CN101895952B - Multi-route establishment method and parallel data transmission method of wireless sensor network - Google Patents

Abstract

The invention provides a low-delay transmission based multi-route establishment method and a multi-route parallel data transmission method of a wireless sensor network. The multi-route establishment method comprises the following steps: judging whether existing routes arriving at the destination node exist by a forwarding node; retaining the existing routes and carrying out bidirectional route confirmation if the existing routes exist; further judging whether the new routes exist if the existing routes do not exist; and further establishing multiple routes. The data transmission method comprises the following steps: selecting a plurality of routes containing least nodes from a plurality of established routes and simultaneously transmitting data; a source node detecting the state of each route and transmitting the data packet to be transmitted to a destination node along the route which is free in advance until all the data are transmitted. The two methods of the invention reduce the data transmission time and realize low-delay transmission of the data from the source node to the destination node.

Description

Multi-route establishment method and parallel data transmission method of wireless sensor network

technical field

The present invention relates to a multi-routing establishment method of a wireless sensor network and a parallel data transmission method, more specifically, to a multi-routing method for low-delay transmission of a wireless sensor network implemented at the network layer, and a method utilizing the above-mentioned A method for parallel transmission of data by multiple routes.

Background technique

The wireless sensor network deploys nodes with perception capabilities in a distributed manner in places that need to be sensed or monitored, and the physical quantities that need to be sensed or monitored are usually transmitted to the aggregation node in a wireless and multi-hop manner, thereby realizing wireless monitoring of the surrounding environment. Short-range wireless communication technology for perception purposes.

The core of wireless sensor network technology is the design of communication protocol stack. At present, most of the communication protocol stacks for specific applications both in the world and in China are designed based on the combination of IEEE 802.15.4 standard and ZigBee standard. The IEEE 802.15.4 standard is a protocol stack design corresponding to the physical layer and MAC layer of wireless sensors; and the ZigBee standard is a protocol stack design corresponding to the network layer and application layer. Among them, the role of the network layer protocol stack is to establish a network, provide management mechanisms for devices to join and leave the network, route discovery and route maintenance, discovery of one-hop neighbors and storage of adjacent node information, mechanisms for network layer data transmission, etc. .

Among them, the existing route discovery and route maintenance, the discovery of one-hop neighbors, and the mechanism of data transmission all support single-route establishment and single-route data transmission, because this can keep the nodes in the current active route The nodes in the currently active route remain in a dormant state, thereby saving the power consumption of the nodes and improving the service life of the nodes. Although the forwarding node between the source node and the destination node also saves multi-route information, this is to establish the latest route as soon as possible when the current route fails. In essence, it is still a single-route data transmission mode. When the number of forwarding nodes between the source node and the destination node is large, the network transmission delay will be very large, which cannot meet the low-latency transmission requirements of some application scenarios, such as intrusion detection, alarm data transmission, etc. It is difficult to meet its low-latency, real-time data transmission requirements.

Contents of the invention

In order to overcome the disadvantages of the above-mentioned technical problems, the present invention provides a multi-routing establishment method for wireless sensor network low-latency transmission realized at the network layer and a parallel data transmission method based on the multi-routing.

In the wireless sensor network multi-routing establishment method of the present invention, the wireless sensor network adopts a response mode to establish a transmission mode of the network layer, and its special feature is that the multi-routing establishment method includes the following steps:

a. The source node that needs to send data sends a routing request command to the destination node to the forwarding nodes around it;

b. The forwarding node judges whether there is an existing route to the destination node; if there is an existing route, then perform step c; if there is no existing route, then perform step g;

c. Retain the existing route judged as part of the multi-routing from the source node to the destination node; the forwarding node that executes the judgment sends a routing response command to its upper node for two-way routing confirmation; then, execute the following Step d;

d. the forwarding node judges whether there is a new route to the destination node; if it is judged that there is a new route, then step e is executed; if it is judged that there is no new route, then step f is executed;

e. The new route is retained as part of the multi-route from the source node to the destination node;

f. Cancel the establishment of other new routes for the forwarding node, and make a next-level routing request;

g. the forwarding node judges whether there is a new route to the destination node; if it is judged that there is a new route, then step h is executed; if it is judged that there is no new route, then step i is executed;

h. The new route is retained as part of the multi-route from the source node to the destination node;

i. Cancel the establishment of the route to the forwarding node.

