FPGA Software Design Of A Space CMOS Camera

In recent years, CMOS camera has been widely applied in space remote sensingand monitoring of space as a new remote sensing imaging technique. The CMOS sensorby using the standard CMOS fabrication process and integrating AD converter anddriver circuit, is very conducive to the FPAG (Field Programmable Gate Array)operation on the pixel.FPGA, is a logic gate array edited component, and can be programmed by users.FPGA used a concept such as logic cell array LCA (Logic Cell Array), which includedthe internal interconnect (Interconnect), configurable logic module CLB (ConfigurableLogic Block) and output input module IOB (Input Output Block). FPGA developed onthe base of CPLD, PAL, GAL, FPGA must program the internal RAM, because theworking state of it is set by the program which is stored in the RAM chip. The userscan achieve different configuration mode through different ways of programming.FPGA direct continuously to high integration, high capacity, high speed, low powerconsumption, low price of the highest level of development, currently the highest levelof FPGA has already used65nm,11layers of copper wiring, and its scale has reached330000logic unit and the1200user I/O, the speed has reached550MHz, which makesFPGA more and more used in the design of spacecraft circuits.The paper designed and analysed the FPGA software for a CMOS camera,realized the CMOS interface driver, image acquisition, image cache compression anddata transmission, on the basis of analyzing of the FPGA’s characteristics and the taskdemands of the camera.According to the function of the camera, the FPGA software include CMOStiming, data acquisition, image compression, data output interface, the main controlmodule. It realized the automatic exposure control of CMOS detector in the controlmodule; and realized image compression based on8:1and2:1in the imagecompression process by the CDF9/7biorthogonal transform algorithm and SPIHTcoding method.The FPGA software passed the simulation and verification、static timing analysisand location imaging, it showed that the function of FPGA software can meet therequirements of the camera and the system runs steadily.