Realize the goal quick and accurate location when the detection signal is weaker, puts forward a Fast Intelligent Tracking algorithm(FITA) with the Gain Adjustable. Wiht the goal image move in four quadrant detector, it’s size, location and output signal related to a linear probe interval. In this interval, a liner relation can be get between the spot position and the corresponding output signal. The target quick location algorithm is realized with this relation. On the other hand, the sum signal of the four quadrant detector is sampled in real-time, this sum is related to the sensor’s signal strength, then the change rate of the signal strength can be get, using adaptive learning ways to get the change trend of signal strength, and realized dynamic adjustment of the signal gain, in order to improve the signal resolution ratio when signal is weak, the tracking accuracy can be improved with this way. The experimental data show that FITA algorithm can rapidly locate position in the linear interval and accurately track through the dynamic change signal gain for the weaker signal. The track error can be improved to 1.9%.
