Fig. 1. Flight full process model of UAV swarm targets

Fig. 2. Atmospheric transmission spectrum in mid infrared band^[14]

Fig. 3. Target imaging model

Fig. 4. Infrared radiation characteristics of UAV swarm. (a) Simulation diagram of skin spectral radiation intensity; (b) simulation diagram of infrared radiation intensity of nozzle; (c) simulation diagram of tail flame radiation intensity; (d) simulation diagram of total infrared radiation intensity

Fig. 5. Target infrared images and three-dimensional images. (a1)(a2) Single target; (b1)(b2) multi targets; (c1)(c2) single background; (d1)(d2) complex background; (e1)(e2) no target crossing; (f1)(f2) target crossing; (g1)(g2) target flying for small distance; (h1)(h2) target flying for large distance

Fig. 6. UAV swarm infrared images and three-dimensional images. (a1)(a2) Phase of formation flight; (b1)(b2) phase of group attack

Fig. 7. Target diffusion patterns under different coordinates

Fig. 8. Image plane energy distribution of target

Fig. 9. Transmission under different height

Fig. 10. Variation of detection distance under different models. (a) Variation of detection distance with R_SNR under different models;(b) variation of detection distance with UAV swarm speed under different models

Fig. 11. Variation of detection distance under different dispersion coefficients. (a) Variation of detection distance with R_SNR under different dispersion coefficients; (b) variation of detection distance with UAV swarm speed under different dispersion coefficients