Fig. 1 The gain pattern of the H-field loop antenna
Fig. 2 Simulation configuration
Fig. 3 TOA-based Loran ASF of Case 1 (a) 9930M (b) 9930W (c) 7430M (d) 7430X (e) 7430Y
Fig. 4 TOA-based Loran ASF sorted by H-field antenna’s heading (a) 9930M (b) 9930W (c) 7430M (d) 7430X (e) 7430Y
Fig. 5 TOA-based Loran ASF of Case 1 with corrected estimated directional ASF of H-field antenna (a) 9930M (b) 9930W (c) 7430M (d) 7430X (e) 7430Y
Fig. 6 TOA-based Loran ASF of Case 2 (a) 9930M (b) 9930W (c) 7430M (d) 7430X (e) 7430Y
Fig. 7 TOA-based Loran ASF of Case 2 with corrected directional ASF modeling (a) 9930M (b) 9930W (c) 7430M (d) 7430X (e) 7430Y
Fig. 8 TOA-based Loran ASF over heading(blue) and the directional ASF modeling(red) (a) 9930M (b) 9930W (c) 7430M (d) 7430X (e) 7430Y
Photo 1 Experimental setup for field test
Fig. 9 The trajectory of the field test using ground vehicle
Fig. 10 TDOA-based Loran ASF of field test (a)7430M-9930M (b)7430M-9930W (c)7430M-7430X (d)7430M-7430Y (e)7430X-7430Y (f)7430X-9930M (g)7430X-9930W (h)7430Y-9930M (i)7430Y-9930W (j)9930M-9930W
Fig. 11 TDOA-based Loran ASF sorted by H-field antenna’s heading(blue) and directional ASF(red) (a)7430M-9930M (b)7430M-9930W (c)7430M-7430X (d)7430M-7430Y (e)7430X-7430Y (f)7430X-9930M (g)7430X-9930W (h)7430Y-9930M (i)7430Y-9930W (j)9930M-9930W
Fig. 12 TDOA-based Loran ASF of field test with corrected directional ASF modeling (a)7430M-9930M (b)7430M-9930W (c)7430M-7430X (d)7430M-7430Y (e)7430X-7430Y (f)7430X-9930M (g)7430X-9930W (h)7430Y-9930M (i)7430Y-9930W (j)9930M-9930W
Fig. 13 The horizontal error of TDOA-based Positioning with directional ASF correction(red) and without directional ASF correction(blue)
Table 1 The parameter settings for the H-field antenna’s directional characteristics
Table 2 Improvement of TDOA-based directional ASF correction
참고문헌
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