the dynamic time slot allocation method.

[0071] When the processor executes the computer program, it implements the steps of the above-described dynamic time slot allocation method, for example: constructing a network model using initial nodes; initializing the number of time slots in the network model, determining the mapping relationship based on the initial nodes and corresponding time slots, and constructing a time slot allocation table; collecting the one-hop neighbor node information of each initial node, establishing a link set based on the one-hop neighbor node information, and updating the time slot allocation table; when a new node is about to join the network model, it sends network entry control information, and the one-hop neighbor node of the new node records the node's network entry information based on the network entry control information; when an initial node is about to leave the network model, it sends network exit control information, and the one-hop neighbor node of the initial node records the node's network exit information based on the network exit control information; sending service information based on the time slot allocation table and the link set; based on the node network entry information and node network exit information in S3, the new node officially joins the network model, the initial node officially leaves the network model, the number of time slots is updated, the mapping relationship is modified, the time slot allocation table is reset and the link set is deleted, and S3 and S4 are repeated.

[0072] Alternatively, when the processor executes the computer program, it implements the functions of each module in the above system, such as: a construction module, a setup module, a collection module, a service transmission module, and a reset module; the construction module is used to build a network model using initial nodes; the setup module is used to initialize the number of time slots in the network model, determine the mapping relationship based on the initial nodes and corresponding time slots, and build a time slot allocation table; the collection module is used to collect the one-hop neighbor node information of each initial node, establish a link set based on the one-hop neighbor node information, and update the time slot allocation table; when a new node is to be added to the network model, it sends network access control information, and the new node... A node's one-hop neighbor node records the node's network entry information based on the network entry control information. When an initial node is about to exit the network model, it sends network exit control information, and the initial node's one-hop neighbor node records the node's network exit information based on the network exit control information. The service sending module is used to send service information based on the time slot allocation table and link set. The reset module is used to update the number of time slots, modify the mapping relationship, reset the time slot allocation table and delete the link set based on the node network entry information and node network exit information in S3, and repeat S3 and S4.

[0073] For example, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of performing a preset function, the instruction segments describing the execution process of the computer program in the dynamic time slot allocation device. For example, the computer program can be divided into a construction module, a setup module, a collection module, a service transmission module, and a reset module; the specific functions of each module are as follows: the construction module is used to build a network model using initial nodes; the setup module is used to initialize the number of time slots in the network model, determine the mapping relationship based on the initial nodes and corresponding time slots, and build a time slot allocation table; the collection module is used to collect the one-hop neighbor node information of each initial node, establish a link set based on the one-hop neighbor node information, and update the time slot allocation table; when a new node is to be added to the network model, it sends network entry control information, and the one-hop neighbor node of the new node records the node's network entry information based on the network entry control information; when an initial node is to be removed from the network model, it sends network exit control information, and the one-hop neighbor node of the initial node records the node's network exit information based on the network exit control information; the service transmission module is used to send service information based on the time slot allocation table and the link set; the reset module is used to, based on the node network entry information and node network exit information in S3, to formally add a new node to the network model, formally remove an initial node from the network model, update the number of time slots, modify the mapping relationship, reset the time slot allocation table and delete the link set, and repeat S3 and S4.

[0074] The dynamic time slot allocation device can be a computing device such as a desktop computer, laptop, handheld computer, or cloud server. The dynamic time slot allocation device may include, but is not limited to, a processor and memory. Those skilled in the art will understand that the above are examples of dynamic time slot allocation devices and do not constitute a limitation on them. The device may include more components than described above, or combine certain components, or use different components. For example, the dynamic time slot allocation device may also include input / output devices, network access devices, buses, etc.

[0075] The processor referred to can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor, or any conventional processor, etc. The processor is the control center of the dynamic time slot allocation, connecting various parts of the dynamic time slot allocation device via various interfaces and lines.

[0076] The memory can be used to store the computer program and / or modules. The processor implements various functions of the dynamic time slot allocation device by running or executing the computer program and / or modules stored in the memory and calling the data stored in the memory.

