阅读说明：本技术 一种自适应时隙的邻节点发现方法 (Self-adaptive time slot neighbor node discovery method ) 是由 毕超豪 王遂 杨文清 黄威 邓烨恒 唐金锐 唐若笠 于 2021-07-26 设计创作，主要内容包括：本发明公开了一种自适应时隙的邻节点发现方法,实现步骤为：各节点初始化相关参数；计算各波束方向的基础时隙长度和总时隙长度；对扫描序列中的首个波束方向执行邻节点发现,若成功发现邻节点,则其基础时隙个数加1,该波束方向被分配更多资源后重新计算总时隙长度并重复进行邻节点发现；若未能发现邻节点,则转至下一波束方向,并对其按上述过程进行邻节点发现；扫描序列遍历完毕后,用尚未发现足够数量邻节点的波束方向构建新的扫描序列,并重复上述过程直至达到终止条件。本发明的优点在于,各波束方向可自适应地动态调整邻节点发现策略,集中资源快速完成部分波束方向的邻节点发现任务,从而减少资源浪费,提升邻节点发现效率。(The invention discloses a method for discovering a neighbor node of a self-adaptive time slot, which comprises the following steps: initializing relevant parameters by each node; calculating the basic time slot length and the total time slot length of each beam direction; performing adjacent node discovery on a first beam direction in the scanning sequence, if the adjacent node is successfully discovered, adding 1 to the number of basic time slots, recalculating the total time slot length after more resources are allocated to the beam direction, and repeatedly discovering the adjacent node; if the adjacent node can not be found, switching to the next beam direction, and carrying out adjacent node discovery on the adjacent node according to the process; and after traversing the scanning sequence, constructing a new scanning sequence by using the beam directions of which a sufficient number of adjacent nodes are not found, and repeating the process until a termination condition is reached. The method has the advantages that the adjacent node discovery strategy can be dynamically adjusted in a self-adaptive manner in each beam direction, and the adjacent node discovery tasks in partial beam directions can be rapidly completed by concentrating resources, so that the resource waste is reduced, and the adjacent node discovery efficiency is improved.)

1. A method for discovering neighbor nodes of a self-adaptive time slot is characterized by comprising the following steps:

step 1: for the wireless self-organizing network based on the directional antenna, each node calculates the total number of wave beam directions of the nodes according to the wave beam angle of the directional antenna, sets a target value and the maximum scanning period number found by adjacent nodes, and initializes a scanning sequence, an adjacent node table of each wave beam direction, the number of adjacent nodes in the adjacent node table of each wave beam direction and the number of basic time slots of each wave beam direction;

step 2: calculating the basic time slot length of each beam direction in the scanning sequence in the t-th scanning period;

and step 3: taking a first beam direction in a scanning sequence in the t-th scanning period as a current beam direction;

and 4, step 4: calculating the total time slot length of the neighbor node discovery operation executed in the current beam direction;

and 5: for the current beam direction, performing neighbor node discovery operation by adopting the total time slot length determined in the step 4;

step 6: if the current beam direction successfully finds a new neighbor node in the step 5, updating the neighbor node table of the current beam direction, adding 1 to the number of basic time slots of the current beam direction, and then jumping to the step 4 to recalculate the total time slot length of the current beam direction and re-execute the neighbor node finding operation; if no new neighbor node is found in the current beam direction in step 5, executing step 7;

and 7: taking the next beam direction in the scanning sequence in the t-th scanning period as the current beam direction, and repeatedly executing the steps 4 to 6 until all beam directions in the scanning sequence in the t-th scanning period are traversed;

and 8: constructing a scanning sequence in the t +1 th scanning period;

and step 9: if the scanning sequence in the t +1 th scanning period is empty, the adjacent node discovery process is finished; otherwise, repeating the step 2 to the step 8 until the current scanning period number reaches the maximum scanning period number, and ending the adjacent node discovery process;

the scanning sequence in the tth scanning period in the step 2 is as follows:

