阅读说明：本技术 一种保障高优先级时敏业务可靠传输的自组织网络 (Self-organizing network for guaranteeing reliable transmission of high-priority time-sensitive service ) 是由 郎修璞 孙士勇 归琳 朱世超 俞晖 于 2021-09-02 设计创作，主要内容包括：本发明涉及一种保障高优先级时敏业务可靠传输的自组织网络,包括若干自组织网络节点,存储有自组织网络接入协议程序,实现以下步骤：S1、自组织网络节点构建无线通信MAC层时帧；S2、有通信需求的自组织网络节点加载传输负载；S3、加载传输负载的自组织网络节点根据业务的优先级随机选择退避窗口长度；S4、传输时隙竞争自组织网络节点采用退避窗口机制发送传输竞争声明,通过业务传输时隙时帧竞争裁定机制确定传输时隙竞争自组织网络节点的业务传输时隙数值；S5、自组织网络节点在对应数值的业务传时隙发送传输负载。有益效果是保障高优先级时敏业务可靠传输、同时不影响其他业务传输性能。(The invention relates to a self-organizing network for guaranteeing reliable transmission of time-sensitive services with high priority, which comprises a plurality of self-organizing network nodes and a self-organizing network access protocol program, and realizes the following steps: s1, the self-organizing network node constructs a wireless communication MAC layer time frame; s2, loading a transmission load by the self-organizing network node with the communication requirement; s3, the self-organizing network node loading the transmission load randomly selects the length of the backoff window according to the priority of the service; s4, the transmission time slot competition self-organizing network node sends a transmission competition statement by adopting a backoff window mechanism, and determines the service transmission time slot value of the transmission time slot competition self-organizing network node through a service transmission time slot time frame competition arbitration mechanism; and S5, the self-organizing network node sends the transmission load in the service transmission time slot corresponding to the value. The method has the advantages of ensuring the reliable transmission of the time-sensitive service with high priority and simultaneously not influencing the transmission performance of other services.)

1. A self-organizing network for guaranteeing reliable transmission of time-sensitive services with high priority comprises a plurality of self-organizing network nodes, wherein the self-organizing network nodes communicate through a wireless communication network; the ad-hoc network node comprising a processor, a memory, and a wireless communication interface for wireless communication, characterized in that: the memory is stored with a self-organizing network access protocol program, a countdown counter for recording the length of a backoff window, a high-priority time-sensitive service queue for storing high-priority time-sensitive service data and other low-priority service queues for storing other low-priority service data; the self-organizing network node processor is controlled by a self-organizing network access protocol program to realize the following steps:

s1, the self-organizing network node constructs a wireless communication MAC layer time frame, and the length of the single wireless communication MAC layer time frame is t_frame＝t_demandWherein t is_demandThe method is a requirement of single-hop time delay of high-priority time-sensitive service, the length of a time frame of a single wireless communication MAC layer comprises K time slots, and the length of a single time slot is t_slot＝t_frameThe 1 st time slot is a contention time slot, the 2 nd to the K th time slots are service transmission time slots and are marked as the 1 st service transmission time slot to the K-1 st service transmission time slot, the contention time slot comprises M contention sub-time slots according to the shortest physical frame length supported by the self-organizing network node, M, K is a positive integer, M is a positive integer>K-1；

S2, loading a transmission load by the self-organizing network node with the communication requirement, firstly, taking the first data from the high-priority queue, and if the time-sensitive service queue with the high priority is empty, reading the data from other low-priority service queues;

s3, the self-organizing network node loading the transmission load randomly selects the length of a backoff window according to the priority of the service and records the length of the backoff window in a countdown timer, the length of the backoff window randomly selected by the high-priority time-sensitive service is small, the length of the backoff window randomly selected by other low-priority services is large, and the length interval of the backoff window randomly selected by the high-priority time-sensitive service is not overlapped with the length interval of the backoff window randomly selected by other low-priority services;

s4, randomly selecting the self-organizing network node with the length of the backoff window as a transmission time slot competition self-organizing network node, in a new wireless communication MAC layer time frame competition time slot stage, after each competition sub-time slot, subtracting 1 from a countdown counter of the transmission competition self-organizing network node with the value larger than 0, simultaneously immediately sending a transmission competition statement by the transmission time slot competition self-organizing network node with the countdown counter value of 0 through a wireless network, if collision is detected, giving up transmission by the transmission time slot competition self-organizing network node with the countdown counter value of 0 and continuously competing for a service transmission time slot in the next wireless communication MAC layer time frame, and if collision is not detected, determining the service transmission time slot value of the transmission time slot competition self-organizing network node by the self-organizing network node through a service transmission time slot time frame competition arbitration mechanism;

s5, in the wireless communication MAC layer time frame service transmission time slot stage, the self-organizing network node which obtains the service transmission time slot sends the transmission load loaded in the step S2 in the service transmission time slot with the corresponding value through the wireless network.

