added fft threshold into BGT_RADAR_CONFIG_t

Author: Sun Yuxi (IFAG DES SDF FW)

arm/libraries/Radar/README.md

@@ -8,7 +8,7 @@ This library offers support for Infineon's [24GHz Radar Series](https://www.infi
 - [ ] Position2Go
 
 ## Interfaces
-- [x] RadarDataProcessor
+- [x] RadarDataProcessor<br/>
   Several algorithms are implemented to process raw data from the radar. The following functions can be called to enable/disable these algorithms:
   ```
   void enableSimpleMotionDetection();
@@ -17,11 +17,11 @@ This library offers support for Infineon's [24GHz Radar Series](https://www.infi
   void enableFft();
   void disableFft();
   ```
-  - [x] motion detection
+  - [x] motion detection<br/>
     Motion detection (approaching & departing) is implemented based on the phase shift. `enableSimpleMotionDetection` runs the algorithm based on comparing wav shapes of I and Q data, whereas `enableFftMotionDetection` is based on the phase difference of the FFT peaks of I and Q data.
-  - [x] speed detection
+  - [x] speed detection<br/>
     FFT peak frequency is proportional to the doppler speed.
-- [x] BGTRadar
+- [x] BGTRadar<br/>
   Defines radar configurations and parameters for algorithms (different radars might have different data formats)
   - [x] BGT24LTR11 (Sense2GoL)
 - [ ] Communication Library

arm/libraries/Radar/examples/configure_radar/configure_radar.ino

@@ -9,12 +9,15 @@
 int16_t magnitudes[SPECTRUM_SIZE];
 bool available = false;
 
-BGT_RADAR_CONFIG_t user_config = {fft_size : 128,
-                                  cycle_time : 100,
-                                  sampling_rate : 3000};
+BGT_RADAR_CONFIG_t user_config = {
+  fft_size : 128,
+  fft_threshold : DETECTING_MAG_THRESH,
+  cycle_time : 100,
+  sampling_rate : 3000
+};
 
 // this routine shouldn't take too long
-void callback(RESULT_t * result)
+void callback(RESULT_t *result)
 {
   for (int i = 0; i < SPECTRUM_SIZE; i++)
   {

arm/libraries/Radar/src/RadarDataProcessor.cpp

@@ -160,7 +160,7 @@ void RadarDataProcessorClass::computeFft()
 
     //the first half of real fft values replaced by power spectrum
     _maxMagFreq = _fft.compute_magnitude(_result.realI, _result.imagI, _result.magnitudes, _radarFftSize / 2);
-    bool detected = _maxMagFreq.mag > (_radar->_algoParams).magnitude_thresh;
+    bool detected = _maxMagFreq.mag > (_radar->_config).fft_threshold;
     if (_algo.detectMotionFft)
     {
         float maxImagI = (float) _result.imagI[_maxMagFreq.freq];
@@ -172,7 +172,7 @@ void RadarDataProcessorClass::computeFft()
             _result.imagQ[i] = 0;
         }
 
-        // TODO: only one-point fft needed
+        // TODO: only one-point fft needed for the Q data
         _fft.fix_fft(_result.realQ, _result.imagQ, _fftOrder, 0);
 
         float maxImagQ = (float) _result.imagQ[_maxMagFreq.freq];

arm/libraries/Radar/src/radars/BGT24LTR11.cpp

@@ -2,12 +2,11 @@
 #include "BGT24LTR11.h"
 
 BGT_RADAR_CONFIG_t BGT24LTR11::default_config = {fft_size : SENSE2GO_BUFFER_SIZE,
+												 fft_threshold : SENSE2GO_MAG_THRESH,
 												 cycle_time : SENSE2GO_CYCLE_TIME,
 												 sampling_rate : SENSE2GO_SAMPLING_RATE,
 												 settle_time : SENSE2GO_SETTLE_TIME};
 
-BGT_ALGO_PARAMS_t BGT24LTR11::default_params = {magnitude_thresh : SENSE2GO_MAG_THRESH};
-
 BGT24LTR11::BGT24LTR11(BGT_RADAR_CONFIG_t radarConfig)
 {
 	_config = radarConfig;

arm/libraries/Radar/src/radars/BGT24LTR11.h

@@ -32,7 +32,6 @@
 class BGT24LTR11 : public BGTRadar
 {
 	static BGT_RADAR_CONFIG_t default_config;
-	static BGT_ALGO_PARAMS_t default_params;
 
   public:
 	BGT24LTR11(BGT_RADAR_CONFIG_t radarConfig = default_config);

arm/libraries/Radar/src/radars/BGTRadar.h

@@ -7,6 +7,8 @@
 typedef struct
 {
 	int fft_size;
+	/** threshold of the FFT spectrum for motion detection */
+	int fft_threshold;
 	/** one cycle includes ADC sampling, running algorithms, user code, and some idle time*/
 	int cycle_time;
 	/** Rate of ADC sampling*/
@@ -15,12 +17,6 @@ typedef struct
 	int settle_time;
 } BGT_RADAR_CONFIG_t;
 
-typedef struct
-{
-	int magnitude_thresh;
-} BGT_ALGO_PARAMS_t;
-
-
 class RadarDataProcessorClass;
 
 /** @class BGTRadar Base class for different types of radars  */
@@ -45,11 +41,6 @@ class BGTRadar
 
 	BGT_RADAR_CONFIG_t _config{};
 
-	/**
-	 * @brief Parameters for data processing algorithms. Defined here (not in RadarDataProcessor) since these may vary from radar to radar.
-	 */
-	BGT_ALGO_PARAMS_t _algoParams{};
-	
 	int _samplingTime;
 };