The forwarding nodes mentioned in the above method are the nodes around the source node, that is, the nodes that directly communicate with the source node. In the process of route establishment, after the forwarding nodes around the source node send the route request command to the destination node, the forwarding node first judges whether there is an existing route, and then judges whether there is a new route. Establishing multiple routes between the source node and the destination node can realize low-latency transmission of data from the source node to the destination node.

Further, in the wireless sensor network multi-route establishment method of the present invention, the method for judging whether there is a new route in the forwarding node described in step d and step g includes the following steps:

1) The forwarding node sends a routing request command to the destination node to the next level of forwarding nodes around it;

2) Judging whether the forwarding node receives the routing response command of the next-level node within the preset time interval, if it receives the routing response command within the preset time interval, then there is a route to the destination node; If no routing response command is received within the preset time interval, there is no route to the destination node;

The method for establishing the route from the forwarding node to the destination node between the source node and the destination node is the same as the method for establishing the route from the source node to the destination node described in claim 1 .

The above-mentioned further limitation of the technical solution provides a method for judging whether the forwarding node has a new route, so that the method for establishing the route from the source node to the destination node is more perfect. In the case that there are many forwarding nodes between the source node and the destination node, it is stipulated that the establishment method of the route from the forwarding node to the destination node between the source node and the destination node is the same as the establishment method of the route from the source node to the destination node, and can be based on the same A method to establish multiple routes between the source node and the destination node. During the establishment of the route from the source node to the destination node, the source node sends a route request command to its surrounding forwarding nodes. The forwarding node first judges whether there is an existing route, and then sends a route request command to its subordinate forwarding nodes; The node first judges whether there is a route, and then sends a route request command to its subordinate forwarding node, and proceeds in this way; until the route request command is sent to the destination node or a forwarding node that has no connection with the destination node; when the destination node After receiving the routing request command, send the routing response command directly to the last forwarding node in the route, and then the forwarding node sends the routing response command to the upper forwarding node one by one; if the node that finally receives the routing request command is not in contact with the destination node Forwarding node, the destination node will not send a routing reply command to the forwarding node, and the forwarding node will not send a routing reply command to its superior node.

Further, in the wireless sensor network multi-routing establishment method of the present invention, if the forwarding node between the source node and the destination node is the destination node, the corresponding forwarding node directly sends a routing response command to its upper node, without It is judged whether there is a route to the destination node.

Further, wireless sensor network multi-routing establishment method of the present invention, the command format of network layer in the described multi-routing establishment method is established based on ZigBee network layer command, bit 6 and bit 7 in the frame control format of ZigBee network layer command The combination value of is defined as the routing discovery flag, and the combination of bit 13, bit 14 and bit 15 in the frame control format of the ZigBee network layer command is defined as the routing number of the multi-routing found; the bit 0 in the routing request command format is defined as It is a routing request flag, which is used to mark whether it is a single routing request or a multi-routing request; the combination of bit 0, bit 1 and bit 2 of the command selection domain field in the routing response command is defined as the routing number, which is used to indicate the current routing response Which route is returned from. Bit 6 and bit 7 in the frame control format, bit 13, bit 14 and bit 15 in the frame control format, bit 0 in the routing request command format, and bit 0 in the command selection domain field in the routing response command , bit 1 and bit 2 are all reserved bits of existing commands, define these undefined reserved bits, and the definitions of other bits remain unchanged, and no new commands are added, which ensures good compatibility with Compatibility with existing ZigBee standards.

Further, in the wireless sensor network multi-route establishment method of the present invention, when the combination of bit 6 and bit 7 in the frame control format is 00, 01, 10 or 11, the meanings are respectively prohibiting route discovery and allowing route discovery , allowing multiple routes to be discovered and reserved; bit 0 in the route request command format is 1 to indicate a multi-route request, and 0 to indicate a single-route request.

