# Underwater Acoustic channel simulation issue.Figure 3 Result of paper in comment are not matching. I don't know wy the values are comming half in dB [duplicate]

clc
clear all;

%----------Underwater Acoustic Communication Channels: Propagation Models and
%----------Statistical Characterization-------------------------------%
%------Milica Stojanovic, Northeastern University---------------
%------James Preisig, Woods Hole Oceanographic Institution--------------%

s=0.5; %shipping
w=0;    %wind in m/s
%Attenuation_factor1=[];
%Attenuaton_Noise1=[];
SNR_Plot=[];
distance=5; %km
P_t= 2%watts
for f=0:0.1:20

af4=((0.11*(f^2)/(1+f^2))+(44*(f^2)/(4100+f^2))+((2.75*10^(-4)*(f^2)))+0.003);
aF=power(10,af4*0.1);
AF=(distance^k)*(aF^distance);

Turbulence=17-(30*log10(f));
Noise_Turbulence=  power(10,(Turbulence*0.1));

Shipping=40+(20*(s-0.5))+(26*log10(f))-(60*log10((f)+0.03));
Noise_Shipping= power(10,(Shipping*0.1));

Wind=50+(7.5*(power(w,0.5)))+(20*log10(f))-(40*log10((f)+0.4));
Noise_Wind=power(10,(Wind*0.1));

Thermal=-15+(20*log10(f));
Noise_Thermal= power(10,(Thermal*0.1));

Noise=Noise_Turbulence+Noise_Shipping+Noise_Wind+Noise_Thermal;

SNR=1/(AF*Noise);
%SNR=SNR*2;

SNR1=10*log10(SNR);
Intensity = (P_t/4*pi*1*(distance*1000));
SL=10*log10(Intensity/(0.67*(10^(-18))));
% SNR1=-SL-SNR1;
SNR_Plot=[SNR_Plot SNR1];

end

figure;
f=0:0.1:20;
plot(f,SNR_Plot,'m');
grid on;
xlabel('frequency(KHz)')
ylabel('1/AN (db)')

$$$$
`
• @Haskim Khan To be honest, I don’t see too many people downloading the paper and comparing plots and then explaining why you do or don’t get some result. It’s a bit of work. Looking at your code, there are very few places where the wind=0. Sea State zero is not a realistic scenario. A calm ocean is at least SS 1/2. – user28715 Oct 16 '19 at 19:06
• i guess i am missing the units trick here. I am computing all the units and then i will share the result what was missing. I hope my attempt is right. – Hashim Khan Oct 17 '19 at 16:22