2. The ad-hoc network for guaranteeing reliable transmission of the high-priority time-sensitive service according to claim 1, wherein: the self-organizing network node also comprises an available transmission time slot counter used for recording the value of the service transmission time slot, and a tone level transceiver used for sending and receiving and analyzing high-level tone signals through a wireless communication interface, and the self-organizing network node processor controlled by a self-organizing network access protocol program further realizes the following steps:

step S1, the shortest physical frame length supported by the self-organizing network node is t_hwWherein t is_hw＜t_slotThen the contention slot is further divided intoOne contention sub-slot, t_slot-M_cptt_hwA guard interval between a contention time slot and a service transmission time slot;

step S3, initializing the available transmission time slot counter of the self-organizing network node loaded with the transmission load to K-1;

step S4, the frame competition arbitration mechanism of the service transmission timeslot means that, every time a competition sub-timeslot passes, a transmission timeslot competition self-organizing network node with a countdown counter value of 0 immediately sends a high-level tone signal as a transmission competition statement through the wireless network, and if the transmission timeslot competition self-organizing network node with the countdown counter value greater than 0 monitors the high-level tone signal through the wireless network, the transmission timeslot competition self-organizing network node with the countdown counter value greater than 0 can use the transmission timeslot counter to be decreased by 1; through M_cptAfter each contention sub-slot, the transmission slot contends for the self-organizing network node to determine that the service transmission slot value is K minus the available transmission slot counter value, the transmission slot contending for the self-organizing network node with the available transmission slot counter value being 0 gives up transmission and continuously contends for the service transmission slot in the next wireless communication MAC layer time frame.

3. The ad-hoc network for guaranteeing reliable transmission of the high-priority time-sensitive service according to claim 2, wherein: the self-organizing network high-priority time-sensitive service single-hop delay requirement t_demandThe frame length of the single wireless communication MAC layer time frame is 2ms, the frame length of the single wireless communication MAC layer time frame comprises 4 time slots with the length of 0.5ms, the shortest physical frame length supported by the self-organizing network node is 60us, the competition time slot is further divided into 8 competition sub time slots, and 20us is a protection interval between the competition time slot and the service transmission time slot.

4. The ad-hoc network for guaranteeing reliable transmission of the high-priority time-sensitive service according to claim 1, wherein: the self-organizing network node processor is a processor with the capabilities of analyzing data packets in a short time and rapidly receiving and transmitting, and is controlled by a self-organizing network access protocol program to further realize the following steps:

step S1, the shortest physical frame length supported by the self-organizing network node is t_hwWherein t is_hw＜t_slotThen the contention slot is further divided intoSub-slots of 1 to M_cpt-1 sub-slot is a contention sub-slot, Mth_cptSub-slot plus guard interval duration t_slot-M_cptt_hwIs a reserved broadcast sub-slot;

step S4, the frame competition arbitration mechanism of the service transmission timeslot means that, each time a competition sub-timeslot passes, a transmission timeslot competition self-organized network node with a counter value of 0 when counting down immediately sends the ID number of the node through the wireless network as a transmission competition statement, the first transmission timeslot competition self-organized network node that sends the ID number of the node through the wireless network in the competition sub-timeslot and does not detect a collision is a master node, and the master node is responsible for monitoring the node ID number sent by the transmission timeslot competition self-organized network node through the wireless network; through M_cptAfter 1 competition sub-time slot, the main node determines the service transmission time slot value of the transmission time slot competition self-organizing network node according to the sequence of the monitored node ID numbers through analysis, and sends a reserved broadcast subframe in the reserved broadcast sub-time slot to inform other transmission time slot competition self-organizing network nodes, and the transmission time slot competition self-organizing network node which does not obtain the service transmission time slot abandons transmission and continues to compete for the service transmission time slot in the next wireless communication MAC layer time frame.

5. The ad-hoc network for guaranteeing reliable transmission of the high-priority time-sensitive service according to claim 4, wherein: the self-organizing network high-priority time-sensitive service single-hop delay requirement t_demandThe frame length of the single wireless communication MAC layer time frame is 2ms, the frame length of the single wireless communication MAC layer time frame comprises 4 time slots with the length of 0.5ms, the shortest physical frame length supported by the self-organizing network node is 60us, and the competition time slot is further divided into 7 competition sub-time slots and 1 reserved broadcast sub-time slot.

6. An ad-hoc network for guaranteeing reliable transmission of high priority time sensitive services according to any one of claims 1 to 5, characterised in that: the self-organizing network node is an unmanned aerial vehicle self-organizing network node.

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of wireless communication, in particular to a self-organizing network for ensuring reliable transmission of high-priority time-sensitive services.

[ background of the invention ]

Ad-hoc networks (ad-hoc networks) are a decentralized communication network consisting of peer nodes which act both as service senders and as service forwarders. The self-organizing network generally consists of dynamic mobile nodes such as airplanes, unmanned planes, automobiles, ships and the like. Therefore, the continuous change of the self-organizing network topology caused by the high dynamic of the nodes makes the realization of reliable and stable wireless communication become a complicated technical problem. The data link layer in the OSI seven-layer protocol is divided into an upper layer LLC (logical link control) and a lower layer MAC (medium access control), the MAC layer is mainly responsible for controlling and connecting the physical medium of the physical layer; when sending data, the MAC protocol can judge whether the data can be sent in advance, if so, the MAC protocol adds some control information to the data, and finally sends the data and the control information to a physical layer in a specified format; when receiving data, the MAC protocol first determines whether an input message has a transmission error, and if there is no error, removes the control message and sends it to the LLC (logical link control) layer.

