git-svn-id: http://svn.eurecom.fr/openair4G/trunk@5244 818b1a75-f10b-46b9-bf7c-635c3b92a50f

targets/PROJECTS/CORRIDOR/emos_read_v2_1.m

+close all
+clear all
+
+enable_plots=1; %eanbles figures
+
+%% preload and init data
+addpath('../../../openair1/PHY/LTE_REFSIG');
+primary_synch; %loads the primary sync signal
+pss_t = upsample(primary_synch0_time,4);
+
+%load('E:\EMOS\corridor\ofdm_pilots_sync_2048_v7.mat');
+load('ofdm_pilots_sync_30MHz.mat');
+
+ofdm_symbol_length = num_carriers + prefix_length;
+frame_length = ofdm_symbol_length*num_symbols_frame;
+useful_carriers = num_carriers-num_zeros-1;
+
+%filename = 'E:\EMOS\corridor\lab tests\eNB_data_20140321_184441.EMOS';
+%filename = 'E:\EMOS\corridor\711MHz\eNB_data_20140324_113931.EMOS';
+filename = 'E:\EMOS\corridor\trials1\eNB_data_20140331_UHF_run1.EMOS';
+%filename = 'D:\trials1 day 1 771.5MHz\eNB_data_20140327_153151.EMOS';
+destdir = 'E:\EMOS\corridor\trials1 day1\711.5MHz';
+
+samples_slot = 7680/2;
+slots_per_frame = 20;
+nframes = 100;
+nant_rx=3;
+nant_tx=4;
+
+d = dir(filename);
+nblocks = floor(d.bytes/(samples_slot*slots_per_frame*nframes*nant_rx*4));
+PDP_total = zeros(nblocks*nframes,useful_carriers/4,nant_tx,nant_rx);
+
+%% main loop
+fid = fopen(filename,'r');
+
+vStorage = [];  %%
+
+
+block = 1; %
+flag1 = 1;
+start=2;
+
+threshold = 3e+4 ; % maybe should change that !!!!
+
+%  fseek(fid,samples_slot*slots_per_frame*nframes*nant*102*2,'bof');
+%  %advance 102 sec
+
+while ~feof(fid)
+    fprintf(1,'Processing block %d of %d',block,nblocks);
+    
+    [v,c]=fread(fid, samples_slot*slots_per_frame*nframes*nant_rx*2, 'int16',0,'ieee-le');
+    if (c==0)
+        break
+    end
+    v1 = double(v(1:2:end))+1j*double(v(2:2:end));
+    
+    nframes = 100;
+    
+    v2 = zeros(samples_slot*slots_per_frame*nframes,nant_rx);
+    for slot=1:slots_per_frame*nframes
+        for a=1:nant_rx
+            v2((slot-1)*samples_slot+1:slot*samples_slot,a) = ...
+                v1((slot-1)*samples_slot*nant_rx+(a-1)*samples_slot+1:...
