Design Of Infrared Video Signal Test System Based On FPGA

FPGA has the advantages of high flexibility,and integration,can work in parallel mode,and is suitable for the small-scale image signal system design.In order to facilitate the test of the function and performance of the infrared video signal processing circuit system,this paper designs a set of image signal test subsystem dedicated to facilitate the signal processing circuit to provide the signal source and to simulate the output signal of the focal plane circuit during the test.The system uses Xilinx V5 series XC5VFX130 T type FPGA as the main control chip,mainly for the signal processing circuit to provide image signal source,simulation of five long and short wavelength output signal function.The specific data processing process is: after reading the DDR2 SDRAM data on off-chip cache,the data cache in the dual-port RAM,through the data bit width conversion to extract the original data,and the original data for data gain,and finally through the double Port RAM pingpong cache,to achieve data across the clock domain transmission,the external circuit to provide long and short wavelength sequence,the output of 5 long and short wavelength output signal.In the system design,first select the appropriate FPGA and off-chip cache DDR2 according to the requirements.According to the data processing process,the design is divided into clock generation module,enable and line synchronization signal generation module,data read and distribute module,data cache module,data A bit-width conversion module,a data gain module and a data output module,respectively,to complete the clock signal generation,data cache read and distribute,data bit width conversion and gain,input and output data across the clock domain transmission function.The system has a maximum cache capacity of 8 Gbits and the FPGA crystal is 100 MHz.After the Modelsim software simulation and Chipscope online hardware debugging results show that,the system can be stable transmission of long and short wave digital signal data;2 long-wave signal output frequency of 2M,3-way short-wave signal output frequency of 4M;support the gain adjustable to meet the design requirements.