The access protocol design is one of the important technical means for solving the communication problem of the self-organizing network. The access protocol defines a set of rules for sharing channels by network nodes, and the rules can be divided into three types according to different channel resource use modes: time Division Multiple Access (TDMA) based reservation, carrier sense multiple access/collision avoidance (CSMA/CA) based contention, and multiple access based traffic priority-based Statistics (SPMA). In the TDMA protocol, nodes to be transmitted coordinate and reserve time slots through an RTS/CTS mechanism, so that no collision of data packets occurs during transmission among the nodes. The RTS/CTS mechanism means that the sender sends an RTS frame before data transmission, the receiver sends a CTS frame after receiving the RTS frame, and surrounding devices which hear the RTS and CTS frames temporarily do not use the channel for transmission so as to avoid interference. However, the coordination and reservation of time slots will introduce significant delays in transmission and greatly reduce the effective bandwidth of the network. CSMA/CA removes the slot reservation mechanism, so that the time delay is obviously improved in a light load network. However, while CSMA/CA employs a back-off window mechanism to reduce collisions when packets are transmitted on a shared channel, CSMA/CA does not guarantee reliable transmission of traffic. The back-off window mechanism is that if collision occurs with other stations during transmission, a back-off algorithm is used to back off for a random time, and then data is retransmitted. The SPMA can guarantee low-delay transmission with high priority and reliable transmission of all services in the network, however, the hardware implementation difficulty of the SPMA poses a great challenge to the feasibility of the protocol.

A single tone signal is a pure sinusoidal signal of a single frequency.

Reliable transmission of time sensitive traffic has important practical requirements. The TTNT (Tactical target Network Technology) data link system in the united states suggests that the time-sensitive traffic single-hop transmission delay in an ad hoc Network needs to be less than 2 ms. According to the analysis, the TDMA protocol has poor time delay performance, and the CSMA cannot be used as an implementation mode of time-sensitive service transmission of the self-organizing network because reliable transmission cannot be guaranteed. For an ad hoc network which does not depend on an infrastructure, the mode of the SPMA asynchronous duplex communication is difficult to support by the characteristic that the hardware resources of the nodes are limited. In summary, a new access protocol is needed to ensure low-latency and high-reliability transmission of time-sensitive services on the premise of ensuring the performance transmission performance of other services as much as possible.

At present, no explanation or report of the similar technology of the invention is found, and similar data at home and abroad are not collected. The invention has the advantages of absorbing all access protocols in a concurrent manner and improves the self-organizing network hybrid access protocol supporting the reliable transmission of time-sensitive services.

[ summary of the invention ]

The invention aims to provide a self-organizing network which ensures the reliable transmission of high-priority time-sensitive services and does not influence the transmission performance of other services.

In order to achieve the purpose, the technical scheme adopted by the invention is a self-organizing network for ensuring the reliable transmission of the time-sensitive service with high priority, which comprises a plurality of self-organizing network nodes, wherein the self-organizing network nodes communicate through a wireless communication network; the ad hoc network node comprises a processor, a memory, and a wireless communication interface for wireless communication; the memory is stored with a self-organizing network access protocol program, a countdown counter for recording the length of a backoff window, a high-priority time-sensitive service queue for storing high-priority time-sensitive service data and other low-priority service queues for storing other low-priority service data; the self-organizing network node processor is controlled by a self-organizing network access protocol program to realize the following steps:

s1, the self-organizing network node constructs a wireless communication MAC layer time frame, and the length of the single wireless communication MAC layer time frame is t_frame＝t_demandWherein t is_demandThe method is a requirement of single-hop time delay of high-priority time-sensitive service, the length of a time frame of a single wireless communication MAC layer comprises K time slots, and the length of a single time slot is t_slot＝t_frameThe 1 st time slot is a contention time slot, the 2 nd to the K th time slots are service transmission time slots and are marked as the 1 st service transmission time slot to the K-1 st service transmission time slot, the contention time slot comprises M contention sub-time slots according to the shortest physical frame length supported by the self-organizing network node, M, K is a positive integer, M is a positive integer>K-1；

S2, loading a transmission load by the self-organizing network node with the communication requirement, firstly, taking the first data from the high-priority queue, and if the time-sensitive service queue with the high priority is empty, reading the data from other low-priority service queues;

s3, the self-organizing network node loading the transmission load randomly selects the length of a backoff window according to the priority of the service and records the length of the backoff window in a countdown timer, the length of the backoff window randomly selected by the high-priority time-sensitive service is small, the length of the backoff window randomly selected by other low-priority services is large, and the length interval of the backoff window randomly selected by the high-priority time-sensitive service is not overlapped with the length interval of the backoff window randomly selected by other low-priority services;

s4, randomly selecting the self-organizing network node with the length of the backoff window as a transmission time slot competition self-organizing network node, in a new wireless communication MAC layer time frame competition time slot stage, after each competition sub-time slot, subtracting 1 from a countdown counter of the transmission competition self-organizing network node with the value larger than 0, simultaneously immediately sending a transmission competition statement by the transmission time slot competition self-organizing network node with the countdown counter value of 0 through a wireless network, if collision is detected, giving up transmission by the transmission time slot competition self-organizing network node with the countdown counter value of 0 and continuously competing for a service transmission time slot in the next wireless communication MAC layer time frame, and if collision is not detected, determining the service transmission time slot value of the transmission time slot competition self-organizing network node by the self-organizing network node through a service transmission time slot time frame competition arbitration mechanism;

s5, in the wireless communication MAC layer time frame service transmission time slot stage, the self-organizing network node which obtains the service transmission time slot sends the transmission load loaded in the step S2 in the service transmission time slot with the corresponding value through the wireless network.

