Analysis And Optimization Design Of The Real-time Performance For Wireless Sensor Networks

Wireless sensor networks (WSNs) integrated sensor technology, embedded computer technology, network and wireless communication technology, distributed information processing technology, etc. It can be through a variety of the micro sensor collaboration to achieve real-time monitoring, sensing and acquisition of various environmental or monitoring objects information, then it will process information through the embedded system, and by random self-organizing wireless network with multiple hops relaying mode transfer the perceive information to the data center. Wireless sensor networks have the features which are no need of fixed equipment supporting, and rapid deployment, self organization network, without wired network constraints. Wireless sensor networks can be used in every field of social information service, like as national defense and military, industrial control, urban transportation, large-scale public activities etc.The paper mainly researched real-time wireless sensor networks. The main factors of wireless sensor networks latency are a link delay and queuing delay. Analysis of simple priority scheduling algorithm, IEEE802.15.4 retreat strategy and algorithm of the agreement. Design the dynamic priority packet scheduling algorithm, and support priority of CSMA/CA algorithm, and use the OPNET simulating algorithm performance.Dynamic priority scheduling algorithm divided node buffer load to low, medium and high stages, classified routing information and data information to different priority groups, especially classified the data information into two priority groups. According to the change of node buffer system load, it improve the transmission performance of the network by dynamically adjust the routing packet priority. The simulation analysis shows that in the low load stage, dynamic priority scheduling algorithm and priority scheduling algorithm perform the same scheduling strategy, but due to the data packet priority setting, the data packet average delay is reduced; in the moderate stage, by lowering the level of some packets with the high priority, the average delay of data packet will reduce; in high load stage, adopt some discard strategy and priority assignment policy, will further reduce the average delay of the network.Support priority CSMA/CA algorithm, by setting the CW and BE to improve the transmission performance of the network. The simulation results show that the support priority CSMA/CA algorithm can improve the throughput and delay of high and middle priority packet, reduce the average delay. The algorithm by adjusting the CW and BE provided meet the requirements for business data real-time transmission service.