Added PSS mex test

lte/phy/lib/sync/test/CMakeLists.txt

@@ -29,6 +29,8 @@ IF(${CUHD_FIND} GREATER -1)
   TARGET_LINK_LIBRARIES(pss_usrp lte_phy cuhd)
 ENDIF(${CUHD_FIND} GREATER -1)
 
+BuildMex(MEXNAME pss SOURCES pss_mex.c LIBRARIES lte_phy liblte_mex)
+
 ########################################################################
 # SYNC TEST  
 ########################################################################

lte/phy/lib/sync/test/pss_mex.c

@@ -0,0 +1,87 @@
+/* 
+ * Copyright (c) 2012, Ismael Gomez-Miguelez <ismael.gomez@tsc.upc.edu>.
+ * This file is part of ALOE++ (http://flexnets.upc.edu/)
+ * 
+ * ALOE++ is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * ALOE++ is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with ALOE++.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+#include "liblte/phy/phy.h"
+#include "liblte/mex/mexutils.h"
+
+/** MEX function to be called from MATLAB to test the channel estimator 
+ */
+
+#define ENBCFG  prhs[0]
+#define INPUT   prhs[1]
+#define NOF_INPUTS 2
+
+
+void help()
+{
+  mexErrMsgTxt
+    ("[offset,corr] = liblte_pss(enbConfig, inputSignal)\n\n");
+}
+
+/* the gateway function */
+void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
+{
+
+  int i;
+  lte_cell_t cell; 
+  pss_synch_t pss; 
+  cf_t *input_symbols;
+  int frame_len; 
+  
+  if (nrhs != NOF_INPUTS) {
+    help();
+    return;
+  }
+    
+  if (mexutils_read_cell(ENBCFG, &cell)) {
+    help();
+    return;
+  }
+  
+  /** Allocate input buffers */
+  frame_len = mexutils_read_cf(INPUT, &input_symbols);
+  if (frame_len < 0) {
+    mexErrMsgTxt("Error reading input symbols\n");
+    return;
+  }
+  
+  if (pss_synch_init_fft(&pss, frame_len, lte_symbol_sz(cell.nof_prb))) {
+    fprintf(stderr, "Error initiating PSS\n");
+    exit(-1);
+  }
+  if (pss_synch_set_N_id_2(&pss, cell.id%2)) {
+    fprintf(stderr, "Error setting N_id_2=%d\n",cell.id%2);
+    exit(-1);
+  }
+      
+  int peak_idx = pss_synch_find_pss(&pss, input_symbols, NULL);
+  
+  if (nlhs >= 1) { 
+    plhs[0] = mxCreateLogicalScalar(peak_idx);
+  }
+  if (nlhs >= 2) {
+    mexutils_write_cf(pss.conv_output, &plhs[1], frame_len, 1);  
+  }
+    
+  pss_synch_free(&pss);
+  free(input_symbols);
+
+  return;
+}
+

matlab/tests/sync_test.m

@@ -1,32 +1,44 @@
 enb = lteTestModel('1.1','5MHz');
 Ntrials = 1; 
-SNR_values =-10;%linspace(-18,-10,8);
+SNR_values =-20;%linspace(-18,-10,8);
 
 tx_offset = randi(50,Ntrials,1);
-tx_offset = 50;
 diff=zeros(size(SNR_values));
+diff_lt=zeros(size(SNR_values));
 
 tx_signal = lteTestModelTool(enb); 
 tx_power = mean(tx_signal.*conj(tx_signal));
 
+corrcfg.PSS='On';
+corrcfg.SSS='On';
+corrcfg.CellRS='Off';
+
+addpath('../../debug/lte/phy/lib/sync/test')
+
 for snr_idx=1:length(SNR_values)
     SNRdB = SNR_values(snr_idx);
     rx_offset = zeros(size(tx_offset));
+    rx_offset_lt = zeros(size(tx_offset));
     for i=1:Ntrials
         SNR = 10^(SNRdB/10);    % Linear SNR  
         tx = [zeros(tx_offset(i),1); tx_signal];
         N0  = tx_power/(sqrt(2.0)*SNR);
         noise = N0*complex(randn(size(tx)), randn(size(tx)));  % Generate noise
         rx=noise+tx;
-        [rx_offset(i),corr] = lteDLFrameOffset(enb,rx);
+        [rx_offset(i),corr] = lteDLFrameOffset(enb,rx,corrcfg);
+        [rx_offset_lt(i),corr_lt] = liblte_pss(enb,rx);
     end
     diff(snr_idx)=sum(abs(rx_offset-tx_offset));
+    diff_lt(snr_idx)=sum(abs(rx_offset_lt-tx_offset));
     disp(SNRdB)
 end
 
 if (Ntrials == 1)
-    plot(corr)
+    len=1:length(corr)-rx_offset(i)-3840;
+    len2=rx_offset(i)+1+3840:length(corr);
+    plot(len,corr(len)/max(corr(len)),...
+        len,abs(corr_lt(len2))/max(abs(corr_lt(len2))));
 else
-    plot(SNR_values,diff);
+    plot(SNR_values,diff,SNR_values,diff_lt);
 end