Ultra-wideband wireless ad hoc network construction method based on TDMA and DSDV and ad hoc network node equipment

Abstract

The invention discloses an ultra-wideband wireless ad hoc network construction method based on TDMA and DSDV and ad hoc network node equipment, and belongs to the field of wireless communication. The problems that an existing UWB ad hoc network is high in data transmission failure rate, and real-time communication is difficult to meet are solved. The method comprises the following steps: configuring network parameters; a communication period is divided into a synchronization frame, a routing frame and at least one data subframe, and communication time slots are distributed for nodes in a network based on a TDMA protocol; in the synchronization frame, a specified node broadcasts a synchronization packet containing a period starting point timestamp, and other nodes receive the synchronization packet and calibrate a local clock according to the synchronization packet; in the routing frame, each node broadcasts the DSDV routing table in the distributed time slot, and the neighbor node receives the DSDV routing table and updates the own routing table according to the serial number and the hop count; and in the data sub-frame, each node performs data transmission in the allocated time slot based on the updated routing table, and a verification mechanism is adopted to ensure the data integrity. The method is used in the high-speed stable data transmission field.

Description

A method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV, and an ad hoc network node device. Technical Field

[0001] This invention belongs to the field of wireless communication, and in particular relates to a method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV. Background Technology

[0002] Wireless Ad-hoc Networks (WANETs), as distributed networks that do not rely on a central infrastructure and can self-organize, possess irreplaceable value in scenarios requiring rapid deployment and high flexibility, such as military communications, emergency rescue, and environmental monitoring. In this field, existing technological solutions are mostly built upon traditional wireless communication technologies such as Wi-Fi, Zigbee, and Bluetooth. While these technologies have achieved success in some applications, such as the widespread use of Zigbee in low-power sensor networks, their performance and adaptability are significantly insufficient when facing the demands for high-speed, stable data transmission in complex environments (such as industrial sites or field environments with severe multipath fading and high-intensity electromagnetic interference). This is mainly manifested in inherent defects such as limited bandwidth, weak anti-interference capabilities, and the difficulty in balancing transmission distance and data rate.

[0003] To overcome the aforementioned shortcomings, Ultra Wideband (UWB) technology, with its extremely wide signal bandwidth, extremely high time resolution, excellent resistance to multipath fading, and high-precision positioning potential, is considered a promising alternative. UWB technology utilizes nanosecond-level narrow pulses for communication, enabling high-speed data transmission and accurate ranging, and has demonstrated unique advantages in fields such as radar positioning and wireless sensor networks. However, applying UWB technology to large-scale, highly dynamic wireless ad hoc networks still faces significant challenges. The core issue lies in how to effectively manage dynamically changing network topologies and, on this basis, achieve efficient and collision-free communication between nodes, which directly affects the reliability and overall performance of the network.

[0004] In terms of routing management, the Destination-Sequenced Distance Vector (DSDV) routing protocol, as a classic table-driven routing protocol, avoids routing loops by maintaining a sequence number for each routing entry, and performs stably in static networks of a certain size. However, when applied to UWB ad hoc network environments with frequently changing topologies, its inherent defects are amplified: nodes need to periodically broadcast the entire routing table across the network to maintain information synchronization, which generates huge control overhead and consumes valuable bandwidth resources that could be used for data transmission. More importantly, the DSDV protocol's route updates are lagging, unable to respond in real time to rapid network changes, resulting in outdated path information in highly dynamic environments, high data transmission failure rates, and difficulty in meeting the requirements of real-time communication.

[0005] In media access control, Time Division Multiple Access (TDMA), as a common channel-sharing mechanism, avoids collisions by allocating independent time slots to each node. However, traditional TDMA protocols perform poorly in UWB ad hoc networks with high node density and large data traffic. Their static or semi-static time slot allocation strategies struggle to adapt to the dynamic joining and leaving of nodes, easily leading to uneven time slot resource allocation: some nodes experience time slot shortages and increased communication latency, while others have idle time slots, resulting in wasted resources. Furthermore, network-wide time synchronization is a prerequisite for effective TDMA operation, and achieving and maintaining high-precision time synchronization in ad hoc networks without a central node is itself a technical challenge. Time slot conflicts and time slot overlaps caused by synchronization errors further trigger packet collisions, severely reducing network throughput.