+                   (slot-1)*samples_slot*nant_rx+ a   *samples_slot,1);
+        end
+    end
+    
+    
+    v2 = [vStorage; v2] ;%%
+    if size(v2,1) > frame_length*nframes ;
+        nframes = floor(size(v2,1) / frame_length) ;
+        vStorage = v2(frame_length*nframes+1:end,:) ;
+        v2(frame_length*nframes + 1 : end,:) = [] ;
+        start = 1 ;
+    end
+    
+    if enable_plots>=2
+        figure(1)
+        plot(20*log10(abs(fftshift(fft(v2)))))
+    end
+    
+    %% frame start detection
+    if flag1==1
+        [corr,lag] = xcorr(v2(:,1),pss_t);
+        %[m,idx]=max(abs(corr));
+        %[m,idx]=peaksfinder(corr,frame_length);
+        
+        tmp   = corr(nframes*slots_per_frame*samples_slot:end);
+        tmp2  = reshape(tmp,slots_per_frame*samples_slot,nframes);
+        [m,idx] = max(abs(tmp2),[],1);
+       
+%         meanCorr = mean(abs(tmp2));
+%         [mm,where] = max(m./meanCorr)
+        
+        idx(m < threshold) = [];
+        if size(idx,2) <= 1
+            flag1 = 1 ;
+            flag2 = 0 ;
+            
+            vStorage = [];
+%         elseif size(idx,2) == nframes
+%             
+%             flag1 = 0;
+%             flag2 = 1;
+        else
+            flag1 = 0 ;
+            flag2 = 1 ;
+        end
+        
+        frame_offset = round(median(idx)) - prefix_length;
+        
+
+        if enable_plots>=2
+            figure(2);
+            hold off
+            plot(lag,abs(corr));
+            hold on
+            plot(frame_offset,m(1),'ro')
+        end
+    else
+        frame_offset = 0; %%%%% line 93 florian's 
+    end
+    
+    if flag2 == 1
+        for i=start:nframes;
+            fprintf(1,'.');
+            frame_start = (slots_per_frame*samples_slot)*(i-1)+frame_offset+1;
+            %frame_start = lag(idx(i))-prefix_length;
+            % frame_start = lag(i) - prefix_length;
+            
+            if i<nframes
+                %% ofdm receiver
+                received_f = OFDM_RX(v2(frame_start:frame_start+frame_length,:),num_carriers,useful_carriers,prefix_length,num_symbols_frame);
+            else
+                vStorage = [v2(frame_start:end,:) ; vStorage];  %%
+            end
+        %% MIMO channel estimation
+        H = zeros(num_symbols_frame/2,useful_carriers/4,nant_tx,nant_rx);
+        for itx=1:nant_tx
+            % f_start and t_start indicate the start of the pilots in time
+            % and frequency according to the specifications (see .doc file). 
+            % t_start has to be >=2, since the first symbol is the PSS.
+            f_start = mod(itx-1,2)*2+1;
+            t_start = floor((itx-1)/2)+1;
+            for irx=1:nant_rx
+                H(:,:,itx,irx)=conj(squeeze(f3(itx,t_start:2:end,f_start:4:end))).*received_f(t_start:2:end,f_start:4:end,irx);
+            end
+        end
+        Ht = ifft(H,[],2);
+        PDP = mean(abs(Ht).^2,1);
+        PDP_all = squeeze(mean(mean(PDP,3),4));
+        PDP_total((block-1)*nframes+i+1,:,:,:) = PDP;
+        
+        % adjust frame offset base on channel estimate to compensate for
+        % timing drift. We try to keep the peak of the impulse response at
+        % sample prefix_length/8.
+        [m,idx] = max(fft(ifft(PDP_all),num_carriers));
+        offset = idx - prefix_length/8;
+        if offset > prefix_length
+            offset = offset - num_carriers;
+        end
+        if abs(offset) > 5
+            frame_offset = frame_offset + round(offset/4);
+        end
+        
+        if enable_plots>=1
+            figure(3)
+            for itx=1:nant_tx
+                for irx=1:nant_rx
+                    subplot(nant_tx,nant_rx,(itx-1)*nant_rx + irx);
+                    surf(20*log10(abs(Ht(:,:,itx,irx))))
+                    %xlabel('time [OFDM symbol]')
+                    %ylabel('delay time [samples]')
+                    %zlabel('power [dB]')
+                    shading interp
+                end
+            end
+            figure(4)
+            for itx=1:nant_tx
+                for irx=1:nant_rx
+                    subplot(nant_tx,nant_rx,(itx-1)*nant_rx + irx);
+                    plot(10*log10(PDP(:,:,itx,irx)))
+                    ylim([50 80])
+                    xlim([0 75])
+                    %xlabel('delay time [samples]')
+                    %ylabel('power [dB]')
+                end
+            end
+            drawnow
+        end
+        end
+    end
+    fprintf(1,'\n');
+    block = block+1;
+end
+
+fclose(fid);
+
+%% save processed data
+[path,name,ext]=fileparts(filename);
+save([destdir filesep name '.mat'],'PDP_total');
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