Fig. 1. NLOS UV communication model
Fig. 2. UV beacon communication model. (a) Two-dimensional model; (b) three-dimensional model
Fig. 3. Communication coverage of a wireless UV beacon node in two- and three-dimensional spaces. (a) Two-dimensional space; (b) three-dimensional space
Fig. 4. Four-node positioning model
Fig. 5. Movement status of two drones
Fig. 6. Vector sharing method for collision avoidance
Fig. 7. Received signal strength of four ranging methods
Fig. 8. Received signal strength of different transmitting and receiving angles under NLOS
Fig. 9. UV ranging error at different ranging modes
Fig. 10. Positioning results of two- and three-dimensional spaces. (a) Two-dimensional space; (b) three-dimensional space
Fig. 11. 2D and 3D spatial positioning accuracy
Fig. 12. Two UAV collision avoidance paths
Fig. 13. Distance between two UAVs
Parameter | Value |
---|
Wavelength λ /nm | 255 | Average power Tx /mW | 50 | Effective areaAr /mm | 8×24 | Typical Gain ofPMT G | 107 | Quantum efficiencyηr /% | 25 | Beam divergence angleof the transmitter ϕ1 /(°) | 6 | Field of View ofthe receive ϕ2/(°) | 80 | Atmospheric absorptioncoefficient Ka /km-1 | 0.74 | Mie scattering coefficientKm/km-1 | 0.25 | Rayleigh scatteringcoefficient Kr/km-1 | 0.24 | Atmospheric scatteringcoefficient Ks/km-1 | 0.49 | Atmospheric extinctioncoefficient Ke/km-1 | 1.23 |
|
Table 1. System model parameters