# % Author: Mirsad Cirkic, Florian Kaltenberger # % Organisation: Eurecom (and Linkoping University) # % E-mail: mirsad.cirkic@liu.se if(paramsinitialized && ~LSBSWITCH_FLAG) disp(["\n\n------------\nThis code is, so far, only written for single runs. Multiple " ... "runs will overwrite the previous measurement data, i.e., the " ... "data structures are not defined for multiple runs. You will need to " ... "add code in order to save the intermediate measurements and the " ... "corresponding timestamps.\n------------"]) N=76800; M=4; indA=find(active_rfA==1); indB=find(active_rfB==1); Nanta=length(indA); Nantb=length(indB); if(Nanta!=1) error("Node A can only have one antenna active\n"); endif Niter=1; if(Niter!=1) error("We should only use one get_frame at each run.\n"); endif Nmeas = 100; # %% ------- Prepare the signals for A2B ---------- %% signalA2B=zeros(N,4); signalB2A=zeros(N,4); ia=1; ib=1; Db2a_T=[]; 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) signalB2A(:,i)=repmat(1+1j,76800,1); %make sure LSB is 1 (switch=rx) if(length(indA)> ia) ia=ia+1; endif endif % if(indB(ib)==i) % % This part could be improved by creating fully orthogonal sequences % [tmpd, tmps]=genrandpskseq(N,M,amp); % signalB2A(:,i)=tmps*2; % signalA2B(:,i)=repmat(1+1j,76800,1); % Db2a_T=[Db2a_T tmpd]; % if(length(indB)> ib) ib=ib+1; endif % endif endfor #%%------------Prepare the signals for B2A---------------%% for i=1:4 if(indB(ib)==i) [tmpd, tmps]=genrandpskseq(N,M,amp); signalB2A(:,i)=tmps*2; %make sure LSB is 0 (switch=tx) signalA2B(:,i)=repmat(1+1j,76800,1); %make sure LSB is 1 (switch=rx) Db2a_T=[Db2a_T tmpd]; if(length(indB)> ib) ib=ib+1; endif endif endfor if (!chanest_full) signalB2A(1:38400,3)=0; signalB2A(38401:end,2)=0; Db2a_T(1:60,302:end) = 0; Db2a_T(61:end,1:301) = 0; end Da2b_R=zeros(Niter*120,Nantb*301,Nmeas); Db2a_R=zeros(Niter*120,Nanta*301,Nmeas); for meas=1:Nmeas # %% ------- Node A to B transmission ------- %% 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); #%%----------Node B to A transmission---------%% oarf_send_frame(card,signalB2A,n_bit); %keyboard sleep(0.01); receivedB2A=oarf_get_frame(card); %oarf_stop(card); %not good, since it does a reset # %% ------- 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((Niter-1)*120+i+1,:,meas)=vec(fblock); endfor HA2B=repmat(conj(Da2b_T),Niter,Nantb).*Da2b_R(:,:,meas); phasesA2B=unwrap(angle(HA2B)); if(mean(var(phasesA2B))>0.5) disp("The phases of your estimates from A to B are a bit high (larger than 0.5 rad.), something is wrong."); endif chanestsA2B(:,:,meas)=reshape(diag(repmat(Da2b_T,Niter,Nantb)'*Da2b_R(:,:,meas))/size(Da2b_T,1),301,Nantb); #fchanestsA2B=zeros(512,Nantb); #for i=1:Nantb # fchanestsA2B(:,i)=[0; chanestsA2B([1:150],i,meas); zeros(210,1); chanestsA2B(151:301,i,meas)]; #endfor fchanestsA2B(:,:,meas)=[zeros(1,Nantb); chanestsA2B([1:150],:,meas); zeros(210,Nantb); chanestsA2B(151:301,:,meas)]; tchanestsA2B(:,:,meas)=ifft(fchanestsA2B(:,:,meas)); %% ------- Do the B to A channel estimation ------- %% for i=0:119; ifblock=receivedB2A(i*640+[1:640],indA); ifblock(1:128,:)=[]; fblock=fft(ifblock); fblock(1,:)=[]; fblock(151:360,:)=[]; Db2a_R((Niter-1)*120+i+1,:,meas)=fblock.'; endfor HB2A=conj(repmat(Db2a_T,Niter,1)).*repmat(Db2a_R(:,:,meas),1,Nantb); phasesB2A=unwrap(angle(HB2A)); if(mean(var(phasesB2A))>0.5) disp("The phases of your estimates from B to A are a bit high (larger than 0.5 rad.), something is wrong."); endif if (chanest_full) chanestsB2A(:,:,meas)=zeros(301,Nantb); inds=repmat([1:Nantb]',1,301); for ci=1:301; data=Db2a_T(:,ci+[0:Nantb-1]*301); rec=Db2a_R(:,ci,meas); chanestsB2A(ci,:,meas)=(inv(data'*data)*data'*rec).'; endfor else chanestsB2A(:,:,meas)=reshape(diag(repmat(Db2a_T,Niter,1)'*repmat(Db2a_R(:,:,meas),1,Nantb)/(Niter*60)),301,Nantb); end #fchanestsB2A=zeros(512,Nantb); #for i=1:Nantb # fchanestsB2A(:,i)=[0; chanestsB2A([1:150],i); zeros(210,1); chanestsB2A(151:301,i)]; #endfor fchanestsB2A(:,:,meas) = [zeros(1,Nantb); chanestsB2A([1:150],:,meas); zeros(210,Nantb); chanestsB2A(151:301,:,meas)]; tchanestsB2A(:,:,meas)=ifft(fchanestsB2A(:,:,meas)); end %% -- Some plotting code -- %% (you can uncomment what you see fit) received = receivedB2A; phases = phasesB2A; tchanests = [tchanestsA2B(:,:,end), tchanestsB2A(:,:,end)]; fchanests = [fchanestsA2B(:,:,end), fchanestsB2A(:,:,end)]; clf figure(1) for i=1:4 subplot(220+i);plot(20*log10(abs(fftshift(fft(received(:,i)))))); endfor figure(2) t=[0:512-1]/512*1e-2; plot(t,20*log10(abs(tchanests))) xlabel('time') ylabel('|h|') legend('A->B1','A->B2','B1->A','B2->A'); figure(4) plot(20*log10(abs(fchanests))); ylim([40 100]) xlabel('freq') ylabel('|h|') legend('A->B1','A->B2','B1->A','B2->A'); if (0) figure(3) wndw = 50; for i=1:5:Nantb*301 %# sliding window size phamean = filter(ones(wndw,1)/wndw, 1, phases(:,i)); %# moving average plot(phamean(wndw:end),'LineWidth',2); title(['subcarrier ' num2str(i)]); xlabel('time') ylabel('phase') ylim([-pi pi]) drawnow; pause(0.1) endfor phavar=var(phases); plotphavar=[]; for i=0:Nantb-1 plotphavar=[plotphavar; phavar([1:301]+i*301)]; endfor plot([1:150 362:512],plotphavar,'o'); %ylim([0 pi]) xlabel('subcarrier') ylabel('phase variance') end else if(LSBSWITCH_FLAG) error("You have to unset the LSB switch flag (LSBSWITCH_FLAG) in initparams.m.\n") else error("You have to run init.params.m first!") endif endif