Four-quadrant Detector Laser Detection And Positioning Study

Four-quadrant detector is photoelectric position sensor, which is based on photoemission. It is widely used in object position-sensitive detecting and laser terminal guidance ammunition.Four-quadrant photoelectric diode is the key component of laser guidance weapon. In this dissertation, the operation principle is explained, also the structure of diode, sensitivity degree, and noise current are analyzed. At the same time, the background light influences on four-quadrant detector were also analyzed in detail in theory. Some research work of anti-jamming of the four-quadrant photoelectric detector was done, and several measures of decreasing background interference were proposed. And then, the localization algorithm of four-quadrant photoelectric was particularly analyzed. The advantages and disadvantages of all kinds of algorithms are compared. The corresponding signal-gathering circuit and target-detecting circuit were designed, including a low noise photoelectric circuit which was used to gather" the guiding laser pulse signal. And in order to enhance the system's signal to noise ratio, a correlated synchronal detecting scheme was introduced.A singlechip ADuC841 was used to gather the photoelectric signal. The periphery circuit of the singlechip was designed and the program was compiled. The singlechip computes the position coordinates of the target. Searching and tracking of the guiding laser facula is achieved.