A low-latency alarm data transmission method suitable for star-type wireless ad hoc networks

Abstract

The application discloses a low-latency alarm data transmission method suitable for a star-type wireless ad hoc network, and comprises the following steps: firstly, a gateway and nodes form a star-type ad hoc network through time division multiple access, and the gateway allocates fixed communication time slots to each node; then, the gateway inserts dynamic time slots in the interval of the fixed time slots, and when a node generates alarm data, the node transmits the data to the gateway through the dynamic time slots; finally, the gateway adopts a multi-key data scheduling strategy to schedule the data, so as to ensure low-latency transmission of the alarm data. The application designs a full-link low-latency communication from two aspects of node access and gateway data forwarding, so as to ensure low-latency transmission of burst key service data under the condition of mixed transmission of multiple services.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of wireless communication, and particularly relates to a low-latency alarm data transmission method suitable for a star-type wireless ad hoc network. BACKGROUND

[0002] A wireless ad hoc network is a point-to-point communication network with equal nodes, and each node can communicate with one or more peer nodes. Compared with a traditional cellular network structure, the wireless ad hoc network has the characteristics of simple deployment, good non-line-of-sight transmission effect, strong robustness and flexible structure, and can form a chain-type, star-type and hybrid network topology according to the application scene. Through the relay transmission of different nodes, the wireless ad hoc network can realize multi-hop transmission, thereby realizing a longer distance coverage. The wireless ad hoc network is suitable for scenarios that do not need to be deployed in advance but need to open a dedicated network temporarily, such as power communication, emergency communication, fire rescue, forest fire, marine fleet communication, vehicle fleet communication, unpopulated area communication, underground communication and activity security, etc. However, with the promotion of digitalization and intelligentization construction of various industries, the requirements of various scenes on wireless communication are getting higher and higher, especially the low-latency transmission demand of alarm data under the condition of mixed transmission of multiple services is very urgent. Most of the existing technical means reduce the communication latency through the scheduling and allocation of resources, the method is not flexible enough and does not consider the low-latency communication problem of the whole link from the node to the gateway, and therefore cannot meet the current communication demand. SUMMARY

[0003] The application aims to solve the above problems in the prior art, and provides a low-latency alarm data transmission method suitable for a star-type wireless ad hoc network, which designs a whole-link low-latency communication method from two aspects of fast access of a communication node and low-latency forwarding of a communication gateway, and guarantees the low-latency transmission of alarm data under the condition of mixed transmission of multiple services.

[0004] The technical scheme adopted by the application to achieve the above object is as follows:

[0005] A low-latency alarm data transmission method suitable for a star-type wireless ad hoc network, comprising the following steps:

[0006] 1) A gateway and a node form a star-type ad hoc network, the gateway allocates a fixed communication time slot to each node for transmitting data without alarm; 2) The gateway inserts a dynamic time slot in the interval of the fixed time slot, and the node transmits alarm data to the gateway by competing for the dynamic time slot; 3) The gateway adopts a multi-key level data scheduling strategy to schedule the data, thereby guaranteeing the low-latency transmission of alarm data.

[0007] The node accesses the gateway in a time division multiple access mode, and the gateway divides fixed uplink and downlink time slots ΔT1 and ΔT2 for each node.

[0008] N uplink time slots are divided according to the number N of nodes, and are used for transmitting data from each node to the gateway; one downlink time slot is set every 1 uplink time slot, and is used for transmitting data from the gateway to the nodes.

[0009] The competitive dynamic time slot data transmission is inserting a dynamic time slot for burst alarm data within the required time delay range.

[0010] A dynamic time slot ΔT3 is inserted every M node fixed time slot, so as to meet the alarm data time delay condition:

[0011] M(ΔT1+ΔT2)+ΔT3≤Δt.

[0012] The multi-key level data scheduling is:

[0013] The gateway divides the received data into key level data and priority level data according to the level;

[0014] The gateway forwards the data according to the data type and different levels.

[0015] The burst alarm data is divided into key level data of different levels; and the ordinary service data is divided into priority level data of different levels.

[0016] The method for forwarding the data is:

[0017] The key level data is directly forwarded;

[0018] The priority level data is queued and forwarded.

[0019] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0020] The present application aims at the low time delay requirement of alarm data under the condition of mixed transmission of multiple services, and designs a whole link low time delay communication from two aspects of node access and gateway data forwarding. The dynamic time slot which can be preempted is designed on the basis of the fixed time slot. Meanwhile, the gateway designs different forwarding priority levels according to different alarm data and different service data, so as to guarantee the low time delay transmission of the burst key service data. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is a flow chart of an alarm data low time delay transmission method suitable for a star type wireless ad hoc network in the specific embodiment of the present application;

[0022] Figure 2 It is a node time slot allocation principle diagram in the specific embodiment of the present application;

[0023] Figure 3 It is a gateway data forwarding principle diagram in the specific embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to make the above objectives, features and advantages of the present application more obvious and comprehensible, the specific implementation methods of the present application are described in detail below with reference to the drawings. In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, and therefore the present application is not limited to the specific implementations disclosed below.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0026] Figure 1 For a flow chart of a low-latency alarm data transmission method suitable for a star-type wireless ad hoc network in the specific implementation of the present application, as shown in Figure 1 the method steps include:

[0027] (1) The gateway and the nodes form a star-type ad hoc network through time-division multiple access, and the gateway allocates fixed communication time slots for the nodes;

[0028] (2) The gateway inserts dynamic time slots in the interval of the fixed time slots, and when the nodes have alarm data generated, the nodes transmit data to the gateway through the dynamic time slots;

[0029] (3) The gateway adopts a multi-key level data scheduling strategy to schedule the data, so as to ensure low-latency transmission of the alarm data.