[0077] The memory may primarily include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a given function (such as sound playback or image playback). The data storage area may store data created based on the use of the phone (such as audio data or a phonebook). Furthermore, the memory may include high-speed random access memory (RAM) and non-volatile memory, such as hard disks, RAM, plug-in hard disks, SmartMediaCards (SMC), Secure Digital (SD) cards, flash cards, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.

[0078] The present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the dynamic time slot allocation method described above.

[0079] If the modules / units integrated in the dynamic time slot allocation system are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium.

[0080] Based on this understanding, the present invention can implement all or part of the processes in the above-described dynamic time slot allocation method, or it can be accomplished by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of the above-described roundabout channelization and signal timing optimization method. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or a preset intermediate form, etc.

[0081] The computer-readable storage medium may include: any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0082] It should be noted that the content contained in the computer-readable storage medium may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable storage medium does not include electrical carrier signals and telecommunication signals.

[0083] Example 1

[0084] The present invention will be further described below with reference to Embodiment 1 and the accompanying drawings:

[0085] The time frame structure provided in Example 1 is as follows: Figure 2 As shown, in the network model, the entire transmission channel's time domain is divided into time frames. Each time frame is further divided into two sub-parts: control subframes and data subframes. Each control subframe is further divided into three sub-stages: time slots for the network entry stage, time slots for the network exit stage, and time slots for the collection stage. The data subframe contains the data stage. The length of the time frame and the number of time slots are determined by the number of nodes in the network model. Since this embodiment provides a dynamic time slot allocation method for use in mobile ad hoc networks, all nodes mentioned are mobile ad hoc nodes, hereinafter referred to as nodes.

[0086] like Figure 1 As shown in the figure, the dynamic time slot allocation method provided in this embodiment includes the following steps:

[0087] S1: Construct a network model using multiple initial nodes; the network model includes multiple time frames, each time frame including control subframes and data subframes, the control subframe including time slots for the network entry phase, time slots for the network exit phase, and time slots for the collection phase, and the data subframe including time slots for transmitting services.

[0088] The scenario considered in this invention is a mobile ad hoc communication network in which nodes in the network model dynamically change and move. The network consists of several mobile ad hoc nodes (hereinafter referred to as nodes), each node is responsible for its own communication, and the nodes in the network model complete channel access and data transmission and reception through periodic time frames.

[0089] The current node begins initialization, obtains the node ID number, sequentially increases the number of time slots, numbers the time slots and maps them one-to-one with the obtained network node ID numbers, thus creating a mapping.

[0090] S2: Initialize the number of time slots in the network model, determine the mapping relationship based on the initial nodes and their corresponding time slots, and construct a time slot allocation table; specifically: based on the number of initial nodes N, determine that the number of time slots in the network model is also N, generate a mapping relationship between the ID number of the initial nodes and their respective time slots, construct a time slot allocation table based on the mapping relationship, and prepare for control subframes and data subframes.

[0091] S3: Collect the one-hop neighbor node information of each initial node, establish a link set based on the one-hop neighbor node information, and update the time slot allocation table;

[0092] When a new node is to be added to the network model, it sends network access control information. The new node's one-hop neighbor node records the node's network access information based on the network access control information.

[0093] When an initial node is about to exit the network model, it sends a network exit control message. The one-hop neighbor node of the initial node records the node's network exit information according to the network exit control message.

[0094] The specific steps for pre-adding a new node to the network model are as follows:

[0095] When a new node is to be added to the network model, the new node first listens to the shared channel. After initializing the synchronization information (to make the new node's time consistent with the network model), it sends network entry control information to the network model in the time slot of the node entry phase in the control subframe. The new node's one-hop neighbor node receives the network entry control information and records the node's network entry information. The network entry control information is a connect packet.

[0096] The specific steps for an initial node to pre-exit the network model are as follows:

[0097] When an initial node is about to exit the network model, it first listens to the shared channel and sends exit control information to the network model during the node exit phase time slot in the control subframe. The one-hop neighbor node of the initial node receives the exit control information and records the node exit information. The exit control information is a break packet.