[0006] In summary, existing technologies suffer from a clear disconnect: the physical layer advantages of UWB technology have not been effectively integrated with network and link layer protocols adapted to its characteristics. Using DSDV or TDMA mechanisms alone cannot solve the core problems faced by UWB ad hoc networks in highly dynamic and high-density scenarios, such as high routing update overhead, high latency, inflexible resource allocation, and stringent time synchronization requirements. Therefore, there is an urgent need in this field for an innovative solution that can deeply couple routing mechanisms with multiple access technologies to fully leverage the technological potential of UWB and build an efficient, reliable, and highly adaptable wireless ad hoc network. Summary of the Invention

[0007] In view of this, the present invention aims to propose a method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV, and an ad hoc network node device, in order to solve the problem of high data transmission failure rate and difficulty in meeting real-time communication requirements in existing UWB ad hoc networks.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV, the method comprising: an initialization step: configuring network parameters, including the number of nodes N, time slot length T, and guard time. and the number of data subframes per cycle The time frame division and allocation steps are as follows: The communication cycle is divided into synchronization frames, routing frames, and at least one data subframe. Communication time slots are allocated to each node in the network based on the TDMA protocol. The synchronization frame occupies a fixed time slot for time synchronization, the routing frame allocates a unique time slot to each node for broadcasting routing information, and the data subframe allocates time slots to each node in a round-robin manner for data transmission. The time synchronization step involves the designated node broadcasting a synchronization packet containing a timestamp of the cycle start point within the synchronization frame. Other nodes receive the synchronization packet and calibrate their local clocks accordingly to achieve network-wide time synchronization. The routing information exchange step involves each node broadcasting its DSDV routing table within the allocated time slot within the routing frame. Neighboring nodes receive the broadcast and update their own routing tables based on the sequence number and hop count. The data transmission step involves each node transmitting data within the allocated time slot based on the updated routing table, and employing a verification mechanism to ensure data integrity.

[0009] Furthermore, a preferred method is proposed, wherein the time synchronization step specifically includes: the sending node broadcasting a synchronization packet in the allocated synchronization time slot, the synchronization packet carrying its calculated period start timestamp. After receiving the synchronization packet, the receiving node uses its local time at the time of reception. and relative offset within the period Calculate the self-estimated cycle starting point: ; Calculate time error: The local clock offset is updated based on the time error e and the preset correction coefficient K, so that the cycle start point of all nodes tends to be consistent.

[0010] Furthermore, a preferred method is proposed, wherein the formula for calculating the relative offset τ(t) within the period is:

[0011] in, The total duration of the communication cycle. This is the starting point of the current maintenance cycle for the node. This represents the modulo operation.

[0012] Furthermore, a preferred approach is proposed, wherein the routing information exchange step includes the following routing table update mechanism: if the destination node in the received routing table entry is a node that does not exist in the routing table of this node, then the entry is added, and the next hop is set to the neighboring node that sent the routing table, and the hop count is set to the received hop count plus one; if the sequence number in the received routing table entry is greater than the sequence number of the corresponding destination node in this routing table, or the sequence number is the same but the hop count is smaller, then the corresponding entry in this routing table is updated; a lifespan is set for each routing table entry, and the lifespan of non-self routing entries is decremented after each routing frame, and the entry is deleted when the lifespan drops to zero.

[0013] Furthermore, a preferred method is proposed, wherein the total duration of the communication cycle is... Determined by the following formula:

[0014] in, The time slot length, To protect time, N is the number of time slots occupied by the routing frame. This represents the total number of time slots occupied by all data subframes.

[0015] Furthermore, a preferred method is proposed, wherein the time slot allocation rule within the data subframe is as follows: for the i-th time slot in the k-th data subframe, its transmitting node number is determined by the following formula: .

[0016] Based on the same inventive concept, this invention also proposes an ultra-wideband wireless ad hoc network node device, which is implemented based on any of the methods described above. The device includes: an ultra-wideband communication module for transmitting and receiving pulse signals; a storage module for storing network parameters, a DSDV routing table, and program instructions; and a processing module coupled to the ultra-wideband communication module and the storage module, configured to execute the program instructions to complete the steps of time frame division and allocation, time synchronization, routing information exchange, and data transmission.

