Example Code for Arduino-Multiple Targets Detection

Hardware Preparation

• DFRduino UNO R3 (or similar) x 1
• 24GHz Microwave Radar Sensor x1
• Connectors

Software Preparation

• Arduino IDE

Wiring Diagram

As the diagram shows, the pin 1 to 6 are placed from top to bottom. Pin 1 to UNO 5V, P2 to GND, pin 4 and 5 to UNO digital pin 4 and 5, Pin 6 to UNO GND.

Sample Code

* **************************************************** 
* @brief 24GHz Microwave Radar Sensor

 * @copyright	[DFRobot](https://www.dfrobot.com), 2016
 * @copyright	GNU Lesser General Public License

* @author [Xiaoyu]([email protected])
* @version  V1.0
* @date  2019-03-11
  
* GNU Lesser General Public License.
* All above must be included in any redistribution
* ****************************************************/
#include <SoftwareSerial.h>
char col;// For storing data read from serial port
unsigned char buffer_RTT[134] = {};
int YCTa = 0, YCTb = 0,YCT1 = 0,checka,checkb,Tarnum=1,TargetY1 = 0;
double Tar1a,Tar1b,Distance,Distance1,Distance2,Distance3;
SoftwareSerial mySerial(4,5); 
void setup() {
        mySerial.begin(57600);     
        Serial.begin(115200);
}

void loop() { 
        // Send data only when received data
        if (mySerial.read() == 0xff) 
        {
                // Read the incoming byte
           for (int j = 0; j < 134; j++)
           {
                col = mySerial.read();
                buffer_RTT[j] = (char)col;
                delay(2);        
           }
                mySerial.flush();
                if(buffer_RTT[1]==0xff){
                if(buffer_RTT[2]==0xff){
                  YCTa = buffer_RTT[3];      
                  YCTb = buffer_RTT[4];
                  YCT1 = (YCTa << 8) + YCTb;               
                }
                }//Read obstacle distance of the maximum reflection intensity.
               for(int i=6;i<134;i++){
                if(buffer_RTT[i]==buffer_RTT[i-1]){
                  if(buffer_RTT[i-1]>buffer_RTT[i-2]){
                  Tar1a = i-6;
                  checka= buffer_RTT[i-1];  
                  } //Check the increase of the peak
                }
                if(buffer_RTT[i]<buffer_RTT[i-1])
                {
                  if(buffer_RTT[i-1]==buffer_RTT[i-2])
                  {
                    checkb= buffer_RTT[i-1];//Check the decrease of the peak
                    if(checka==checkb&&checkb>=10)
                    {
                    Tar1b = i-6;
                    Tar1b=Tar1b-Tar1a;
                    Tar1b=Tar1b/2;
                    Tar1a=Tar1a+Tar1b;
                    Distance=Tar1a*0.126;
                    Distance=Distance*100;//Calculate distance
                    Serial.print("Distance");
                    Serial.print(Tarnum);
                    Serial.print(":");
                    Serial.println(Distance);//Output the distance of other obstacles, can read other 3 obstacles at most.
                    Serial.print("D: ");
                    Serial.println(YCT1);//Output the obstacle distance of the maximum reflection intensity.
                    if(Tarnum==1){
                      Distance1=Distance; 
                    }
                    if(Tarnum==2){
                      Distance2=Distance;                   
                    }
                    if(Tarnum==3){
                      Distance3=Distance; 
                    }                                     
                      Tarnum++; 
                    }
                  }
                }
              }           
            Tarnum=1;
       }
  } 

Result

Output Result: output about 5 distance values at most.