Fig. 1. Schematic of solar vectors and polarized-light vectors

Fig. 2. Schematic of D, H, As and A's in carrier coordinate system

Fig. 3. Block diagram of overall structure of the system

Fig. 4. Real image of the hardware part

Fig. 5. Real image of the sun vector judgment module

Fig. 6. Direction of θi in the coordinate system

Fig. 7. Flow chart of system

Fig. 8. Test results of the sun vector judgment module. (a) Result of A's; (b) voltage of LG1

Fig. 9. A's and hs obtained by the sun vector judgment module

Fig. 10. Test results of positioning accuracy. (a) Test results about 55 minutes; (b) daytime test results