[0017] Furthermore, a preferred method is proposed, wherein when the processing module runs the time synchronization algorithm, it is configured to: when acting as a sending node, calculate and encapsulate the period start timestamp into the synchronization packet; when acting as a receiving node, parse the received synchronization packet, calculate the time error, and update the local clock parameters using a filtering method.

[0018] The present invention also proposes a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes an ultra-wideband wireless ad hoc network construction method based on TDMA and DSDV as described in any of the preceding claims.

[0019] The present invention also proposes a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of a method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV as described in any of the above-mentioned embodiments.

[0020] Compared with existing technologies, the advantages of this invention are as follows: Traditional DSDV protocols require nodes to periodically broadcast their routing tables across the entire network, which generates significant control overhead in highly dynamic UWB ad hoc networks, crowding out already scarce wireless resources. Simultaneously, its route updates are lagging, making it difficult to respond to topology changes in real time, resulting in outdated path information and a high data transmission failure rate. This invention utilizes a TDMA frame structure to establish a dedicated, collision-free broadcast channel (i.e., routing frame NET) for routing information exchange. Each node broadcasts its DSDV routing table within a pre-allocated, unique time slot, fundamentally avoiding collisions between routing packets. This timed, fixed-point broadcast mechanism transforms the originally random, contentious, and conflict-prone routing update process into an ordered, predictable, and low-overhead operation. The effect is that while ensuring the network-wide dissemination of routing information, it significantly reduces control overhead and, leveraging the temporal determinism of TDMA, accelerates route convergence, enabling the network to adapt to topology changes more quickly, thereby improving overall communication efficiency and stability.

[0021] Traditional TDMA employs static or semi-static time slot allocation. In UWB networks with high node density and fluctuating traffic, this leads to uneven time slot allocation, with some nodes experiencing time slot shortages while others remain idle, resulting in low time slot utilization efficiency and high communication latency. Furthermore, network-wide time synchronization is a significant challenge, as synchronization errors can easily cause time slot overlap and data collisions. This invention designs a dynamic round-robin time slot allocation algorithm. In the data subframe (DATA), the allocation rules for speaking nodes ensure that each node receives a fair rotation of data transmission opportunities in different cycles. This design achieves dynamic reuse and load balancing of time slot resources, effectively avoiding the problem of some nodes being "starved" for extended periods, and is particularly suitable for scenarios with sudden changes in node data traffic. Simultaneously, this invention proposes an innovative distributed time synchronization algorithm. In the synchronization frame (SYNC) at the beginning of each communication cycle, a designated node broadcasts a synchronization packet carrying a precise timestamp, and other nodes progressively correct their local clocks by calculating errors and using filtering methods. This mechanism ensures that all network nodes maintain high-precision time synchronization at the sub-slot level under TDMA scheduling, laying a solid foundation for conflict-free slot access and significantly reducing the probability of data packet collisions caused by synchronization errors.

[0022] In existing technologies, routing protocols (such as DSDV) and media access control protocols (such as TDMA) are typically designed and operated independently, lacking coordination and struggling to cope with large-scale network expansion. The core of this invention lies in integrating route maintenance (DSDV) and channel access (TDMA) into a unified scheduling framework. Routing frames (NET) and data frames (DATA) alternate in time; the updating of routing information provides real-time and reliable routing guidance for data transmission, while the collision-free channel of TDMA ensures reliable flooding of routing information. The two complement each other. Furthermore, the life-to-life (LIFE) mechanism introduced into the routing table, combined with periodic decrementing and failure cleanup of routing frames, achieves automated, low-overhead maintenance of failed links. This collaborative design enables the network to automatically adapt to the addition and removal of nodes, maintaining good connectivity, thereby significantly enhancing the network's scalability and long-term operational reliability in large-scale, highly dynamic environments. Attached Figure Description

[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 is a flowchart of an ultra-wideband wireless ad hoc network construction method based on TDMA and DSDV according to the present invention; Figure 2 is a schematic diagram of the working timing of each node after time frame division according to the present invention; Figure 3 is a schematic diagram of the system timing after time synchronization according to the present invention; Figure 4 is a schematic diagram of the routing table format designed in the case of 20 nodes according to the present invention. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other, and the described embodiments are only some embodiments of the present invention, not all embodiments.