wherein S is_tDenotes the scanning sequence in the t-th scanning period, D_{t_k}Denotes the kth beam direction in the scan sequence in the t-th scan period, t _ k ∈ [1, d ∈ ]]，k∈[1,L_t]D represents the total number of beam directions of the nodes, L_tDenotes the number of beam directions in the scanning sequence in the t-th scanning period, t is 0,1,2, …, N_s-max，N_s-maxRepresents the maximum number of scan cycles;

step 2, calculating the length of the basic time slot of each beam direction specifically includes:

wherein l_{t_k}，t_k∈[1,d]，t∈[0,N_s-max]，k＝1,2,…,L_tThe length of a basic time slot in the k beam direction in a scanning sequence in the t scanning period; d is the total number of wave beam directions of the nodes; l₀Is a predefined unit reference time slot length; lambda belongs to [1.21.5 ]]Allocating coefficients for predefined time slots; n _ node_{t_k}，t_k∈[1,d]，t∈[0,N_s-max]，k＝1,2,…,L_tThe adjacent node number in the adjacent node table of the kth wave beam direction in the scanning sequence in the t-th scanning period;

step 4, the current beam direction is: d_current；

Step 4, calculating the total time slot length of the neighbor node discovery operation executed in the current beam direction specifically includes:

L_current＝n_current·l_current

wherein L is_currentThe total time slot length in the current beam direction; n is_currentThe number of basic time slots in the current beam direction; l_currentThe length of a basic time slot of the current beam direction;

step 6, the current beam direction is: d_current；

Step 6, updating the neighbor node table in the current beam direction specifically includes: will present beam direction D_currentAdding the information such as the ID number, azimuth angle and the like of the new neighbor node successfully found in the step 5 into the neighbor node table in the current beam direction;

step 6, the number of the basic time slots in the current beam direction is: n is_current；

Step 6, the total time slot length in the current beam direction is: l is_current。

2. The method of claim 1, wherein the directional antenna beam angle in step 1 is: theta;

step 1, the total number of beam directions of the computing nodes is as follows: d is 360 DEG/theta;

the beam direction in step 1 is: d_i，i＝1,2,…,d；

The target value found by the adjacent node in the step 1 is as follows: n is a radical of_target；

Step 1 the maximum number of scanning cycles is: n is a radical of_s-max；

The scanning sequence in the step 1 is as follows: s_t,t＝0,1,2,…,N_s-maxInitialize it to S₀＝{D₁,D₂,…,D_d}；

Step 1, the neighbor node table of each beam direction is: node _ Table_iI 1,2, …, d, all initialized to null;

the number of the adjacent nodes in the adjacent node table in each beam direction in the step 1 is as follows: n _ node_iI 1,2, …, d, all initialized to 0;

step 1, the number of basic time slots in each beam direction is: n is_i，i＝1,2,…,d。

3. The method of claim 1, wherein the first beam direction in the scanning sequence in the t-th scanning period in step 3 is:

D_{t_1}，t_1∈[1,d]，t∈[0,N_s-max]d is the total number of node beam directions, N_s-maxThe maximum number of scanning cycles;

step 3, the current beam direction is: d_current。

4. The method of claim 1, wherein the current beam direction in step 5 is: d_current；

Step 5, executing the neighbor node discovery operation by using the total time slot length determined in step 4, specifically:

for the current beam direction D_currentTotal execution duration of L_currentIncluding in particular n_currentSearching for each time slot with length of l_current；

The mode of each search randomly selects one of the following three modes to execute:

mode 1: in a basic time slot length l_currentContinuously sending hello information to finish one-time searching;

mode 2: in a basic time slot length l_currentContinuously receiving hello information to finish one-time searching;

mode 3: in a basic time slot length l_currentInternal dormancy to complete one search;

if the current beam direction D_currentThe successful reception of hello information sent by another new neighbor node in the time slot for receiving hello information indicates the current beam direction D_currentThe new neighbor node is successfully discovered.

