Design And Analysis Of Multi-channel MAC Protocol For Wireless Network

In recent years,the demand for wireless networks in various fields is increasing.The number of nodes deployed in the network is increasing,thereby increasing the demand for wireless bandwidth.Moreover,the transmission load in wireless networks is unstable.As the need for high data rate increases,the traditional single channel communication presents many problems,such as collision and interference,and the transmission failure due to these problems needs to retransmit the data packet,which requires more energy and increases the transmission delay.By using multi-channel communication,nodes that are closer can use different channels to achieve parallel communication,which can mitigate collision and interference,thereby reducing transmission delay and increasing network throughput.Therefore,designing a Medium Access Control(MAC)protocol with multi-channel communication for wireless networks has important theoretical and research value.Based on this background,this paper designs two multi-channel MAC protocols,the specific research contents are as follows:(1)This paper proposes a reservation-based and distributed multi-channel MAC protocol,called R-MMAC protocol.The reservation mechanism and the multi-channel communication mechanism are utilized.Under the multi-channel condition,each node will reserve the transmission of the next data packet when transmitting the data packet,and select the best channel according to the received signal strength indication(RSSI).The reserved transmission time is obtained by using the signal to interference and noise ratio(SINR)and the packet reception rate(PRR).In addition,a solution algorithm for collision during reservation is proposed,which reduces the transmission delay of the sensor node to the sink node and the collision probability of future data packets,and improves the throughput of the network.We used the OMNET++ 5.3 simulation tool to compare the R-MMAC,X-MAC and EM-MAC protocols.The results show that the R-MMAC protocol achieves lower end-to-end delay and higher throughput performance.(2)This paper proposes a multi-channel MAC protocol for adaptive transmission load,called HY-MMAC.The protocol implements an adaptive transmission load using a carrier sense multiple access(CSMA)mechanism and a time division multiple access(TDMA)mechanism.When the network load is light,the simple node uses the CSMA technology to contend for the channel to achieve transmission with the router.When the network load is heavy,parallel transmission is performed on multiple channels by using contention-free TDMA technology,which effectively alleviates channel contention.In addition,the full-duplex(FD)mode is used to explore the transmission opportunities of the exposed terminals and solve the collision caused by hidden terminals.This paper compares IEEE 802.11,DCA protocol and HY-MMAC protocol with OMNET++5.3,and finds that HY-MMAC protocol has certain advantages in total throughput and packet delivery rate.