CN111343687B

CN111343687B - Network data transmission method and device based on multi-relay cooperation and electronic equipment

Info

Publication number: CN111343687B
Application number: CN202010123809.9A
Authority: CN
Inventors: 王峰; 王金乐; 李远军
Original assignee: Dalian Linktech Infosystem Co ltd
Current assignee: Dalian Linktech Infosystem Co ltd
Priority date: 2020-02-27
Filing date: 2020-02-27
Publication date: 2021-07-16
Anticipated expiration: 2040-02-27
Also published as: CN111343687A

Abstract

The application discloses a network data transmission method, a device and electronic equipment based on multi-relay cooperation, wherein the method is suitable for any node in a communication network, the node is provided with a multi-relay cooperation forwarding control channel and a plurality of multi-relay cooperation forwarding service channels, and the method comprises the following steps: transmitting first control data to each other node in a communication network by using a multi-relay cooperative forwarding control channel of a current node, so that each other node establishes a gradient table of other nodes according to the received first control data; receiving second control data transmitted by each other node by using the multi-relay cooperative forwarding control channels of the other nodes, and establishing a gradient table of the current node according to the second control data; the gradient table of the current node is used for determining whether to forward the service data corresponding to the received service request under the condition that the second control data received by the current node contains the service application.

Description

Network data transmission method and device based on multi-relay cooperation and electronic equipment

Technical Field

The present application relates to the field of network communication technologies, and in particular, to a network data transmission method and apparatus based on multi-relay cooperation, and an electronic device.

Background

In mobile ad hoc networks, routing protocols can be divided into unicast routing and multicast routing, according to the forwarding mode. Among them, unicast routing is the most dominant type of routing protocol for ad hoc networks. According to the route triggering principle, the unicast route can be divided into 3 types of a prior-check type route protocol, a reactive type route protocol and a mixed type route protocol.

In the multi-hop unicast and multicast transmission process of the mobile ad hoc network, no matter which routing protocol is used, nodes participating in transmission need to be determined through routing information, and corresponding resources are scheduled.

However, the route establishment and maintenance of the mobile ad hoc network generate non-negligible system overhead, which results in low data transmission efficiency in the network.

Disclosure of Invention

In view of this, the present application provides a network data transmission method, device and electronic device based on multi-relay cooperation, which includes:

a network data transmission method based on multi-relay cooperation is applicable to any node in a communication network, wherein the node is provided with a multi-relay cooperation forwarding control channel and a plurality of multi-relay cooperation forwarding service channels, and the method comprises the following steps:

transmitting first control data to each other node in the communication network by using a multi-relay cooperative forwarding control channel of a current node, so that each other node establishes a gradient table of the other node according to the received first control data, wherein a gradient between the other node and the current node in the gradient table of the other node is recorded as a current transmission hop count in the first control data;

receiving second control data transmitted by each other node by using a multi-relay cooperative forwarding control channel of the other node, and establishing a gradient table of the current node according to the second control data, wherein the gradient between the current node and the other nodes in the gradient table of the current node is recorded as the current transmission hop count in the second control data;

the current node's gradient table is used for determining whether to forward the service data corresponding to the received service request under the condition that the current node contains the service application in the received second control data;

the current node transmits service data corresponding to the service application to a next hop node under the condition that the sum of the first gradient and the second gradient is less than or equal to a third gradient in the service application;

the first gradient represents the hop count between the current node and a source node of the service application, the second gradient represents the hop count between the current node and a destination node, and the third gradient represents the hop count between the source node and the destination node.

Preferably, the method for establishing the gradient table of the current node according to the second control data includes:

obtaining a source node identifier and a current transmission hop count in the second control data, where the current transmission hop count is a number of nodes that the second control data is transmitted from a node corresponding to the source node identifier to the current node, and the current transmission hop count is greater than or equal to 1;

and recording the gradient between the node corresponding to the source node identification and the current node in the gradient table of the current node as the current transmission hop count.

Preferably, in the above method, if the current node is not the destination node of the node corresponding to the source node identifier, the method further includes:

adding 1 to the current transmission hop count in the second control data;

and transmitting the second control data to a next hop node of the current node in the communication network by using a current multi-relay cooperative forwarding control channel, so that the next hop node establishes a gradient table according to the received second control data.

Preferably, in the method, the transmitting, by the current node, service data corresponding to the service application to the next-hop node includes:

configuring time-frequency transmission parameters of a multi-relay cooperative forwarding service channel corresponding to a channel identifier in the service application of the current node;

and transmitting the service data corresponding to the service application to the next hop node of the current node by using the configured multi-relay cooperative forwarding service channel.

In the foregoing method, preferably, a first time slot of the current node when receiving the service data by using the multi-relay cooperative forwarding service channel is different from a second time slot of the current node when transmitting the service data by using the multi-relay cooperative forwarding service channel.

Preferably, in the above method, after the current node transmits the service data corresponding to the service application to the next hop node, the method further includes:

obtaining a service resource release request; the service resource release request is a request generated by a source node of the service application;

and responding to the service resource release request to release a multi-relay cooperative forwarding service channel corresponding to the channel identifier of the current node.

Preferably, in the method, if the service data corresponding to the service application is a broadcast service type, the method further includes:

under the condition that the data volume of the service data corresponding to the service application in the second control data is smaller than or equal to a preset threshold value, broadcasting to other nodes in the communication network by using a multi-relay cooperative forwarding control channel of the current node;

and under the condition that the data volume of the service data corresponding to the service application in the second control data is greater than a preset threshold, executing: and configuring time-frequency transmission parameters of a multi-relay cooperative forwarding service channel corresponding to the channel identifier in the service application of the current node.

Preferably, the method for transmitting the first control data to each other node in the communication network by using the multi-relay cooperative forwarding control channel of the current node includes:

obtaining a channel use right of a multi-relay cooperative forwarding control channel of the current node;

transmitting first control data to each other node in the communication network using the channel usage rights of the multi-relay cooperative forwarding control channel.

A network data transmission device based on multi-relay cooperation, which is applied to any node in a communication network, wherein the node has a multi-relay cooperative forwarding control channel and a plurality of multi-relay cooperative forwarding traffic channels, and the device comprises:

a sending unit, configured to transmit first control data to each other node in the communication network by using a multi-relay cooperative forwarding control channel of a current node, so that each other node establishes a gradient table of the other node according to the received first control data, respectively, where a gradient between the other node and the current node in the gradient table of the other node is recorded as a current transmission hop count in the first control data;

a receiving unit, configured to receive second control data transmitted by each of the other nodes using a multi-relay cooperative forwarding control channel of the other node;

a building unit, configured to build a gradient table of the current node according to the second control data, where a gradient between the current node and the other node in the gradient table of the current node is recorded as a current transmission hop count in the second control data;

the processing unit is used for determining whether to forward the service data corresponding to the received service request according to the gradient table of the current node under the condition that the received second control data contains the service application;

wherein the sending unit is further configured to: transmitting service data corresponding to the service application to a next hop node of the current node under the condition that the sum of the first gradient and the second gradient is less than or equal to a third gradient in the service application;

An electronic device, which is a node in a communication network, the node having a multi-relay cooperative forwarding control channel and a plurality of multi-relay cooperative forwarding traffic channels, the electronic device comprising:

a transmission interface, configured to transmit first control data to each other node in the communication network by using a multi-relay cooperative forwarding control channel of a current node, so that each other node establishes a gradient table of the other node according to the received first control data, respectively, where a gradient between the other node and the current node in the gradient table of the other node is recorded as a current transmission hop count in the first control data;

the transmission interface is further configured to receive second control data transmitted by each of the other nodes using the multi-relay cooperative forwarding control channel of the other node;

a processor, configured to establish a gradient table of the current node according to the second control data, where a gradient between the current node and the other node in the gradient table of the current node is recorded as a current transmission hop count in the second control data;

the processor is further configured to: determining whether to forward the service data corresponding to the received service request according to the gradient table of the current node under the condition that the received second control data contains the service application,

when the sum of the first gradient and the second gradient is less than or equal to a third gradient in the service application, transmitting service data corresponding to the service application to a next hop node of the current node by using the transmission interface;

