Synchronous Transmission-Based Scheduling Strategy For Industrial Wireless Networks

Industrial wireless networks are an emerging form of the Industrial Internet of Things(IIo T)that utilizes wireless communication technology to achieve networking and data transmission of field devices.In industrial wireless networks,data transmission needs to meet the requirements of reliability and real-time.If the data cannot be transmitted correctly to the receiving end before the deadline,it may cause serious damage to industrial production.The scheduling strategy of industrial wireless networks aims to allocate the channels and time slots in the network reasonably during data transmission to meet the aforementioned requirements.The scheduling strategy should ensure that the industrial wireless network avoids node or link conflicts during data transmission,achieving high reliability scheduling.Additionally,data packets must complete transmission before the deadline to avoid packet accumulation and meet the network’s real-time requirements.Designing scheduling strategies to allocate network resources and ensure network reliability and real-time is a challenge for achieving data transmission in industrial wireless networks.Traditional industrial multi-hop network scheduling strategies use a store-and-forward method to transmit data.However,in this method,the forwarding node must receive the entire data packet before it can forward it to the next hop,increasing the data packet transmission delay.Synchronous transmission can effectively solve this problem by allowing the forwarding node to forward the data in the form of a byte or bit stream instead of storing the entire data packet,thus significantly reducing the transmission delay of multi-hop transmission.Currently,centralized algorithms are mainly used to implement scheduling strategies based on synchronous transmission.However,centralized algorithms consume network resources to collect network information and send scheduling tables,and they have drawbacks such as single-point failure and poor scalability.Therefore,this paper proposes three distributed scheduling strategy methods based on synchronous transmission to meet the goals of reliable and real-time data transmission and conducts experimental simulations of the proposed methods.(1)For networks with nodes that have equal traffic,this paper designs a self-governing scheduling strategy based on synchronous transmission that can send data packets to the entire network within one time slot.Under this strategy,nodes can independently choose transmission time slots to achieve ordered and collision-free data transmission,achieving deterministic transmission.At the same time,this paper also designs channel switching mechanisms to enhance the network’s robustness,event stream preemption mechanisms to handle sudden event streams in the network,and node management mechanisms to deal with dynamic networks.Compared with the store-and-forward transmission method,this method has significant advantages and can greatly reduce delay.(2)For the problem of nodes with different traffic in heterogeneous networks,this paper proposes a flow negotiation scheduling method based on synchronous transmission.In this method,nodes negotiate based on the number of data packets to achieve dynamic updates of node order in the network.Nodes adjust node information dynamically based on network traffic to select the correct transmission time slot.The number of transmission time slots for each node is the same as its number of data packets,increasing the utilization rate of network time slots and reducing network delay.(3)For the problem of collecting data streams in industrial sensor networks,this paper studies a delay optimization method based on a token ring.This method uses the node’s minimum hop algorithm to calculate the number of hops from the node to the gateway to determine the packet sending time,effectively shortening the delay of data packet flooding.In addition,this paper stores the node’s transmission time in the token and uses the token ring to achieve ordered data packet transmission,avoiding conflicts between nodes.Simulation results show that scheduling strategies based on synchronous transmission have significant advantages over store-and-forward scheduling.They achieve lower delay and higher network reliability,making them suitable for data transmission in industrial wireless networks.