FPGA Based Rifle Uncooled Infrared Imaging Aiming System Design

Recently,with the development of uncooled infrared thermal imaging detection technique,such imaging detection is commonly used in the military and civil fields.Especially in the military field,rifle uncooled infrared imaging aiming system is of great research value,becoming a world-wide research topic due to its small volume,high dependability and low power.The main research contents of thesis include:(1)The background and recent progress of rifle thermal imaging system technique are introduced in details,and the operation principle of thermal imaging aiming system is explained as well.Meanwhile,the technique of field programmable gate array(FPGA)is introduced,including the related software and hardware description language.(2)We complete the hardware design of infrared imaging system,including power supply circuit,detector bias circuit,analog-to-digital(A/D)converter circuit,FPGA signal processing circuit and video coding circuit.We reasonably distribute the network of power supply system based on each device demand.The functions,operation flow and key technologies of signal processing circuit and detector drive circuit are presented.We carry out signal integrity analysis on key circuit modules and provide the rule constraints and design guidance for the printed circuit board(PCB)layout.(3)The key algorithms of infrared image processing are investigated.We selects a two-point correction algorithm according to the actual hardware requirements.For the blind element detection and compensation,we combine the requirements of both infrared detector blind element distribution and system real-time,the median filter algorithm based on the domain replacement algorithm is used for blind pixel compensation.An adaptive grayscale piecewise linear transformation algorithm is used to display the infrared images for the purpose of contrast ratio enhancement.