Design And Implementation Of Spaceborne Infrared Small Target Detection System Based On FPGA

With the continuous development of satellite technology,satellite-borne infrared target detection system plays an increasingly important role in military and civil fields.However,because the background of satellite infrared image is complex and the target point is small,the difficulty of detection is increased.Moreover,the high resolution and frame rate of satellite image result in high data rate of on-board Information processing,which puts forward higher requirements for real-time and stability of the system.The purpose of this paper is to design and implement a spaceborne infrared small target detection system with good detection performance,real-time performance and high stability.The research includes the optimization of infrared small target detection algorithm,the realization of the algorithm on FPGA and the design of system interface.First,we use the infrared small target detection algorithm based on the annular maximum median filter and inter-frame trajectory correlation.In order to make use of the parallel execution characteristics of the FPGA,we simplify the complex computation and optimize the computing structure to make it suitable for the implementation on the FPGA on the premise that the detection performance of the original algorithm is less affected.The methods include simplifying the calculation of threshold,calculating the current frame threshold based on the last frame statistics,loop unrolling for multi-frame detection and so on.Then,we design the hardware structure of the algorithm implemented on the FPGA based on the idea of parallelization and pipeline processing,including the modules of annular maximum median filter,threshold calculation,adaptive threshold segmentation,multi-frame detection,detection results access,connected component labeling and target centroid calculation.The design has the characteristics of“global pipeline and local parallelism”,and has strong real-time performance.Finally,we design the interface of infrared small target detection system,including clock and reset,image data input interface,result output interface,DDR interface,telemetry and telecontrol interface.The stability of the system is guaranteed from timing constraints,asynchronous processing and protocol design.In this paper we use Xilinx XC5VFX130T as the core processor of spaceborne infrared small target detection system.The detection performance of the system is good when the target local signal-to-clutter ratio is not less than 6,in which case the detection rate is more than 95%and the false alarm rate is less than 1×10^-5.For images with a size of 2800×2800 and a data bit width of 14 bits,the maximum processing rate of the infrared small target detection module can theoretically reach 12.5 frames/s with a processing clock of 100 MHz,which has high real-time performance.