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U. (2002). Probability, Random Variables and Stochastic Processes, 4th ed. 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(4)–(6): advection fog σ = (0.11478 λ + 3.8367)/V, λ in µm, V and σ per km.","basis":"computed","tolerance":1e-8,"inputs":{"model":{"value":"advection"},"visibility":{"value":0.5,"unit":"km"},"wavelength":{"value":1550,"unit":"nm"},"range":{"value":1,"unit":"km"}},"outputs":[{"key":"extinction","label":"Extinction σ (e-folds of power per length)","unit":"km⁻¹","expected":8.029218,"model":8.029217999999998,"relativeDifference":2.220446049250313e-16,"pass":true},{"key":"specificAttenuation","label":"Specific attenuation 10 log₁₀(e) σ","unit":"dB/km","expected":34.870450713982635,"model":34.87045071398263,"relativeDifference":2.220446049250313e-16,"pass":true},{"key":"pathLoss","label":"Path loss over the range","unit":"dB","expected":34.870450713982635,"model":34.87045071398263,"relativeDifference":2.220446049250313e-16,"pass":true},{"key":"transmittance","label":"Transmittance over the range","unit":"%","expected":0.03258028871860372,"model":0.03258028871860378,"relativeDifference":1.9984014443252818e-15,"pass":true}],"pageUrl":"https://photonicscalculators.com/free-space-comms/fog-attenuation?model=advection&visibility=0.5&wavelength=1550&range=1","apiUrl":"https://photonicscalculators.com/api/v1/free-space-comms/fog-attenuation?model=advection&visibility=0.5&wavelength=1550&range=1"},{"source":"Kim I. I., McArthur B., Korevaar E. (2001). Comparison of laser beam propagation at 785 nm and 1550 nm in fog and haze for optical wireless communications. Proc. SPIE 4214, 26–37: σ = σ_R + [3.912/V − σ_R(550 nm)](λ/550 nm)^(−q), Rayleigh part from Bucholtz A. (1995). Appl. Opt. 34(15), 2765–2773, eqs. (2)–(4).","basis":"computed","tolerance":0.000001,"inputs":{"model":{"value":"kim"},"visibility":{"value":2,"unit":"km"},"wavelength":{"value":850,"unit":"nm"},"range":{"value":3,"unit":"km"}},"outputs":[{"key":"extinction","label":"Extinction σ (e-folds of power per length)","unit":"km⁻¹","expected":1.460910751740203,"model":1.460910751740203,"relativeDifference":0,"pass":true},{"key":"specificAttenuation","label":"Specific attenuation 10 log₁₀(e) σ","unit":"dB/km","expected":6.344654780339015,"model":6.344654780339015,"relativeDifference":0,"pass":true},{"key":"pathLoss","label":"Path loss over the range","unit":"dB","expected":19.033964341017047,"model":19.033964341017043,"relativeDifference":2.220446049250313e-16,"pass":true},{"key":"exponentQ","label":"Size-distribution exponent q (Kim, Kruse only)","unit":"","expected":0.66,"model":0.66,"relativeDifference":0,"pass":true}],"pageUrl":"https://photonicscalculators.com/free-space-comms/fog-attenuation?model=kim&visibility=2&wavelength=850&range=3","apiUrl":"https://photonicscalculators.com/api/v1/free-space-comms/fog-attenuation?model=kim&visibility=2&wavelength=850&range=3"},{"source":"Kruse P. W., McGlauchlin L. D., McQuistan R. B. (1962). Elements of Infrared Technology. Wiley, as reproduced in Nadeem F., Leitgeb E. (2010). Radioengineering 19(2), 223–227, eqs. (1)–(3): q = 0.585 V^(1/3) for V < 6 km.","basis":"computed","tolerance":0.000001,"inputs":{"model":{"value":"kruse"},"visibility":{"value":0.5,"unit":"km"},"wavelength":{"value":1550,"unit":"nm"},"range":{"value":1,"unit":"km"}},"outputs":[{"key":"extinction","label":"Extinction σ (e-folds of power per length)","unit":"km⁻¹","expected":4.829279725410907,"model":4.829279725410907,"relativeDifference":0,"pass":true},{"key":"specificAttenuation","label":"Specific attenuation 10 log₁₀(e) σ","unit":"dB/km","expected":20.973295363132078,"model":20.973295363132078,"relativeDifference":0,"pass":true},{"key":"pathLoss","label":"Path loss over the range","unit":"dB","expected":20.973295363132078,"model":20.97329536313208,"relativeDifference":2.220446049250313e-16,"pass":true},{"key":"exponentQ","label":"Size-distribution exponent q (Kim, Kruse only)","unit":"","expected":0.46431480770069833,"model":0.46431480770069833,"relativeDifference":0,"pass":true}],"pageUrl":"https://photonicscalculators.com/free-space-comms/fog-attenuation?model=kruse&visibility=0.5&wavelength=1550&range=1","apiUrl":"https://photonicscalculators.com/api/v1/free-space-comms/fog-attenuation?model=kruse&visibility=0.5&wavelength=1550&range=1"}]}]}