[0025] Implementation Method 1: This implementation method addresses the problems of high routing update overhead, high latency, inflexible resource allocation, and stringent time synchronization requirements faced by UWB ad hoc networks in highly dynamic and high-density scenarios. It proposes a method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV. The method includes: an initialization step: configuring network parameters, including the number of nodes N, time slot length T, guard time Tg, and the number of data subframes per cycle Ndata; and a time frame division and allocation step: dividing the communication cycle into synchronization frames, routing frames, and at least one data subframe, and allocating data subframes based on the TDMA protocol. In this network, each node is allocated a communication time slot. The synchronization frame occupies a fixed time slot for time synchronization, the routing frame allocates a unique time slot for each node to broadcast routing information, and the data subframe allocates time slots to each node in a round-robin fashion for data transmission. The time synchronization steps are as follows: within the synchronization frame, a designated node broadcasts a synchronization packet containing a period start timestamp. The remaining nodes receive the synchronization packet and calibrate their local clocks accordingly to achieve network-wide time synchronization. Specifically, in this embodiment, the time synchronization steps include: the sending node broadcasts a synchronization packet in its allocated synchronization time slot, the synchronization packet carrying its calculated period start timestamp. After receiving the synchronization packet, the receiving node uses its local time at the time of reception. and relative offset within the period Calculate the self-estimated cycle starting point: ; Calculate time error: The local clock offset is updated based on the time error e and the preset correction coefficient K to make the cycle starting point of all nodes consistent. In this embodiment, the formula for calculating the relative offset τ(t) within the cycle is:

[0026] in, The total duration of the communication cycle. This is the starting point of the current maintenance cycle for the node. The modulo operation represents the remainder after dividing two integers; the total communication cycle duration described in this embodiment. Determined by the following formula:

[0027] in, The time slot length, To protect time, N is the number of time slots occupied by the routing frame. The total number of time slots occupied by all data subframes; Routing information exchange steps: Within the routing frame, each node broadcasts its DSDV routing table in the allocated time slot, and neighboring nodes receive and update their own routing tables according to the sequence number and hop count; In the routing information exchange steps described in this embodiment, the routing table update mechanism includes: if the destination node in the received routing table entry is a node that does not exist in the routing table of this node, then add the entry, set the next hop to the neighboring node that sent the routing table, and set the hop count to the received hop count plus one; if the sequence number in the received routing table entry is greater than the corresponding number in the routing table of this node... If the sequence number of the destination node is the same, or the sequence number is the same but the hop count is smaller, then the corresponding entry in this routing table is updated; a lifetime is set for each routing table entry, and the lifetime of non-self routing entries is decremented after each routing frame. When the lifetime drops to zero, the entry is deleted; Data transmission steps: Within the data subframe, each node transmits data based on the updated routing table in the allocated time slot, and a verification mechanism is used to ensure data integrity; In this embodiment, the time slot allocation rule within the data subframe is as follows: For the i-th time slot in the k-th data subframe, its sending node number is determined by the following formula: .

[0028] Implementation Method 2: Refer to Figures 1 to 4 for an explanation of this implementation method. This implementation method provides a complete embodiment of the ultra-wideband wireless ad hoc network construction method based on TDMA and DSDV described in Implementation Method 1. The specific process includes: The wireless ad hoc network nodes in this implementation method use a UWB development board based on the OST-U1011 chip developed by OSMicro, which has reliable and stable performance.

[0029] Step 1: Initialization When the system starts, the following initialization work needs to be completed first to determine the network parameters of the entire self-organizing network: (1) Initialize the scheduler. The scheduler includes the node number, node capacity, number of data cycles in each round, length of a single time slot, and protection time, which are used to define the basic parameters of the network. Among them, the node number assigns a unique identifier to each node to ensure that each node in the network can recognize each other; the node capacity defines the maximum number of nodes that can be accommodated in the entire network; the number of data cycles in each round defines how many time periods can be used to send and receive data for a single node in each communication cycle, and generally also limits the upper limit of nodes that a single node can perform data communication at the same time in a communication cycle; the length of a single time slot determines the duration of each time slot to ensure stable data transmission; the protection time refers to leaving a certain amount of time between time slots to avoid interference between time slots.