5. The adaptive slotted neighbor node discovery method according to claim 1, wherein said scanning in said tth scanning period of step 7The drawing sequence is as follows:

wherein S is_tDenotes the scanning sequence in the t-th scanning period, D_{t_k}Denotes the kth beam direction in the scan sequence in the t-th scan period, t _ k ∈ [1, d ∈ ]]，k∈[1,L_t]D represents the total number of beam directions of the nodes, L_tDenotes the number of beam directions in the scanning sequence in the t-th scanning period, t is 0,1,2, …, N_s-max，N_s-maxRepresents the maximum number of scan cycles;

the current beam direction in step 7 is: d_current。

6. The method for discovering neighbor nodes in an adaptive timeslot according to claim 1, wherein the step 8 of constructing the scan sequence in the t +1 th scan period specifically includes:

for the scanning sequence S in the t-th scanning period_tIn each beam direction, i.e. D_{t_k}，t_k∈[1,d]，k＝1,2,…,L_tThe following determination is performed:

if N _ node_{t_k}≥N_targetThen D is_{t_k}Not adding the scanning sequence in the t +1 th scanning period, i.e. S_(t+1)；

Otherwise, the beam direction is D_{t_k}Adding the scanning sequence in the t +1 th scanning period, i.e. S_(t+1)；

Wherein N is_targetTarget value, N _ node, representing neighbor discovery_{t_k}Indicates the number of adjacent nodes in the k beam direction adjacent node table in the scanning sequence in the t scanning period, wherein t is 0,1,2, …, N_s-max，N_s-maxThe maximum number of scan cycles.

Technical Field

The invention relates to the technical field of wireless communication, in particular to a time slot self-adaptive neighbor node discovery method.

Background

The wireless self-organizing network is a wireless communication network which is composed of multiple nodes and has the characteristics of dynamic networking, multi-hop, mobility and the like, and is widely applied to a plurality of occasions with special communication requirements, such as military affairs, disaster relief, power construction and the like.

When the nodes of the wireless self-organizing network are in networking communication, neighbor node discovery operation needs to be completed on each network node, which is also a necessary link for establishing dynamic topology of the wireless self-organizing network. The directional antenna has unique advantages in realizing long-distance and low-delay information transmission because the energy can be concentrated in a specific direction through the transmission and the reception of directional beams. For this reason, directional antenna based network nodes are widely adopted in the arrangement of many wireless ad hoc networks. However, since directional antennas cannot transmit and receive signals over a 360 ° range at the same time, an efficient neighbor discovery algorithm has a significant impact on the communication efficiency of such wireless ad hoc networks. The invention provides a self-adaptive time slot neighbor node discovery method aiming at a wireless self-organizing network based on a directional antenna, so as to realize the improvement of network neighbor node discovery efficiency through self-adaptive optimization of time slot allocation.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a method for discovering a neighbor node of a self-adaptive timeslot, aiming at the defects in the prior art.

The technical scheme adopted by the invention for solving the technical problems is as follows: a method for discovering neighbor nodes of an adaptive time slot comprises the following steps:

step 1: for the wireless self-organizing network based on the directional antenna, each node calculates the total number of wave beam directions of the nodes according to the wave beam angle of the directional antenna, sets a target value and the maximum scanning period number found by adjacent nodes, and initializes a scanning sequence, an adjacent node table of each wave beam direction, the number of adjacent nodes in the adjacent node table of each wave beam direction and the number of basic time slots of each wave beam direction;

step 2: calculating the basic time slot length of each beam direction in the scanning sequence in the t-th scanning period;

and step 3: taking a first beam direction in a scanning sequence in the t-th scanning period as a current beam direction;

and 4, step 4: calculating the total time slot length of the neighbor node discovery operation executed in the current beam direction;

and 5: for the current beam direction, performing neighbor node discovery operation by adopting the total time slot length determined in the step 4;

step 6: if the current beam direction successfully finds a new neighbor node in the step 5, updating the neighbor node table of the current beam direction, adding 1 to the number of basic time slots of the current beam direction, and then jumping to the step 4 to recalculate the total time slot length of the current beam direction and re-execute the neighbor node finding operation; if no new neighbor node is found in the current beam direction in step 5, executing step 7;

and 7: taking the next beam direction in the scanning sequence in the t-th scanning period as the current beam direction, and repeatedly executing the steps 4 to 6 until all beam directions in the scanning sequence in the t-th scanning period are traversed;

and 8: constructing a scanning sequence in the t +1 th scanning period;

and step 9: if the scanning sequence in the t +1 th scanning period is empty, the adjacent node discovery process is finished; otherwise, repeating the steps 2 to 8 until the current scanning period number reaches the maximum scanning period number N_s-maxThe neighbor discovery process ends.

