Electrical Design Of High Speed And High Quality Space CMOS Camera

Remote sensing is the core of space exploration,and space camera is the bright and sharp eye of space.The traditional visible light space camera is usually CCD camera,and the CCD camera has high imaging quality,but the imaging circuit is complex.It is required to be equipped with driving circuit,A/D conversion circuit and readout circuit,which leads to the larger size and power consumption and higher cost of the camera.In recent years,CMOS sensor manufacturing technology has been improved,image processing algorithms are becoming more and more mature,and the imaging quality of CMOS sensors is becoming higher and higher.CMOS cameras are gradually applied to the field of space detection.The research works mainly including following contents:(1)Introduce the development process of CMOS image sensor,the classification of CMOS image sensor,and compare the sensing performance of CCD and CMOS.Introduce the structure and working principle of CMOS image sensor,and the advantages and disadvantages of CMOS camera and its future development prospect.(2)The overall design of the CMOS space camera is carried out.According to the electronic index of the camera,the IA-G3 image sensor is selected and the imaging spectrum of the camera is designed.According to the imaging conditions,the F number and exposure time of the camera are designed.According to the timing characteristics of the CMOS sensor,the circuit architecture of the CMOS+FPGA is selected and the camera is designed as the three boards of the focal plane circuit,signal processing circuit and interface circuit.Finally,selected the electronic components.(3)Completed the selection of circuit components,and explained the main features of each component.The circuit principle design of each circuit board is completed,and the hardware design principles including IA-G3,FPGA and SDRAM are explained in detail.The electrostatic protection design and the reduction design of the circuit are completed.The conclusion that the circuit electrostatic protection design meets the requirements is obtained.The circuit meets the condition of the first order reduction.The design of high-speed PCB circuit is completed.The design of high speed PCB is strictly in accordance with impedance matching principle and wiring constraint.After testing,the quality of high-speed signal is excellent.(4)According to the timing characteristics of components,the driver of the circuit is written in Verilog language.Based on the normal imaging of the camera,the automatic exposure algorithm and the automatic white balance algorithm are programmed to improve the quality of the imaging.In this paper,we choose the IA-G3 CMOS sensor to design the high-speed and high quality CMOS space camera.The architecture of FPGA+CMOS is used to design the circuit of the focal plane,signal processing circuit and interface circuit,and the circuit drive,automatic exposure algorithm and automatic white balance algorithm are designed to make the high-speed transmission of the camera meet the high quality at the same time.The experiment results show that the design is reasonable and feasible,the stability of the circuit is high,the automatic exposure algorithm and the automatic white balance algorithm are reliable,and the camera completes the high speed and high quality imaging task.