Design Of Photodiode Array Detection And Signal Processing Circuits

In the range test technique, the projectile velocity measurement is an important index of guns and bullets performances. At present, the projectile velocity measurement method is usually used the zone-block test equipment,which the main types of photoelectric detection equipment include light screen and sky screen target etc. The sky screen target taking the sky as the background, is mainly used for measuring large calibre projectile. The detection sensitivity is influenced by the brightness of the sky, so, the sky screen target can be used only in the daytime. The light screen target with artificial light is not affected by the external environment, and has high detection sensitivity, but the target is only suitable for small caliber projectiles because of its small, detection target surface.The equivalent analyses are studied for the photoelectric detector based on the technology of XGK-2002 light screen in this paper. In order to achieve the detection target surface of 2m×2m, optimal arrangement of detectors is studied and the screen frequency response characteristics are ensured. The main contents in this paper include:(1) In this article, the photodiode equivalent circuit is analyzed, and the main factors restricting the screen on the receiving array length are discovered. On this basis, in order to achieve the optimization of photodiode array, the more optimized arrangement of the diode array is put forward by selecting the appropriate diode,, according to its main factors.(2) The signal processing circuit of light screen is designed. The photodiode output current signals with weak change are collected and amplified, the effective signal of the projectile through the target is output. The performance of light screen target function and frequency response characteristics is verified by firing practice.(3) Two kinds of cable fault detection schemes are put forward for often appearing cable fault in test process, which are offline cable detection and online detection. It provides technical support for the detection of cable in different situations.(4) Part of tests related the circuits of light screen target are designed at low temperature environment and the performance of circuits is verified.