Merge pull request #57 from cjcliffe/optimize-ssb

SSB Optimization
cjcliffe · Feb 22, 2015 · 3ea528f · 3ea528f
2 parents 8a859c6 + 2c33773
commit 3ea528f
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Showing 4 changed files with 14 additions and 45 deletions.
diff --git a/src/AppFrame.cpp b/src/AppFrame.cpp
@@ -370,7 +370,7 @@ void AppFrame::OnIdle(wxIdleEvent& event) {
         }
         if (demodWaterfallCanvas->getDragState() == WaterfallCanvas::WF_DRAG_NONE) {
             long long centerFreq = demod->getFrequency();
-            unsigned int demodBw = (unsigned int) ceil((float) demod->getBandwidth() * 2.5);
+            unsigned int demodBw = (unsigned int) ceil((float) demod->getBandwidth() * 2.25);
 
             if (demod->getDemodulatorType() == DEMOD_TYPE_USB) {
                 demodBw /= 2;
@@ -385,8 +385,8 @@ void AppFrame::OnIdle(wxIdleEvent& event) {
             if (demodBw > wxGetApp().getSampleRate() / 2) {
                 demodBw = wxGetApp().getSampleRate() / 2;
             }
-            if (demodBw < 30000) {
-                demodBw = 30000;
+            if (demodBw < 20000) {
+                demodBw = 20000;
             }
 
             if (centerFreq != demodWaterfallCanvas->getCenterFrequency()) {

diff --git a/src/CubicSDR.cpp b/src/CubicSDR.cpp
@@ -29,7 +29,7 @@ bool CubicSDR::OnInit() {
     sdrThread = new SDRThread(threadCmdQueueSDR);
 
     sdrPostThread = new SDRPostThread();
-    sdrPostThread->setNumVisSamples(16384);
+    sdrPostThread->setNumVisSamples(16384*2);
 
     iqPostDataQueue = new SDRThreadIQDataQueue;
     iqVisualQueue = new DemodulatorThreadInputQueue;

diff --git a/src/demod/DemodulatorThread.cpp b/src/demod/DemodulatorThread.cpp
@@ -73,16 +73,8 @@ void DemodulatorThread::threadMain() {
     nco_crcf stereoShifter = nco_crcf_create(LIQUID_NCO);
     double stereoShiftFrequency = 0;
 
-    // SSB Half-band filter
-    nco_crcf ssbShifterUp = nco_crcf_create(LIQUID_NCO);
-    nco_crcf_set_frequency(ssbShifterUp, (2.0 * M_PI) * 0.25);
-
-    nco_crcf ssbShifterDown = nco_crcf_create(LIQUID_NCO);
-    nco_crcf_set_frequency(ssbShifterDown, (2.0 * M_PI) * 0.25);
-
-    // half band interp / decimate used for side-band elimination
-    resamp2_crcf ssbInterp = resamp2_crcf_create(7, 0.0f, -120.0f);
-    resamp2_crcf ssbDecim = resamp2_crcf_create(7, 0.0f, -120.0f);
+     // half band filter used for side-band elimination
+    resamp2_cccf ssbFilt = resamp2_cccf_create(12,-0.25f,60.0f);
 
     // Automatic IQ gain
     iqAutoGain = agc_crcf_create();
@@ -175,37 +167,15 @@ void DemodulatorThread::threadMain() {
             float p;
             switch (demodulatorType.load()) {
             case DEMOD_TYPE_LSB:
-                for (int i = 0; i < bufSize / 2; i++) { // Reject upper band
-                    nco_crcf_mix_up(ssbShifterUp, inp->data[i * 2], &z[0]);
-                    nco_crcf_step(ssbShifterUp);
-                    nco_crcf_mix_up(ssbShifterUp, inp->data[i * 2 + 1], &z[1]);
-                    nco_crcf_step(ssbShifterUp);
-                    resamp2_crcf_decim_execute(ssbDecim, z, &x);
-                    resamp2_crcf_interp_execute(ssbInterp, x, z);
-
-                    nco_crcf_mix_down(ssbShifterDown, z[0], &x);
-                    nco_crcf_step(ssbShifterDown);
-                    nco_crcf_mix_down(ssbShifterDown, z[1], &y);
-                    nco_crcf_step(ssbShifterDown);
-                    ampmodem_demodulate(demodAM, x, &demodOutputData[i * 2]);
-                    ampmodem_demodulate(demodAM, y, &demodOutputData[i * 2 + 1]);
+                for (int i = 0; i < bufSize; i++) { // Reject upper band
+                     resamp2_cccf_filter_execute(ssbFilt,inp->data[i],&x,&y);
+                     ampmodem_demodulate(demodAM, x, &demodOutputData[i]);
                 }
                 break;
             case DEMOD_TYPE_USB:
-                for (int i = 0; i < bufSize / 2; i++) { // Reject lower band
-                    nco_crcf_mix_down(ssbShifterDown, inp->data[i * 2], &z[0]);
-                    nco_crcf_step(ssbShifterDown);
-                    nco_crcf_mix_down(ssbShifterDown, inp->data[i * 2 + 1], &z[1]);
-                    nco_crcf_step(ssbShifterDown);
-                    resamp2_crcf_decim_execute(ssbDecim, z, &x);
-                    resamp2_crcf_interp_execute(ssbInterp, x, z);
-
-                    nco_crcf_mix_up(ssbShifterUp, z[0], &x);
-                    nco_crcf_step(ssbShifterUp);
-                    nco_crcf_mix_up(ssbShifterUp, z[1], &y);
-                    nco_crcf_step(ssbShifterUp);
-                    ampmodem_demodulate(demodAM, x, &demodOutputData[i * 2]);
-                    ampmodem_demodulate(demodAM, y, &demodOutputData[i * 2 + 1]);
+                for (int i = 0; i < bufSize; i++) { // Reject lower band
+                    resamp2_cccf_filter_execute(ssbFilt,inp->data[i],&x,&y);
+                    ampmodem_demodulate(demodAM, y, &demodOutputData[i]);
                 }
                 break;
             case DEMOD_TYPE_AM:
@@ -441,8 +411,7 @@ void DemodulatorThread::threadMain() {
     firhilbf_destroy(firStereoR2C);
     firhilbf_destroy(firStereoC2R);
     nco_crcf_destroy(stereoShifter);
-    nco_crcf_destroy(ssbShifterUp);
-    nco_crcf_destroy(ssbShifterDown);
+    resamp2_cccf_destroy(ssbFilt);
 
     while (!outputBuffers.empty()) {
         AudioThreadInput *audioDataDel = outputBuffers.front();

diff --git a/src/sdr/SDRPostThread.cpp b/src/sdr/SDRPostThread.cpp
@@ -6,7 +6,7 @@
 #include <deque>
 
 SDRPostThread::SDRPostThread() :
-        iqDataOutQueue(NULL), iqDataInQueue(NULL), iqVisualQueue(NULL), terminated(false), dcFilter(NULL), num_vis_samples(16384) {
+        iqDataOutQueue(NULL), iqDataInQueue(NULL), iqVisualQueue(NULL), terminated(false), dcFilter(NULL), num_vis_samples(16384*2) {
 
     // create a lookup table
     for (unsigned int i = 0; i <= 0xffff; i++) {