The multi-routing parallel data transmission method based on the wireless sensor network of the present invention may wish to set the total number of routes established by the source node to the destination node as m, and the data packets to be transmitted are n, and its special features are: The described parallel data transmission method comprises the following steps:

A. Select j routes containing the least number of nodes from m routes;

B. Send the No. 1 data packet to the No. j data packet in the n data packets to be sent through the No. 1 route to the No. j route respectively;

C. The source node detects the status of route 1 to route j, detects which route is free first, and sends the data packet to be sent to the destination node along the route that is free first;

D. Repeat step C until all n data packets are sent;

E. The destination node splices the received n data packets in order according to the package number, and then restores the data to be sent by the source node.

Compared with the existing transmission methods, the above-mentioned data transmission method based on the multi-routing of the wireless sensor network has the advantage of low delay. Because the data transmission in the existing wireless sensor network only transmits data through one route, but the data transmission method based on multiple routes in the wireless sensor network in the present invention relies on multiple routes for data transmission, for the same number of waiting For data transmission, the data transmission method of the present invention can be used to complete data transmission in less time, so that it can meet many occasions requiring low-latency transmission.

Further, in the wireless sensor network multi-routing data transmission method of the present invention, it is assumed that N _max is the number of nodes included in the longest route among the m routes, and the maximum average transmission delay time allowed from the source node to the destination node is T, The maximum processing delay time for each forwarding node to process a data packet is τ _max , which is characterized in that: the value of j can be determined by the following formula:

$\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Greater\; Equal;</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}$

After calculation through the above formula, if the value of the right end of the above inequality is less than the value of m, then j takes the smallest integer value that satisfies the conditions of the above inequality; if the value of the right end of the above inequality is greater than or equal to the value of m, then the value of j is m. The above inequality gives the value calculation method of the number j of routes from the source node to the destination node. The route obtained through the above formula calculation can realize the low delay requirement of data transmission during data transmission.

The beneficial effects of the present invention are: using the multi-route establishment method of the present invention, multiple routes can be established between the source node and the destination node, so that the data from the source node to the destination node can be transmitted in parallel along multiple routes, It is beneficial to realize low-latency transmission of data; in the routing establishment method of the present invention, the establishment of the route from the forwarding node to the destination node includes two establishment processes of an existing route and a new route, which makes the establishment process of the route more convenient. In the data parallel transmission method based on multiple routes of the wireless sensor network of the present invention, the data can be transmitted simultaneously through multiple selected routes, realizing the low-delay transmission of data from the source node to the destination node.

Description of drawings

Fig. 1 is the schematic diagram of multi-route establishment process of the present invention;

Fig. 2 is the schematic diagram of the principle of the present invention utilizing multiple routes to carry out data parallel transmission;

Fig. 3 is a program principle diagram of the multi-routing establishment process of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

The solid line arrow RREQ shown in Fig. 1 and Fig. 2 indicates a routing request command, and the dotted line arrow RREP indicates a routing reply command.

Fig. 1 and Fig. 3 have respectively provided the schematic diagram of route establishment process of the present invention and the procedure figure that route establishes, and Fig. 3 has generally provided the flow chart of route establishment process, can draw that the process of route establishment comprises following by Fig. 3 Steps: a. The source node that needs to send data sends a route request command to the forwarding node around it to the destination node; b. The forwarding node judges whether there is an existing route to the destination node; if there is an existing route, Then execute step c; if there is no existing route, then execute step g; c. retain the existing route judged as part of the multi-routes from the source node to the destination node; The first-level node sends a route response command to confirm the two-way route; then, perform the following step d; d. The forwarding node judges whether there is a new route to the destination node; if it is judged that there is a new route, then execute step e; If it is judged that there is no new route, then step f is performed; e. the new route is reserved as part of the multi-route from the source node to the destination node; f. cancel the establishment of a new route for the forwarding node, and carry out the routing of the next level Request; g. the forwarding node judges whether there is a new route to the destination node; if it is judged that there is a new route, then execute step h; if it is judged that there is no new route, then execute step i; h. The other part of the multi-route from the source node to the destination node is reserved; i. Cancel the establishment of the route to the forwarding node. When the forwarding node between the source node and the destination node is the destination node, the corresponding forwarding node directly confirms the routing response command to its superior node. The judging method of whether there is a new route in the forwarding node described in step d and step g comprises the following steps: 1) the forwarding node sends a routing request command to the destination node to its surrounding subordinate forwarding nodes; 2) judges whether the forwarding node is in Receive the routing response command of the next-level node within the preset time interval, if the routing response command is received within the preset time interval, there is a route to the destination node; if within the preset time interval Have not received the routing response command, then there is no route to the destination node; the method for establishing the route from the forwarding node to the destination node between the described source node and the destination node is the same as that described in claim 1 from the source node to the destination node Routing is established in the same way.

