Research Of Small-Scale Infrared Imaging Pre-Processing Circuit Based On DSP And FPGA Devices

Infrared imaging pre-processing circuit as an important component of the Infrared Imaging System is used to achieve several functions,such as gathering analog video signals,achieving analog-digital conversion,achieving image information pre-processing and outputing images.This thesis offers a kind of imaging pre-processing circuit for infrared imaging system,based on DSP and FPGA devices.This circuit design starts from system requirement,then analyzes it to confirm system pre-processing circuit’s scheme and functional structure.This system uses TMS320C6414 of TI company and XC6SLX45 of XILINX company as the main devices to constitute imaging pre-processing circuit,which includes detector refrigerator smoothing control circuit,detector adaptation circuit,video signals conditioning circuit,image acquisition circuit,external interface circuit and system power supply circuit.According to the features of signal intensity and high speed signal transmission in imaging pre-processing circuit,it is easy to generate signal integrity and electromagnetic compatibility issues.This design focuses on these aspects.In signal intensity issue,aiming to solve signal transmission line reflections and signal crosstalk,this design uses the software of Hyper Lynx to run before-routing principle simulation and after-routing actual simulation to get improvement by adding circuit constraints.In electromagnetic compatibility issue,this circuit tries to meet design specification of electromagnetic compatibility and reduce interaction of electromagnetic interference in optimising devices layout,signal traces,source of interference isolation,interference ways blocking,and isolating sensitive signals.Achieving imaging pre-processing design and process adjustment,I used the system software to test all functions of the circuit including electromagnetic compatibility experiment.Including the test of video signal transmission processing channel,Two telemetry signal channels,Serial communication.DSP+FPGA circuits,Peripheral memory interface and system power test.All functions of the circuit system test are normal and meet the design requirements.And also finishing the Electromagnetic Compatibility test along with the system,the test projects include CE102、CE107、CS101、CS106、CS114、CS115、CS116、RE102、RS103,ESD electrostatic discharge.Most projects are normal,but CE102 and RE102 are exceeded.I gave initial analysis then offered improvement measures.On the whole,this pre-processing system meets the design goals.