Further, in the self-organizing network for guaranteeing reliable transmission of the high-priority time-sensitive service, the self-organizing network node further includes an available transmission time slot counter for recording the value of the transmission time slot of the service, and a tone level transceiver for sending and receiving high-level tone signals through the wireless communication interface, and the self-organizing network node processor controlled by the self-organizing network access protocol program further implements the following steps:

step S1, the shortest physical frame length supported by the self-organizing network node is t_hwWherein t is_hw＜t_slotThen the contention slot is further divided intoOne contention sub-slot, t_slot-M_cptt_hwA guard interval between a contention time slot and a service transmission time slot;

step S3, initializing the available transmission time slot counter of the self-organizing network node loaded with the transmission load to K-1;

step S4, the frame competition arbitration mechanism of the service transmission timeslot means that, every time a competition sub-timeslot passes, a transmission timeslot competition self-organizing network node with a countdown counter value of 0 immediately sends a high-level tone signal as a transmission competition statement through the wireless network, and if the transmission timeslot competition self-organizing network node with the countdown counter value greater than 0 monitors the high-level tone signal through the wireless network, the transmission timeslot competition self-organizing network node with the countdown counter value greater than 0 can use the transmission timeslot counter to be decreased by 1; through M_cptAfter each contention sub-slot, the transmission slot contends for the self-organizing network node to determine that the service transmission slot value is K minus the available transmission slot counter value, the transmission slot contending for the self-organizing network node with the available transmission slot counter value being 0 gives up transmission and continuously contends for the service transmission slot in the next wireless communication MAC layer time frame.

Preferably, the above mentioned self-organizing network high-priority time-sensitive service single-hop delay requirement t for ensuring reliable transmission of high-priority time-sensitive service_demandThe frame length of the single wireless communication MAC layer time frame is 2ms, the frame length of the single wireless communication MAC layer time frame comprises 4 time slots with the length of 0.5ms, the shortest physical frame length supported by the self-organizing network node is 60us, the competition time slot is further divided into 8 competition sub time slots, and 20us is a protection interval between the competition time slot and the service transmission time slot.

Further, in the self-organizing network for ensuring reliable transmission of the high-priority time-sensitive service, the self-organizing network node processor is a processor with short-time data packet analysis and fast transceiving conversion capabilities, and the self-organizing network node processor is controlled by a self-organizing network access protocol program and further realizes the following functions:

step S1, the shortest physical frame length supported by the self-organizing network node is t_hwWherein t is_hw＜t_slotThen the contention slot is further divided intoSub-slots of 1 to M_cpt-1 sub-slot is a contention sub-slot, Mth_cptSub-slot plus guard interval duration t_slot-M_cptt_hwIs a reserved broadcast sub-slot;

step S4, the frame competition arbitration mechanism of the service transmission timeslot means that, each time a competition sub-timeslot passes, a transmission timeslot competition self-organized network node with a counter value of 0 when counting down immediately sends the ID number of the node through the wireless network as a transmission competition statement, the first transmission timeslot competition self-organized network node that sends the ID number of the node through the wireless network in the competition sub-timeslot and does not detect a collision is a master node, and the master node is responsible for monitoring the node ID number sent by the transmission timeslot competition self-organized network node through the wireless network; through M_cptAfter 1 competition sub-time slot, the main node determines the service transmission time slot value of the transmission time slot competition self-organizing network node according to the sequence of the monitored node ID numbers through analysis, and sends a reserved broadcast subframe in the reserved broadcast sub-time slot to inform other transmission time slot competition self-organizing network nodes, and the transmission time slot competition self-organizing network node which does not obtain the service transmission time slot abandons transmission and continues to compete for the service transmission time slot in the next wireless communication MAC layer time frame.

Preferably, the above mentioned self-organizing network high-priority time-sensitive service single-hop delay requirement t for ensuring reliable transmission of high-priority time-sensitive service_demandThe frame length of the single wireless communication MAC layer time frame is 2ms, the frame length of the single wireless communication MAC layer time frame comprises 4 time slots with the length of 0.5ms, the shortest physical frame length supported by the self-organizing network node is 60us, and the competition time slot is further divided into 7 competition sub-time slots and 1 reserved broadcast sub-time slot.

Preferably, the self-organizing network node is an unmanned aerial vehicle self-organizing network node.

The invention has the following beneficial effects of ensuring the reliable transmission of the high-priority time-sensitive service: by combining the ideas of TDMA fixed frame length, CSMA carrier sense and SPMA priority differentiation, the method has the advantages of absorbing all protocols accumulatively, designs a hybrid access protocol capable of supporting reliable transmission of time-sensitive services, and realizes 1, in a self-organizing network form, low-delay high-reliability transmission of the time-sensitive services with single-hop delay requirements of less than 2ms is supported; 2. the access protocol can distinguish different priorities, and guarantees the fairness of the network transmission performance of other services and the competition of network resources while realizing the low-delay and high-reliability transmission of time-sensitive services; 3. the protocol implementation has flexibility, two protocol implementation modes with different hardware complexity are supported, and the transmission performance under different implementation modes is basically consistent under the condition of medium and low network load.

[ description of the drawings ]

Fig. 1 is a diagram of communication steps of an ad hoc network for ensuring reliable transmission of high-priority time-sensitive services.

Fig. 2 is a schematic diagram of an ad hoc network node for guaranteeing reliable transmission of a high-priority time-sensitive service in a "contention" scheme.

Fig. 3 is a schematic diagram of an ad hoc network node for guaranteeing reliable transmission of a high-priority time-sensitive service in a contention + reservation scheme.

Fig. 4 is a schematic diagram of a time frame structure of an unmanned aerial vehicle ad hoc network access protocol for guaranteeing reliable transmission of high-priority time-sensitive services in a contention scheme.

