Design And Implementation Of High-speed High-reliable Miniature Digital Video Storage System

In weapon tests,the optical measuring device is not only to obtain the testingparameters such as the outside ballistic trajectory and the flight path of targets, butalso to acquire accurate flying attitude parameters, optical parameters and moreconventional measurement parameters. These parameter measurements depend on abig area array and high frame camera which can get high speed imaging informationand measurement information by tracking equipment from different angles. It has toput forward higher requirements to the real-time recording of high speed image andsynchronization measurement information. So the research of high-speed storagesystem with reliable performance,small size and large capacity, becomes the urgentneed to develop. The storage system is suitable for the large scale photoelectrictheodolite, can also apply to the aerial survey image, weather radar, remote sensing,explosion experimentation, fluid experimentation and collision detection.The main research contents of this paper aim to solve the contradiction ofhigh-speed data and low transmission speed storage devices, to the problems of thesame frame control of image and different source information, embedded Linuxsystem transplantation, system miniaturization, error correcting encode of image data,wear leveling of memory medium, and so on. System has achieved a highly reliablehigh-speed data storage and device miniaturization. Direct storage solution of the DM8168and FPGA combination is used inembedded system hardware platform. It can avoid the bottleneck of thenon-real-time operating system and computer architecture, and complete thecollection, storage and network transmission of data flow control, only by the twochips. It reduces the chip cascade, lowers hardware average failure rate and achievesthe miniaturization of the system. Integration strategy is adopted to superimposedifferent source information and image data with a frame, so as to ensure additionalinformation and image data fusion stored strictly in the same frame.Combining with the two-dimensional characteristics of an image, this paperdesigns a real-time two-dimensional RS encode algorithm, and corrects errors in twodimensions. The algorithm improves the ability of the system to correct the bursterrors and random errors. At the same time, this paper also proposes acquisition errorcorrection and image features error correction method, to ensure that the frame iscorrect and integrated. The reliability of data storage is improved by implementingdata error correction, frame correction and line correction.In order to ensure the stable operation of Linux system, this paper transplantsthe embedded Linux system, and adds the necessary driver, cuts down irrelevantmodules in system. System adopts balance management method for SSD which isbased on the write address sequence, writes image data by traversing mappedaddress, achieves wear leveling of the SSD, and extends the life of the SSD. Thispaper presents the idea that controls the physical address of the mechanical diskdirectly and writes or reads data cycle by cycle. The mentioned method can reducethe disk seeking time, and improve the storage speed.When embedded Linux used in DM8168manages the tasks of system, it breaksthe limitation of file system in hard disk. Disk file allocation table parameter is put inan external FRAM, which is independent record outside the storage medium. Thedesign reduces the operating cost of the Linux kernel on the hard disk file system.On the one hand, it is convenient to recover the mechanical disk data, on the otherhand, it solves the problem that solid-state hard disk file mapping table needs to wear leveling. It is helpful to improve system reliability.The storage system unit researched in this paper can effectively receivehigh-speed data from camera at the speed of400MBps, greatly improve theefficiency of storage, and achieve the miniaturization of the equipment. Comparedwith one-dimensional RS encode method, the ability of Block two-dimensional RSencode improves1.97times. The bit error rate is1.01E-11. Embedded system designrealizes task management, remote downloading and system online maintenance.According to the practical application of project, this paper can satisfy the need ofstorage in various fields by the technology of data assignment for high frame cameraafter expanding storage system unit.