The method for establishing routes described above generally provides a method for establishing multiple routes from a source node to a destination node. The process of establishing routes will be specifically described below in conjunction with FIG. 1 .

As shown in Figure 1, there are 9 nodes in Figure 1, among which, the No. 1 node is the source node, which is used to initiate the initial routing request command; the No. 6 node is the destination node, which can only initiate the routing response command; the remaining nodes are A forwarding node from a source node to a destination node.

When establishing a route from the source node to the destination node, first the source node 1 sends a routing request command RREQ to the surrounding node 2 and node 8. When the node 8 receives this command, it first checks whether it has reached the node 6 The existing route of the node exists; since there is no existing route, the No. 8 node continues to send a route request command to the No. 9 node to see if there is a new route; because the current No. 9 node does not have an existing route to the destination node, Node 9 continues to send the routing request command RREQ forward for pathfinding; because destination node 6 cannot send the routing response command RREP to node 9, node 9 cannot receive the routing response command RREP within the preset time interval, so Node 9 also cannot send the routing response command RREP to node 8 for two-way routing confirmation; furthermore, node 1 cannot receive the routing response command RREP from node 8 within the preset time interval, and it will cancel the routing response command RREP of node 8. The establishment of the route from the node to the destination node 6.

Assuming that 2-3-5-6 is the established route from node 2 to destination node 6, when node 2 receives the routing request command RREQ from source node 1, whether the forwarding node 2 has an existing route There is a route to judge, because there is an existing route 2-3-5-6, the node 2 sends a routing response command RREP to the source node 1, so that the two-way route from node 1 to node 2 is established, At the same time, the existing 2-3-5-6 route is reserved and stored as a part of the route from the source node 1 to the destination node 6 . Then, the No. 2 node continues to send the routing request command RREQ forward to find out whether there are other new routes to the No. 6 destination node. As shown in Figure 1, 2-4-7-6 is from No. 2 node to No. 6. No. 6 destination node's new route, and No. 4 and No. 7 nodes do not have existing routes to destination node 6, so No. 2 node will receive the routing reply command RREP sent back from No. 4 node, then 2- 4-7-6 This new route will be reserved and stored as another part of the route from source node 1 to destination node 6.

Assuming that there is no existing route from node 2 to destination node 6, node 2 initiates a route request RREQ to node 3 and node 4 at the same time, and routes from node 3 and node 4 within a preset time interval Return a routing response command RREP, so that node 2 will receive a routing response command RREP from node 3 and node 4 within a preset time interval, and node 2 will reach node 3 and node 4 All links are reserved and stored as newly found bidirectional routes.

The route establishment process of other forwarding nodes between the source node 1 and the destination node 6 is the same. After such a route establishment process, multiple routes from the source node to the destination node are established.

Below in conjunction with Figure 2, the method for parallel data transmission based on the established multi-routes is described:

As shown in Figure 2, it is advisable to assume that the total number of routes established from the source node to the destination node is m, and the data to be transmitted includes n data packets, and the parallel transmission of data is performed according to the following steps:

First, determine j (j≤m) routes for data transmission according to the following inequality (1);

$\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; \&Greater\; Equal;</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Among them, N _max is the number of nodes contained in the longest route among the m routes, T is the maximum average transmission delay time allowed, and τ _max is the maximum processing delay time for each node to process a data packet. When the value at the right end of inequality (1) is less than m, j takes the smallest integer value that satisfies inequality (1); when the value at the right end of inequality (1) is greater than or equal to m, the value of j takes m.