According to the above scheme, in the network data transmission method, device and electronic device based on multi-relay cooperation provided by the application, the gradiometer is established on each node in the communication network, and the gradiometer comprises the hop count from each node to any other node, so that when the node needs to transmit the service data, whether the node forwards the service data is determined by judging the hop count, for example, the node only needs to forward the service data when the sum of the gradients respectively reaching the source node and the destination node is less than or equal to the gradient from the source node to the destination node, and thus, in the process of realizing forwarding the service data, the system overhead caused by establishing a route between the nodes is avoided, and the data transmission efficiency in the network is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a flowchart of a network data transmission method based on multi-relay cooperation according to an embodiment of the present application;

fig. 2 is a schematic diagram of node data transmission in a communication network according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a network data transmission apparatus based on multi-relay cooperation according to a second embodiment of the present application;

fig. 4 is a schematic structural diagram of an electronic device according to a third embodiment of the present application;

fig. 5-12 are diagrams illustrating various networks according to embodiments of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Referring to fig. 1, a flowchart is shown for implementing a network data transmission method based on multi-relay cooperation according to an embodiment of the present disclosure, where the method in this embodiment is applied to any node in a communication network, and each node in the communication network has one multi-relay cooperation forwarding control channel and multiple multi-relay cooperation forwarding traffic channels. The method in the embodiment is mainly used for reducing the system overhead caused by data transmission between nodes in the communication network so as to improve the efficiency of data transmission.

Specifically, the method in this embodiment may include the following steps:

step 101: and transmitting the first control data to each other node in the communication network by using the multi-relay cooperative forwarding control channel of the current node, so that each other node establishes a gradient table of other nodes according to the received first control data.

Specifically, in this embodiment, the current node, as a source node, broadcasts a control packet, that is, first control data, to the communication network by using its own multi-relay cooperative forwarding control channel, so that each of the other nodes receiving the first control data can establish its own gradient table according to the received first control data, that is, the number of hops between itself and the current node is recorded in the gradient table. For example, each other node in the communication network that receives the first control data records the current transmission hop count in the first control data as the gradient between the other node and the current node in its own gradient table, that is, each other node that receives the first control data records the gradient between the other node and the current node in its own gradient table as the current transmission hop count in the first control data.

It should be noted that the first control data broadcasted by the current node not only includes a transmission HOP count field, such as an HOP field, for recording the current transmission HOP count, but also includes identity information of a sending node corresponding to the first control data, that is, an identifier of a source node to which the first control data belongs, that is, a node identifier of the current node, where the current transmission HOP count refers to the number of nodes that are experienced between the source node to which the first control data belongs, that is, the current node, and other nodes that receive the first control data, and the transmission HOP count field for recording the current transmission HOP count is initially set to 1.

For example, the current transmission hop count between the first node receiving the first control data and the source node to which the first control data belongs is 1, the gradient between the node receiving the first control data and the source node to which the first control data belongs in the corresponding first node receiving the first control data is 1, the current transmission hop count between the second node receiving the first control data and the source node to which the first control data belongs is 2, the gradient between the node receiving the first control data and the source node to which the first control data belongs in the corresponding second node receiving the first control data is 2, and in the same way, each node receiving the first control data records the current transmission hop count in the first control data as the gradient between the node receiving the first control data and the current node in the respective gradient table.

Step 102: and receiving second control data transmitted by each other node by using the multi-relay cooperative forwarding control channel of the other node.

Wherein, like the current node, each other node in the communication network also broadcasts its own control packet, i.e. second control data, to each node in the communication network using its own multi-relay cooperative forwarding control channel, so that when the second control data is broadcasted to the current node, the current node receives the second control data broadcasted by each other node.

It should be noted that the execution sequence of step 101 and step 102 is not limited by the arrow sequence in the drawings, and step 102 and the subsequent steps may be executed first, and different schemes implemented by different execution sequences are also within the scope of the present application.

Step 103: and establishing a gradient table of the current node according to the second control data.

Wherein a gradient between the current node and the other nodes in the gradient table of the current node is recorded as a current transmission hop count in the second control data.

Specifically, in this embodiment, after the current node receives, as the destination node or the relay node, the second control data broadcast by the other nodes in the communication network through the own multi-relay cooperative forwarding control channel, the current node can establish its own gradient table according to the received second control data of each other node, that is, record the hop count between itself and each other node in the gradient table. For example, the current node in the communication network records the current transmission hop count in the second control data as the gradient between the current node and the other nodes to which the received second control data belongs in its own gradient table, that is, the gradient between the current node and the other nodes to which each second control data belongs is recorded as the current transmission hop count in the second control data in its own gradient table by the current node.

It should be noted that the second control data broadcast by other nodes not only includes a transmission hop count field for recording the current transmission hop count, but also includes identity information of a sending node corresponding to the second control data, that is, an identifier of a source node to which the second control data belongs, that is, a node identifier of the other node, where the current transmission hop count refers to the number of nodes experienced between the source node to which the second control data belongs, that is, the other node, and the current node that receives the second control data, and the transmission hop count field for recording the current transmission hop count is initially set to 1.

For example, the current transmission hop count between the current node as the first node that receives the second control data and the source node to which the second control data belongs is 1, the gradient between the current node in the corresponding gradient table of the current node and the source node to which the second control data belongs is 1, the current transmission hop count between the current node as the second node that receives the second control data and the source node to which the second control data belongs is 2, the gradient between the current node in the corresponding gradient table of the current node and the source node to which the second control data belongs is 2, and so on, the current node records the current transmission hop count in the second control data as the gradient between the node to which the second control data belongs and the current node in its own gradient table.

Based on the implementation, each node in the communication network broadcasts its own control packet, and then each node perfects its own gradient table according to the received control packet sent or forwarded by other nodes, and records the hop count between the node and other nodes in the gradient table as the gradient.

Correspondingly, the gradient table of the current node is used for determining whether to forward the service data corresponding to the received service request under the condition that the second control data received by the current node contains the service application.

That is to say, when each node in the communication network receives second control data sent or forwarded by another node, if the second control data includes a service application that characterizes the service data transmission performed by another node, at this time, the node that receives the second control data may determine whether to forward the service data corresponding to the service application according to each gradient recorded in its own gradient table.

Specifically, the current node transmits service data corresponding to the service application to the next hop node when the sum of the first gradient and the second gradient is less than or equal to a third gradient in the service application; the first gradient represents the hop count between the current node and the source node of the service application, the second gradient represents the hop count between the current node and the destination node, and the third gradient represents the hop count between the source node and the destination node.

Wherein, the service application is the content carried in the second control data, when the source node to which the second control data belongs needs to send the service data, the service application is carried in the second control data transmitted by the source node, and the service application may include a node identifier of the source node to which the second control data belongs, such as a source node number s, a node number di of a destination node participating in the service, and a channel identifier c of a multi-relay cooperative forwarding service channel used by the service, certainly including gradient information from the source node to the destination node di, where in the gradient information, when the communication mode is unicast, the destination node is single, and the corresponding gradient information only includes one gradient, when the communication mode is multicast, the destination node is multiple, and the corresponding gradient information includes multiple gradients, so that, in the gradient information, the source node reaching the destination node forms an equal gradient line with the node having the same gradient as the destination node, as shown in fig. 2, equal gradient line 2 between the destination node d1 and the source node s.

