VLC.zip

%% theta = 70; % semi-angle at half power ml=-log10(2)/log10(cosd(theta)); %Lambertian order of emission P_LED=20; %transmitted optical power by individual LED nLED=60; % number of LED array nLED*nLED P_total=nLED*nLED*P_LED; %Total transmitted power Adet=1e-4; %detector physical area of a PD Ts=1; %gain of an optical filter; ignore if no filter is used index=1.5; %refractive index of a lens at a PD; ignore if no lens is used FOV=70; %FOV of a receiver G_Con=(index^2)/(sind(FOV).^2); %gain of an optical concentrator; ignore if no lens is used %% lx=5; ly=5; lz=3; % room dimension in meter h=2.15; %the distance between source and receiver plane [XT,YT]=meshgrid([-lx/4 lx/4],[-ly/4 ly/4]); % position of LED; it is assumed all LEDs are located at same point for % faster simulation % for one LED simulation located at the central of the room, use XT=0 and YT=0 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Nx=lx*5; Ny=ly*5; % number of grid in the receiver plane x=linspace(-lx/2,lx/2,Nx); y=linspace(-ly/2,ly/2,Ny); [XR,YR]=meshgrid(x,y); D1=sqrt((XR-XT(1,1)).^2+(YR-YT(1,1)).^2+h^2); % distance vector from source 1 cosphi_A1=h./D1; % angle vector receiver_angle=acosd(cosphi_A1); % alternative methods to calculate angle, more accurate if the angle are % negatives % nr=[0 0 1]; % RT=[1.25 1.25]; % transmitter location % for r=1:length(x) % for c=1:length(y) % % angleA12=atan(sqrt((x(r)-1.25).^2+(y(c)-1.25).^2)./h); % costheta(r,c)=cos(angleA12); % end % end % %% % D2=fliplr(D1); % % due to symmetry % D3=flipud(D1); % D4=fliplr(D3); H_A1=(ml+1)*Adet.*cosphi_A1.^(ml+1)./(2*pi.*D1.^2); % channel DC gain for source 1 P_rec_A1=P_total.*H_A1.*Ts.*G_Con; % received power from source 1; P_rec_A1(find(abs(receiver_angle)>FOV))=0; % if the anlge of arrival is greater than FOV, no current is generated at % the photodiode. P_rec_A2=fliplr(P_rec_A1); % received power from source 2, due to symmetry no need separate % calculations P_rec_A3=flipud(P_rec_A1); P_rec_A4=fliplr(P_rec_A3); P_rec_total=P_rec_A1+P_rec_A2+P_rec_A3+P_rec_A4; P_rec_dBm=10*log10(P_rec_total); %% Fig. surfc(x,y,P_rec_dBm); % contour(x,y,P_rec_dBm);hold on % mesh(x,y,P_rec_dBm);