Fig. 5 is a schematic diagram of a time frame structure of an unmanned aerial vehicle ad hoc network access protocol for ensuring reliable transmission of a high-priority time-sensitive service in a "contention + reservation" scheme.

[ detailed description ] embodiments

The invention is further described with reference to the following examples and with reference to the accompanying drawings.

Example 1

The embodiment realizes the self-organizing network for ensuring the reliable transmission of the time-sensitive service with high priority.

Fig. 1 is a diagram of communication steps of an ad hoc network for ensuring reliable transmission of high-priority time-sensitive services. As shown in fig. 1, the self-organizing network for guaranteeing reliable transmission of time-sensitive services with high priority in the embodiment includes a plurality of self-organizing network nodes, where the plurality of self-organizing network nodes communicate through a wireless communication network; the ad hoc network node comprises a processor, a memory, and a wireless communication interface for wireless communication; the memory is stored with a self-organizing network access protocol program, a countdown counter for recording the length of a backoff window, a high-priority time-sensitive service queue for storing high-priority time-sensitive service data and other low-priority service queues for storing other low-priority service data; the self-organizing network node processor is controlled by a self-organizing network access protocol program to realize the following steps:

s1, the self-organizing network node constructs a wireless communication MAC layer time frame, and the length of the single wireless communication MAC layer time frame is t_frame＝t_demandWherein t is_demandThe method is a requirement of single-hop time delay of high-priority time-sensitive service, the length of a time frame of a single wireless communication MAC layer comprises K time slots, and the length of a single time slot is t_slot＝t_frameThe 1 st time slot is a contention time slot, the 2 nd to the K th time slots are service transmission time slots and are marked as the 1 st service transmission time slot to the K-1 st service transmission time slot, the contention time slot comprises M contention sub-time slots according to the shortest physical frame length supported by the self-organizing network node, M, K is a positive integer, M is a positive integer>K-1；

S2, loading a transmission load by the self-organizing network node with the communication requirement, firstly, taking the first data from the high-priority queue, and if the time-sensitive service queue with the high priority is empty, reading the data from other low-priority service queues;

s3, the self-organizing network node loading the transmission load randomly selects the length of a backoff window according to the priority of the service and records the length of the backoff window in a countdown timer, the length of the backoff window randomly selected by the high-priority time-sensitive service is small, the length of the backoff window randomly selected by other low-priority services is large, and the length interval of the backoff window randomly selected by the high-priority time-sensitive service is not overlapped with the length interval of the backoff window randomly selected by other low-priority services;

s4, randomly selecting the self-organizing network node with the length of the backoff window as a transmission time slot competition self-organizing network node, in a new wireless communication MAC layer time frame competition time slot stage, after each competition sub-time slot, subtracting 1 from a countdown counter of the transmission competition self-organizing network node with the value larger than 0, simultaneously immediately sending a transmission competition statement by the transmission time slot competition self-organizing network node with the countdown counter value of 0 through a wireless network, if collision is detected, giving up transmission by the transmission time slot competition self-organizing network node with the countdown counter value of 0 and continuously competing for a service transmission time slot in the next wireless communication MAC layer time frame, and if collision is not detected, determining the service transmission time slot value of the transmission time slot competition self-organizing network node by the self-organizing network node through a service transmission time slot time frame competition arbitration mechanism;

s5, in the wireless communication MAC layer time frame service transmission time slot stage, the self-organizing network node which obtains the service transmission time slot sends the transmission load loaded in the step S2 in the service transmission time slot with the corresponding value through the wireless network.

Fig. 2 is a schematic diagram of an ad hoc network node for guaranteeing reliable transmission of a high-priority time-sensitive service in a "contention" scheme. As shown in fig. 2, in addition, in the ad hoc network for guaranteeing reliable transmission of high-priority time-sensitive services according to the present embodiment, the ad hoc network node further includes an available transmission time slot counter for recording a value of a transmission time slot of a service, and a tone level transceiver for transmitting and receiving high-level tone signals through a wireless communication interface, and the ad hoc network node processor under the control of an ad hoc network access protocol program further implements the following steps:

step S1, the shortest physical frame length supported by the self-organizing network node is t_hwWherein t is_hw＜t_slotThen the contention slot is further divided intoOne contention sub-slot, t_slot-M_cptt_hwA guard interval between a contention time slot and a service transmission time slot;

step S3, initializing the available transmission time slot counter of the self-organizing network node loaded with the transmission load to K-1;

step S4, the frame competition arbitration mechanism of the service transmission time slot means that every time one frame is passedIf the transmission time slot competition self-organization network node with the countdown counter value larger than 0 monitors the high-level single-tone signal through the wireless network, the transmission time slot competition self-organization network node with the countdown counter value larger than 0 can use the transmission time slot counter to subtract 1; through M_cptAfter each contention sub-slot, the transmission slot contends for the self-organizing network node to determine that the service transmission slot value is K minus the available transmission slot counter value, the transmission slot contending for the self-organizing network node with the available transmission slot counter value being 0 gives up transmission and continuously contends for the service transmission slot in the next wireless communication MAC layer time frame.

Preferably, the above mentioned self-organizing network high-priority time-sensitive service single-hop delay requirement t for ensuring reliable transmission of high-priority time-sensitive service_demandThe frame length of the single wireless communication MAC layer time frame is 2ms, the frame length of the single wireless communication MAC layer time frame comprises 4 time slots with the length of 0.5ms, the shortest physical frame length supported by the self-organizing network node is 60us, the competition time slot is further divided into 8 competition sub time slots, and 20us is a protection interval between the competition time slot and the service transmission time slot.