Based on this, the current node may obtain the first gradient and the second gradient in its own gradient table, and obtain the third gradient in the service application of the second control data, and thus, the current node may transmit the service data corresponding to the service application to the next-hop node when the sum of the first gradient and the second gradient is less than or equal to the third gradient.

It can be known from the foregoing solutions that, in a network data transmission method based on multi-relay cooperation provided in an embodiment of the present application, a gradient table is established on each node in a communication network, where the gradient table includes a hop count from each node to any other node, and when a node needs to transmit service data, whether the node forwards the service data is determined by determining between the hop counts, for example, a node only needs to forward the service data when a sum of gradients respectively reaching a source node and a destination node is less than or equal to a gradient between the source node and the destination node, so that in a process of forwarding the service data, system overhead caused by establishing a route between nodes is avoided, and thus data transmission efficiency in the network is improved.

In an implementation manner, when the current node establishes the gradient table of the current node according to the second control data, the following manner may be specifically implemented:

firstly, obtaining a source node identifier and a current transmission hop count in second control data, wherein the current transmission hop count is the number of nodes which are experienced by the second control data transmitted from a node corresponding to the source node identifier to the current node, and the current transmission hop count is greater than or equal to 1;

and then, recording the gradient between the node corresponding to the source node identification and the current node in a gradient table of the current node as the current transmission hop count.

After that, if the current node is not the destination node of the node corresponding to the source node identifier, after the gradient is recorded, the current node may further add 1 to the current transmission hop count in the second control data, and then transmit the second control data to the next hop node of the current node in the communication network by using the multi-relay cooperative forwarding control channel, so that the next hop node of the current node establishes a gradient table according to the received second control data, and the next hop node of the current node may establish its own gradient table by using the same scheme of establishing the gradient table by using the current node, which may specifically refer to the foregoing specific implementation scheme.

In a specific implementation, when the current node transmits a service application corresponding to the next-hop node, the method may specifically be implemented in the following manner:

first, the current node configures a time-frequency transmission parameter of a multi-relay cooperative forwarding service channel corresponding to a channel identifier in a service application of the current node, and specifically, the current node may configure a corresponding multi-relay cooperative forwarding service channel according to a channel identifier included in the service application in the second control data, for example, configure a time slot transmission parameter and a frequency domain transmission parameter of the service channel. In the time-frequency transmission parameters configured by the current node, a first time slot of the current node when the current node receives the service data by using the multi-relay cooperative forwarding service channel is different from a second time slot of the current node when the current node transmits the service data by using the multi-relay cooperative forwarding service channel, that is, a service channel time slot of a node in the communication network when receiving the service data is different from a service channel time slot of the node in the communication network when forwarding the service data.

And then, the current node transmits service data corresponding to the service application to the next hop node of the current node by using the configured multi-relay cooperative forwarding service channel.

Based on this, after the service corresponding to the service data is completed, that is, after the service data transmission is completed, the node in the communication network further needs to release the corresponding multi-relay cooperative forwarding service channel, specifically, taking the current node as an example, after the current node transmits the service data corresponding to the service application to the next hop node, the current node first obtains a service resource release request, where the service resource release request is a request generated by the source node of the service application, that is, after the source node of the service application completes the service data transmission, a service resource release request is generated and transmitted in the configured multi-relay cooperative forwarding service channel, and immediately releases the multi-relay cooperative forwarding service channel configured by the source node, and other nodes participating in the service data transmission, for example, after the current node completes the service data forwarding through its own multi-relay cooperative forwarding service channel and receives the service resource release request, and responding to the service resource release request to release the multi-relay cooperative forwarding service channel corresponding to the channel identifier of the current node.

In addition, before the current node responds to the service resource release request and releases the self-configured service multi-relay cooperative forwarding service channel, it is also necessary to forward the service resource release request to the next-hop node by using the self-configured service multi-relay cooperative forwarding service channel, and then release the self-configured service multi-relay cooperative forwarding service channel.

In one implementation, if the service data corresponding to the service application is a broadcast service type, the multi-relay cooperative forwarding control channel of the current node may be used to broadcast to other nodes in the communication network when the data volume of the service data corresponding to the service application in the second control data of the current node is less than or equal to a preset threshold, and specifically, the second control data may be used to carry the service data and broadcast to other nodes in the communication network through the multi-relay cooperative forwarding control channel;

and under the condition that the data volume of the service data corresponding to the service application in the second control data is larger than a preset threshold value, the current node reconfigures the time-frequency transmission parameters of a multi-relay cooperative forwarding service channel corresponding to the channel identifier in the service application of the current node, and further reuses the configured multi-relay cooperative forwarding service channel to transmit the service data corresponding to the service application to a next hop node of the current node.

In one implementation, when the current node transmits the first control data to each other node in the communication network by using its own multi-relay cooperative forwarding control channel, the current node may first obtain a channel usage right of the multi-relay cooperative forwarding control channel of the current node, for example, obtain the channel usage right of the multi-relay cooperative forwarding control channel based on a polling and token ring multi-relay cooperative forwarding channel access mechanism, and then transmit the first control data to each other node in the communication network by using the channel usage right of the multi-relay cooperative forwarding control channel.

Taking fig. 2 as an example, it shows a schematic diagram of multicast transmission performed by a node s, where destination nodes participating in multicast are nodes d1, d2, and d3, and the information of equal gradient lines established by a source node s to reach the destination node is 2, and 1, respectively. The isocratic line situation of the destination node d1 is shown in fig. 2, where the arrow of tnpmhl indicates that the node sends the mth token in the nth slot, and the token is in the ith hop transmission; the corresponding tnpmhl curve represents the range that the mth token sent in the nth slot can cover after l hops. The dashed lines with arrows in fig. 2 give the nodes and transmission paths participating in the multicast transmission from the source node s to the destination nodes d1, d2 and d 3. The method comprises the following specific steps:

1) the source node s extracts gradient information reaching each destination node by receiving the control packet sent by the destination node to establish a gradient table, and determines that equal gradient line information reaching the destination nodes d1, d2 and d3 are 2, 2 and 1, respectively.

2) After the source node s obtains the right to use the control channel, the gradient information is written into the service application of the control packet, and the control packet also contains information such as the used service channel, and then the control packet is broadcasted.

3) After receiving the service application, the one-hop neighbor of the source node s extracts the relevant information and judges whether the source node s needs to participate in the data forwarding. For example, after receiving the service application, the node 3 finds that the gradient from the node to the destination node d1 is 1 and the gradient from the node to the source node s is 1, and the gradient from the node to the node d1 carried by the service application is 2, which is exactly equal to the sum of the gradients from the node to the node s and the gradient from the node to the destination node d1, so that the node needs to participate in the forwarding of the multicast data. Similarly, node 4 finds itself needed to participate in data forwarding for destination nodes d1 and d2, and node 5 finds itself needed to participate in data forwarding for destination node d 2.

4) The

final nodes

3, 4, 5 determine that they need to participate in the forwarding of the multicast data.

It can be seen that in the communication network of this embodiment, the source node sending the data packet does not need to know the information of the next hop node, i.e. does not need routing information, but only needs to give its gradient to the destination node. Furthermore, the direction of data transmission in the communication network is determined in a distributed manner through the behavior of the network nodes, so that the data packets flow to the node with the lowest gradient (destination node). Meanwhile, in the process of one-time data transmission, a plurality of relay nodes may exist on the same gradient, so that diversity gain can be obtained through multi-relay forwarding, and the reliability of data transmission is improved. Further, when the nodes in the communication network move rapidly or the topology changes rapidly, as long as an available relay node exists on the same gradient, the successful transmission of data can be ensured.

