adding emos_read_v2.m

git-svn-id: http://svn.eurecom.fr/openair4G/trunk@5225 818b1a75-f10b-46b9-bf7c-635c3b92a50f

targets/PROJECTS/CORRIDOR/emos_read_v2.m

@@ -0,0 +1,128 @@
+close all
+clear all
+
+enable_plots=2; %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 = 'D:\711MHz\eNB_data_20140324_113931.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=3;
+
+d = dir(filename);
+nblocks = floor(d.bytes/(samples_slot*slots_per_frame*nframes*nant*4));
+PDP_total = zeros(nblocks*nframes,useful_carriers/4);
+
+%% main loop
+fid = fopen(filename,'r');
+block = 1;
+while ~feof(fid)
+    fprintf(1,'Processing block %d of %d',block,nblocks);
+    
+    [v,c]=fread(fid, samples_slot*slots_per_frame*nframes*nant*2, 'int16',0,'ieee-le');
+    if (c==0)
+        break
+    end
+    v1 = double(v(1:2:end))+1j*double(v(2:2:end));
+    
+    v2 = zeros(samples_slot*slots_per_frame*nframes,nant);
+    for slot=1:slots_per_frame*nframes
+        for a=1:nant
+            v2((slot-1)*samples_slot+1:slot*samples_slot,a) = ...
+                v1((slot-1)*samples_slot*nant+(a-1)*samples_slot+1:...
+                   (slot-1)*samples_slot*nant+ a   *samples_slot,1);
+        end
+    end
+
+    if enable_plots>=2
+        figure(1)
+        plot(20*log10(abs(fftshift(fft(v2)))))
+    end
+    
+    %% frame start detection
+    if block==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);
+        frame_offset = round(mean(idx)) - prefix_length;
+
+        if enable_plots>=2
+            figure(2);
+            hold off
+            plot(lag,abs(corr));
+            hold on
+            plot(frame_offset,m(1),'ro')
+        end
+    
+        start=2;
+    else
+        start=1;
+    end
+    
+    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;
+        
+        %% ofdm receiver
+        received_f = OFDM_RX(v2(frame_start:frame_start+frame_length,:),num_carriers,useful_carriers,prefix_length,num_symbols_frame);
+        
+        %% channel estimation
+        H=conj(squeeze(f3(1,3:2:end,1:4:end))).*received_f(3:2:end,1:4:end,1);
+        Ht = ifft(H,[],2);
+        PDP = mean(abs(Ht).^2,1);
+        PDP_total((block-1)*nframes+i+1,:) = PDP;
+        
+        [m,idx] = max(fft(ifft(PDP),num_carriers));
+        offset = idx - prefix_length/8;
+        if offset > prefix_length
+            offset = offset - num_carriers;
+        end
+        if abs(offset) > 5
+            frame_offset = frame_offset + offset;
+        end
+        
+        if enable_plots>=1
+            figure(3)
+            surf(20*log10(abs(Ht)))
+            xlabel('time [OFDM symbol]')
+            ylabel('delay time [samples]')
+            zlabel('power [dB]')
+            shading interp
+            figure(4)
+            plot(10*log10(PDP))
+            xlabel('delay time [samples]')
+            ylabel('power [dB]')
+        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');