Of course, for the sake of simplicity, the determination of the value of the number of routes j may also select the j route containing the least number of nodes among the m routes for data transmission.

Then, send the No. 1 data packet to the No. j data packet in the n packets of data packets to be sent to the destination node along the No. 1 route to the No. Perform detection to determine which route is free first, and send the data packets to be sent to the destination node along the first free route until all n data packets are sent.

Finally, the destination node splices the received n data packets in order according to the package numbers, and then restores the data to be sent by the source node.

This can not only ensure that all n data packets to be transmitted are transmitted to the destination node within a specified time, but also make the total node energy consumed by data transmission not too large.

Correspondingly, if certain parameters are set, the mathematical expression of the average transmission delay time of the network using multiple routes for data transmission can also be given. Assume that there are m routes from the source node to the destination node, and the current source node selects j routes among them for data transmission from the source node to the destination node. There are n data packets to be sent by the source node, and route 1 includes N ₁ node, No. 2 route contains N ₂ nodes, ..., No. j route contains N _j nodes, the processing delay of node i is τ _i , and assuming that the number of data packets sent through each route is equal, then send n The average network delay time required by a data packet can be expressed by the following formula (2), where E represents the mean value,

$\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; j</span>}}\mathrm{<span\; class="notranslate">\; E.</span>}<span\; class="notranslate">\; [</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="1"\; label="N"\; filenames="HSA00000192862400012.png"\; state="\{\{state\}\}">N</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; ,</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="N"\; filenames="HSA00000192862400012.png"\; state="\{\{state\}\}">N</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; ,</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; ,</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; ]</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

The above expression can also be expressed as

For the case of single-route transmission, if the route l (1≤l≤j) is selected for data packet transmission, and the route contains N _l nodes, the network delay required to send n data packets The time can be expressed by the following equation (3),

$\mathrm{<span\; class="notranslate">\; no</span>}\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

则(2)式可以表示为(4)式，If the mean in (2) is

Then (2) formula can be expressed as (4) formula,

$\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; j</span>}}\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

By comparing (3) and (4), it can be obtained that the greater the number of selected routes j, the less the average network transmission delay time used for data transmission from the source node to the destination node. The larger the number j of selected routes is, the more forwarding nodes will participate in data transmission, and the more energy will be consumed.

The present invention has also set up the command format of the network layer based on the network layer order of ZigBee, and it has utilized the reserved bit of existing format, and the definition of other each each remains unchanged, does not increase new order, has realized and Compatibility with existing ZigBee standards.

As shown in table 1, the combination value 10 of bit 6 and bit 7 in the frame control format of ZigBee network layer command is defined as allowing multi-route discovery flag, and the combination definition of bit 6 and bit 7 is as shown in table 2; ZigBee The combination of bit 13, bit 14 and bit 15 in the frame control format of the network layer command is defined as the routing number of the discovered multi-routing.

Table 1 frame control format (bit)

Definition of 6 and 7 bits in the frame control format of Table 2

Discover the value of the routing field Expressed meaning 00 Disable route discovery 01 Allow route discovery 10 Allow multiple route discovery 11 reserve

Define bit 0 in the routing request command format as a routing request flag, which is used to mark whether it is a single-path request or a multi-path request. Bit 0 is 1 to indicate a multi-routing request, and bit 0 is 0 to indicate a single-routing request, as shown in Table 3 ; The combination of bit 0, bit 1 and bit 2 of the command selection domain field in the routing response command is defined as the routing number, which is used to indicate from which route the current routing response is returned, as shown in Table 4.