Preferably, the beam angle of the directional antenna in step 1 is: theta;

step 1, the total number of beam directions of the computing nodes is as follows: d is 360 DEG/theta;

the beam direction in step 1 is: d_i，i＝1,2,…,d；

The target value found by the adjacent node in the step 1 is as follows: n is a radical of_target；

Step 1 the maximum number of scanning cycles is: n is a radical of_s-max；

The scanning sequence in the step 1 is as follows: s_t,t＝0,1,2,…,N_s-maxInitialize it to S₀＝{D₁,D₂,…,D_d}；

Step 1, the neighbor node table of each beam direction is: node _ Table_iI 1,2, …, d, all initialized to null;

the number of the adjacent nodes in the adjacent node table in each beam direction in the step 1 is as follows: n _ node_iI 1,2, …, d, all initialized to 0;

step 1, the number of basic time slots in each beam direction is: n is_i，i＝1,2,…,d；

Preferably, the scanning sequence in the t-th scanning period in step 2 is as follows:

S_t＝{D_{t_1},D_{t_2},...,D_{t_Lt}}；

wherein S is_tDenotes the scanning sequence in the t-th scanning period, D_{t_k}Denotes the kth beam direction in the scan sequence in the t-th scan period, t _ k ∈ [1, d ∈ ]]，k∈[1,L_t]D represents the total number of beam directions of the nodes, L_tDenotes the number of beam directions in the scanning sequence in the t-th scanning period, t is 0,1,2, …, N_s-max，N_s-maxRepresents the maximum number of scan cycles;

step 2, calculating the length of the basic time slot of each beam direction specifically includes:

wherein l_{t_k}，t_k∈[1,d]，t∈[0,N_s-max]，k＝1,2,…,L_tThe length of a basic time slot in the k beam direction in a scanning sequence in the t scanning period; d is the total number of wave beam directions of the nodes; l₀Is a predefined unit reference time slot length; lambda belongs to [1.21.5 ]]Allocating coefficients for predefined time slots; n _ node_{t_k}，t_k∈[1,d]，t∈[0,N_s-max]，k＝1,2,…,L_tThe adjacent node number in the adjacent node table of the kth wave beam direction in the scanning sequence in the t-th scanning period;

preferably, the first beam direction in the scanning sequence in the t-th scanning period in step 3 is:

D_{t_1}，t_1∈[1,d]，t∈[0,N_s-max]d is the total number of node beam directions, N_s-maxThe maximum number of scanning cycles;

step 3, the current beam direction is: d_current；

Preferably, in step 4, the current beam direction is: d_current；

Step 4, calculating the total time slot length of the neighbor node discovery operation executed in the current beam direction specifically includes:

L_current＝n_current·l_current

wherein L is_currentThe total time slot length in the current beam direction; n is_currentThe number of basic time slots in the current beam direction; l_currentThe length of a basic time slot of the current beam direction;

preferably, in step 5, the current beam direction is: d_current；

Step 5, executing the neighbor node discovery operation by using the total time slot length determined in step 4, specifically:

for the current beam direction D_currentTotal execution duration of L_currentIncluding in particular n_currentSearching for each time slot with length of l_current；

The mode of each search randomly selects one of the following three modes to execute:

mode 1: in a basic time slot length l_currentContinuously sending hello information to finish one-time searching;

mode 2: in a basic time slot length l_currentContinuously receiving hello information to finish one-time searching;

mode 3: in a basic time slot length l_currentInternal dormancy to complete one search;

if the current beam direction D_currentThe successful reception of hello information sent by another new neighbor node in the time slot for receiving hello information indicates the current beam direction D_currentSuccessfully discovering the new neighbor node;

preferably, in step 6, the current beam direction is: d_current；

Step 6, updating the neighbor node table in the current beam direction specifically includes: will present beam direction D_currentAdding the information such as the ID number, azimuth angle and the like of the new neighbor node successfully found in the step 5 into the neighbor node table in the current beam direction;

step 6, the number of the basic time slots in the current beam direction is: n is_current；