In summary, in the present embodiment, based on the core idea of the resource scheduling algorithm of multi-relay cooperation, the multi-relay cooperation forwarding control channel is used to schedule a subsequent multi-relay cooperation forwarding service channel to support data packet transmission; meanwhile, the nodes participating in data transmission are determined in a distributed mode through a gradient-based algorithm, a data transmission link is further established, and multi-hop data transmission is completed. Therefore, in the embodiment, the fast overall network broadcast characteristic of multi-relay cooperative forwarding is fully utilized, fast, low-overhead and efficient overall network resource scheduling is performed, transmission of broadcast, multicast and unicast services of a network is supported, and fast interconnection and intercommunication between any nodes in the network are realized.

Referring to fig. 3, a schematic structural diagram of a network data transmission apparatus based on multi-relay cooperation according to a second embodiment of the present disclosure is shown, where the apparatus in this embodiment is applicable to any node in a communication network, and each node in the communication network has one multi-relay cooperation forwarding control channel and multiple multi-relay cooperation forwarding traffic channels. The apparatus in this embodiment is mainly used to reduce system overhead caused when data is transmitted between nodes in a communication network, so as to improve data transmission efficiency.

Specifically, the apparatus in this embodiment may include the following units:

a sending unit 301, configured to transmit first control data to each other node in the communication network by using a multi-relay cooperative forwarding control channel of the current node, so that each other node establishes a gradient table of the other node according to the received first control data, respectively, where a gradient between the other node and the current node in the gradient table of the other node is recorded as a current transmission hop count in the first control data;

a receiving unit 302, configured to receive second control data transmitted by each of the other nodes using a multi-relay cooperative forwarding control channel of the other node;

a creating unit 303, configured to create a gradient table of the current node according to the second control data, where a gradient between the current node and the other node in the gradient table of the current node is recorded as a current transmission hop count in the second control data;

a processing unit 304, configured to determine whether to forward the service data corresponding to the received service request according to the gradient table of the current node when the received second control data includes a service application;

wherein the sending unit 301 is further configured to: transmitting service data corresponding to the service application to a next hop node of the current node under the condition that the sum of the first gradient and the second gradient is less than or equal to a third gradient in the service application;

It can be known from the foregoing solutions that, in a network data transmission device based on multi-relay cooperation provided in the second embodiment of the present application, a gradient table is established on each node in a communication network, where the gradient table includes a hop count from each node to any other node, and when a node needs to transmit service data, whether the node forwards the service data is determined by determining between the hop counts, for example, a node only needs to forward the service data when a sum of gradients respectively reaching a source node and a destination node is less than or equal to a gradient between the source node and the destination node, so that in a process of forwarding the service data, system overhead caused by establishing a route between nodes is avoided, and thus data transmission efficiency in the network is improved.

In an implementation manner, the establishing unit 303, when establishing the gradient table of the current node according to the second control data, is specifically configured to:

obtaining a source node identifier and a current transmission hop count in the second control data, where the current transmission hop count is a number of nodes that the second control data is transmitted from a node corresponding to the source node identifier to the current node, and the current transmission hop count is greater than or equal to 1; and recording the gradient between the node corresponding to the source node identification and the current node in the gradient table of the current node as the current transmission hop count.

Optionally, if the current node is not the destination node of the node corresponding to the source node identifier, the establishing unit 303 is further configured to: adding 1 to the current transmission hop count in the second control data; and transmitting the second control data to a next hop node of the current node in the communication network by using a current multi-relay cooperative forwarding control channel, so that the next hop node establishes a gradient table according to the received second control data.

In an implementation manner, when the sending unit 301 transmits the service data corresponding to the service application to the next hop node, the sending unit is specifically configured to:

configuring time-frequency transmission parameters of a multi-relay cooperative forwarding service channel corresponding to a channel identifier in the service application of the current node; and transmitting the service data corresponding to the service application to the next hop node of the current node by using the configured multi-relay cooperative forwarding service channel.

Optionally, a first time slot of the current node when receiving the service data by using the multi-relay cooperative forwarding service channel is different from a second time slot of the current node when transmitting the service data by using the multi-relay cooperative forwarding service channel.

In an implementation manner, after the current node transmits service data corresponding to the service application to a next-hop node, the processing unit 304 is further configured to: obtaining a service resource release request; the service resource release request is a request generated by a source node of the service application; and responding to the service resource release request to release a multi-relay cooperative forwarding service channel corresponding to the channel identifier of the current node.

In an implementation manner, if the service data corresponding to the service application is a service type of broadcast, the sending unit 301 is further configured to:

under the condition that the data volume of the service data corresponding to the service application in the second control data is smaller than or equal to a preset threshold value, broadcasting to other nodes in the communication network by using a multi-relay cooperative forwarding control channel of the current node; when the data amount of the service data corresponding to the service application in the second control data is greater than the preset threshold, the processing unit 304 configures the time-frequency transmission parameter of the multi-relay cooperative forwarding service channel corresponding to the channel identifier in the service application of the current node.

In one implementation, when transmitting the first control data to each other node in the communication network by using the multi-relay cooperative forwarding control channel of the current node, the transmitting unit 301 is specifically configured to: obtaining a channel use right of a multi-relay cooperative forwarding control channel of the current node; transmitting first control data to each other node in the communication network using the channel usage rights of the multi-relay cooperative forwarding control channel.

It should be noted that, for the specific implementation of each unit in the present embodiment, reference may be made to the corresponding content in the foregoing, and details are not described here.

Referring to fig. 4, a schematic structural diagram of an electronic device according to a third embodiment of the present invention is provided, where the electronic device may be used as any node in a communication network, and each node in the communication network has one multi-relay cooperative forwarding control channel and multiple multi-relay cooperative forwarding traffic channels. The technical scheme in the embodiment is mainly used for reducing the system overhead caused by data transmission between nodes in the communication network so as to improve the efficiency of data transmission.

Specifically, the electronic device in this embodiment may include the following structure:

a transmission interface 401, which may be implemented by a component capable of data transmission, such as an antenna, and configured to transmit first control data to each other node in the communication network by using a multi-relay cooperative forwarding control channel of the current node, so that each other node establishes a gradient table of the other node according to the received first control data, where a gradient between the other node and the current node in the gradient table of the other node is recorded as a current transmission hop count in the first control data;

the transmission interface 401 is further configured to receive second control data transmitted by each of the other nodes using the multi-relay cooperative forwarding control channel of the other node;

a processor 402, configured to establish a gradient table of the current node according to the second control data, where a gradient between the current node and the other node in the gradient table of the current node is recorded as a current transmission hop count in the second control data;

the processor 402 is further configured to: determining whether to forward the service data corresponding to the received service request according to the gradient table of the current node under the condition that the received second control data contains the service application,

when the sum of the first gradient and the second gradient is less than or equal to a third gradient in the service application, the transmission interface 401 is utilized to transmit service data corresponding to the service application to a next hop node of the current node;

It can be known from the foregoing solutions that, in an electronic device provided in the third embodiment of the present application, a gradient table is established on each node in a communication network, where the gradient table includes a hop count from each node to any other node, and when a node needs to transmit service data, whether the node forwards the service data is determined by determining between the hop counts, for example, a node only needs to forward the service data when a sum of gradients respectively reaching a source node and a destination node is less than or equal to a gradient between the source node and the destination node, so that in a process of implementing service data forwarding, system overhead caused by establishing a route between nodes can be avoided, and thus data transmission efficiency in the network is improved.