[0030] In step 1, the nodes access the gateway through time-division multiple access, and the gateway divides fixed time slots for each node, as shown in Figure 2 the fixed time slot of a node includes an uplink time slot and a downlink time slot.

[0031] Further, assuming that the number of nodes is N, the uplink time slots are divided into N, which are used for the nodes numbered 1 to N to transmit data to the gateway; and the downlink time slots are set up every 1 uplink time slot, which are used for the gateway to transmit data to the nodes.

[0032] Further, the division of the uplink time slot and the downlink time slot of the node is to ensure the communication latency of the node while also taking into account the synchronous reception of the commands issued by the gateway among the nodes. Each node periodically transmits data to the gateway one by one through its own time slot in a polling manner; however, when issuing overall commands, the gateway simultaneously issues the commands to each node in a broadcast manner.

[0033] In step 2, in order to ensure low latency transmission of burst alarm data, on the basis of step 1, a dynamic time slot is inserted every M fixed time slots, as shown in Figure 2 A time slot cycle is composed of M fixed time slots and one dynamic time slot. The insertion principle of the dynamic time slot is as follows:

[0034] Suppose the uplink time slot time of each node is ΔT1, the downlink time slot time is ΔT2, the dynamic time slot time is ΔT3, and the required alarm data latency is Δt, then the following is required:

[0035] M(ΔT1+ΔT2)+ΔT3≤Δt

[0036] That is, a dynamic time slot for burst alarm data must be inserted within the required latency range.

[0037] Further, in the case where no alarm is generated, the node periodically transmits data according to the assigned fixed time slot, and when the node has burst alarm data, it finds the nearest dynamic time slot through competition to send data to the gateway.

[0038] Further, when the node has burst alarm data, the rules for competing for the dynamic time slot are as follows:

[0039] (1) Search for a dynamic time slot within the time slot cycle in which the node is located;

[0040] (2) Determine whether the dynamic time slot within the time slot cycle is occupied;

[0041] (3) If the dynamic time slot within the time slot cycle is occupied, wait for a random time until the dynamic time slot is released. In step 3, the gateway classifies the received data according to the urgency, as shown in Figure 3 The data is classified into critical level data and priority level data.

[0042] Further, the burst alarm data is classified into critical level data; the ordinary service data is classified into priority level data.

[0043] Further, according to different alarm conditions, the alarm data is further classified into critical level 1, critical level 2, and so on; according to the urgency of ordinary service data, the ordinary service data is further classified into priority level 1, priority level 2, and so on. Different levels of data have corresponding identification bits in the communication frame format, for example, critical level 1 is defined as 01, critical level 2 is defined as 02, and so on; priority level 1 is defined as 11, priority level 2 is defined as 12, and so on.

[0044] The gateway formulates the principle of forwarding data according to different levels as follows:

[0045] (1) key level data is directly forwarded;

[0046] (2) priority data is queued and forwarded.

[0047] Further, since the alarm data frame is usually short, a plurality of key level data can be combined and sent, further reducing the forwarding delay.

[0048] The above is only the preferred embodiment of the present application, and does not limit the present application. Any simple modification, change and equivalent structural change of the above embodiment according to the technical essence of the present application are still within the protection scope of the technical solution of the present application.

Claims

1. A low-latency transmission method of alarm data suitable for star-type wireless ad hoc networks, characterized in that, The method comprises the following steps: 1) the gateway and the nodes form a star self-organizing network, the gateway allocates fixed communication time slots for each node, and the nodes transmit data without alarm in the fixed time slots; 2) the gateway inserts dynamic time slots in the interval of the fixed time slots, and the nodes transmit alarm data to the gateway by competing for the dynamic time slots; the data transmission in the competing dynamic time slots is to insert a dynamic time slot for burst alarm data in a required time delay range; a dynamic time slot ΔT3 is inserted every M fixed time slots of the nodes, so that the alarm data time delay condition is met: M(ΔT1+ΔT2)+ΔT3≤Δt; wherein ΔT1 is the uplink time slot time of each node, ΔT2 is the downlink time slot time, ΔT3 is the dynamic time slot time, and Δt is the required alarm data time delay; 3) the gateway adopts a multi-critical level data scheduling strategy to schedule the data, so as to ensure low time delay transmission of the alarm data; the multi-critical level data scheduling is as follows: the gateway divides the received data into critical level data and priority level data according to the levels; the gateway forwards the data according to the data types and different levels; the forwarding method is that the critical level data is directly forwarded, and the priority level data is queued and forwarded. N uplink time slots are divided according to the number of nodes N, and are used for the nodes to respectively transmit data to the gateway; every 1 uplink time slot sets 1 downlink time slot, and is used for the gateway to transmit data to the nodes.

2. The low-latency alarm data transmission method for star wireless ad hoc networks according to claim 1, characterized in that, The burst alarm data is divided into critical level data of different levels; and the ordinary service data is divided into priority level data of different levels.

3. The low-latency alarm data transmission method for star wireless ad hoc networks according to claim 1, characterized in that, ​

Images