Study On UV - Ignition Technology Of Sun - Blind

The solar-blind ultraviolet detection technology has an important application in military fields. A large amount of ultraviolet rays are emitted from the exhaust plume when the missile and aircraft flying in high speed. The solar-blind detection at low altitude can detect target without the interference of sun. This method has high signal-to-noise ratio and reduces the difficulty of signal processing. Using new photoelectric sensor to detect exhaust plume at solar-blind ultraviolet band becomes a trend with the development of wide band-gap semiconductor technology.Firstly, the mechanism of missile plume radiation, ultraviolet radiation transmission and key factors of UV detection system are analyzed. UV transmittance and solar irradiance in atmospheric environment are calculated through Modtran software. The mechanism of missile plume radiation in solar-blind spectrum is described. The major source of solar-blind radiation is chemical fluorescence radiation and hot particles. The model for radiation intensity and system detection distance is built. Key factors of system are analyzed based on the obtained model. Secondly, detection circuit is designed based on photoelectric sensor and circuit noise. The upper computer and lower computer of system are built to process the signal. Adaptive filtering technique is studied in order to remove the correlated noises in the signal. The LMS and RLS algorithms are analyzed based on Wiener filter. Algorithms simulation and noise signal processing are completed through MATLAB software. Finally, the designed detection system is used for experiment. The noise of the atmospheric background is analyzed. The simulated target and rocket flame are detected. According to theory analysis and experiment， solar-blind ultraviolet detection has high SNR. The system can detect target in the short range. The system is affect by the sealing of sensor, cutoff characteristic of filter and the interior noise of electric circuit.This article focused on a design method of system. It will provide theoretical reference and technical support to the solar-blind UV detection technology.