It should be noted that, in the present embodiment, the specific implementation of the processor 402 can refer to the corresponding content in the foregoing, and is not described in detail here.

The technical scheme of the application can be applied to various types of communication networks, such as a mobile ad hoc network, a layered networking and the like, and the communication network can be a network based on the cooperative diversity technology in the foregoing, and can also be a general mobile ad hoc network, that is, a network not applicable to the cooperative diversity technology. The following describes a technical scheme of the present application, taking a cooperative diversity type multi-relay cooperative forwarding network as an example:

the technical scheme in the application mainly relates to cooperative diversity type multi-relay cooperative forwarding, and the retransmission utilizes a cooperative diversity technology to realize rapid data broadcasting. The concept of multi-relay cooperative forwarding is illustrated below by a simple example, where a multi-relay cooperative forwarding network needs to have many network functions, which will be described in detail after the example. The example has two key assumptions, Time Division Multiple Access (TDMA), and autonomous cooperative communication. All nodes use a common TDMA frame format and can realize time slot level coarse synchronization, the coarse synchronization can be realized by a pilot signal with low overhead, and the coarse synchronization can be realized by the assistance of a GPS under the condition. Autonomous cooperative communication is used to ensure that nodes providing concurrent transmission for the same packet within the transmission coverage do not collide, and cooperative diversity can be achieved. This autonomous cooperation requires no additional coordination other than TDMA-level synchronization.

The broadcast mechanism in the communication network is shown in fig. 5, which is a multi-relay cooperative forwarding network broadcast protocol of one 3-slot (M ═ 3) TDMA frame (frame1 or frame2), and fig. 5 contains a source node and a relay node, and the relay node indicates its distance (hop count) from the source node by number. In general, assume that M ≧ 3 in the TDMA frame of M slots, M ≧ 3 in the communication network system shown in fig. 5, and the corresponding slots are labeled A, B and C. Assume that the source node transmits a packet on time slot a of the first TDMA frame. By definition, all nodes that successfully receive this packet are 1 hop away from the source node. The node that is 1 hop away from the source node then forwards the same information on time slot B and is received by the node that is 2 hops away from the source node. Nodes that hop 2 away from the source node then forward the same information on time slot C. The relay node, which is 3 hops away from the source node, continues relaying on time slot a of the 2 nd TDMA frame. In this manner, packets are propagated out from the source node by way of decoding and forwarding. To prevent back propagation towards the information source, each node relays a given packet only once. For example, a node that is 1 hop away from the source node may receive the same broadcast packet on slot a and slot C, but only on slot B.

As shown in fig. 5, multiple 2-hop nodes may receive the same packet forwarded from multiple 1-hop nodes on the same time slot. According to the autonomous cooperative communication scheme, the packets neither collide nor cause destructive interference. Thus, any number of relay signals may be cooperatively transmitted to one or more nodes without other coordination than TDMA slot coarse synchronization. Furthermore, any node may also participate in multiple such cooperative transmission groups without knowing information about its co-group cooperating nodes.

Through the spatial multiplexing of the time slots, the pipelined transmission of the packets can be realized, and the transmission time slots are provided for the source node every M time slots. For example, in fig. 5, a node that is 1 hop away from the source node will not receive a packet transmitted by a node that is 2 hops away from the source node in time slot a of the 2 nd TDMA frame. Thus, the source node can safely and reliably transmit the 2 nd packet during the time slot. It is readily demonstrated that M must be at least 3 to enable such spatially-pipelined operation. Choosing a larger number of M may trade off throughput for robustness to topology changes.

Based on the above communication network, routing protocols (RIP, OSPF) can be designed for wired fixed networks, their topology is fixed, and no major network structure changes occur. The wireless mobile network structure is dynamically changed, so that the conventional routing protocol can take a great deal of cost to reroute when the topological structure is changed, and the protocol state is always in an unconverged state. Therefore, a special routing protocol applied to the wireless mobile network is needed, and according to the structure and characteristics of the wireless mobile network, the designed routing protocol must satisfy the following conditions:

(1) the capability of quick strain to the dynamic change of the network topological structure is realized;

(2) avoiding the occurrence of routing loop as much as possible;

(3) a convenient and simple network node positioning method is provided;

(4) limited bandwidth resources are efficiently utilized, and unnecessary overhead is compressed as much as possible;

(5) the safety measure is provided, the possibility of attack is reduced, and certain survivability is achieved;

(6) a single channel is supported.

The routing protocol of the mobile ad hoc network can be divided into a unicast route and a multicast route according to a forwarding mode. Among them, unicast routing is the most dominant type of routing protocol for ad hoc networks. According to the route triggering principle, the unicast route can be divided into 3 types of a prior-check type route protocol, a reactive type route protocol and a mixed type route protocol. Through long-term deep research on various routing protocols of the mobile ad hoc network, a plurality of new or improved protocols suitable for different networks, different scenes and different conditions are provided. However, different routing protocols are inherently adaptable to different application scenarios, and none of them is universally applicable:

1. the method has the advantages that the routing time delay of the first-test type routing is short, the topology maintenance is timely, and the method is suitable for scenes with small topology structure change;

2. the reactive routing acquires routing information as required, is more suitable for scenes with severe topology change, and only a few nodes need to communicate with each other;

3. the hybrid routing protocol uses the proactive routing protocol in a small-range local area, and the on-demand routing protocol is adopted for routing search of nodes outside the local area, so that the advantages of the on-demand routing protocol and the proactive routing protocol are complemented, the bandwidth consumption and the routing discovery delay are relatively low, and the hybrid routing protocol can perform well in various scenes.

Therefore, in the multi-hop unicast and multicast transmission process of the mobile ad hoc network, the nodes participating in transmission are determined through the routing information, and corresponding resources are scheduled. The establishment and maintenance of the route may generate non-negligible system overhead, and especially for a network with fast and frequent network topology change, the overhead must be added to improve the performance. In the multi-hop unicast and multicast transmission process of the mobile ad hoc network, no matter a table-driven routing or an on-demand routing strategy is adopted, the source node and the relay node need to clearly indicate the next-hop node information according to the routing information in the data sending process, and if the information is unreliable (the next-hop node is not reachable due to topology change caused by node movement, wireless channel deterioration and the like), data packet transmission failure is caused, and packet loss or unnecessary time delay is generated.

The technical solution of the present application is specifically described below:

in the application, resource scheduling based on multi-relay cooperative forwarding is suitable for a network with the following characteristics:

the nodes in the mobile ad hoc network are assumed to have the capability of multi-relay cooperative forwarding, and the cooperative diversity technology can be utilized to realize rapid data broadcasting. For convenience of description, the following refers to a network having one multi-relay cooperative forwarding control channel and multiple multi-relay cooperative forwarding traffic channels, and is dedicated to fast network-wide forwarding of control packets and traffic packets, as shown in fig. 6 by the control channel, the traffic channel, the time slot and the frequency (f1-f4), and the nodes in the communication network of the present application have the following characteristics:

1. assuming that a multi-relay cooperative forwarding channel consists of N pre-specified time slots in a frame structure, nodes using the channel can be divided into a source node, a relay forwarding node and a destination node according to the difference of node identities using the multi-relay cooperative forwarding channel. The data packet is sent by a source node, other nodes detect each time slot of the multi-relay cooperative forwarding channel in real time, and after a certain data packet received by the relay forwarding node for the first time, the packet is forwarded at the next time slot of the channel.