[0098] To further explain: When a new node joins the network, it first listens to the shared channel. After initializing synchronization information, it broadcasts a connect packet to the network model during the node joining phase in the control subframe. At this time, the new node's one-hop neighbor receives the connect packet, records the joining information, and then sends back a joining packet based on the packet information. The new node receives the returned joining packet, confirming its joining the network in the next time frame. It should be noted that when a new node broadcasts a connect packet, more than one node may receive the packet; in this case, only one joining information needs to be recorded. The scheme provided in this embodiment allows multiple new nodes to join the network simultaneously.

[0099] When an initial node needs to leave the network, it listens to the shared channel. When it reaches the time slot for the node's exit phase, it broadcasts a break packet to the network. The one-hop neighbor node that receives the break packet records the exit information and also sends an exit packet back to the exiting node. When the initial node receives the returned exit packet, it confirms that it will exit the network in the next frame.

[0100] During the collection phase, each node sends control information in its respective time slot by looking up the mapping relationship between time slot nodes. A one-hop neighbor node receives the control information, extracts the sending node ID number, records the link with its own ID number, and adds it to the link set. It then retrieves the flag bit for the sending node's service and modifies the corresponding flag bit in the time slot allocation table. If a service is being sent, the flag bit is set to true; otherwise, it is set to false. The one-hop neighbor nodes of node i are:

[0101] S i ={S(i,j),S(i,k),...}

[0102] S i Let j be the set of links with node ID i, where j and k are both one-hop neighbors of node i.

[0103] S4: Send service information according to the time slot allocation table and link set; specifically: look up the time slot allocation table. If the sending flag of the current time slot of the initial node is true in the time slot allocation table, then send the service information.

[0104] If the sending flag is false, it is determined whether other time slots of the initial node have service transmission. If there is service transmission and the conditions are met, such as no other initial node transmitting service in the current time slot or the transmission nodes in the current time slot being more than two hops apart, the sending flag is modified and the service information of the initial node is sent. Otherwise, no service information is sent.

[0105] Here, true indicates that there is a service being sent in the current time slot, and false indicates that there is a service being sent in the current time slot.

[0106] To explain further:

[0107] The time slot allocation table is searched. If a node's transmit flag for the current time slot is true in the table, then the service information is transmitted. If it is false, the system first checks if any service is being transmitted. If so, it then checks if no node is transmitting service in the current time slot, or checks the link set to determine if any transmitting nodes in the current time slot are more than two hops apart. If the conditions are met, the flag in the time slot allocation table is modified, and the service information is transmitted. The two-hop distance H can be represented as:

[0108] H (i,l) =S(i,j)∧S(j,k)

[0109] If node l is neither node j nor node k, it means that node l is more than two hops away from node i.

[0110] S5: Based on the node joining information in S3, the new node officially joins the network model, the number of time slots is increased, and the mapping relationship between the new node and its corresponding time slot is added;

[0111] Based on the node decommissioning information in S3, an initial node officially exits the network model, the number of time slots is reduced, and the mapping relationship between the initial node and its corresponding time slot is deleted.

[0112] Reset the time slot allocation table and delete the link set, then repeat steps S3 and S4.

[0113] The specific implementation example of the dynamic time slot allocation method provided in this embodiment is as follows:

[0114] like Figure 3 As shown, step 1, construct the initial network model; assuming there are four nodes A, B, C, and D in this network model, the four circles from left to right represent the communication range of A, B, C, and D respectively. Therefore, A and B, B and C, and C and D are each one-hop neighbor nodes, A and C, B and D are each two-hop neighbor nodes, and A and D are each three-hop neighbor nodes.

[0115] For example Figure 3As shown in the figure, in step 2, the number of time slots in the network model is initialized, the mapping relationship is determined according to the initial mobile ad hoc nodes and the corresponding time slots, and a time slot allocation table is constructed. As shown in the figure, there are 4 nodes, the number of time slots is 4, and the mapping relationship is determined according to the initial mobile ad hoc nodes and the corresponding time slots, and a time slot allocation table is constructed. The time slot allocation table is shown in Table 1.