Step 6, the total time slot length in the current beam direction is: l is_current；

Preferably, in step 7, the scanning sequence in the t-th scanning period is: s_t＝{D_{t_1},D_{t_2},...,D_{t_Lt}}；

Wherein S is_tDenotes the scanning sequence in the t-th scanning period, D_{t_k}Denotes the kth beam direction in the scan sequence in the t-th scan period, t _ k ∈ [1, d ∈ ]]，k∈[1,L_t]D represents the total number of beam directions of the nodes, L_tDenotes the number of beam directions in the scanning sequence in the t-th scanning period, t is 0,1,2, …, N_s-max，N_s-maxRepresents the maximum number of scan cycles;

the current beam direction in step 7 is: d_current；

Preferably, the step 8 of constructing the scan sequence in the t +1 th scan period specifically includes:

for the scanning sequence S in the t-th scanning period_tIn each beam direction, i.e. D_{t_k}，t_k∈[1,d]，k＝1,2,…,L_tThe following determination is performed:

if N _ node_{t_k}≥N_targetThen D is_{t_k}Not adding the scanning sequence in the t +1 th scanning period, i.e. S_(t+1)；

Otherwise, the beam direction is D_{t_k}Adding the scanning sequence in the t +1 th scanning period, i.e. S_(t+1)；

Wherein N is_targetTarget value, N _ node, representing neighbor discovery_{t_k}Indicates the number of adjacent nodes in the k beam direction adjacent node table in the scanning sequence in the t scanning period, wherein t is 0,1,2, …, N_s-max，N_s-maxThe maximum number of scanning cycles;

the invention has the following beneficial effects:

and each node continuously detects the actual situation of each beam direction in the process of executing the task of the adjacent node, and adaptively and dynamically adjusts the adjacent node discovery strategy based on the detection result. For the beam direction in which the neighbor node is easy to find, the probability that the neighbor node is dense in the effective coverage range is higher. Therefore, more resources are allocated to the beam direction by increasing the length of the basic time slot and the number of the basic time slots, so that enough number of adjacent nodes can be found as soon as possible, and the task of finding the adjacent nodes is further completed; on the contrary, for the beam direction in which the adjacent node is not easy to find, especially for the beam direction in which the adjacent node cannot be found for a long time, the resource allocation in the beam direction is gradually reduced through the self-adaptive adjustment of the time slot length and the time slot number, so that the efficient allocation and utilization of the limited resources are realized;

in addition, the time slot length of each wave beam direction of each node is self-adaptively changed, and the time slot lengths are different, so that the problem of 'transmission/reception' state synchronization between the nodes caused by the fixed time slot length in the traditional method can be avoided.

Drawings

FIG. 1 is a flow chart of a method of implementing the present invention.

Fig. 2 is a schematic diagram of network node initialization.

Fig. 3 is a schematic diagram of each beam direction adaptive base slot length.

Fig. 4 is a schematic diagram of the configuration of the initialization total time slot for each beam direction.

Fig. 5 is a schematic diagram of a scan sequence update.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in fig. 1, for a wireless ad hoc network based on directional antennas, the method for discovering a neighboring node of an adaptive timeslot according to the present invention includes the following steps:

step 1: for the wireless self-organizing network based on the directional antenna, each node calculates the total number of wave beam directions of the nodes according to the wave beam angle of the directional antenna, sets a target value and the maximum scanning period number found by adjacent nodes, and initializes a scanning sequence, an adjacent node table of each wave beam direction, the number of adjacent nodes in the adjacent node table of each wave beam direction and the number of basic time slots of each wave beam direction;

preferably, the beam angle of the directional antenna in step 1 is: θ is 45 °;