2. It is assumed that the nodes can transmit their own control packets sequentially according to a certain rule or randomly by using a multi-relay cooperative forwarding control channel, and the packets can be received by all nodes in the network without collision. For example, by using a polling and token mechanism, nodes in the network periodically obtain the use right of tokens through a distributed polling process, and send own control packets according to requirements, and each token and corresponding packets are forwarded to the whole network through multiple relays of other nodes.

3. Assuming that a node in the network carries "identity information of the node and hop count of packet transmission through a special packet or token, the node acquires a gradient of a packet sending node (source node)" by participating in multi-relay cooperative forwarding of the packet, where the gradient is defined as the hop count from the node to the packet sending node (source node).

4. The nodes reaching the same node and having the same gradient form an equal gradient line, the nodes on the equal gradient line transmit unicast or multicast data in a multi-relay cooperation mode, the data are delivered to the nodes on the equal gradient line with the gradient smaller than the gradient of the nodes, and then the data are delivered to a target node.

It should be noted that, according to different communication modes, data communication in the mobile ad hoc network can be classified into three categories, namely broadcast, multicast and unicast. Due to the characteristics of no center, no distribution, no topology dynamic change and no multi-hop transmission of the mobile ad hoc network, one key problem for completing the three types of data transmission is how to schedule nodes participating in communication to the same available service resource block (multi-relay cooperative forwarding channel), and how to complete the multi-hop data transmission with low overhead, high efficiency and no conflict, namely how to perform distributed resource coordination, scheduling and distribution of the mobile ad hoc network.

Specifically, the algorithm in the technical scheme of the application is designed as follows:

the core idea of the resource scheduling algorithm based on multi-relay cooperation is that a multi-relay cooperation forwarding control channel is used for scheduling a subsequent multi-relay cooperation forwarding service channel to support packet transmission; meanwhile, a data transmission link is established by determining nodes participating in data transmission in a distributed manner based on a gradient algorithm, so that multi-hop data transmission is completed. The algorithm makes full use of the rapid whole-network broadcasting characteristic of multi-relay cooperative forwarding, performs rapid, low-overhead and efficient whole-network resource scheduling, supports the transmission of network broadcasting, multicasting and unicasting services, and realizes rapid interconnection and intercommunication among any nodes in the network.

As shown in fig. 7, a flowchart of a transmission resource scheduling algorithm based on multi-relay cooperation implemented by the technical solution of the present application is given, and the algorithm may be divided into the following stages:

(1) gradient establishing phase

After the network is initialized, nodes in the network use a multi-relay cooperative forwarding control channel to send control packets through a certain rule (such as a multi-relay cooperative forwarding channel access mechanism based on polling and token ring), and the control packets can reach the whole network through multi-relay forwarding of other nodes.

The control packet includes identity information of a sending node and a HOP count field (HOP field) of the control packet, and the HOP field is initially set to 1. After receiving the control packet sent by the sending node or other relay forwarding nodes, the relay forwarding node extracts the hop count information, records and maintains a gradient list reaching the corresponding sending node. After the relay forwarding process finishes the received control packet, the HOP count information of the HOP field of the control packet is added by one, and then the packet is forwarded on the subsequent multi-relay cooperative channel.

When all nodes in the network use the multi-relay forwarding cooperative control channel to complete the control of the packet whole network broadcasting, any node in the network establishes and maintains a gradient list from the node to other nodes.

(2) Resource allocation phase

After a node s in the network has a service requirement, firstly, a gradient list maintained by the node s is inquired, the gradient g (s, di) of a di (i is more than or equal to 1) reaching a target node is obtained, namely, an equal gradient line of the target node where the node is located is obtained, then, the use right of a multi-relay cooperative forwarding control channel is obtained through a certain rule (such as a polling and token ring-based mode), and a service application is broadcasted on the multi-relay cooperative forwarding control channel.

The service application carries a source node number s, a destination node number di participating in the service, a multi-relay cooperative forwarding service channel c used by the service, and isocratic line information g (s, di) from the service application to the destination node di (unicast is a single destination node i being 1, multicast is a plurality of destination nodes i being >1, and broadcast is appointed to be uniform isocratic line information), and the multi-relay cooperative forwarding service channel c of the service application is configured to transmit service data.

Then, after receiving the service application of the multi-relay cooperative forwarding control channel, other nodes r in the network extract corresponding information, forward the service application according to the multi-relay cooperative forwarding rule, and then compare whether the sum of the equal gradient lines g (r, di) from the node r to each service destination node and the equal gradient lines g (r, s) from the node r to the source node s is less than or equal to the equal gradient lines g (s, di) from the service application packet to the corresponding service destination node di.

As mentioned above, if g (r, di) + g (r, s) ≦ g (s, di) exists for any destination node i, then configure its own multi-relay cooperative forwarding service channel c, and participate in service data forwarding on this channel; otherwise, the corresponding multi-relay cooperative forwarding service channel c does not need to be configured, that is, the multi-relay cooperative forwarding service channel c does not participate in service data forwarding.

In addition, if the service request is a broadcast service, all nodes in the network need to participate in service application transmission, and then configure the multi-relay cooperative forwarding service channel c according to the parameters carried by the control channel to participate in the subsequent broadcast service.

(3) Service delivery phase

And when the service source node sends a service application on the multi-relay cooperative forwarding control channel, configuring a multi-relay cooperative forwarding service channel c thereof immediately, and sending service data. And other nodes r needing to participate in service forwarding in the network participate in service data forwarding in the configured multi-relay cooperative forwarding service channel c.

(4) Resource release phase

And after the service source node finishes service grouping transmission, a service resource release request is transmitted in the configured multi-relay cooperative forwarding service channel c, and the configured multi-relay cooperative forwarding service channel is released immediately.

After receiving the corresponding service resource release request, the other nodes participating in service transmission immediately release the configured multi-relay cooperative forwarding service channel after the service channel forwards the resource release request.

Through the resource scheduling algorithm based on multi-relay cooperative forwarding, nodes in the communication network can dynamically and flexibly schedule and use a multi-relay cooperative forwarding service channel to complete unicast, multicast and broadcast services of the network. In addition, the system can establish a plurality of traffic channels by using a plurality of multi-relay cooperative forwarding traffic channels, and simultaneously support multiple unicast, multicast and broadcast services.

For the whole network broadcasting, the data packet to be sent can be divided into two broadcasting modes of multi-relay cooperative forwarding control channel carrying and multi-relay cooperative forwarding service channel scheduling according to the size of the data packet:

1. the multi-relay cooperative forwarding control channel is simple in carrying mode, when a node has a broadcast packet to send, the node obtains the use right of the control channel according to a certain rule sequence (for example, an internetwork cooperation mechanism based on polling and a token ring is used), and then the control channel is used for quickly broadcasting partial burst packets to the whole network.

2. The core idea of the transmission is to use the multi-relay cooperative forwarding control channel to coordinate, schedule and allocate resources, quickly schedule all nodes in the network to the same multi-relay cooperative forwarding service channel, and then complete the broadcasting of the data packets through the channel.

For unicast and multicast, a sending node applies for resource scheduling by carrying unicast or multicast requirements on a multi-relay cooperative forwarding control channel, and a forwarding node judges whether the forwarding node needs to participate in unicast or multicast service or not by using a gradient-based algorithm, and then rapidly configures a multicast channel on a multi-relay cooperative forwarding service channel of the same frame, for example, as described in the related content of fig. 2.

Further, based on the implementation, the method and the device can be used for resource scheduling and data transmission among networking nodes, and the network nodes send and receive data in a multi-relay cooperative forwarding mode; the method can also be used for inter-network resource scheduling and data transmission between control nodes in a layered networking system, and resource scheduling and data transmission between common nodes and the control nodes.

