MATLAB CODE: 1. CAPACITY WITH AND WITHOUT CSIT FOR 5x10 MIMO SYSTEM clc; clear all; close all; Nt=5; Nr=10;
%---------No. of transmitter antennas %---------No. of receiver antennas
snrdB=0:1:10; %-----------snr values in dB, for which capacity will be computed snr=10.^(snrdB/10); Cut=zeros(1,length(snr)); %---------capacity of a uninformed transmitter i.e., without CSIT Cit=zeros(1,length(snr)); %---------capacity of an informed transmitter i.e., with CSIT Cut_tot=zeros(1,length(snr)); Cit_tot=zeros(1,length(snr)); count=100; for k=1:count H=randn(Nr,Nt)+i*randn(Nr,Nt); %---------channel matrix H [U,S,V]=svd(H); %----------singular value decomposition of H sv=diag(S); %--------------non-zero singular values of H ev=sv.*sv; %--------------eigen values of H r=rank(H); %--------------computing rank of H for i=1:length(snr) %CAPACITY CALCULATION FOR EQUAL POWER ALLOCATION WITHOUR CSIT for j=1:r Cut(i)=Cut(i)+log2(1+((snr(i)/Nt)*ev(j))); end %WATER POURING ALGORITHM FOR CALCULATION OF CAPACITY WITH CSIT p=1; Pi=zeros(1,r); while(Pi(r-p+1)<=0) x=0; for j=1:r-p+1 x=x+(1/ev(j)); end Mu=(Nt/(r-p+1))*(1+(1/snr(i))*x); for j=1:r-p+1 Pi(j)=Mu-(Nt/((snr(i))*ev(j)));
end if Pi(r-p+1)<=0 Pi(r-p+1)=0; end p=p+1; end for j=1:r Cit(i)=Cit(i)+log2(1+((snr(i)/Nt)*Pi(j)*ev(j))); end end Cut_tot=Cut_tot+Cut; Cit_tot=Cit_tot+Cit; end Cut_avg=Cut_tot/count; Cit_avg=Cit_tot/count; for i=1:length(snr) diff(i)=Cit_avg(i)-Cut_avg(i); end %----------------PLOTS----------------------% figure plot(snrdB,Cut_avg,'-*r') hold on plot(snrdB,Cit_avg,'-o') hold on plot(snrdB,diff,'->g') xlabel('SNR in dB') ylabel('Capacity') legend('without CSIT','with CSIT','difference in capacity')
2. CAPACITY WITH AND WITHOUT CSIT FOR 10X5 MIMO SYSTEM clc; clear all; close all; Nt=10; %---------No. of transmitter antennas Nr=5; %---------No. of receiver antennas snrdB=0:1:10; %-----------snr values in dB, for which capacity will be computed snr=10.^(snrdB/10); Cut=zeros(1,length(snr)); %---------capacity of a uninformed transmitter i.e., without CSIT Cit=zeros(1,length(snr)); %---------capacity of an informed transmitter i.e., with CSIT
Cut_tot=zeros(1,length(snr)); Cit_tot=zeros(1,length(snr)); count=100; for k=1:count H=randn(Nr,Nt)+i*randn(Nr,Nt); %---------channel matrix H [U,S,V]=svd(H); %----------singular value decomposition of H sv=diag(S); %--------------non-zero singular values of H ev=sv.*sv; %--------------eigen values of H r=rank(H); %--------------computing rank of H for i=1:length(snr) %CAPACITY CALCULATION FOR EQUAL POWER ALLOCATION WITHOUR CSIT for j=1:r Cut(i)=Cut(i)+log2(1+((snr(i)/Nt)*ev(j))); end %WATER POURING ALGORITHM FOR CALCULATION OF CAPACITY WITH CSIT p=1; Pi=zeros(1,r); while(Pi(r-p+1)<=0) x=0; for j=1:r-p+1 x=x+(1/ev(j)); end Mu=(Nt/(r-p+1))*(1+(1/snr(i))*x); for j=1:r-p+1 Pi(j)=Mu-(Nt/((snr(i))*ev(j))); end if Pi(r-p+1)<=0 Pi(r-p+1)=0; end p=p+1; end for j=1:r Cit(i)=Cit(i)+log2(1+((snr(i)/Nt)*Pi(j)*ev(j))); end end Cut_tot=Cut_tot+Cut; Cit_tot=Cit_tot+Cit; end Cut_avg=Cut_tot/count; Cit_avg=Cit_tot/count; for i=1:length(snr) diff(i)=Cit_avg(i)-Cut_avg(i);
end %----------------PLOTS----------------------% figure plot(snrdB,Cut_avg,'-*r') hold on plot(snrdB,Cit_avg,'-o') hold on plot(snrdB,diff,'->g') xlabel('SNR in dB') ylabel('Capacity') legend('without CSIT','with CSIT','difference in capacity')
PLOTS: 1. Nt
2. Nt>Nr
EC6325 MIMO COMMUNICATION SYSTEMS ASSIGNMENT
SUBMITTED BY: NAMITHA R S2 TELECOMMUNICATION M110253EC
OBSERVATION: 1.Nt>Nr diff =
3.3068 3.4490 3.5999 3.7543 4.3157 4.4270 4.5244 4.6082
3.9072
4.0539
4.1909
0.0251
0.0169
0.0112
2.Nt
0.1053 0.0755 0.0532 0.0368 0.0074 0.0048 0.0031 0.0020