[0116] Table 1 - Initial Time Slot Allocation Table

[0117] Node A Node B Node C Node D Time slot 0 FALSE FALSE FALSE FALSE Time slot 1 FALSE FALSE FALSE FALSE Time slot 2 FALSE FALSE FALSE FALSE Time slot 3 FALSE FALSE FALSE FALSE

[0118] like Figure 4 As shown in step 3, suppose a new mobile ad hoc node E wants to pre-join the network model. Node E sends control information during the network entry phase. Node B collects the network entry control information and records the node's network entry information based on the network entry control information. Suppose that an initial mobile ad hoc network node D wants to pre-exit the network model. Node C collects the network exit control information and records the exit information based on the network exit control information.

[0119] Upon reaching the control phase, assuming that node A has service transmission, node B has service transmission, node C has no service transmission, and node D has service transmission, the one-hop neighbor node information of the initial mobile ad hoc nodes A, B, C, and D is collected to form the link set S and the time slot allocation table is updated to Table 2.

[0120] When sub-slot 0 of the control phase is reached, node A sends control information. Node A has service to send, updates the slot allocation table, and adds link (A, B) to the link set.

[0121] When sub-slot 1 of the control phase arrives, node B sends control information. Node B has service to send, so it updates the slot allocation table and adds links (B, A) and (B, C) to the link set. Since link (A, B) is already in the link set, there is no need to add link (B, A) at this time.

[0122] When the control phase reaches sub-slot 2, node C sends control information. Node C has no service to send, so it adds links (C, B) and (C, D) to the link set. Since link (B, C) is already in the link set, it does not need to add link (C, B) at this time.

[0123] When sub-slot 3 of the control phase arrives, node D sends control information. Node D has service to send, so it updates the slot allocation table and adds link (D, C) to the link set. Since link (C, D) is already in the link set, it is not necessary to add link (D, C) at this time.

[0124] S = {(A,B),(B,C),(C,D)}

[0125] Table 2 - Updated Time Slot Allocation Table

[0126] Node A Node B Node C Node D Time slot 0 TRUE FALSE FALSE FALSE Time slot 1 FALSE TRUE FALSE FALSE Time slot 2 FALSE FALSE FALSE FALSE Time slot 3 FALSE FALSE FALSE TRUE

[0127] like Figure 4 As shown, in step 4, the data phase begins, where service information is sent according to the time slot allocation table and link set.

[0128] Upon reaching sub-slot 0 in the data phase, node A checks the slot allocation table and finds [slot 0][node A] = TRUE, so it sends the service. Node B checks the slot allocation table and finds [slot 0][node B] = FALSE, so it determines that node B has a service to send. It then checks the link set and finds (A, B), so it does not send the service. Node C checks the slot allocation table and finds [slot 0][node C] = FALSE, so it determines that node C has no service to send and does not send the service. Node D checks the slot allocation table and finds [slot 0][node D] = TRUE, so it has a service to send. It then checks the link set and finds that node D is three hops away from node A, so it sends the service and modifies [slot 0][node D] = TRUE.

[0129] Upon reaching sub-slot 1 in the data phase, node B checks the slot allocation table [slot 1][node B] = TRUE and sends the service. Assuming node A has already sent its service, node A checks the slot allocation table [slot 1][node A] = FALSE. Since node A has no service to send, it does not send any service. Node C checks the slot allocation table [slot 1][node C] = FALSE. Since node C has no service to send, it does not send any service. Node D checks the slot allocation table [slot 1][node D] = FALSE. Since node D has service to send, it checks the link set and finds that (B, C) and (C, D) are two hops apart, so it does not send any service.

[0130] Upon reaching sub-slot 2 in the data phase, node C checks the slot allocation table [Slot 2][Node C] = FALSE, indicating no service is being sent, so no service is sent. Node A has already completed its service transmission, so it checks the slot allocation table [Slot 2][Node A] = FALSE, indicating no service is being sent, so no service is sent. Node C checks the slot allocation table [Slot 1][Node C] = FALSE, indicating no service is being sent, so no service is sent. Node D checks the slot allocation table [Slot 2][Node D] = TRUE, indicating service is being sent. Since no node is sending service in slot 2, the service is sent, and [Slot 2][Node D] is updated to TRUE.

