% plot of molecular resonance of H20 for frequencies above 10GHz

f=10:.25:100;
P=1013;
T=300;
pv=7.5;
gam1=(P/1013)*((300/T)^.626)*(1+.018*pv*T/P);
G=1./((494.4-f.^2).^2+4*f.^2*gam1^2);
k=2*pv*(300/T)^1.5*gam1*f.^2.*((300/T).*exp(-644/T).*G+1.2E-6);
figure;
semilogy(f,k/2,'k')
xlabel('Frequency (GHz)')
ylabel('Specific Attenuation (dB/km)')
axis([10 100 .0001 10])