To solve the uncertainty of time delay existing in arbitrated loop and switched topology of FC-AE-1553, a novel bus structure based on passive optical network was proposed which insures the confirmation and real-time performance. Transmission delay time for each message on bus is extremely certain in which the mechanism is broadcast in the downstream direction and time sharing in the upstream direction. FC-AE-1553 based on bus topology can support users to arrange task according to bus timing and it is suitable for application in aerospace and other hard real-time environment.