Table 3 routing request command format (bits)

0 1-2 3-4 5 6 7 Single (multiple) routing requests reserve many to one Destination IEEE address Multiple casts reserve

Table 4 command selection domain field format (bits)

Claims (7)

1. a wireless sensor network multi-routing method for setting up, the wireless sensor network adopts the response mode to set up the transmission mode of the network layer, it is characterized in that, the described multi-routing method for setting up comprises the following steps: a. The source node that needs to send data sends a routing request command to the forwarding nodes around it to the destination node; b. The forwarding node judges whether there is an existing route to the destination node; if there is an existing route, then perform step c; if there is no existing route, then perform step g; c. Reserving the judged existing route as part of the multi-routing from the source node to the destination node; the forwarding node that executes the judgment sends a route reply command to its upper-level node for two-way route confirmation; then, perform the following steps d; d. The forwarding node judges whether there is a new route to the destination node; if it is judged that there is a new route, then execute step e; if it is judged that there is no new route, then execute step f; e. The new route is preserved as part of the multi-route from the source node to the destination node; f. Cancel the establishment of a new route for the forwarding node, and proceed to the next level of routing request; g. The forwarding node judges whether there is a new route to the destination node; if it is judged that there is a new route, then execute step h; if it is judged that there is no new route, then execute step i; h. The new route is retained as another part of the multi-route from the source node to the destination node; i． Cancel the establishment of the route to the forwarding node. 2. The wireless sensor network multi-routing establishment method according to claim 1, is characterized in that: whether the forwarding node described in the step d and the step g has the judging method of new route and comprises the following steps: 1) The forwarding node sends a routing request command to the destination node to the surrounding next-level forwarding nodes; 2) Determine whether the forwarding node receives the routing response command from the next-level node within the preset time interval. If it receives the routing response command within the preset time interval, there is a route to the destination node; If no routing response command is received within the preset time interval, there is no route to the destination node; The method for establishing the route from the forwarding node to the destination node between the source node and the destination node is the same as the method for establishing the route from the source node to the destination node described in claim 1 . 3. The wireless sensor network multi-routing establishment method according to claim 2 is characterized in that: if the forwarding node between the described source node and the destination node is the destination node, then the corresponding forwarding node directly forwards to its upper level The node sends the routing response command without judging whether there is a route to the destination node. 4. according to claim 1 and 2 described wireless sensor network multi-route establishment methods, it is characterized in that: the command format of network layer in the described multi-routing establishment method is based on ZigBee network layer order establishment, the frame of ZigBee network layer order The combined value of bit 6 and bit 7 in the control format is defined as the routing discovery flag, and the combination of bit 13, bit 14 and bit 15 in the frame control format of the ZigBee network layer command is defined as the routing number of the multi-routing found; Bit 0 in the route request command format is defined as a route request flag, which is used to mark whether it is a single route request or a multi-route request; the combination of bit 0, bit 1 and bit 2 of the command selection domain field in the route response command is defined as a route The number is used to indicate which route the current route response is returned from. 5. The wireless sensor network multi-routing establishment method according to claim 4, is characterized in that: when the combination of bit 6 and bit 7 in the described frame control format is 00, 01, 10 or 11, the meanings represented are respectively Prohibit route discovery, allow route discovery, allow multi-route discovery, and reserve; when bit 0 in the route request command format is 1, it indicates a multi-route request, and when it is 0, it indicates a single-route request. 6. A multi-routing parallel data transmission method of the wireless sensor network based on the multi-routing establishment method described in claim 1, may wish to set up in claim 1 from the source node to the destination node total routing number is m , there are n data packets to be transmitted, characterized in that: the parallel data transmission method comprises the following steps: A． Select j routes containing the least number of nodes from m routes; B． Send the No. 1 data packet to the No. j data packet in the n data packets to be sent through the No. 1 route to the No. j route respectively; C． The source node detects the status of route 1 to route j, detects which route is free first, and sends the data packet to be sent to the destination node along the route that is free first; D． Repeat step C until all n data packets are sent; E． The destination node splices the received n data packets in order according to the package number, and then restores the data to be sent by the source node. 7. multi-route parallel data transmission method according to claim 6, assuming that N _max is the number of nodes included in the longest route in m routes, the maximum average transmission delay time allowed from source node to destination node is T, every The maximum processing delay time for each forwarding node to process a data packet is τ _max , which is characterized in that: the value of j can be determined by the following formula:

After calculation through the above formula, if the value of the right end of the above inequality is less than the value of m, then j takes the smallest integer value that satisfies the conditions of the above inequality; if the value of the right end of the above inequality is greater than or equal to the value of m, then the value of j is m.

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