diff --git a/Core/Src/yunhorn_sts_presence_rss.c b/Core/Src/yunhorn_sts_presence_rss.c
index bb81cc3..9287bea 100644
--- a/Core/Src/yunhorn_sts_presence_rss.c
+++ b/Core/Src/yunhorn_sts_presence_rss.c
@@ -128,6 +128,7 @@ volatile float sts_presence_rss_distance, sts_presence_rss_score;
 volatile STS_OO_RSS_SensorTuneDataTypeDef sts_presence_rss_config;
 //static void update_configuration(acc_detector_presence_configuration_t presence_configuration);
 static void print_result(acc_detector_presence_result_t result);
+void STS_Yunhorn_DistanceStandardDeviation(void);
 volatile uint8_t motion_detected_count=0;
 volatile uint8_t motion_in_hs_zone[12][10]={0};	//0.4*12=4.8meter high, past 10 measures
 volatile uint8_t detected_hs_zone=0;;
@@ -148,6 +149,7 @@ volatile uint16_t sts_fall_rising_pattern_factor1=0, sts_fall_rising_pattern_fac
 volatile uint16_t sts_roc_acc_standard_variance=0;
 extern volatile uint8_t sts_presence_fall_detection;
 static uint8_t sts_rss_init_ok=0;
+volatile uint8_t sts_presence_singularity=1;
 extern uint8_t sts_lamp_bar_color;
 /* USER CODE END Includes */
 
@@ -665,7 +667,7 @@ int sts_presence_rss_fall_rise_detection(void)
 					//print_result(result);
 					if (result.presence_detected)
 					{
-						print_result(result);
+						//print_result(result);
 						average_result++;
 						average_distance += result.presence_distance;
 						average_score += result.presence_score;
@@ -806,9 +808,12 @@ int sts_presence_rss_fall_rise_detection(void)
 
 	average_distance = (float)(1000.0f*average_distance)/(float)average_result;		// in meters
 	average_score = (float)(1000.0f*average_score)/(float)average_result;
-	APP_LOG(TS_OFF, VLEVEL_M, "\r\nAverage Distance: %d (mm) Score: %d \r\n",(int)average_distance, (int)average_score);
+
 	sts_presence_rss_distance = average_distance;
 	sts_presence_rss_score = average_score;
+
+	STS_Yunhorn_DistanceStandardDeviation();
+	APP_LOG(TS_OFF, VLEVEL_H, "\r\nAverage Distance: %d (mm) Score: %d  Singularity: %d \r\n",(int)average_distance, (int)average_score, sts_presence_singularity);
 	// uint8_t pre_sts_rss_result = (average_result > (DEFAULT_UPDATE_RATE_PRESENCE/5))? 1: 0;
 	// sts_rss_result=STS_RSS_Filter(pre_sts_rss_result);
 
@@ -820,19 +825,27 @@ int sts_presence_rss_fall_rise_detection(void)
 	// sts_rss_result = (average_result > 0)? 1: 0;
 
 	uint8_t pre_sts_rss_result=0;
-	if (sts_work_mode == STS_UNI_MODE) {
-		pre_sts_rss_result = (average_result > 0)? 1: 0;
-	} else {
-		pre_sts_rss_result = (average_result > 0)? 1: 0;
-	}
-	//Write_RingBuff(pre_sts_rss_result);
-	//STS_RSS_Filter_ring();
-	STS_RSS_Filter(pre_sts_rss_result);
+
+		if (sts_work_mode == STS_UNI_MODE) {
+			pre_sts_rss_result = (average_result > 0)? 1: 0;
+		} else {
+
+			pre_sts_rss_result = ((average_result > 0)&&(sts_presence_singularity ==0))? 1: 0;
+
+		}
+
+		//Write_RingBuff(pre_sts_rss_result);
+		//STS_RSS_Filter_ring();
+		STS_RSS_Filter(pre_sts_rss_result);
+
+	//else {
+//		sts_rss_result = 0;
+//	}
 
 	// APP_LOG(TS_OFF, VLEVEL_M, "\r\nMotionCount=%4d  Overall Motion=%d \r\n", (int)motion_count, (int)sts_rss_result);
 	//APP_LOG(TS_OFF, VLEVEL_M, "\r\nAverage Result=%d Distance=%d, Score=%d MotionCount=%d ---Overall Result=%d \r\n",
 		//	(int)average_result, (int)average_distance, (int)average_score, (int)motion_count, (int)sts_rss_result);
-	APP_LOG(TS_OFF, VLEVEL_M, "\r\nMotion Status: %d %d (mm) %d Rated-> %d \r\n",(int)average_result, (int)average_distance, (int)average_score, (int)sts_rss_result);
+	APP_LOG(TS_OFF, VLEVEL_M, "\r\nMotion Status: %d %d (mm) %d singularity: %d Rated-> %d \r\n",(int)average_result, (int)average_distance, (int)average_score, (int)sts_presence_singularity, (int)sts_rss_result);
 #if 0
 	if (sts_rss_result)		//if (average_score !=0) //if (sts_rss_result)
 	{
@@ -913,7 +926,36 @@ int sts_presence_rss_fall_rise_detection(void)
 	return EXIT_FAILURE;
 