[0131] Upon reaching sub-slot 3 in the data phase, node D checks the slot allocation table [slot 3][node D] = TRUE and sends the service. Node A has already completed sending its service, so it checks the slot allocation table [slot 3][node A] = FALSE. Since node A has no service to send, it does not send any service. Node B has also completed sending its service, so it checks the slot allocation table [slot 3][node B] = FALSE. Since node B has no service to send, it does not send any service. Node C checks the slot allocation table [slot 3][node C] = FALSE. Since node C has no service to send, it does not send any service.

[0132] like Figure 5 As shown, based on the network entry and exit information collected in step 3, the new mobile ad hoc node E officially joins the network model, the initial mobile ad hoc node D officially exits the network model, the number of time slots is updated, the mapping relationship is modified, the time slot allocation table is reset to Table 3, and the link set is cleared. At this time, the network model is as follows: Figure 4 As shown, repeat steps four and five.

[0133] Table 3 - Reset Time Slot Allocation Table

[0134] Node A Node B Node C Node E Time slot 0 FALSE FALSE FALSE FALSE Time slot 1 FALSE FALSE FALSE FALSE Time slot 2 FALSE FALSE FALSE FALSE Time slot 3 FALSE FALSE FALSE FALSE

[0135] Example 2

[0136] The present invention will be further described below with reference to Embodiment 2 and the accompanying drawings, focusing on the experimental results:

[0137] Taking a scalable mobile ad hoc network as an example, the network consists of a mobile node with ID 11 that wants to join the network and 10 nodes with IDs 1 to 10 (hereinafter referred to as nodes). Node 11 applies to join the network at 30 seconds, and node with ID 3 applies to leave the network at 20 seconds. All nodes move freely and randomly within a 3km x 3km topology area. Within a time frame, the positions of mobile nodes in the network remain almost unchanged. No node in the network is an isolated node. The links between nodes in the network are noise-free and symmetrical. Nodes in the network cannot receive and transmit simultaneously.

[0138] The dynamic time slot allocation method (E-TDMA) provided in this embodiment, through eight experiments, can achieve random network entry and exit of nodes at any time. Figure 6 As shown, Node 11 requests network access at 30 seconds and arrives at the node network access phase time slot within the frame at approximately 37.2 seconds. Node 11 sends control information and then officially joins the network after the end of this frame; as... Figure 7 As shown, node 3 requests to leave the network at 20 seconds and arrives at the node leaving the network time slot in the frame at around 27.4 seconds. Node 3 sends control information and then officially joins the network after the end of this frame.

[0139] like Figure 8 As shown, the Dynamic Time Slot Allocation Method (E-TDMA) provided in this embodiment, compared with the Static Time Slot Allocation Method, effectively improves system performance, increases throughput, and reduces latency. Under the same conditions, due to spatial reuse, each time slot transmits services from its current mapped node and other nodes that meet the conditions as much as possible. Therefore, in these eight experiments, the throughput of the Dynamic Time Slot Allocation Method is higher than that of the Static Time Slot Allocation Method (TDMA).

[0140] like Figure 9 As shown, after eight experiments, the average latency of E-TDMA is significantly lower than that of the static time slot allocation method. In the static time slot allocation method, channel resources are fixedly allocated to mobile nodes in the network, and each node can only transmit services within the pre-allocated channel resources. Furthermore, due to the limited mobility and coverage of mobile nodes, some services cannot be transmitted to the destination node in a timely manner, resulting in a higher average latency. E-TDMA, however, utilizes the characteristics of mobile ad hoc networks. When two nodes are more than two hops apart, they do not interfere with each other. Therefore, through the interaction of control information in the control subframe, each time slot allocated to a node has the opportunity to transmit services more promptly. For the dynamic time slot allocation method in this embodiment, the system average latency is lower than that of the static time slot allocation method.

[0141] The above embodiments are merely one of the implementation methods for achieving the technical solution of the present invention. The scope of protection claimed by the present invention is not limited to this embodiment, but also includes any variations, substitutions and other implementation methods that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention.

