Frequency shifter using analytic signal for ST Nucleo F401RE.

Dependencies:   UITDSP_ADDA mbed

Revision:
0:4269710caf90
Child:
2:ba46d7cbb09e
diff -r 000000000000 -r 4269710caf90 main.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Oct 23 00:48:13 2014 +0000
@@ -0,0 +1,48 @@
+//--------------------------------------------------------------
+// Frequency shifter using analytic signal
+//      Frequency is shifted toward 100 Hz higher
+// 2014/10/23, Copyright (c) 2014 MIKAMI, Naoki
+//--------------------------------------------------------------
+
+#include "mbed.h"
+
+#include "ADC_Base.hpp"             // for ADC not using interrupt
+#include "DAC_MCP4922.hpp"          // for DAC MCP4922
+#include "ScfClockTim3.hpp"         // for clock supplied to SCF
+
+#include "HilbertTransform.hpp"     // Hilbert transform filter
+#include "coefsHilbert114.hpp"      // Coeffisients of Hilbert transform filter
+#include "DC_Cut_Coefficients.hpp"  // Coeffisients of DC-cut filter
+#include "Biquad.hpp"               // For DC-cut filter
+#include "TwoPhaseGenerator.hpp"    // Two-phase generator
+
+using namespace Mikami;
+
+const int FS_ = 12000;  // 12 kHz
+ADC_Base adc_(A0, FS_);
+DAC_MCP4922 myDac_;
+
+Hilbert<ORDER_> ht_(hm_);   // Hilbert transform filter
+Biquad DcCut_(c1_);         // DC cut filter
+TwoPhaseGenerator cosSin_(100, (float)FS_); // 100 Hz
+
+int main()
+{
+    ScfClockTim3(500000);       // cutoff frequency: 5 kHz
+
+    while (true)
+    {
+        float xn = adc_.Read();         // Read from A0
+        //-----------------------------------------------
+
+        xn = DcCut_.Execute(g0_*xn);    // DC cut filter
+        float yIn, yQn;
+        ht_.Execute(xn, yIn, yQn);      // Hilbert transform filter
+        float cos, sin;
+        cosSin_.Generate(cos, sin);     // cos and sin
+        float yn = yIn*cos - yQn*sin;
+        
+        //-----------------------------------------------
+        myDac_.Write(yn);               // Write to DAC  
+    }
+}