[0030] (2) Initialize the global state controller. The global state controller is used to control the transmission of various types of data in the entire system and avoid interference between nodes. The most important parameters in the global state controller are three: time frame type, the role of this node in the current time frame, and the speaker in this time frame. The time frame type includes time synchronization frame SYNC, routing frame NET, and data frame DATA, which are used to indicate the events that should be executed in the current time frame; the role of this node in the current time frame indicates whether this node should perform the send TX or receive RX in the current data frame; the speaker in this time frame is which node should perform the send or receive event in the current time frame.

[0031] Step 2: Time Frame Division and Time Slot Allocation In this embodiment, time frames are divided and time slots are allocated based on the TDMA protocol. This step divides the time into multiple time slots and allocates these slots to different communication nodes according to each node's communication needs and network status. This ensures that each node can exclusively occupy the channel within a specified time period, thereby avoiding channel conflicts and interference between nodes.

[0032] First, the entire communication cycle is divided into several time frames, each containing multiple time slots. Each time frame indicates a different communication stage, such as synchronization, routing, or data transmission. Time frames can be categorized into synchronization frames (SYNC), routing frames (NET), and data frames (DATA), each performing its corresponding function. Then, within each time frame, each data frame is divided into different time slots based on the number of nodes in the network. These time slots are allocated to each node in the network, and each node determines its working state by checking if its assigned time slot is the one allocated to it. The pseudocode for the time frame division and time slot allocation algorithm in this embodiment is shown in Table 1.

[0033] Table 1. Pseudocode of Time Frame Division and Time Slot Allocation Algorithm

[0034] After obtaining network parameters during system initialization, the algorithm first calculates the total duration of the communication cycle and divides one cycle into synchronization frames (SYNC), routing frames (NET), and several data subframes (DATA) according to TDMA. The total duration of the cycle is:

[0035] Let the number of nodes be The number of data subframes per cycle is The time slot length is The protection time is If SYNC occupies 2 time slots and NET occupies 2 time slots Each time slot, each DATA subframe occupies If there are multiple time slots, the total duration of the period can be expressed as:

[0036] Subsequently, the SYNC frame specifies the time slots occupied by the primary and backup nodes to send synchronization information. In the NET frame, a unique time slot is allocated to each node according to its node number for routing table broadcasting. In the DATA subframe, a round-robin method is used to allocate time slots to each node to achieve fair data transmission and reception.

[0037] in For the first DATA subframe index, This is the time slot index within the subframe.

[0038] At runtime, the system locates the specific frame and time slot based on the relative offset between the current time and the cycle start point ts. The global state controller then outputs the current frame type, the current time slot speaker, and the TX / RX role that this node should perform, enabling conflict-free communication among all nodes according to the same scheduling rules.

[0039] After time frame division and time slot allocation, the working timing of each node in the network is shown in Figure 2.

[0040] Step 3: Time Synchronization. After Step 2, the time of all nodes in the system has been divided into different time frames. Each time frame is further divided into different time slots based on the number of nodes, and these time slots are allocated to different nodes. However, the startup and network access times of each node are not consistent, resulting in different starting points for their timelines. Therefore, each node's system time is not the same at any given time. TDMA requires all nodes in the system to maintain the same and consistent time so that each node can perform the same task within a certain time period, ensuring normal information exchange between nodes.

[0041] This implementation involves a new time synchronization algorithm, the pseudocode of which is shown in Table 2.