Fig. 3 is a schematic diagram of an ad hoc network node for guaranteeing reliable transmission of a high-priority time-sensitive service in a contention + reservation scheme. As shown in fig. 3, in this embodiment, in a self-organizing network for guaranteeing reliable transmission of a high-priority time-sensitive service, the self-organizing network node processor is a processor with short-time packet parsing and fast transceiving and converting capabilities, and the self-organizing network node processor is controlled by a self-organizing network access protocol program to further implement the following functions:

step S1, the shortest physical frame length supported by the self-organizing network node is t_hwWherein t is_hw＜t_slotThen the contention slot is further divided intoSub-slots of 1 to M_cpt-1 pieces ofThe sub-slot is a contention sub-slot, Mth_cptSub-slot plus guard interval duration t_slot-M_cptt_hwIs a reserved broadcast sub-slot;

step S4, the frame competition arbitration mechanism of the service transmission timeslot means that, each time a competition sub-timeslot passes, a transmission timeslot competition self-organized network node with a counter value of 0 when counting down immediately sends the ID number of the node through the wireless network as a transmission competition statement, the first transmission timeslot competition self-organized network node that sends the ID number of the node through the wireless network in the competition sub-timeslot and does not detect a collision is a master node, and the master node is responsible for monitoring the node ID number sent by the transmission timeslot competition self-organized network node through the wireless network; through M_cptAfter 1 competition sub-time slot, the main node determines the service transmission time slot value of the transmission time slot competition self-organizing network node according to the sequence of the monitored node ID numbers through analysis, and sends a reserved broadcast subframe in the reserved broadcast sub-time slot to inform other transmission time slot competition self-organizing network nodes, and the transmission time slot competition self-organizing network node which does not obtain the service transmission time slot abandons transmission and continues to compete for the service transmission time slot in the next wireless communication MAC layer time frame.

Preferably, the above mentioned self-organizing network high-priority time-sensitive service single-hop delay requirement t for ensuring reliable transmission of high-priority time-sensitive service_demandThe frame length of the single wireless communication MAC layer time frame is 2ms, the frame length of the single wireless communication MAC layer time frame comprises 4 time slots with the length of 0.5ms, the shortest physical frame length supported by the self-organizing network node is 60us, and the competition time slot is further divided into 7 competition sub-time slots and 1 reserved broadcast sub-time slot.

Preferably, the self-organizing network node is an unmanned aerial vehicle self-organizing network node.

Example 2

The embodiment realizes the unmanned aerial vehicle self-organizing network access protocol for ensuring the reliable transmission of the high-priority time-sensitive service.

The unmanned aerial vehicle self-organizing network access protocol for guaranteeing reliable transmission of the high-priority time-sensitive service can guarantee low-delay and high-reliability transmission of the time-sensitive service while hardly affecting the transmission performance of other service networks. Meanwhile, the unmanned aerial vehicle self-organizing network access protocol for guaranteeing reliable transmission of the high-priority time-sensitive service can support two implementation schemes with different hardware complexity, the two implementation schemes have consistent performance under the medium-low network load, and the practicability of the self-organizing network access protocol is greatly improved.

The unmanned aerial vehicle self-organizing network access protocol for guaranteeing reliable transmission of the high-priority time-sensitive service can support the high-reliability transmission of the time-sensitive service with the requirement of single-hop delay of the self-organizing network below 2ms under different hardware capabilities. The method comprises a competition type MAC layer time frame structure and a competition + reservation type MAC layer time frame structure.

Wherein, the MAC layer time frame structure of the said "competition type": the requirement on hardware capability is low, only the hardware has the resolving capability of a single-tone signal (high level), and a mechanism of node competition, fixed time slot division and random backoff is used for effectively ensuring low-delay and high-reliability transmission of data service. The time frame structure comprises a contention sub-frame and a traffic transmission sub-frame.

The MAC layer time frame structure of the competition + reservation type is as follows: the requirement on hardware capability is high, the hardware is required to have the capability of analyzing the data packet header in a short time and carrying out rapid transceiving conversion, and a mechanism of node competition and reservation plus fixed time slot division is used for guaranteeing reliable transmission more efficiently under the condition of meeting low time delay. The time frame structure comprises a contention subframe, a reserved broadcast subframe and a service transmission subframe.

In this embodiment, an access protocol of an unmanned aerial vehicle ad hoc network for low latency services is provided, where each node in the ad hoc network is designed with two priority queues, a countdown counter, and an available transmission timeslot counter.

A priority queue: each communication node in the self-organizing network maintains 2 priority queues, wherein one queue is used for storing time-sensitive services with high priority, and the other queue is used for storing other services with low priority. When the node has a communication demand, the node firstly takes the first data from the high priority queue, and if the high priority queue is empty, the node reads the data from the low priority queue.

A countdown timer: each node will maintain a counter for recording the length of the real-time backoff window in the contention subframe phase. If the length of the back-off window is 0, the node immediately communicates, otherwise, the length of the back-off window is reduced by 1 every sub-time slot.

Available transmission slot counter: for the 'competitive' MAC layer time frame structure, each node maintains an available transmission time slot counter in the competitive subframe stage, and each time frame of the available transmission time slot counter is initialized to the time slot number of the subframe capable of sending service transmission; every time the information that other nodes need to communicate is detected in the channel, the node reduces the available transmission time slot counter by 1, the node reduces the available transmission time slot counter of the current time frame to 0, and the node competes for the available transmission time slot counter to send a service transmission subframe in the next time frame; for the MAC layer time frame structure of the competition and reservation type, an available transmission time slot counter is not maintained.