 }
+void STS_Yunhorn_DistanceStandardDeviation(void)
+{
+	uint16_t i,j;
+	uint32_t sum_presence_distance = 0;
+	uint32_t average_presence_distance = 0;
 
+	uint8_t SAMPLE_DATASET_NUM = MIN(motion_count,DEFAULT_UPDATE_RATE_PRESENCE );
+
+	for(i= 0; i< SAMPLE_DATASET_NUM; i++)
+	{
+		sum_presence_distance 	+= (uint32_t)sts_motion_dataset[i].presence_distance;
+	}
+
+	average_presence_distance = ((uint32_t)sum_presence_distance/(uint32_t)(SAMPLE_DATASET_NUM));
+
+	sum_presence_distance = 0;
+	for (j = 0; j < SAMPLE_DATASET_NUM; j++)
+	{
+		sum_presence_distance 	+= (uint32_t)(sts_motion_dataset[j].presence_distance - average_presence_distance);
+	}
+
+	if (sum_presence_distance > 0)
+		{
+			sts_presence_singularity	= 0;
+		} else {
+			sts_presence_singularity 	= 1;
+		}
+
+	// APP_LOG(TS_OFF, VLEVEL_M, "\r\n*** STS_Singularity=%u ***\r\n", sts_presence_singularity);
+}
 void STS_YunhornCheckStandardDeviation(void)
 {
 	uint16_t i,j;			//  sts_sensor_install_height  <--- average_presence_distance should be approaching this distance - 50cm
diff --git a/Core/Src/yunhorn_sts_process.c b/Core/Src/yunhorn_sts_process.c
index 2c2da4b..c57cf3b 100644
--- a/Core/Src/yunhorn_sts_process.c
+++ b/Core/Src/yunhorn_sts_process.c
@@ -118,7 +118,7 @@ volatile uint8_t sts_rss_2nd_result = STS_RESULT_NO_MOTION;		//2nd RSS sensor st
 volatile uint8_t sts_tof_result = STS_RESULT_NO_MOTION;
 volatile uint8_t last_sts_rss_result=STS_RESULT_NO_MOTION;
 _Bool Motion_Flag = 0;
-
+extern volatile uint8_t sts_presence_singularity;
 volatile uint8_t sts_rss_cfg_slid_win_threshold=8;
 volatile uint8_t sts_rss_cfg_slid_win_size=12;
 
@@ -1551,6 +1551,7 @@ void Radar_Filtering_clutter(volatile uint8_t *color)
 //
 static uint8_t motion_read[FILTER_LEN]={0};
 static uint8_t idx_filter=0;
+static uint8_t sts_cnt_singularity=0;
 
 void STS_RSS_Filter(uint8_t pre_sts_rss_result)
 {
@@ -1582,11 +1583,21 @@ void STS_RSS_Filter(uint8_t pre_sts_rss_result)
 			//sts_rss_result= ((sum_filter >= SLIDING_THRESHOLD))? 1:0;
 			// sts_rss_result= ((sum_filter > (SLIDING_WIN_LEN - SLIDING_THRESHOLD)))? 1:0;
 			sts_rss_result= ((sum_filter > (sts_rss_cfg_slid_win_size - sts_rss_cfg_slid_win_threshold)))? 1:0;
+
+
 		} else {
 
 			sts_rss_result= ((sum_filter > sts_rss_cfg_slid_win_threshold))? 1:0;
 		}
 
+#if 0
+		if ((sts_presence_singularity == 1 )&& (sts_cnt_singularity ++ > sts_rss_cfg_slid_win_threshold))
+		{
+			sts_rss_result = 0;
+			sts_cnt_singularity =0;
+		}
+#endif
+
 }
 #endif
 
diff --git a/STM32CubeIDE/Release/STS_O2O6O7_pixel_debug_20250421_GOOD.bin b/STM32CubeIDE/Release/STS_O2O6O7_pixel_debug_20250421_GOOD.bin
new file mode 100644
index 0000000..e206585
Binary files /dev/null and b/STM32CubeIDE/Release/STS_O2O6O7_pixel_debug_20250421_GOOD.bin differ
diff --git a/STM32CubeIDE/Release/STS_O7.bin b/STM32CubeIDE/Release/STS_O7.bin
index 0f1e3ae..e206585 100644
Binary files a/STM32CubeIDE/Release/STS_O7.bin and b/STM32CubeIDE/Release/STS_O7.bin differ