The Real-Time Performance Optimization And Implementation Of Cyber Physical System Based On IEEE 802.15.4

Cyber physical system (CPS), which has been proposed recent year and considered as the third information technology wave after the computer and Internet technology, is attracting extensive concern of many academic scientific workers. Compared with the Internet, which has changed the communicating method among people, the birth of CPS is changing the contacting means between human and physical world and promotes the information interaction between the information world and the actual world. There is no doubt that it will bring many developing opportunities and challenges for us.Because of the advantages of low speed, low power consumption and low cost, the popular IEEE 802.15.4 protocol has the potential to be the wireless communication standards of CPS. It’s meaningful actually that the real-time performance of the IEEE 802.15.4 protocol will be improved. And before the improvement, the model was set up in OPNET simulation environment and the performance was re-estimated with the reference to some standards based on full understanding of the protocol. Aiming at the insufficiency of the protocol when it was established, a priority-based adaptive service-differentiation scheme, a collision-aware back-off mechanism and a delay sensitive time slot scheduling are introduced in improved protocol to strengthen the adaptive performance of the system, lower the delay and advance the bandwidth utilization respectively. Finally, the advantage in real-time performance of the proposed improved protocol is verified in OPNET by applying it to vehicle wireless sensor network.