Fig. 1. Frequency features of daytime beacon. (a) Simulation image of high intensity beacon; (b) frequency-domain response corresponding to Fig. 1(a) versus central distance; (c) simulation image of low intensity beacon; (d) frequency-domain response corresponding to Fig. 1(c) versus central distance

Fig. 2. Comparison of filtering response between with and without beacon light. (a) Without beacon; (b) with beacon

Fig. 3. Band pass filter response under special working condition. (a) Simulation image; (b) response image

Fig. 4. Flow of proposed algorithm

Fig. 5. Simulation maps

Fig. 6. Simulation image error. (a) Mean error of all background; (b) error of background 1 of Fig. 5

Fig. 7. Testing system and environment. (a) Testing system; (b) schematic of testing environment

Fig. 8. Photo of beacon

Fig. 9. Actual tracking result and fitting value in x direction. (a) Actual tracking results and fitting value; (b) fitting error

Fig. 10. Dynamic tracking error