Research On Application Of Spaceborne Solid State Recorder File Management Scheme

With the continuous development of space science,the task of space exploration is gradually enriched,which presents new features such as rapid increase of payload performance and diversification of task form,which challenges the storage management mode of spaceborne solid state memory.The traditional on-board solid-state storage scheme was based on the design of data stream,and adopted fixed partition storage method,which has the disadvantages of poor flexibility and limited scope of application.Multi-source,multi-tasking,high-speed mass data and other characteristics of exploration tasks call for new storage management solutions to meet the needs of space missions.This paper mainly carries on the innovative researches of the file organization management strategy of payload data,the flexible dynamic storage scheme,the file reliable transmission protocol and other aspects,which aim to meet the requirements of high-speed multi-load data input,dynamic and flexible storage management.In order to achieve the parallel storage of multi-channel high-speed payload data,this paper analyzed the throughput bottlenecks of NAND FLASH-based solid-state memory,used a four-stage pipeline operation and a bus parallel expansion scheme,which improved the throughput and the storage capacity of the system.Meanwhile,this paper analyzed the shortcomings of the existed caching scenarios,and presented a high-speed multi-channel cache and storage cooperative scheduling scheme based on SDRAM,which implemented the high-speed data parallel receive cache and autonomous storage,eventually improved the system's payload support capability.In order to achieve the efficient file management of payload data,this paper analyzed the block device file system and the log structure file system,combed the need for spaceborne storage file management,extracted the key technologies of the new documented management system,and made a key design of FLASH free area,block usage table,block usage chain and the interrupt information interaction mechanism between hardware and software,finally proposed a new spaceborne solid-state storage file management scheme which based on the VxWorks embedded operating system and the FPGA hardware.Arms at the issue of the multi-file storage flexibility and the storage effective throughput,this paper presented a hybrid storage model of the autonomous virtual dynamic storage + fixed partition storage,which broke the boundaries of fixed partitions storage.Meanwhile,this paper presented a separate storage strategy of the scientific data and the file information,which ensured the high speed of data storage.This paper also implemented the physical layer of the schema architecture,completed the functional module division and hardware development of FPGA,eventually implemented functions of multi-channel high-speed data parallel receive cache,autonomous virtual dynamic storage and file playback,erase according to the instructions,etc.Arms at the efficient indexing and reliable operation of file systems,this paper presented an efficient indexing scheme of the tree directory index + file chain table,which supported the system to perform any on-demand playback,erase operation by directory,file and time.Meanwhile,this paper designed system management strategy such as bad block management,loss of balance,quick start and accidental power failure recovery,which improved the robustness of the system.This paper also designed the software of storage management,which implemented functions such as system initialization,file storage,file playback,and file erasure,etc.This paper finally established a scientific framework that meets the needs of space exploration missions,broke through the key technologies such as high-speed parallel buffering of payload data,autonomous virtual dynamic storage,file organization management and linked list fast index,implemented a reliable transport mode scheme for the CFDP file protocol,completed the development of the prototype model,solved the disadvantages of the traditional data organization and management mode,which has certain guiding significance to the practical engineering application.