Claims

1. A dynamic time slot allocation method, characterized by, The method comprises the following steps: S1: constructing a network model by using a plurality of initial nodes; S2: initializing the number of time slots of the network model, determining a mapping relationship according to the initial nodes and corresponding time slots, and constructing a time slot allocation table; S3: collecting one-hop neighbor node information of each initial node, establishing a link set according to the one-hop neighbor node information, and updating the time slot allocation table; When a new node is about to join the network model, the new node sends network access control information, and a one-hop neighbor node of the new node records node network access information according to the network access control information; When a certain initial node is about to exit the network model, the certain initial node sends network exit control information, and a one-hop neighbor node of the certain initial node records node network exit information according to the network exit control information; S4: sending service information according to the time slot allocation table and the link set; S5: according to the node network access information and the node network exit information in S3, a new node formally joins the network model, a certain initial node formally exits the network model, the number of time slots is updated, the mapping relationship is modified, the time slot allocation table is reset and the link set is deleted, and S3 and S4 are repeatedly executed.

2. The method of claim 1, wherein, In S1, the network model comprises a plurality of time frames, the time frames comprise control subframes and data subframes, the control subframes comprise time slots in a network access stage, time slots in a network exit stage and time slots in a collection stage, and the data subframes comprise time slots for sending services.

3. The method of claim 2, wherein, In S3, the specific steps for the new node to join the network model are as follows: When a new node is about to join the network model, the new node first listens to a shared channel, after initializing synchronization information, sends network access control information to the network model in a time slot in the node network access stage in the control subframes, a one-hop neighbor node of the new node receives the sent network access control information, records node network access information, and the network access control information is a connect packet.

4. The method of claim 2, wherein, In S3, the specific steps for the certain initial node to exit the network model are as follows: When a certain initial node is about to exit the network model, the certain initial node first listens to a shared channel, sends network exit control information to the network model in a time slot in the node network exit stage in the control subframes, a one-hop neighbor node of the certain initial node receives the sent network exit control information, records node network exit information, and the network exit control information is a break packet.

5. The method of claim 1, wherein, The specific steps of S2 are as follows: According to the number of initial nodes, the number of time slots of the network model is determined, a mapping relationship between the ID numbers of the initial nodes and the respective corresponding time slots is generated, and a time slot allocation table is constructed according to the mapping relationship.

6. The method of claim 1, wherein, The specific steps of S4 are as follows: Looking up the time slot allocation table, if a sending flag bit of a current time slot of an initial node is true in the time slot allocation table, service information is sent; If the sending flag bit is false, it is determined whether there is service sending in other time slots of the initial node, if there is service sending and any one of the following conditions is met, the sending flag bit is modified and service information of the initial node is sent: there is no service sending of other initial nodes in the current time slot or the distance between the sending nodes in the current time slot is more than two hops away as determined by the link set; otherwise, no service information is sent.

7. The method of claim 1, wherein, The specific steps of S5 are as follows: According to the node network access information in S3, a new node formally joins the network model, the number of time slots is increased, and a mapping relationship between the new node and the corresponding time slots is added; According to the node exit information in S3, an initial node formally exits the network model, the number of time slots is reduced, and the mapping relationship between the initial node and the corresponding time slot is deleted; Reset the time slot allocation table and delete the link set, repeat S3 and S4.

8. A dynamic time slot allocation system, characterized by, Comprise: A construction module for constructing a network model with initial nodes; A building module for initializing the number of time slots of the network model, determining the mapping relationship according to the initial nodes and the corresponding time slots, and constructing a time slot allocation table; A collection module for collecting one-hop neighbor node information of each initial node, establishing a link set according to the one-hop neighbor node information, and updating the time slot allocation table; When a new node is about to join the network model, send the network control information, and the one-hop neighbor node of the new node records the node network information according to the network control information; When a certain initial node is about to exit the network model, send the exit control information, and the one-hop neighbor node of the certain initial node records the node exit information according to the exit control information; A service sending module for sending service information according to the time slot allocation table and the link set; A reset module for updating the number of time slots, modifying the mapping relationship, resetting the time slot allocation table and deleting the link set according to the node network information and the node exit information in S3, and repeating S3 and S4.

9. An apparatus, comprising: Comprise: A memory for storing a computer program; A processor for executing the computer program to implement the steps of the dynamic time slot allocation method of any one of claims 1-7.

10. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 9. The computer program is executed by the processor to implement the steps of the dynamic time slot allocation method of any one of claims 1-7.

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