The competition MAC layer time frame structure is characterized in that if the single-hop time delay requirement of the time-sensitive service is t_demand(t_demandLess than 2ms), the single time frame length is t_frame＝t_demand. If the length of a single time frame is K time slots, the length of the single time slot in the time frame is t_slot＝t_frameand/K. The contention sub-frame consists of the 1 st time slot, and the service transmission sub-frame consists of the 2 nd to the K time slots. Let t be the shortest physical frame length supported by hardware_hw(t_hw＜t_slot) Then dividing the contention sub-frame into a plurality of sub-framesSub-slots, will t_slot-M_cptt_hwA guard interval between the contention sub-frame and the traffic transmission sub-frame is set.

The MAC layer time frame structure of the 'competition + reservation type' has t single-hop time delay requirement of the time-sensitive service_demand(t_demandLess than 2ms), the single time frame length is t_frame＝t_demand. If the length of a single time frame is K time slots, the length of the single time slot in the time frame is t_slot＝t_frameand/K. The contention and reservation subframe consists of the 1 st time slot, and the service transmission subframe consists of the 2 nd to the K time slots. Let t be the shortest physical frame length supported by hardware_hw(t_hw＜t_slot) Then the 1 st slot, i.e. contention and reservation subframe, is further divided intoSub-slots, the contention sub-frame occupying 1 to M_cpt-1 sub-slot, said reserved broadcast sub-frame occupying Mth_cptSub-slots and duration of 1 guard interval (i.e., t)_slot-M_cptt_hw)。

In the contention-based MAC layer time frame structure, all nodes contend for a transmission opportunity according to the following rule to transmit a time-sensitive service:

for all nodes with loads waiting for transmission in the self-organizing network, the nodes randomly select backoff windows according to the priorities of services at first, and it is worth noting that the backoff windows of time-sensitive services with high priority are smaller, and the backoff windows of other services with low priority are larger.

After the backoff window is selected, all the nodes repeat the following actions: if the countdown timer is 0, the node immediately sends a competition statement (a high-level single tone signal) to the channel, if collision is detected, the time slot competition fails, the node abandons the transmission of the time slot and continues to compete for the transmission time slot in the next time frame, and if collision is not detected, the corresponding time slot in the service transmission subframe is used for transmitting the time-sensitive service; if the count-down time of the node is not zero, the node monitors the channel. If a high level single tone signal is detected, the available transmission time slot counter of the node is decreased by 1. Every time all nodes go through 1 sub-slot, the countdown counter of each node will automatically decrement by 1.

In the MAC layer time frame structure of the 'contention + reservation type', each time frame defines a node which sends a message to a channel first in a contention subframe as a master node. All nodes in the self-organizing network compete for transmission opportunities according to the following rules so as to transmit the time-sensitive services:

for all nodes with loads waiting for transmission in the self-organizing network, the nodes randomly select a backoff window according to the priority of the service.

After the backoff window is selected, all the nodes repeat the following actions: if the countdown timer is 0, the node immediately sends the ID number of the node to the channel, if the collision is detected, the time slot competition fails, the node abandons the transmission of the time slot and continuously competes for transmitting the time slot in the next time frame; if the count-down time counter is not 0, the node monitors the channel. Every time all nodes go through 1 sub-slot, the countdown counter of each node will automatically decrement by 1.

In the broadcast subframe reserving stage, the main node of the time frame counts the time slot reserving information of the nodes to be sent of the self-organizing network, and broadcasts the processed time slot reserving information to the nodes of the whole network.

And the node to be transmitted selects a corresponding time slot according to the time slot reservation information broadcasted by the main node to carry out time-sensitive service transmission.

The unmanned aerial vehicle self-organizing network access protocol for guaranteeing reliable transmission of the high-priority time-sensitive service can support low-delay and high-reliability transmission of the time-sensitive service with the single-hop delay requirement of less than 2ms in the self-organizing network form; the access protocol can distinguish different priorities, and guarantees the fairness of the network transmission performance of other services and the competition of network resources while realizing the low-delay and high-reliability transmission of time-sensitive services; the protocol implementation has flexibility, two protocol implementation modes with different hardware complexity are supported, and the transmission performance under different implementation modes is basically consistent under the condition of medium and low network load.

Example 3

The embodiment realizes the unmanned aerial vehicle self-organizing network access protocol for ensuring the reliable transmission of the high-priority time-sensitive service.

The present embodiment provides an unmanned aerial vehicle ad hoc network access protocol for guaranteeing reliable transmission of high-priority time-sensitive services, including two implementation manners corresponding to different hardware capabilities: the "contention" scheme is in contrast to the "contention + reservation" scheme. Both implementations require the node to have a priority queue, a countdown counter. Where the "contention" scheme requires an additional counter of available transmission slots. The details of these two implementations will be described separately below.

Fig. 4 is a schematic diagram of a time frame structure of an unmanned aerial vehicle ad hoc network access protocol for guaranteeing reliable transmission of high-priority time-sensitive services in a contention scheme. As shown in fig. 4, in the contention scheme of the unmanned aerial vehicle ad hoc network access protocol for guaranteeing reliable transmission of high-priority time-sensitive services, which has lower requirements for hardware, the frame structure of the contention scheme access protocol is composed of contention subframes and service transmission subframes on the premise that node hardware has the capability of sending and analyzing a high-level single tone signal. The length of a single time frame is 2ms, and the single time frame is divided into 4 time slots with the length of 0.5ms, wherein the 1 st time slot is used as a competition subframe, and the 2 nd to 4 th time slots are used as service transmission subframes. Assuming that the shortest physical frame length that can be supported by hardware is 60us, the contention sub-frame may be further divided into 8 sub-slots, and the duration of each sub-slot is the shortest physical frame length. The remaining 20us of the contention subframe is used as a guard interval between the contention subframe and the traffic transmission subframe.

