CAPACITY IN CDMA SCENARIO 2
%CAPACITY IN CDMA SCENARIO 2
%Ring 0 and Ring 1 : LTE
%Ring 2 : D2D
a=0.1;%percentage of BW for D2D
B=10^7;%BW = 10Mhz
R=1000;%radius of cell
M=11.875;%number of D2D cell
d=3.18*10^(-5):0.00002:15.9*10^(-5);%user density (100 to 500)
r=(2/15)*3^(1/2)*R;
S_d2d=(3/2)*3^(1/2)*r^2;
N_cell=d*7*S_d2d;
N_d2d=d*S_d2d;
S_total=(453/16)*3^(1/2)*r^2;
N0=d*S_total;
Q=3;% reuse factor
C_cell = B*log2(1+1./(N0-1));
C_cell_d2d_nonOL = (1-a)*B*log2(1+1./(N_cell-1))+M*a*B*log2(1+1./(N_d2d-1));
C_cell_d2d_nonOL_half = (1-a)*B*log2(1+1./(N_cell+M*N_d2d/2-
1))+M*a*B*log2(1+1./(N_d2d/2-1));
C_cell_d2d_shared_Q = B*log2(1+1./(N_cell-1))+(M/Q)*B*log2(1+1./(N_d2d-1));
C_reference = (1-a)*B*log2(1+1./(17.875*N_cell-1))+a*B*log2(1+1./(N_d2d-1));
plot(d,C_cell,'-o',d,C_cell_d2d_nonOL,'-+',d,C_cell_d2d_nonOL_half,'-
*',d,C_cell_d2d_shared_Q,'-s',d,C_reference,'-^');
legend('CDMA only','CDMA with d2d nonOL','CDMA with d2d nonOL 1/2 Backward
comp','CDMA with d2d shared with Q=3','existing');
xlim([3.18*10^(-5) 15.9*10^(-5)]);
xlabel('User density(number per square meters)');
ylabel('Capacity(bps)');
grid;