An application background of an example description algorithm of hierarchical networking and an example of multi-relay cooperative forwarding are given below to describe a mode for realizing packet transmission by using a cooperative diversity technology, a token design and an inter-network cooperation mechanism, so as to describe that a gradient establishment mechanism of the algorithm can be combined with other networking mechanisms to realize high speed and low overhead.

More generally, the algorithm presented in the present application can be applied to a general mobile ad hoc network, i.e. a network that does not use cooperative diversity techniques. The difference is that the nodes in the network broadcast control packets in a non-multi-relay cooperative forwarding mode, establish a gradient list, schedule resources based on a gradient algorithm in a non-relay forwarding mode, and send service packets.

1. Packet networking example

It is assumed that a low-rate (user physical layer rate 20kbps) narrowband (25kHz) system adopts a layered networking mode, uses a plurality of frequency points (channels) to form an integral and connected network, and simultaneously divides the whole network into a plurality of subnets (groups/clusters) which can communicate with each other. Each sub-network (group/cluster) is composed of a control node (group head/cluster head) and a plurality of common nodes, the control node is generated by the dynamic election of the nodes in the network according to a certain strategy and is responsible for the resource coordination and communication among networks and the resource management and scheduling in the networks; the common nodes only belong to one sub-network at the same time, receive the management and scheduling of the control nodes in the network, participate in data transmission between networks or in the network, and participate in the election and maintenance of the control nodes in the network. As shown in fig. 8, an example of narrowband networking is given, the whole network is composed of four sub-networks, each sub-network is composed of 1 control node (sub-i) and 15 ordinary nodes, communication in the sub-networks adopts a communication mode of a distributed system, and inter-network communication is coordinated and managed by the control nodes.

The frame structure of the narrowband system is shown in fig. 9, and the resource available to the node system is divided into a plurality of resource blocks in the time dimension and the frequency dimension, where the time length of each resource block is 10ms, and the frequency domain width is 25 kHz. The resource block is the minimum unit of schedulable resources of the system, and all nodes in the network can only use one resource block to receive or send data at the same time. As shown in fig. 9, the time slots in one frame are divided into a plurality of virtual channels, such as a synchronization channel, a multi-relay cooperative channel, a timely multi-relay cooperative channel, and a subnet/timely subnet traffic channel, according to the function. Wherein:

the synchronous channel is used for carrying out whole network synchronization and is only periodically distributed on a frequency point f0, and all nodes in the whole network need to carry out synchronous data transmission or interception on the channel;

the multi-relay cooperative channel is used for coordinating and scheduling resources among networks and sending and receiving partial whole network broadcast data, is periodically distributed on a frequency point f0, and a whole network node needs to participate in sending and receiving whole network data in the channel;

the timely multi-relay cooperative channel is used for voice broadcast or data broadcast of the whole network or among networks, is periodically distributed on all frequency points, allows partial sub-networks or all sub-networks in the network to use the timely multi-relay cooperative channel on a certain frequency point through inter-network resource coordination and scheduling, and completes transmission of voice and data of the whole network or among networks;

the subnet/timely subnet service channel is used for transmitting service in the subnet, and the subnet service channel of each subnet is periodically distributed on an independent frequency point to receive the management and scheduling of the control node.

It can be seen that each subnet uses different frequency points for networking, and the frequency points are separated from each other by frequency domains, but the subnets simultaneously use a common synchronization channel, a multi-relay cooperation channel, and a timely multi-relay cooperation channel to perform network synchronization and synchronization maintenance, inter-network resource coordination and scheduling, and inter-network voice and data communication. In addition, when the timely multi-relay cooperative channel is not used, the timely multi-relay cooperative channel can be used as a subnet service channel in the subnet, namely, the part of resource blocks are multiplexed into the timely multi-relay cooperative channel and the timely subnet service channel in terms of time, and the resource blocks are used as common service time slots of each subnet in other use modes, so that unicast and broadcast services are supported.

2. Multi-relay cooperative forwarding instance foundation implementation

An alternative multi-relay cooperative communication method is Barrage RelayNetwork (BRN). BRN is based on two key assumptions, one being TDMA and the other being autonomous cooperative communication. All nodes use a common TDMA framing format and require that slot level coarse synchronization be achieved. Autonomous cooperation is used for ensuring that nodes which provide concurrent transmission for the same group in a transmission coverage range not only do not conflict, but also can realize cooperative diversity; this autonomous cooperation requires no additional coordination other than TDMA-level synchronization. The basis for the implementation of autonomous cooperative communication is phase jitter and advanced turbo-like error correction codes. Each transmitting node adds pseudo-random jitter to the initial phase of the carrier wave, introduces time-varying channel characteristics to the superposed signal received by the receiving node, and advanced error correcting codes can acquire time diversity gain from the equivalent time-varying fading channel. Dithering may prevent the combined signal received by the receiver from exhibiting cancellation in some cases. Specifically, each code block may be divided into a plurality of bursts, and a scheme of adding phase jitter burst by burst is employed. In the case where the same training sequence is used by each transmitting node, the receiver may estimate the composite channel parameters on each burst based on the known sequence. Thus, the receiver can process the received signal in the same manner as for uncooperative transmission without knowing the number of participating transmitting nodes. Each transmitter does not need to know its channel state information in advance, nor even whether other transmitters are participating in the cooperation.

As described above, the BRN preprocesses the signal at the transmitting end, so that the same information sent by multiple relays at the same time is superimposed at the receiving end to obtain a diversity gain, but this way of cooperatively forwarding multiple relays requires that the data packets sent by all relay nodes at the same time are the same.

3. Example of token design

Polling (Polling) originally originated from the way that the CPU decided how to provide peripheral services, also called "Programming I/O", and was later developed as a processing procedure for the base station to allocate bandwidth to the terminal. In token ring networks there is a special frame called a "token", which is continuously transmitted over the ring to determine when a node can send a data packet.

In order to support reverse unicast data transmission, combining the token with multi-relay cooperative communication, as shown in fig. 10, a token frame structure is given, and the specific field meanings are as follows:

sd (start limiter) and ed (end limiter) are delimiters of the control part of the token to facilitate detection of the token;

OwneriD represents the ID number of a node in the network, indicates the owner of the current token, and is configured by the last owner of the token;

the HOP represents the HOP number of the packet forwarding node from the source node, and is used for identifying the distance between the node participating in the multi-relay cooperative forwarding and a central node (source node), and the source node sets the value to 0;

DATA represents DATA carried by a token, which can be a control instruction or service DATA, and one token can carry a plurality of DATA packets;

other fields are indicated by other, and may be extended as desired, such as adding sequence number fields to prevent loops.

In the multi-relay cooperation process, the information of SD, Owner ID and DATA fields in the token forwarded by the multiple relay nodes at the same time is completely the same, so that diversity gain is obtained conveniently; and the HOP field is different according to different positions where the relay forwarding node participates in forwarding, and after the relay forwarding node receives the data packet, the value of the HOP field is added with one to forward the data packet.

4. Internetwork cooperation example based on polling and token ring

The whole network is assumed to be divided into a plurality of sub-networks (groups/clusters), each sub-network elects a control node (group head/cluster head), and a virtual center sub-network and a virtual center node (control node of the virtual center sub-network) of the whole network are determined in a designated or distributed negotiation manner. After the network initialization is finished, each subnet uses one frequency point or one group of frequency points to carry out networking and is responsible for data transmission in the network; meanwhile, each sub-network uses a multi-relay cooperative channel to carry out data transmission and resource scheduling between networks, and the time slot is used for completing the establishment of transmission path information between sub-network control nodes.