The specific transmission process of the unmanned aerial vehicle ad hoc network access protocol contention scheme for ensuring reliable transmission of the high-priority time-sensitive service in the embodiment is described as follows. At the beginning of each 2ms time frame, all nodes to send services select the service with the highest priority in their queues, and then randomly select one value in the contention window to count down. The contention windows for different priority services take different ranges and there is no intersection. For example, in a certain time frame, the high priority contention window takes [0,2], and the low priority window takes [3,8 ]. Assuming that there are 5 nodes A-E in the network at this time, the countdown counter is selected as follows: a is 2, B, C is 3, D is 4 and E is 5. The starting time of the time frame is set to 0 us. Firstly, all nodes enter a listening mode, after 120 mu s, the counter of A counts down to finish, a high-level single-tone signal is sent to declare the time slot occupation, and after 60 mu s, other nodes hear the signal and know that one time slot is occupied. Since each node has one available transmission slot counter and a traffic transmission subframe has 3 slots, the available transmission slot counters of all nodes are initialized to 3. And, every time the node hears a signal, decrements the available transmission slot counter by 1. Therefore, when other nodes hear the slot occupation signal, the available transmission slot counter becomes 2, when 180 μ s, the counter countdown of B, C nodes is finished, two nodes each send a high level tone signal, after the D, E node hears the signal, the channel counter is decreased by 1 again to become 1, then when 240 μ s, the D node sends a signal to compete for the slot, and the E node sets the channel counter to 0 because of hearing the competition signal at 300 μ s, at this time, the E finds that there is no available slot in the frame, so it will re-compete for the slot in the next frame. B. Since the two nodes C simultaneously transmit a high-level tone signal at 180 μ s, when the two nodes B, C detect a collision at 180 μ s, the time slot contention of the two nodes B, C fails, and the two nodes B, C abandon the transmission of the time slot and continue to contend for the transmission time slot in the next time frame.

Fig. 5 is a schematic diagram of a time frame structure of an unmanned aerial vehicle ad hoc network access protocol for ensuring reliable transmission of a high-priority time-sensitive service in a "contention + reservation" scheme. As shown in fig. 5, in the solution of the contention and reservation that the requirement of the self-organizing network access protocol of the unmanned aerial vehicle for guaranteeing reliable transmission of the high-priority time-sensitive service on hardware is high in this embodiment, on the premise that node hardware has the capability of rapidly analyzing a packet header and rapidly performing transceiving conversion, a frame structure of the contention and reservation solution is composed of contention subframes, reservation broadcast subframes, and service transmission subframes. The length of a single time frame is 2ms, and the single time frame is divided into 4 time slots with the length of 0.5ms, wherein the 1 st time slot is used as a competition and reservation broadcasting subframe, and the 2 nd to 4 th time slots are used as service transmission subframes. Assuming that the shortest physical frame length that the hardware can support is 60us, the length of each sub-slot in the 1 st slot is one shortest physical frame length. The contention sub-frame occupies 7 sub-slots for a total of 420 us. The remaining 80us in the 1 st slot is used as a reserved broadcast subframe. In the "contention + reservation" scheme, there is no guard interval between three subframes.

The specific transmission process of the unmanned aerial vehicle ad hoc network access protocol 'contention + reservation' scheme for ensuring reliable transmission of the high-priority time-sensitive service in the embodiment is described as follows. In the "contention + reservation" scheme, the signaling information broadcast by all nodes changes from high level to node ID number, and the master node of the current frame is defined as the first node to send signaling. The following is still illustrated in terms of a network scenario for a "contention" scheme. Assuming that there are 5 nodes to be transmitted in total, their countdown counters are selected as follows: a is 2, B, C is 3, D is 4, E is 5, when A is the master node. In the 2 nd sub-time slot, the node A broadcasts an ID number, and other nodes can receive the ID number; in the 3 rd sub-slot, the ID messages broadcast by B, C two nodes collide, and the A, D, E node cannot receive correctly, so that the A, D, E node can only judge that there is a node competing for the slot according to the received signal level, but does not know that B and C are competing; next, in the 4 th and 5 th sub-slots, D and E broadcast their ID numbers respectively, and the other nodes receive them correctly. When the contention sub-frame is over, the main node a analyzes that the node that needs to transmit data in the frame is A, D, E, so that A, D, E occupies three service slots in sequence, and the node a broadcasts the information to other nodes in a reserved broadcast sub-frame (that is, a reserved sub-frame, which is a broadcast packet transmitted to all nodes). When B and C receive the allocation result, they know that they will collide in the current frame, so B and C will not transmit data in the current frame, but will reset the counter value in the next frame and re-compete.

It will be understood by those skilled in the art that all or part of the steps of implementing the above embodiments may be implemented by hardware, or may be implemented by a program instructing associated hardware, and the program may be stored in a computer-readable storage medium, where the storage medium may be a magnetic disk, an optical disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), or the like.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and additions can be made without departing from the principle of the present invention, and these should also be considered as the protection scope of the present invention.