Commit f60f4109 authored by Florian Kaltenberger's avatar Florian Kaltenberger
Browse files

adding files to test reciprocity beamforming

git-svn-id: http://svn.eurecom.fr/openair4G/trunk@4179 818b1a75-f10b-46b9-bf7c-635c3b92a50f
parent 5f9b167a
function [F, HA]=alterproj(CHB2A,CHA2B, s, N, Nl, Nt)
for l=1:Nl
YA(:,((l-1)*Nt+1):(l*Nt))=squeeze(CHB2A{l}(s,:,:));
YB(:,((l-1)*Nt+1):(l*Nt))=squeeze(CHA2B{l}(s,:,:));
end
HA=zeros(N,Nl);
for l=1:Nl
for t=1:Nt
HA(:,l)=HA(:,l)+YA(:,t+(l-1)*Nt);
end
HA(:,l)=HA(:,l)/Nt;
end
GA=kron(HA,ones(1,Nt));
F=YB*GA'*inv(GA*GA');
oldobj=1e14;
newobj=norm(YB-F*GA)^2+norm(YA-GA)^2;
while(oldobj-newobj>1e-10)
oldobj=newobj;
FI=repmat([F; eye(N)],Nt,1);
YBA=reshape([YB; YA],2*N*Nt,Nl);
FIFI=FI'*FI;
if(cond(FIFI)>30)
warning(['The cond. number in HA est is ' num2str(cond(FIFI))])
end
HA=inv(FIFI)*FI'*YBA;
GA=kron(HA,ones(1,Nt));
GAGA=GA*GA';
if(cond(GAGA)>30)
warning(['The cond. number in F est. is ' num2str(cond(GAGA))])
end
F=YB*GA'*inv(GAGA);
newobj=norm(YB-F*GA)^2+norm(YA-GA)^2;
end
end
initparams;
N = 100; % N is number ofr time-measurements
Nt = 3; % Nt is the number of antennas at node B
N_loc = 3; %check
CHA2B = {}; %this should be a cell array
CHB2A = {}; %this should be a cell array
% run measurements for all location
for loc = 1:N_loc
run_measwoduplex;
% alternatively load the measurements from file for testing
% now you should have chanestA2B, fchanestA2B, tchanestA2B, chanestB2A,
% fchanestB2A, tchanestB2A
CHA2B{loc} = chanestA2B; %to check
CHA2B{loc} = chanestA2B; %to check
disp('Please move the antenna to another location and press key when finished')
pause
end
%% calculate full F matrix
for s=1:301
[F, HA]=alterproj(CHB2A,CHA2B, s, N, N_loc, Nt);
Fs{s}=F;
HAs{s}=HA;
end
%% plot F
figure(1)
clf
hold on;
for s=1:size(Fs,3);
F=Fs(:,:,s);
plot(diag(F),'bo')
plot(diag(F,1),'r+')
plot(diag(F,2),'gx')
end
%axis([-1 1 -1 1])
hold off;
% do some beamforming
signalA2B=zeros(N,4);
signalB2A=zeros(N,4);
signalB2A_prec=zeros(N,4);
%%----------Node A to B transmission---------%%
for i=1:4
if(indA(ia)==i)
[Da2b_T, tmps]=genrandpskseq(N,M,amp);
signalA2B(:,i)=tmps*2; %make sure LSB is 0 (switch=tx)
else
signalA2B(:,i)=repmat(1+1j,76800,1); %make sure LSB is 1 (switch=rx)
end
end
oarf_send_frame(card,signalA2B,n_bit);
%keyboard
sleep(0.01);
receivedA2B=oarf_get_frame(card);
%oarf_stop(card); %not good, since it does a reset
sleep(0.01);
%% ------- Do the A to B channel estimation ------- %%
for i=0:119;
ifblock=receivedA2B(i*640+[1:640],indB);
ifblock(1:128,:)=[];
fblock=fft(ifblock);
fblock(1,:)=[];
fblock(151:360,:)=[];
Da2b_R=vec(fblock);
end
chanestsA2B=reshape(diag(repmat(Da2b_T,Nantb)'*Da2b_R)/size(Da2b_T,1),301,Nantb);
%fchanestsA2B(:,:,meas)=[zeros(1,Nantb); chanestsA2B([1:150],:,meas); zeros(210,Nantb); chanestsA2B(151:301,:,meas)];
%tchanestsA2B(:,:,meas)=ifft(fchanestsA2B(:,:,meas));
%% calculate beamformer based on chanestA2B
for i=1:301
YA=squeeze(chanestA2B(i,:,:));
F=Fs(:,:,i);
Bd(:,i) = conj(F*YA);
end
%% generate normal and beamformed signals
[seqf, tmps]=genrandpskseq(N,M,amp);
for i=1:size(seqf,1)
% precoding
for j=1:size(seqf,2)
symbol_prec(:,j)=Bd(:,j)*seqf(i,j);
end
% insert zero subcarriers
symbol_prec=cat(2,zeros(3,1),symbol_prec(:,1:150),zeros(3,210),symbol_prec(:,151:301));
% ofdm modulation
symbol_prec_t=ifft(symbol_prec,512,2);
% Adding cycl. prefix making the block of 640 elements
symbol_prec_cp = cat(2,symbol_prec_t(:,end-127:end), symbol_prec_t);
tmps_prec(:,[1:640]+i*640)=floor(amp*symbol_prec_cp);
end
for i=1:4
if(indB(ib)==i)
signalB2A(:,i)=tmps*2; %make sure LSB is 0 (switch=tx)
signalB2A_prec(:,i)=tmps_prec(i,:)*2; %make sure LSB is 0 (switch=tx)
else
signalB2A(:,i)=repmat(1+1j,76800,1); %make sure LSB is 1 (switch=rx)
signalB2A_prec(:,i)=repmat(1+1j,76800,1); %make sure LSB is 1 (switch=rx)
end
end
%% send normal signal
oarf_send_frame(card,signalB2A,n_bit);
%keyboard
sleep(0.01);
receivedB2A=oarf_get_frame(card);
sleep(0.01);
% measure SNR
%% send beamformed DL signal
oarf_send_frame(card,signalB2A_prec,n_bit);
%keyboard
sleep(0.01);
receivedB2A=oarf_get_frame(card);
sleep(0.01);
% measure SNR
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