step 1, the total number of beam directions of the computing nodes is as follows: d is 360 DEG/theta is 8;

the beam direction in step 1 is: d_i，i＝1,2,…,8；

The target value found by the adjacent node in the step 1 is as follows: n is a radical of_target3, the specific meaning is as follows: when the number of the discovered neighboring nodes in a certain beam direction is greater than or equal to 3, the beam direction is determined that the number of the discovered neighboring nodes is enough to meet the communication requirement, and the neighbor node discovery operation can not be continuously performed on the direction any more;

step 1 the maximum number of scanning cycles is: n is a radical of_s-max100, its specific meaning is: when the total number of times that the node periodically traverses each beam direction reaches 100 times, even if a sufficient number of neighboring nodes are not found in some beam directions of the node, the neighboring node discovery operation of the node also needs to be finished;

the scanning sequence in the step 1 is as follows: s_tT is 0,1,2, …,100, which is initialized to S₀＝{D₁,D₂,…,D₈}；

Step 1, the neighbor node table of each beam direction is: node _ Table_i1,2, …,8, all initialized to null;

the number of the adjacent nodes in the adjacent node table in each beam direction in the step 1 is as follows: n _ node_i1,2, …,8, all initialized to 0;

step 1, the number of basic time slots in each beam direction is: n is_i1,2, …,8, all initialized to 6;

step 2: calculating the basic time slot length of each beam direction in the scanning sequence in the t-th scanning period;

the scanning sequence in the tth scanning period in the step 2 is as follows: s_t＝{D_{t_1},D_{t_2},...,D_{t_Lt}}；

Wherein S is_tDenotes the scanning sequence in the t-th scanning period, D_{t_k}Denotes the kth beam direction in the scan sequence in the t-th scan period, t _ k ∈ [1,8 ]]，k∈[1,L_t]，L_tDenotes the number of beam directions in the scanning sequence in the t-th scanning period, where t is 0,1,2, …, 100. For example, the scan sequence in the 1 st scan cycle is S₁＝{D₁,D₂,D₃,D₄,D₅,D₆,D₇,D₈}. The neighbor node over several cycles finds that the beam direction D is the same as before the 10 th scanning cycle₂And D₄It has been found that not less than N_targetThe scan sequence in the 10 th scan cycle is S if 3 neighbor nodes₁₀＝{D₁,D₃,D₅,D₆,D₇,D₈}；

Step 2, calculating the length of the basic time slot of each beam direction specifically includes:

wherein l_{t_k}，t_k∈[1,8]，t∈[0,100]，k＝1,2,…,L_tThe length of a basic time slot in the k beam direction in a scanning sequence in the t scanning period; d is the total number of the wave beam directions of the node 8; l₀For a predefined unit reference slot length, in the present embodiment, take l₀＝10ms；λ∈[1.21.5]A coefficient is allocated to a predefined timeslot, and in the present embodiment, λ is 1.2; n _ node_{t_k}，t_k∈[1,8]，t∈[0,100]，k＝1,2,…,L_tThe number of adjacent nodes in the adjacent node table in the k wave beam direction in the scanning sequence in the t scanning period.

It can be seen that, at the initial time (before the 1 st scanning period starts), the number of neighbor nodes N _ node in the neighbor node table is determined by the number of neighbor nodes in each beam direction_iI is initialized to 0, so the basic slot length l of each beam direction_iUnit base time slot length l, i being equal to 1,2, …,8, each being one time₀The calculation process is as follows, 10 ms:

with the continuous execution of the neighbor node discovery operation, the neighbor node table of each beam direction is updated (i.e. the number of neighbor nodes N _ node in the neighbor node table of each beam direction is updated_iI is updated to 1,2, …, 8), the basic slot length l for different beam directions_iWill also change adaptively according to the following rules (schematic diagram shown in fig. 3):

firstly, for the wave beam direction (N _ node) with more adjacent nodes found in the current adjacent node table_iLarger value), will have a longer base slot length value (i.e. /) than other beam directions_i) This also means that such beam directions are subsequently performed by the neighboring nodesMore resources will be allocated during the discovery operation;

for the wave beam direction (N _ node) with less number of found neighbor nodes in the current neighbor node list_iSmaller value), less and less resources are allocated to carry out subsequent neighbor node discovery operation;

and step 3: taking a first beam direction in a scanning sequence in the t-th scanning period as a current beam direction;

step 3, the first beam direction in the scanning sequence in the t-th scanning period is: d_{t_1}，t_1∈[1,8]，t∈[0,100]；

