33 lines
1.5 KiB
Matlab
33 lines
1.5 KiB
Matlab
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%Dobson's model to calculate the real and imaginary part of moist soil
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%[1] Dobson, M. C., et al. (1985), Microwave Dielectric Behavior of wet
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%Soil-Part II: Dielectric Mixing Models, IEEE Trans. Geosci. Remote Sens.,
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%GE-23(1), 35-46.
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%[2] Peplinski, N. R., et al. (1995), Dielectric properties of soils in the
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%0.3-1.3-GHz range, IEEE Trans. Geosci. Remote Sens., 33(3), 803-807.
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%[3] Klein, L., and C. Swift (1977), An improved model for the dielectric
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%constant of sea water at microwave frequencies, IEEE Trans. Antennas
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%Propag., 25(1), 104-111.
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%[4] Stogryn, A. (1971), Equations for Calculating the Dielectric Constant
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% of Saline Water, IEEE Trans. Microwave Theory Tech., 19(8), 733-736.
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function [dcsr dcsi]=Dobson(f,T,smc,bd,vsand,vclay)
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alpha=0.65;
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dcs=4.7;
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sd=2.65;
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dc0=0.008854;
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dcw0 = 88.045-0.4147.*T+6.295e-4.*T.^2+1.075e-5.*T.^3; % Refer to [3]
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tpt=0.11109-3.824e-3.*T+6.938e-5.*T.^2-5.096e-7.*T.^3; %2*pi*tao, Refer to [4]
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dcwinf=4.9;
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if f>=1.4
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sigma = -1.645+1.939*bd-0.0225622*vsand +0.01594*vclay; % Refer to [1]
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else
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sigma = 0.0467+0.2204*bd-0.004111*vsand +0.006614*vclay;% Refer to [2]
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end
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dcwr=dcwinf+((dcw0-dcwinf)./(1+(tpt.*f).^2));
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dcwi=(tpt.*f.*(dcw0-dcwinf))./(1+(tpt.*f).^2)+sigma*(1.0-(bd/sd))./(8.0*atan(1.0)*dc0.*f.*smc);% Refer to [1]
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betar=1.2748-0.00519*vsand-0.00152*vclay;
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betai=1.33797-0.00603*vsand-0.00166*vclay;
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dcsr=(1.0+(bd/sd)*((dcs^alpha)-1.0)+(smc.^betar)*(dcwr^alpha)-smc).^(1/alpha);% Result real part
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dcsi=(smc.^(betai/alpha)).*dcwi;%Result imaginary part
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% dcst=sqrt((dcsr)^2+(dcsi)^2);
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end
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