[0042] Table 2. Pseudocode of Time Synchronization Algorithm

[0043] The algorithm completes time synchronization within the SYNC frame of each communication cycle. The system uses a global state controller to determine the current SYNC frame and the speaker in the current time slot, thereby enabling the primary / backup nodes to broadcast the cycle start timestamp in their respective SYNC time slots. The synchronization packet is received by other nodes in the SYNC time slot, and they calculate their own estimated period starting point as follows:

[0044] in, It is the local unified time at the moment of reception (after software correction). The relative time within the period of that moment is calculated using the following formula:

[0045] After a node obtains its own periodic starting point, it can then calculate the relationship with... Error:

[0046] Then, the local clock offset is updated in a step / filtering manner (or ts is directly corrected) so that all nodes gradually converge to a consistent cycle starting point ts:

[0047] in, This is the clock correction amount. This is the correction factor.

[0048] When a synchronization packet is lost, the node retains the previous correction result and waits for the next round of SYNC frames to correct again, so as to ensure that TDMA scheduling maintains time consistency across the entire network.

[0049] After the time synchronization algorithm, the working time sequence of each node in the network is shown in Figure 3. Here, ts represents the unified working start time of all nodes in the system after time synchronization.

[0050] Step 4: Routing Information Exchange In the DSDV routing protocol, the entries in the routing table usually include the following key fields: (1) Destination Address: The address of the destination node recorded in the routing table.

[0051] (2) Next Hop Address: The address of the next relay node from the source node to the destination node, i.e. the route specified in the routing table.

[0052] (3) Hop Count: The number of hops required to reach the target address, representing the distance from the source node to the destination node.

[0053] (4) Sequence Number: The sequence number of the destination node, which helps to distinguish different routing information and ensures the timeliness and freshness of routing information. Routing information with a larger sequence number usually indicates a more recent route.

[0054] (5) Update Time Stamp: This indicates the time when the routing table entry was last updated. This helps the routing algorithm determine whether expired or no longer valid routing information needs to be refreshed.

[0055] (6) Valid Flag: Indicates whether the route entry is valid. Sometimes it is used to indicate whether the route needs to be recalculated or updated.

[0056] In the DSDV protocol, nodes periodically broadcast their routing updates to ensure that every node in the network maintains an up-to-date routing table. Using sequence numbers, nodes can determine the age of routing information and avoid using outdated information.

[0057] Following the general format of routing tables in the DSDV protocol, in this invention, each node periodically or when a route changes will broadcast its stored routing table to its neighboring nodes in the routing frame. The neighboring nodes will compare the received routing table with their own stored routing table. If the received routing table information differs from their own stored routing table, they will update their routing table according to the algorithm. The pseudocode of the algorithm is shown in Table 3.

[0058] Table 3. Pseudocode for DSDV Routing Table Update Algorithm

[0059] This algorithm performs route maintenance only within the routing frame NET. The routing table uses the actual format {DEST, NEXT, HOPS, LIFE, FLAGS}, where FLAGS="*" is only used to identify self-routes (i.e., DEST=this node ID, NEXT=this node ID, HOPS=0). When the global state controller SLOT_INFO_T determines that the current frame is NET, if the local node's role is transmit (TX), it broadcasts the local routing table in the allocated NET time slot; if the role is receive (RX), it receives neighbor broadcast packets and processes each routing entry: for each destination node DEST, it uses the neighbor as a candidate next hop NEXT and updates the hop count to the neighbor's hop count plus one. If the candidate path is shorter or the destination route does not exist locally, it writes / updates the corresponding entry and refreshes its LIFE to the maximum value; if the update conditions are not met, it only refreshes the LIFE of the entry. The system then performs failure handling: except for self-routing, the LIFE of each routing entry is decremented after each round of NET. When the LIFE of a routing entry is reduced to 0, the destination link is directly deleted from the routing table, thereby realizing automatic cleanup and maintenance of dynamic links.

[0060] The routing table designed in this embodiment is shown in Figure 4.

[0061] Step 5: Data Transmission and Verification After completing system initialization, time frame division and time slot allocation, time synchronization, and routing information exchange, the next crucial step is to ensure stable data transmission within the wireless ad hoc network and to guarantee data accuracy and integrity through a verification mechanism. To achieve this, the system employs the TDMA protocol to allocate time slots, with each node exclusively occupying the channel for data transmission within its designated time slot. This approach effectively avoids channel conflicts and interference between nodes, thereby improving network communication efficiency.