Step 3, the current beam direction is: d_current；

And 4, step 4: calculating the total time slot length of the neighbor node discovery operation executed in the current beam direction;

step 4, the current beam direction is: d_current；

In this embodiment, the number n of basic slots in each beam direction_iI is 1,2, …, and 8 are all initialized to 6, that is, the total time slots of each beam direction at the initial time are all composed of 6 respective basic time slots, as shown in fig. 4;

step 4, calculating the total time slot length of the neighbor node discovery operation executed in the current beam direction specifically includes:

L_current＝n_current·l_current

wherein L is_currentThe total time slot length in the current beam direction; n is_currentThe number of basic time slots in the current beam direction; l_currentThe base slot length for the current beam direction. For example, the current scan cycle is 10 th (i.e. t is 10), and the current scan sequence is S₁₀＝{D₁,D₃,D₅,D₆,D₇,D₈D, the current beam direction_currentFor a scanning sequence S₁₀In a first beam direction, i.e. D_current＝D₁. If the current beam direction D₁Number of basic time slots n₁Base slot length l 6₁10ms, then the current beam direction D_current＝D₁The total time slot length of the upper execution neighbor node discovery operation is 60 ms;

and 5: for the current beam direction, performing neighbor node discovery operation by adopting the total time slot length determined in the step 4;

step 5, the current beam direction is: d_current；

Step 5, executing the neighbor node discovery operation by using the total time slot length determined in step 4, specifically:

for the current beam direction D_currentTotal execution duration of L_currentIncluding in particular n_currentSearching for each time slot with length of l_current；

The mode of each search randomly selects one of the following three modes to execute:

mode 1: in a basic time slot length l_currentContinuously sending hello information to finish one-time searching;

mode 2: in a basic time slot length l_currentContinuously receiving hello information to finish one-time searching;

mode 3: in a basic time slot length l_currentInternal dormancy to complete one search;

if the current beam direction D_currentThe successful reception of hello information sent by another new neighbor node in the time slot for receiving hello information indicates the current beam direction D_currentSuccessfully discovering the new neighbor node;

for example, for the current beam direction D_current＝D₁If its number of basic slots is n₁Base slot length l 6₁10ms, total slot length L₁For the current beam direction D60 ms₁And performing neighbor node discovery operation with the total time length of 60ms, wherein the total time comprises 6 times of searching, the length of each searching is 10ms, and the searching mode of each searching is random 'sending 10ms hello signals', 'receiving 10ms hello signals' and 'sleeping 10 ms'. For example, the current beam direction D₁Performed 60mAn example of an s-neighbor discovery operation is shown in table 1:

TABLE 1 Current Beam Direction D₁Performing operations within a 60ms neighbor discovery total slot

Step 6: if the current beam direction successfully finds a new neighbor node in the step 5, updating the neighbor node table of the current beam direction, adding 1 to the number of basic time slots of the current beam direction, and then jumping to the step 4 to recalculate the total time slot length of the current beam direction and re-execute the neighbor node finding operation; if no new neighbor node is found in the current beam direction in step 5, executing step 7;

step 6, the current beam direction is: d_current；

Step 6, updating the neighbor node table in the current beam direction specifically includes: will present beam direction D_currentAdding the information such as the ID number, azimuth angle and the like of the new neighbor node successfully found in the step 5 into the neighbor node table in the current beam direction;

step 6, the number of the basic time slots in the current beam direction is: n is_current；

Step 6, the total time slot length in the current beam direction is: l is_current；