As shown in fig. 11, an example of the inter-network cooperative flow based on polling and token ring is given, in which a polling process is initiated by the control node SubN-0, a token is sent and the control node SubN-1 that gets the token next is designated. The arrow of tnpmhl in the figure indicates that the node sends the mth token at the nth time slot and the token is carrying out the ith hop transmission, for example, t4p1h4 indicates that the node sends the 1 st token at the 4 th time slot and the token is carrying out the 4 th hop transmission; the corresponding tnpmhl curve represents the range that the mth token sent in the nth slot can cover after l hops. It can be seen that the control node can send its token after obtaining the token and keeping a safe interval, so that if the network is large enough, multiple tokens may be transmitted successively at different locations in the network at the same time. In the example, after the network synchronization, the specific process of the inter-network cooperation mechanism is as follows:

the network virtual center node subN-0 determines the next control node subN-1 using the inter-network cooperation time slot according to a certain polling rule, and broadcasts the inter-network control information of the whole network and the information of the control node subN-1 using the inter-network cooperation time slot;

all other nodes in the network determine whether the nodes need to participate in data transmission according to the type of the internetwork cooperation information, and establish and maintain a gradient list to the data transmission node (source node) according to the received information. Through this gradient list, the node can send data to the originating node (source node) broadcasting the data;

after receiving the broadcast information sent by the network control node subN-0, the control node subN-1 establishes a gradient list to the network virtual center node subN-0, determines the next control node subN-2 using the inter-network cooperation time slot according to a certain polling rule, and sends the inter-network control information and the information of the control node subN-2 using the inter-network cooperation time slot;

after receiving the broadcast information sent by the control node subN-j, the control node subN-i establishes a gradient list to the control node subN-j, determines the next control node subN-0 using the inter-network cooperation time slot according to a certain polling rule, and sends the inter-network control information and the information of the control node subN-0 using the inter-network cooperation time slot.

The cooperation mechanism can dynamically adapt to the scale of each subnet, support the change and expansion of the subnet scale and fully utilize the inter-network cooperation time slot. Meanwhile, the cooperation mechanism works based on network synchronization and multi-relay cooperative communication, nodes in the network acquire specific positions of all virtual channels in the system through network synchronization, and the multi-relay cooperative communication is used for rapidly transmitting the whole network broadcast information without scheduling.

5. Scheduling example of multicast resources between networks

For the internetwork data broadcast (multi-subnet data multicast service) of the non-whole network, because the source subnet and the destination subnet may not be directly connected, as shown in fig. 12, the mobile ad hoc network is composed of four subnets, and the control nodes using the corresponding subnets are respectively denoted as sub n-0, sub n-1, sub n-2, and sub n-3, and a node s in the subnet sub n-0 has a data packet to be broadcast in the subnets sub n-0 and sub n-2, but the subnets sub n-0 and sub n-2 are not directly connected, and a connection between the two subnets needs to be established in the data multicast service scheduling process.

Therefore, the scheduling of the multi-relay cooperative forwarding service channel is much more complex, and is more suitable for the data multicast service with low time delay requirement among multiple subnets, and the detailed flow is as follows:

(1) when the nodes s have the internetwork multicast data packets to be sent, the data sending requests are sent to the control nodes subN-i of the sub-network in an internetwork unicast mode, and then the data multicast service information is updated according to the information received by the multi-relay cooperative channel.

(2) And when the control node subN-i receives the multi-subnet data multicast service requests of other nodes of the subnet or the multi-subnet data multicast service requests of the control node subN-i, the control node subN-i waits for the token frame in the multi-relay cooperative channel.

(3) After the control node subN-i obtains the token, writing a subnet list needing to be communicated, the hop count from the control node subN-i to the subnet control node needing to be communicated and a working timely multi-relay cooperative channel into a token frame, broadcasting the token and related information through the multi-relay cooperative channel, and then updating inter-network data transmission information according to the information received by the multi-relay cooperative channel.

(4) And the common nodes in the network participate in the forwarding of the token in the multi-relay cooperative channel, simultaneously extract the information carried by the token, update and maintain the data multicast service information, and judge whether the common nodes are the target sub-network of the data multicast service. If so, configuring the self timely multi-relay cooperative channel according to the working timely multi-relay cooperative channel information, and waiting and participating the internetwork data multicast service in the channel; if not, forwarding information such as a subnet list needing to be communicated, hop count from the source node to a subnet control node participating in multicast, working timely multi-relay cooperative channel and the like on the multi-relay cooperative channel, and judging whether the multi-relay cooperative channel needs to participate in unicast data transmission of the timely multi-relay cooperative channel according to the information and the hop count of the subnet control node participating in multicast.

(5) Based on the realization, if the nodes of the non-target sub-network need to participate in the multicast data transmission of the timely multi-relay cooperative channel, the self timely multi-relay cooperative channel is configured according to the working timely multi-relay cooperative channel, and the nodes wait for and participate in the internetwork data multicast service in the channel.

(6) When the node s finds that all the subnets related to the internetwork multicast data transmission are informed, after a safe interval is reserved, the internetwork data broadcast is initiated in a working timely multi-relay cooperative channel.

(7) The frequency point of the sub-network where the sub-network is located is used as the timely multi-relay channel of the sub-network, and the sub-network participates in receiving and sending the multicast service in the channel.

(8) And after the nodes s finish the internetwork multicast data, sending a multicast ending packet in a timely multi-relay channel.

(9) After all nodes participating in the multicast service receive a broadcast ending packet, the timely multi-relay channel is released, and the corresponding timely multi-relay channel becomes a timely subnet service channel.

In summary, the present application performs fast forwarding of control packets through multi-relay cooperative forwarding, and the receiving and forwarding nodes establish a gradient to the sending node. And when multi-hop unicast, multicast or broadcast services are sent, nodes participating in data forwarding are determined through the information of the equal gradient lines, a multi-relay cooperative forwarding service channel is scheduled, and the packet forwarding direction is indicated in a distributed mode. Meanwhile, the method and the system utilize the plurality of forwarding nodes on the equal-gradient line to forward the packets, so that the adaptability of the system to the network topology change is improved, and the reliability of unicast data transmission is improved.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), memory, Read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A network data transmission method based on multi-relay cooperation is characterized in that the method is suitable for any node in a communication network, the node is provided with a multi-relay cooperation forwarding control channel and a plurality of multi-relay cooperation forwarding service channels, and the method comprises the following steps:

2. The method of claim 1, wherein establishing a gradient table for the current node based on the second control data comprises:

3. The method of claim 2, wherein if the current node is not the destination node of the node corresponding to the source node identification, the method further comprises:

adding 1 to the current transmission hop count in the second control data;

4. The method of claim 1, wherein the transmitting, by the current node, service data corresponding to the service application to a next hop node comprises:

5. The method of claim 4, wherein a first time slot of the current node when receiving the traffic data using the multi-relay cooperative forwarding traffic channel is different from a second time slot of the current node when transmitting the traffic data using the multi-relay cooperative forwarding traffic channel.

6. The method of claim 4, wherein after the current node transmits service data corresponding to the service application to a next hop node, the method further comprises:

7. The method of claim 4, wherein if the service data corresponding to the service application is a service type of broadcast, the method further comprises:

8. The method of claim 1, wherein transmitting first control data to each other node in the communication network using a multi-relay cooperative forwarding control channel of the current node comprises:

9. A network data transmission device based on multi-relay cooperation, which is applied to any node in a communication network, wherein the node has one multi-relay cooperative forwarding control channel and a plurality of multi-relay cooperative forwarding traffic channels, and the device comprises:

10. An electronic device, wherein a node in a communication network has a multi-relay cooperative forwarding control channel and a plurality of multi-relay cooperative forwarding traffic channels, the electronic device comprising: