Research On Multi-Radio Multi-Channel Wireless Sensor Networks MAC Protocol

Wireless Sensor Networks(WSNs)is the core technology of underlying data acquisition of the Internet of Things(IoT).The IoT proposal and technology development make the WSNs ushered the development "spring" and extensively use in some emerging areas,such as internet of vehicles,smart city and industry 4.0 etc.The traditional WSNs which used the single radio single channel or single radio multi-channels hardly meet the higher requirement for network performance in the emerging applications,for example require higher real-time performance of data transmission in industrial detection and control.The technology of multi-radio multi-channel is regarded as the promising way for improving the network performance.The Medium Access Control(MAC)protocol which is the link between the physical layer and upper layer protocols plays an important role in achieving the channel resource equalization and efficient allocation,fast access network of new nodes,reliable data transmission,optimization the nodes energy consumption.Furthermore,it is critical to improve the real-time performance of data transmission.In this paper,the MAC protocol of multi-radio multi-channel WSNs(MRMCWSNs)is deeply studied to achieve the multiple orthogonal and non-overlapping channels efficient and fair allocation and access,reduce the energy consumption and data latency,optimize the management of multi-radio multi-channel resource,and improve the network performance.Firstly,aiming at the problems of the multiple orthogonal and non-overlapping channels fair and equalization allocation,and diverse and parallel access,based on the pseudo-random sequence and Galois field this paper designs the multi-radio multi-channel allocation and channel-hopping mechanism,pseudo-random virtual time slot wake-up sequence and multi-radio multi-channel parallel communication strategy.It realizes that the each channel-hopping sequence of multi-radio nodes is uniqueness and every one non-overlapping and orthogonal channel is accessed once and only once in one hopping cycle.Moreover,it guarantees that the allocation and access of multiple non-overlapping and orthogonal channels are balance and efficient.In addition,the diverse and parallel communication mechanism which solves the terminal hiding problem and improves the transmission efficiency and data latency is presented based on the proposed channel allocation scheme.At the same time,for the clock drift problem caused by hardware crystal aging and production inconsistency,the random weighted averaging algorithm based data transmission time estimation and time calibration strategies between nodes are studied.The algorithm can reduce the estimation error that caused by data delay or packet loss and increase the accuracy of time switch when the multi-radio nodes channel hopping.xSecondly,for the energy consumption problem of multi-radio node in the proposed MRMCWSNs MAC protocol packet parallel communication process,the energy efficient task scheduling algorithm based on simulated annealing is proposed.The energy consumption model of multi-radio node in packet parallel communication is built and then the minimization the energy consumption of node is regarded as the optimization objective function.Then using the simulated annealing algorithm to search the energy optimal task scheduling results,in order to reduce the energy consumption and prolong the network lifetime.Again,in order to realize the optimal scheduling of multi-radio resource in MRMCWSNs,the interval type-2 fuzzy logic system(IT2FLS)is introduced and applied in the optimal radio making decision of multi-radio node communication process.The models including channel quality estimation,transceiver energy dissipation and residual energy of node are built firstly and then used them as type-2 fuzzy input variables of the proposed multi-radio scheduling scheme based on IT2FLS.The optimal transceiver for multi-radio node communication is calculated according to the designed fuzzy rules and fuzzy inference engine.The selected transceiver has optimal data transmission success rate,the lower energy consumption and data latency,since the transceiver decision process takes the channel quality,energy consumption of transceiver and the current residual energy of multi-radio node into consideration.The proposed IT2FLS based multi-radio resource optimal scheduling and management mechanism is conducive to exert the advantage of multi-radio multi-channel MAC protocol and largely improve the network performance of MRMCWSNs.Finally,the periodic real-time parallel transmitted data scheduling' delays including the channel conflict delay caused by carry-in packet and channel contention delay caused by non-carry-in packets are analyzed in detail under constrained condition.Then combine the two types delay together to obtain the upper bound of communication delay under the constrained condition providing theoretical guidance for analyses the schedulability of periodic real-time data parallel transmission and dynamic adjustment the network load of each transceiver.When the data transmission delay of anyone transceiver equipped on a same multi-radio node exceeds the upper bound of delay limitation and no longer meet the constrained condition,the multi-radio node can dynamically adjust the data load of each transceiver,so that the data transmitted by this transceiver can meet the real-time requirement.