CAN Bus Application Layer Process in Small Satellite

Data bus is the main information transmission between small satellite modules.Using field area bus to select suitable data bus standard,improving application design and reliability,and bringing industrial and commercial data bus technology into spaceflight are the development trend to data bus in small satellites.Control area network(CAN) bus in small satellite has three layers,physical layer,data link layer and application layer.The paper introduces the application layer of CAN bus in small satellite and the method to form the data transmitting frame;it also describes the setting of arbitration field,control field and data field.The paper gives a method of data sending and receiving based on the property of the multi-master.It also introduces the net data structure in data package and the positions of source address,and target address in CAN frame,designs every identify data(ID) segment,including priority,address,assistant type,and multiple frame mark,and forms the application layer into CAN frame.The paper advances a new method that uses the multi-master,based on the priority to receiving and sending data,and can satisfy the requirements of real time and large capacitance of data.