[0062] During data transmission, a CRC (Cyclic Redundancy Check) mechanism is used to detect transmission errors and ensure data accuracy. Each data frame is accompanied by a CRC checksum. Upon receiving data, the receiving node calculates and compares the checksum to verify the data's integrity. If the data passes the checksum verification, the receiving node continues processing it; if the verification fails, the receiving node sends a retransmission request to ensure data integrity.

[0063] Furthermore, this implementation introduces an ACK / NACK mechanism to further confirm successful data reception. When the receiving node successfully receives the data and completes the verification, it sends an ACK frame to the sending node, indicating that the data is error-free. If the verification fails, the receiving node sends a NACK frame, requesting the sending node to retransmit the data. Through this mechanism, the system can automatically retransmit in the event of data loss or transmission errors, thereby ensuring the reliability of data transmission.

[0064] To prevent data loss or out-of-order delivery, we also added a timestamp and sequence number to each data frame. The timestamp marks the time the data was sent, ensuring timely transmission, while the sequence number helps the receiving node determine the order of data frames. By checking the sequence number, the receiving node ensures that the received data arrived in the correct order, avoiding packet loss or out-of-order delivery.

[0065] The method proposed in this embodiment ensures high reliability and accuracy of data transmission by employing time slot allocation, CRC check, ACK / NACK confirmation mechanism and timestamp management, thus fully guaranteeing the stable and secure transmission of data in wireless ad hoc networks.

[0066] The method proposed in this embodiment combines the DSDV routing protocol with the TDMA time slot allocation mechanism, providing a highly efficient wireless ad hoc network solution. By achieving stable route maintenance through the DSDV routing protocol and combining it with TDMA for time slot allocation, channel conflicts and latency are effectively avoided, improving network transmission efficiency and throughput. This combined approach can resolve high-frequency topology changes and time slot conflicts, enhancing the performance of UWB wireless ad hoc networks in complex environments.

[0067] The method proposed in this implementation optimizes the routing table update mechanism in the DSDV routing protocol. By incorporating a sequence number mechanism, a node will only update its routing table when the received new routing information has a large sequence number or a small hop count, thereby reducing unnecessary update operations. Furthermore, by utilizing the TDMA time slot mechanism, data routing updates can be performed within non-conflicting time slots, thus improving network response speed and overall efficiency.

[0068] This embodiment proposes a novel time slot allocation and time synchronization mechanism. The communication cycle is divided into multiple time slots using the TDMA protocol, and these slots are allocated rationally based on the number of nodes in the network. Each node transmits data within its designated time slot, avoiding channel conflicts. Furthermore, this embodiment proposes a time synchronization algorithm to ensure that the clocks of all nodes in the network remain consistent, thereby guaranteeing synchronization and coordination during data transmission and ensuring efficient data transmission and reception.

[0069] Implementation Method 3: This implementation method proposes an ultra-wideband wireless ad hoc network node device. The device is implemented based on the method described in Implementation Method 1 or Implementation Method 2. The device includes: an ultra-wideband communication module for sending and receiving pulse signals; a storage module for storing network parameters, DSDV routing tables, and program instructions; and a processing module coupled to the ultra-wideband communication module and the storage module, configured to execute the program instructions to complete time frame division and allocation, time synchronization, routing information exchange, and data transmission steps.

[0070] In this embodiment, the processing module is configured to: when acting as a sending node, calculate and encapsulate the period start timestamp into a synchronization packet; when acting as a receiving node, parse the received synchronization packet, calculate the time error, and update the local clock parameters using a filtering method.

[0071] Implementation Method 4: This implementation method proposes a computer device, including a memory and a processor. The memory stores a computer program. When the processor runs the computer program stored in the memory, the processor executes an ultra-wideband wireless ad hoc network construction method based on TDMA and DSDV as described in Implementation Method 1 or Implementation Method 2.

[0072] Implementation Method 5: This implementation method proposes a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of an ultra-wideband wireless ad hoc network construction method based on TDMA and DSDV as described in either Implementation Method 1 or Implementation Method 2.

[0073] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, systems, or computer program products. Therefore, this disclosure can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this disclosure can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0074] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more flowchart illustrations and / or one or more block diagrams. These computer program instructions may also be stored in a computer-readable storage medium capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in one or more flowchart illustrations and / or one or more block diagrams.

