Dynamic Scheduling Mechanism Research Ofapplication In FC-AE-1553 Switching Network

With the development of the national aerospace science and technology strategy,the application information system become the important and indispensable part of Avionics systems. Many science experiments and application payload are increased with the scientific research and application development requirements.Therefore higher demands are proposed for application system in the aspects of network transmission, data processing and storage. Traditional MIL-STD-1553B is widely used in avionics systems for its characteristics such as simple network, but its transmission capacity and reliability are all can't satisfy the requirement of the new generation avionics system transmission.However FC-AE-1553 as one of the protocols FC-AE is considered as the candidate protocol of aerospace due to the high real-time,high-bandwidth,high reliability and compatible with MIL-STD-1553B.Research and design have been done in this paper on FC-AE-1553 switching network scheduling mechanism and high precise time synchronization method, the main research contents and results of the study are summarized as follows.1. This paper established the multi-node to multi-node scheduling model for the scheduling problem fo multiple application data in FC-AE-1553 switching network and proposed a hybrid bandwidth allocation algorithm based on parallel scheduling which fits the multi-traffic demand. Then the FC- AE-1553 switching network simulation platform was built based on OPNET, based on it we made detail simulation verification and analysis of proposed scheduling mechanism. Simulation result showed that hybrid bandwidth allocation algorithm based on parallel scheduling improved the bandwidth utilization to 83% and guarantees the delay demand of multi-traffic data compared to non-parallel scheduling algorithm.2. In order to solve the multiple application data scheduling problem in FC-AE-1553 multi-level switching networks,we proposed a caching scheduling mechanism.It has lower control complexity and overhead,higher bandwidth utilization compared to distributed scheduling and centralized scheduling mechanism.We built FC-AE-1553 multi-level switching network simulation platform based on OPNET and simulated the caching scheduling mechanism in detail. Simulation proved that th proposed scheduling mechanism completed the multiple application data in multi-level switching network effectively and bandwidth utilization reached to 80%.3. For the time synchronization requirements in FC-AE-1553 network,this paper design a time synchronization scheme which the nodes have a asynchronous clock.Then we verified and tested time synchronization accuracy based on FPGA in th FC-AE-1553 point to point structure. Test results show that the time synchronization accuracy of scheme is 60 ns when the synchronous period is set as 100 ms in point to point structure.Because there are at most three boundary clock between master and slave node,the synchronization accuracy meet the design requirements which is less than 1us.