For example, for the current beam direction D_current＝D₁Number of basic slots n₁Base slot length l 6₁10ms, total slot length L₁60ms, then in step 5 a neighbor discovery operation has been performed for it for a total duration of 60 ms:

if current beam direction D_current＝D₁If a new neighbor Node is successfully found in step 5, the found new neighbor Node ID number, azimuth angle, etc. information is added to the neighbor Node Table (i.e., Node _ Table) in the current beam direction_current＝Node_Table₁) And for the current beam direction D_current＝D₁Number of basic time slots n₁Adding 1, i.e. n_current＝n₁7. Then, jump to step 4 for the current beam direction D_current＝D₁The total slot length is recalculated and the neighbor discovery operation is re-performed. It is worth noting that now for the current beam direction D_current＝D₁The number of the basic time slots adopted when the total time slot length is recalculated should be the number of the basic time slots added with 1, namely n_current＝n₁＝7；

If current beam direction D_current＝D₁If the new neighbor node is not successfully found in step 5, the operation of updating the parameters and repeatedly finding the neighbor node is not performed, and the process jumps to step 7;

and 7: taking the next beam direction in the scanning sequence in the t-th scanning period as the current beam direction, and repeatedly executing the steps 4 to 6 until all beam directions in the scanning sequence in the t-th scanning period are traversed;

preferably, in step 7, the scanning sequence in the t-th scanning period is: s_t＝{D_{t_1},D_{t_2},...,D_{t_Lt}}；

Wherein S is_tDenotes the scanning sequence in the t-th scanning period, D_{t_k}Denotes the kth beam direction in the scan sequence in the t-th scan period, t _ k ∈ [1,8 ]]，k∈[1,L_t]，L_tRepresents the number of beam directions in the scanning sequence in the t-th scanning period, wherein t is 0,1,2, …, 100;

the current beam direction in step 7 is: d_current；

For example, the current scan cycle is 10 th (i.e. t is 10), and the current scan sequence is S₁₀＝{D₁,D₃,D₅,D₆,D₇,D₈}, current beam direction D_current＝D₁Failing to discover a new neighbor successfully in step 6, the sequence S will be scanned₁₀Is located at D₁The next beam direction thereafter (i.e. beam direction D)₃) As the current beam direction, i.e. order D_current＝D₃And then repeating the steps 4 to 6 untilUntil the current scanning sequence S is traversed₁₀In the last beam direction D₈；

And 8: constructing a scanning sequence in the t +1 th scanning period;

step 8, constructing a scanning sequence in the t +1 th scanning period specifically includes:

for the scanning sequence S in the t-th scanning period_tIn each beam direction, i.e. D_{t_k}，t_k∈[1,8]，k＝1,2,…,L_tThe following determination is performed:

if N _ node_{t_k}≥N_targetWhen 3, then D_{t_k}Not adding the scanning sequence in the t +1 th scanning period, i.e. S_(t+1)；

Otherwise, the beam direction is D_{t_k}Adding the scanning sequence in the t +1 th scanning period, i.e. S_(t+1)；

Wherein N is_targetN _ node, which is the neighbor discovery target value preset in step 1, is set to 3_{t_k}Representing the number of adjacent nodes in a k beam direction adjacent node table in a scanning sequence in a t scanning period, wherein t is 0,1,2, … and 100;

for example, the current scan cycle is 10 th (i.e. t is 10), and the current scan sequence is S₁₀＝{D₁,D₃,D₅,D₆,D₇,D₈}. One by one judgment S₁₀Whether the number of neighbor nodes in the neighbor node table per beam direction is greater than or equal to a target value of 3. Suppose a scan sequence S₁₀Beam direction D in₁、D₅、D₆Satisfy the requirement that the number of the adjacent nodes in the adjacent node table is more than or equal to 3, namely N _ node₁≥3、N_node₅Not less than 3 and N _ node₆Not less than 3, the scanning sequence of the 11 th scanning period is S₁₁＝{D₃,D₇,D₈}；

And step 9: if the scanning sequence in the t +1 th scanning period is empty, the adjacent node discovery process is finished; otherwise, repeating the steps 2 to 8 until the current scanning period number reaches the maximum scanning period number N_s-maxThe neighbor discovery process ends 100.