[0075] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowcharts and / or one or more block diagrams.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and not to limit its protection scope. Although this disclosure has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this disclosure, they can still make various changes, modifications or equivalent substitutions to the specific implementation of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the published pending claims.

Claims

1. A method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV, characterized in that, The method includes: an initialization step: configuring network parameters, including the number of nodes N, time slot length T, and protection time. and the number of data subframes per cycle The time frame division and allocation steps are as follows: The communication cycle is divided into synchronization frames, routing frames, and at least one data subframe. Communication time slots are allocated to each node in the network based on the TDMA protocol. The synchronization frame occupies a fixed time slot for time synchronization, the routing frame allocates a unique time slot to each node for broadcasting routing information, and the data subframe allocates time slots to each node in a round-robin manner for data transmission. The time synchronization step involves the designated node broadcasting a synchronization packet containing a timestamp of the cycle start point within the synchronization frame. Other nodes receive the synchronization packet and calibrate their local clocks accordingly to achieve network-wide time synchronization. The routing information exchange step involves each node broadcasting its DSDV routing table within the allocated time slot within the routing frame. Neighboring nodes receive the broadcast and update their own routing tables based on the sequence number and hop count. The data transmission step involves each node transmitting data within the allocated time slot based on the updated routing table, and employing a verification mechanism to ensure data integrity.

2. The method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV according to claim 1, characterized in that, The time synchronization step specifically includes: the sending node broadcasting a synchronization packet in the allocated synchronization time slot, the synchronization packet carrying its calculated period start timestamp. After receiving the synchronization packet, the receiving node uses its local time at the time of reception. and relative offset within the period Calculate the self-estimated cycle starting point: ; Calculate time error: The local clock offset is updated based on the time error e and the preset correction coefficient K, so that the cycle start point of all nodes tends to be consistent.

3. The method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV according to claim 2, characterized in that, The formula for calculating the relative offset τ(t) within the period is: in, The total duration of the communication cycle. This is the starting point of the current maintenance cycle for the node. This represents the modulo operation.

4. The method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV according to claim 1, characterized in that, In the routing information exchange step, the routing table update mechanism includes: if the destination node in the received routing table entry is a node that does not exist in the routing table of this node, then add the entry and set the next hop to the neighboring node that sent the routing table, and set the hop count to the received hop count plus one; if the sequence number in the received routing table entry is greater than the sequence number of the corresponding destination node in this routing table, or the sequence number is the same but the hop count is smaller, then update the corresponding entry in this routing table; set a lifetime for each routing table entry, and decrement the lifetime of non-self routing entries after each routing frame, and delete the entry when the lifetime drops to zero.

5. The method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV according to claim 3, characterized in that, The total duration of the communication cycle Determined by the following formula: in, The time slot length, To protect time, N is the number of time slots occupied by the routing frame. This represents the total number of time slots occupied by all data subframes.

6. The method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV according to claim 5, characterized in that, The time slot allocation rule within the data subframe is as follows: For the i-th time slot in the k-th data subframe, its transmitting node number is determined by the following formula: 。 7. A broadband wireless self-organizing network node device, characterized in that, The device is implemented based on the method of any one of claims 1 to 6, and the device includes: an ultra-wideband communication module for sending and receiving pulse signals; a storage module for storing the network parameters, DSDV routing table and program instructions; and a processing module coupled to the ultra-wideband communication module and the storage module, and configured to execute the program instructions to complete the steps of time frame division and allocation, time synchronization, routing information exchange and data transmission.

8. The ultra-wideband wireless self-organizing network node device according to claim 7, characterized in that, When running the time synchronization algorithm, the processing module is configured to: when acting as a sending node, calculate and encapsulate the period start timestamp into the synchronization packet; when acting as a receiving node, parse the received synchronization packet, calculate the time error, and update the local clock parameters using a filtering method.

9. A computer device, characterized in that: It includes a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes a method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV as described in any one of claims 1-6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of a method for constructing an ultra-wideband wireless ad hoc network based on TDMA and DSDV as described in any one of claims 1-6.

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